^2.'^- Hcc-m ETH/88/013 Field Doc. 18 Government of Ethiopia Water Resources Development Authority BALE GADULA IRRIGATION PROJECT Annex C: Soil Suitability and Land Evaluation Report Consultant V J ,.v, United Nations Development and Agriculture Organization of Addis Ababa June 1992 Programme the United nationsAAA» f »< t •v ;« • ■ '•AS •X ’ A > ;:\The. designations employed ? %iftith !s'*/'publlcation do- not and the presentation of material in 1 imply the expression of any opinion . whatsoever ' on the part ofthe Food and Agriculture Organization ro ^oAitheiiUnited’:Nations concerning the legal status of any country, '•x^territory$ city or area or of its authorities, or concerning the delimitation of it6 frontiers or boundaries, .t (, • • / 'i ; Jk J t* < S* ■ ■*’ ■* ,'v-M • ' • *•<? ~T ; i* *• ’ ' • ■, 11Il 7 i• f T, TABLE OF CONTENTS SUMMARY AND RECOMMENDATIONS 1 INTRODUCTION THE ENVIRONMENT 2.1 Location , a. Location » b. c. Access . . Extent.. ■ • » 2.2 Climate a. General Characteristics b. c. Soil Moisture Regime... Soil Temperature Regime * I 3 - Natural Vegetation and Present Land Use 2.4 - Physiography, Geology and Drainage SQIfc SURVEY METHODS 3.1 - Pre-survey activities.... 3.2 - 3.3 - V.Mw- Field Operations Post-Fieldwork Activitier "SOILS AND-DESCRIPTION OF SOIL LAPPING UNITS. . . . i 4 ..I - The Soils and their Taxonomic Classification 4.2 - Detailed Soil Map Legend 4\3 - Description of Soil Mapping Units IRRIGATION WATER QUALITY »<• LAND SUITABILITY FOR IRRIGATED AND RAINFED AGRICULTURE. lt^vLand Development Requirements and Limitations for surface Irrigation a ? Vegetation clearance i b. Removal of Surface Stones »; c .• Land Levelling Land Development Classesfl I I, r'• -T : TABLE OF CONTENTS Page 6.2 - Evaluation of the Soils (Soil Fertility) 6.3 - Crop Requirements and Crop Suitability of the Soils and the soil and the soil mapping unit mapping unit 6.3.1 General description of suitability classes and subclasses 34 37 37 i 6.3.2 Major requirements of the crops shown in the crop suitability table 6.3.3 Major differences in land evaluation for irrigated and rainfed agriculture REFERENCES APPENDICES: Detailed Soil Profile Descriptions and Analytical Data Hydraulic Conductivity and infiltration Rate laboratory procedures LIST QF FIGURES Irrigated Crop Suitability Map of the Bale Gadulla Site Location Map Mean monthly rainfall, Goro Mean monthly air temperature, Goro Areal photo-interpretation map of the Bale-Gadulla (phase I) area. 39 45 47 49 49 69 74 iii Figure 1- . 2 - 4 Approx scale 1:50,000 Schematic Cross-Section of the Bale-Gadulla (phase I) area Soil Map of Bale Gadulla feasibility Study area Optimum Altitudes for Major Crops in Ethiopia.........•••••■ 4 7 7 9 10 19 334 I ■ ■ LIST OF TAE’.ES TABLE 1 - Rainfall, Goro 2 - Air temperature, Goro 3 - Hectarages (and % of total area) of all mapping units TABLE 4 - Chemical Analysis of the W-ib river irrigation water 5 - Preliminary land levelling classes and related mapping units and their extent 6 - Land development limitations, requirements and classes of all soil mapping units Irrigated crop suitability of the Bale Gadulla (phase soil mapping units Rainfed crop suitability of the Bale-Gadulla General land rainfed crop (phase I) soil mapping units Lage 6 6 28a 29 33 35 43 44 evaluation for irrigated and cultivation of the Bale-Gadulla (phase I) soil mapping units 46Summary and Becow . - The area surveyed for the Bale Gadulln, phase I feasibility study, covers about 968 hectare. Of this approximately 4 6 ha (or covered by Kubsa village. of the total area) is In total about 583 ha (of 60 of the total area) is moderately well suited for irrigated crop cultivation. It consists of nearly level togently sloping (li/>-3% slopes), very deep (3-8m depth upto the bedrock), somewhat imperfectly drained, slowly permeable, black cracking?clay (or silty clay) soils. These lands have been somewhat downgraded because of difficult work ability for seedbed preparation and problems related to restricted subsoil drainage (suitability subclass s.d,) Approximately 218 m ha (or 2 2 downgraded as only marginally suitable of the total area) has been for cultivation. It consists mainly o£ the same brownish black) cracking clay soils, underlying bedrock and/or very sodic but either or with 3 irrigated crop black (sometimes < 3m deep to the •./a-4% slopes and thus more subjected to erosion hazard (see suitability subclasses: S.d a ■> S.ad, 1 S.d" 3 and S.d’w) ■’•’ -- .'Vfl - :• •< .. ^’^They.remaining 120 (approximately) or 12 ixa of the total area, /consists of steep rocky hills, ' >y^(-s lopes? > 4%) and is -A* Z* ' ‘ J ’ ■*--- , footslopes and steep sideslopes • ■ p” ^development (suitability therefore not suited for irrigation subclasses: N.sr. N.se) t. 1 •pit may further be noted •pit may further be noted that, although a very large part of the project/area (about 4 Olizi ha, or 4 1". of the total) is covered by common to many surface stones (of vesicular basalt), their removal ;(by.-hand-picking) would only take (or cost) about 13 mandavs per hectare or 40 Birr per ha) and this will amount to a stone heap /pf^Sibp.utpil 12m stones per ha, which may be used for other purposes, jisuch "as the^construction of roads or walls. yro^enabLeJ.the construction of the irrigation scheme, only the river ^terrapeS^C.T-mapping units), covering about 393 ha (or 41% of the * '.•xtotall^area )£ are in ; need of some ^requirements, while all the other already'-'"cultivated (rainfed) . low vegetation clearance suitable mapping units are W ■ • ", .ff' I.' ,Moreover/ about 132 ha (or I3iz>% oi suitable’■'lands are in need of medium 2i/j-3%l'slopes) and about 112>/« ha (or levelling/grading operations. total area) of more or less levelling/grading (with lliz»% of total area) of high r .v. •j •< i ■J VJ !■ mJ IB la a a a a a a a a i aIt should•finally be noted that, due to the low annual rainfall, about<583 ha (or 60>/>% of the survey area) will be upgraded from only marginally suited under the present rainfed conditions (class S3)to;moderably well suited (class S,) under irrigated conditions. This may-roughly indicate an expected productivity increase from belowx'40% to about 60% of that achieved from ideally suitable land under the same level of inputs. i I 1 I □Ci:.r • y i I fix ■ t Xi# A-sfe - » ii3 ■ d i ■ H It d d t dRepresentative profile: BAGO01 These soils general ly occu r on the undulating or convex upper part of the Older Va lley Bottom in association with the Weyib soil series havi ng a deeper calcic Horizon (=below 115cm depth or more). According to the revised (1988) legend and the (June 1991) annex 1 of the FAO/UNESCQ/ISRIC soil Map of the World, these soils with fine, cracking clays and intersecting slickensides within 100cm of the surface, have been classified in the soil group of Vertisols and in the soil unit calcic vertisols (VRK), (=liaving a calcic horizon within 125cm of the surface) and soil subunits Hypo-Calcic Vertisols (= >the calcic horizon consists of concentration, of soft powdery lime). And because they have chromas, moist of 1.5 or more, they may receive the prefix chromi, thus Chromo- Hvpo-Calcic Vertisols. Similarly to the above, those soils have been classified in the order of Vertisols in the U.S.S.Q11 Taxonomy System (Key, 1988), and suborder Usterts (==ustic soil moisture regime) and great group Chromus1 erts (= having chromas moist, of 1.5 or more) and subgroup Udic Chromusterts (=having cracks that remain open from 90 to 150 cumulative days in most years). 2- Wevib soil series: They a. e the dominant soils of the phase I project area, covering the gently undulating lower .■part with many surface stones) and/nearly level to gently z'^'cpncave depressions and drainage ways (with few surface '•/■‘ ABtones) of the predominantly cultivated older Valley Bottom, •$; ■ as the Upper and Lower River Terraces without (or few) V < surface stones. They are also very deep (mostly 3-8i/am deep to bedrock), somewhat imperfectly drained, very slowly permeable, slightly ■to moderately calcareous (8-15%Ca Co ), with no calcic a horizon within 125cm of the surface, strongly alkaline (PH (H 0) 8.2 - 8.6), only occasionally sodic (ESP of 36-39% a . . /. ‘ % below 40cm depth), black, cracking clays (60-90% clay in the fine earth fraction). ^Representative Profiles: bago04, bagoos, bagoo6, bagoo7. the Kubsa soil series, these soils have been *•' 'Classif ied/ in the subgroup of Vertisols, according to the . EAOZUNESCQ/ ISRIC(1988) revised legend and in the soil unit EUtriC ^VertlSQlS (=not having a gypic or calcic horizon within* 125 cm of the surface but with a base saturation of jmore^/than 50% throughout the profile). Because of their ^chromas moist of 1, they have given the prefix Pelli. Thus -Pelli-Eutric Vertisols. 140 0 0 0 0 ■ 0 0 0 0In the US s_oi.l_ Taxonomy Svs t*. in (Key, 1988) they are also Vertisols (=order) and Usterts (suborder) because of ustic soil moisture regime and great group £^lus_teiLt£ (because of chromas 1), and subgroup Udic Pellusterts (=having cracks that remain open from 90 to 150 cumulative days in most years. 3- Asendabo soil series: They are the dominant soils of the non cultivated Middle River Terrace, predominantly with no (or few) surface stones and medium dense Acacia shrub land. They are similar in all aspects to the Kubsa soil series, but always black in colour and with a higher percentage of silt (31-53% silt in the fine earth fraction) and thus £_ll_Ly clavs. They have a calcic horizon usually between 63-117cm of the surface and they are moderately alkaline. Representative profiles : BAGO 07* and BAGO0 3 Similarly to the Kubsa soil sei ies they have been classified in the soil subunit of Hvpo-Calcic Vertisols (FAO/UNESCO/ISRIC legend, 1988/>1), but with a prefix Pelli, because of their chromas, moist of 1, thus Pelli-Hvpo- Calcic Vertisols. Likewise, in the US Soil Taxonc iv System (key 1988) they are classified in the subgroup of V llc_JReJLLusJl.ejLts. 4.2 Detailed Physiographic soi ^laap legend On the basis of physiographic landform, slopes, surface stoniness and land use and vegetation cover types and soil taxonomic characteristics, the following physiographic soil mapping units were delineated within the phase I Bale- Gadulla project site. 15■ UFhysiographlc Soli Map Legend of the Bale-Gadulla Area Mapping Physiographic Description, unit including vegetation cover Syibols type, slope disses and depth to bedrock soil series naie (Soil Tixonoiy, FAO 1983 variants, phases) and najor soil profile characteristics Irrigation Suitability subclasses ? • Plateau, outside project area not surveyed not relevant H ‘ Steep Bills and footdopes; pred. under grassland and liny surface stones Hl Very Steep and locky Sunits lockland (vriculnr basalt) B2sr and upper slopes H2 > Steep footslopes (8-31 slopes: Hot med (Kolllc Fluvisols, M2S < l]i deep to bedrock ■S- rudic phases). Moderately d-ep, well X drained, brownish black. silty loan over gravels Pred. cultivated, Undulating Older Valley Betton Ondulating or Convex Upper Part: pred: 3-h deep '.c bedrock: Ccnacn to nany surface stones (vesicular basalt) 711 Strongly sloping ;I-H) slopes' upper slopes; lore dissected ■*.» * f' Gently Convex Lower Slopes (lj-31 slopes; / •* ' • •.i Xubsa soil series calcic Vertisols; rudic phases see Kubsa soil $ ties Hypo Click Vertisols, rudic phase}. Very de (Cbrcii- odic, Nied ska senewbat isperfeotly drained, brownish black, craokic; clays with a calci: horkot within !2‘ca depth (Bepr. profile B-'.) Gently Undulating Lower Part; pred. 5-S|i. deep l: bedrock; Concn to nany surface stones (vesicular basalt; to very gently ’sunnits il{-2t slopes convex (2J-U slopes) slopes Deep |f-H) Sideslopes to Weyib Weyib soil series {Pelh-inlrk Vertisols, ludtc phase). Very deep, mewhe: iiperfectly drained, black, craokk; clays tkepr. profile: B-5) Weyib soil series: rudic phase as above Veyib soil series: kudu phase as above Weyib soil series . Bodie Phase Side S'.dw Sled Nied• ■■r • / •. Physiographic Soil Map Legend of the Bale-Gadulla Area Mapping Physiographic Description, Unit including vegetation cover Syibols type, slope classes and depth to bedrock River valley. Soil senes naie (Soil irrigation Taxonoiy, FAO I90fi Suitability variants, phases) and subclasses lajor soil profile characteristics as above VI Nearly Level to Gentle Concave Drainage Ways and Depressions; Pred. 3-5i. deep to bedrock; aostly none or few surface stones V31 Narrow, Concave drainage ways: Weyib soil series: as above, Sled (3)-4% slopes) but non rudic V32 Broad depression without surface Veyib soil series, non rudic S2dw stones V33 Broad depression with iany Veyib soil series (Pelli-lutric Slid surface stones. Vertisols, sodic, rudic phase) Very deep, soiewnat iiperfectly drained, sodic cracking clays (Repr. profile: B-6) i T 11 Til dearly level River Terraces with Scattered Bu6h Vegetation Upper lenace •r Slightly convex Suants: upto 2|t slopes; few rock outcrops, pred, <3i deep to bedrock Nearly level suiaits; l-l|l Slopes; pred. 3-4i. deep to bedrock Veyib soil series i?elli-Jut: Vertisols} (See T12 unit) Veyib soil series [Pelli-lutric Vertisols, ncn-rudic phase) (Repr. profile- 3-7) Sld’v S2dw Transitional footslopes.belcw H: f-7 is lopes; iaay 6'jrface stones: pred>-2i, deep to bedrock Kid ■» ■ « TU^Very 9t“th sloping |2t slopes,: . .fy^CCHcn tc nany surface stones: pred iOSfdiV deep to bedrock Nearly level suinits: 1-11% Slopes pred. >5i. Deep to bedrock Asendabc sell series I’elli- Hypo-Ca’.cic Vertisols, rudic phase) . Ver • deep, soievhat iiperfectly drained, black tc orewnish black cracking, silty clays, with a calcic hcritca within Keen depth (Repr. profile: =-l Asendabo soil series |?elli-H7FO Calcic Vertisols, rudic phase); Asendabo soil series (Felli-Hypo Calcic Vertisols, ncn-rudic but sodic phase) Very deep, sciewhat iiperfectly 17Physiographic Soil Map Legend of toe Bale-Gadulla Area Napping Unit Syabols yhysiogrspbic Description, Including vegetation cover type, dope classes and depth to bedrock Soil series naae (Soil Taxonoiy, FAC BBS variants, phases) and aajor soil profile characteristics Irrigation Suitability subclasses • drained, biack, cracking, sadi: boriron within 125 depth silty clay--, with a calcic [Repr. prclile: B-3) 124 Sideslopes (3|*H slopes) with Asendabo Soil series as S3d*e few rock outcrops; pred. <3i above: sli-htly rocky phase deep to bedrock T3 Lower Terrace Nearly level [< H slopes'.: pred. Weylb soil series (Pelli-Iutric Vertisols]. Very deep. Eoiewhat iiperfectly S2dw 3-5a deep to bedrock drained, black, cracking clays (Repr. prefile: B-4). A Al A2 Alluvial area valleys, outside project Not surveyed NOt relevart k.sendabc dry valley, with basaltic Keyib valleyGOVERNMENT OF ETHIOPIA WATER RESOURCES DEVELOPMENT AUTHORITY wo^wo.-CTM/’.e/o.s- THtc ' BALE GADULA IRRIGATION SUITABILITY MAP1. INTRODUCTION The report outlines the results of a feasibility soil survey of only a small part (called phase I) of the Bale Gadulla area, which had already been studied in rather detail by a Korean soil survey team together with a national counterpart staff of WRDA, in 1990, at an overall observation density of about 1 per 6 hectare. Afterwards, however, update and improvement of the soil and landform characterizations, the soil mapping accuracy and reporting was felt to be needed. The present study is based primarily on a* detailed aerial photo-interpretation (scale 1:50,000) in combination with about 78 additional field observations and study of the previous soil survey data (abou^ 75 observations) and maps. The new observations observations made at regular transects located more or physiographic mapping units included 71 auger hole intervals of about 200m along less perpendicularly to the •orientation, and including numerous (about 85) soil surface observations as well. Furtheron 7 soil profile nits were dug upto and 4 deep borehole were drilled upto the bedrock, 2m depth All this amounted to an overall hectare• The soil profile sites, described in observation density of about 1 per 4 pits were located on representative detail and sampled for laboratory analysis, i while infiltration and permeability tests were executed ini triplicate near those pits. • * ' - Final •••A- topographic soil boundaries field sheets, were which traced on 1:5,000 were later reduced scale to 1:10,000 scale final maps. j The complete soil survey and described in chapter 3. mapping methodology is The study was conducted in Mekuria ------- :Tafesse, General - ------- Manager WRDA and National Project ^Coordinator ETH/88/013, Mr. S.Thirugnanasambanthar, FAO team ** / ’ f-T' <leader-,?<and the member mar s of the steering Committee for the v vaiw w w C X, X A 4 Ullll X L V c c UNDP/.assisted projects in the irrigation subsector. consultation with Ato ■ '• ■.?A^?The. work was executed in the field with the assistance of^WRDA^ technical staff, including including Ato Girum Ato Girum Asfaw > (the national , soil survey counterpart)I and Ato Melesse and Ato Melesse Kumsa (national soil survey assistant) and Ato Mesfin Kidane and assistant) and Ato Mesfin AtO£'>Birhane Gashu (topographic (topographic surveyors). The deep bor.eholes -- ----and ----their descriptions were descriptions were made i by Ato Teodros G/Egziabher (geologist) and Ato Bulcha Nigatu 1 (driller). » t .• ••r i Si yI II to to to to I I 51 I g I II I 1 The terminology used for soil description, taxonomic soil classification and irrigability evaluation in the report is explained in USDA (1951 and 1988) and FAO (1976, 1977, 1979, 1985 and 1988). Of the 4 different soil series identified » in the project area only three have been tentatively named, and described in detail in this report, since the fourth one is very limited in extent and not suited for irrigation,because of steep slope and relative shallowness. The three major soil series are very similar:in most profile characteristics. They are all very deep, somewhat imperfectly drained, black to brownish black, moderately to very strongly alkaline, occasionally sodic, medium to highly calcareous, non-Baline, cracking clays (vertisols). Their names (see below) are derived from the Kubsa ' village located in the phase I area, the Weib and the Asendabo. rivers, respectively. •/, Their differing characteristics and taxonomic classification are: 1. Kubsa soil series (Chromo-Hypo-Calcic Vertisols; FAO, 1988/91) Brownish black clay (with 15-32% silt and 65- 85% clay), and a calcic horizon of soft powdery lime in between 60-110cm of the surface. These soils have both a rudic (^surface sodic (ESP upto 28) phase. stones) - and a Asendabo soil series (Pelli-Hypo-Calcic Vertisols; FAO •1988/91) Black siltv clay (with 30-55% clay) and a calcic___ horizon of soft between 60-120 cm of the surface. silt and 45-65% powdery lime in 3• • z ; Weib,soil series (Pelli-Eutric Vertisols; FAO, 1988/91) - V- <• Bla.sk Glaxfi (with 9-37% silt and 60-90% clay) and a very deep (below 125cm) or no calcic They mostly have a rudic sodic phase.. A.-, Complete description of (= surface horizon. I stones) and rarely these soil j series (and phases).is. given in appendix results^of the soil samples their I, together with the analytical taken and of the infiltration .and permeability tests, Determinations of intake family is given^iri'appendix II. Total depth of the (sub) soils, until the bedrock and brief descriptions is given in appendix III.V I I I I 9 I 2. THE ENVIRONMENT 2.1 Location, access and extent of the ..Pr9~lect area a. Location The project area lies in a valley on the left bank of the Weib river in Gadulla awraja, about 30km from Goro, at an altitude of around 1900m. (see figures 1 and 2). - Its location is roughly in between 07° 06' and 07° 09' Northern Latitudes and 40’ 22' and 40’ 24' Eastern longitudes or according to the Universal Transverse Mercator Grid Designation (Zone 37, clarke 1800 spheroid) inbetween 16,000 and 19,500m North and 652,500 and 657,500, East. The area can be found on 1991 aerial photograph no 0034, run B2 (contract ET 1:10, scale l;50:000). and on 250,000 scale toposheet. b. A£ge.££ The project area is about 30 km from Goro, and about 80 km from Robe, Between Robe and Goro there is a good all- weather dirt road, From Goro the road deteriorates and for the last 18km it is no more than a track to Kubsa village located in the project area. The area surveyed for the phase I project covers about I I 968 ha, of which about 60i/»% (583 hectare) are moderately suitable for irrigation development. General Characteristics Meteorological data for the project area are not available. Climate“’ r The nearest meteorological station is at Goro; monthly rainfall and temperature data for this station given in Tables 1 and 2 and in Figs, i and 3,. c • * % J • ' i are Rainfall is eratic at Goro. which;;records are available, the l,383?mm and the minimum 351 mm. ^Sb''The mean annual rainfall is In the 11-year period for maximum annual rainfall was about 723.9 mm: about 50% of it is received during Ma . April and May (Belg) and rch, more , ,... ^h- , a n in September and October (Mehr), while the other 7 •months are relatively dry, having only 20% of the total annual rainfall. 3 I TThe survey area has an elevation ranging from 1790 to 1915m. Air temperatures at Goro (which is located at an elevation of about 2,000m.) are very uniform throughout the year. On the basis of the three years of available data, mean monthly temperatures vary between (June) and 19,6°c (January). Mean monthly minima vary between 7.4 c (October) and 11.6’C (January), while maximum vary between 24.4‘C (June) and 28.2'C (February). The mean monthly pan evaporation varies from 128 mm (September) to 180 mm (March) with a mean annual of! 1732 mm. The mean daily wind velocity varies between 1,5 m/sec. to 4.0m/sec. with.the high wind speeds occurring from June till August. b. Soil moisture regime No exact data on soil moisture are available in the Bale-Gadulla area. It has tlr’s to be estimated from the rainfall data. The somewhat imperfectly drained and nearly local to gently undulating upland Vertisols are considered to have an Ustic soil moisture regime, which means a dry upper subsoil format-least 90 days (cumulative) and at least moist in some parts for at least 90 consecutive days. c. Soil Temperature regime - This has also to be estimated from the climatic (air temperature) data. va. The mean annual soil temperature at a depth of 50cm is most .probably higher than 15’C and lower than 22’C, and the difference between mean sumner and mean winter soil temperature is less than 5'C, and thus it is classified as isothermic. 2 • 3 Natural vegetation and present Land use The nearly level terrace landforms (6ee T - Mapping units), along the Asendabo river are not cultivated and covered <by a medium dense bush forest of Acacia and often shorthand tall trees. These areas are presently used for • The more undulating landforms (see V-mapping units) arekalmost entirely cultivated.M I I I I n 9 Table 1. Rainfall, Gone I*’ Kean loathly rainfall |n) based on 11 years' data, 1976-86 'Jan Feb Kir Apr Kay Jun Jul Aug Sep Oct Kov Dec Total U.S 21.2 110.6 136.6 135.3 46.2 12.1 32.0 111.9 77.1 21.3 5.1 'I a J 723.9 I l;V I Table 2. Air teiperature, Gorro Mean loothly air teiperatures Ideg.C) based on 3 yea.s' data, 1982, 1584, 1985 JiD Feb Mar Apr Kay Jua Jul Aug Sep O:t N:7 De: Mean a•*■a• ........ ............ ...... ....... ------ ...... ...... ...... ........ Kin <114. 10.5 10.1 10.2 9.7 10.1 10.0 10.3 9.3 74 104 10.0 1G.0 Mein<.19 4 19.4 184 13.0 17.7 17.3 174 184 17.9 17.1 18.9 18.9 ia.3 MaX>«- 274 28.2 27.2 25.7 284 244 25.2 264 264 26.7 274 274 264 i Ao• f";.- :I I I I 1 .. •> - - ■ Farming practices are traditional ploughing by ox. main rainfed crops are maize, barley, wheat, oats, r . The and different spices. ( mair.e, barley, wheat, oats, sorghum (cumin, fenugreek and coriander). In terms of land area, barley is the most important Barley, Wheat and Oats are all grown in both seasons are .the spices, but maize seems to be usually grown Belg only. 2.4 Physiography, Geology and Drainage As can be seen on the 1:50,000 scale Aerial crop, and so in the Photo- Interpretation map (Fig. 4) and the schematic cross-section four ) (Fig. 5) of the Bale Gadulla (phase I) area three (or four) major landforms have been distinguished. They are: P= The Plateau with undulating summit (P,) above elevation (often with large State Farms) very, escarpments (P2) and steep lower foothills(=H on the soil map). All these units, except H, are located outside the area surveyed. 2300m steep final i V= The undulating Older Valiev Bottom, which is predominantly cultivated and mostly covered by common to many basaltic elevation This surface stones. Within the phase ranges from 1825-1900m. I area, its unit has been subdivided mainly on the basis of slope (degree and form) into: -*A . . ■ * J VI - undulating or convex upper part :V2 - gently undulating lower part V3 - level to gentle concave drainage ways and depress ions • r t . .... T= Nearly level Terraces along ______ the Asendabo river. They are covered by medium dense Acacia bushes and with few or no surface stones. Their elevation ranges from 1785-1840m. Three different Terraces have been distinguished Tl/ ? T, and T, ; (upper-, middle-, and lower terrace respectively). < "'i / _5 :■ I r 1? 's. •• ' :. .t ■ •< , < A= Alluvial _ uvalleys of the Asendabo dr , y river bed (A, ) • 'and the Weib river (partly a deep canyon) plateau and foothills, as well as the valley bottom ' and^terraces'are underlain by vesicular basalts (similar to the^surface stones) of the lower Tertiary (Paleocene Oligocene- Miocene) Trap series (Ashangi group), according to the?. Geological Map of Ethiopia (Scale 1:2 million), compiled y . •• .• . ■ ■■ I byAVrVKazmin (United Nation, 197<!) . ■ •!?> >•. ■<> <<-■ ’ >4^ Both rivers, the Asendabo and area to the Southeast into the ’/abi Weyib, are draining the shebelle river system. « 8 ■ ;<r tj •i r.r...........• IiE T |tlO 82 STOS__________ OOM____________ 7600 Z0-I-I99II I i Schematic cross- section of the Bale - Godulo ( Phase I)area I I x Dense forest Medium dense acacia shrub forer I » Common to many surface stones Knick S | W .I W T 23^2- — 2300- 2200 JV-A < f* ■ '' ,■ T-’ •. 2100^ Asendabo Asendabo and Weylb river Junction •”4>’ 2000- l,;*• J 1900 - 18003. SOIL SURVEY METHODS 3.1 pre-survey activities Maps and reports of the 1990 Korean soil survey were collected and studied as well as the 1991 (scale 1:50,000) aerial photographs, which were interpreted in detail. A preliminary physiographic legend for soil survey purposes was established and on the basis of photo interpretation mapping units, transects for highly intensive soil survey observations and representative sites for soil profile pits and deep borehole drillings (upto the bedrock) were located. All this was then transferred to 1:5,000 scale topo sheets, with lm. contour intervals to be used in the field. 3.2 Field Operations Systematic soil survey work for the of the Bale Gadulla (phase I) area started was completed by the end of February 1992. The soil survey fieldwork involved. Systematic auger hole observations were made along the transects at over a total length of about 14km. holes were made. feasibility study on 23 January and upto 200cm depth intervals of 200m, In total 71 auger •In between these auger hole observations, continuous so-called, (shallow) soj 1surface observations were made with special attention for changes in soil surface colour, stoniness, slope and vegetation cover etc. In total at least of such observations were recorded by a brief code and/or boundary line plotted on the map. : . ■ - ;u- *. Detailed soil profile descriptions were made representative sites, including soil sampling .laboratory analysis. In total 7 soil profile pits made upto 2m. depth. 'Near A of the above mentioned soil profile pits a --■hQrehQlfi was drilled upto the bedrock. on for were deep JJ^hus^in; total 71 + 85 + 7 = 163 new together with the approx ,—- ----------------- —— observations were made. 75 old observations over \an , area of ■ about 968 ha, resulted in an average observation density of 1 par 4ha. •'' ■**a‘*k * B e s1de s XuXlltratiQn-anfl_________ permeability tests were executed in triplicate on ill 7 soil profiles sites. 113.3 Post Fieldwork activities After completion of fieldwork, all data had to be interpreted, including the laboratory results, which were received from WRDA's laboratory on 24 and 26 March 1992. PF values and bulk densities to be determined by the national Soils Laboratory, however, where only received on 17 April 1992, and the calculated results of the infiltration and permeability tests were also handed over by the national counterpart on 17 April 1992. Correction and update of the final (1:10,000 scale) draft soil map and legend, was completed on 10 April 1992, while the final (draft) Irrigability Map was completed on 21 April 1992, after receipt of all the data. The feasibility draft report (including the drawing of schematic cross-sections and graphs and small maps) started in early april and was completed on 4 May 1992, when it was handed over to the project staff of WRDA for final checking, typing and drawing. 12 — ■■I tSOILS AND DESCRIPTION OF SOIL CAPPING UNITS 4 . l The soils and their Taxo:\Qmlc classification Inspite of the 18 physiographic soil mapping units delineated, soils within the phase I project area are very uniform and similar in profile characteristics. Apart from one unnamed soil series occurring on the alluvial-colluvial footslope (lla) below the steep rocky hill (H,)and which is very limited in extent (15i/« Ha only) and not suitable for irrigation development because of steep slopes (8-9%) and not very deep soils (<_ li/im to the bedrock) all other (three) 6oil series differ only from each other in soil colour (very slightly: Pellic or just chromic), depth (or presence)of a calcic horizon (within or below 125 cm of the surface) and soil texture: being either silty clay (with 31^ 53% silt) or clay (with < 32% silt) and slightly in soil reaction (pH) being either strongly to extremely or moderately alkaline. Otherwise these three soil series (collectively covering about 938 ha(or 97% of the project area), are all very deep, somewhat imperfectly drained, black to brownish black, moderately to very strongly alkaline (occasionally sodic), medium to highly calcareous, lion-saline, cracking clays (= Vertisols). .• • Their tentative names (see below) are derived from the /.Kubsa Village located in the phase I area, the Weyib river, /forming the southern boundary of the phase I area and the Asendabo river, forming the north and eastern boundary, respectively. . These three soil series are described in detail under appendix I, together with their laboratory analytical data. Their main characteristics and diagnostic criteria are as follows: 1.7 Kufcsa—SoliSeries: They are the dominant soils of the undulating or '.convex upper part of the Older Valley Bottom (VJ, partly dissected and with 2i/a-7% slopes and ' ; .predominantly cultivated and/or covered by Kubsa 7.. ’-yvi’llage, and with common to many surface stones of •• ^vesicular basalt. ' are very deep (3-4m deep to bedrock), somewhat '^imperfectly drained, very slowly permeable, slightly to .»highly, .calcareous (9-25% Ca Co,) with a calcic horizon within ,Ql2,5£jcm.) depth, moderately alkaline in the topsoil and very ^strongly alkaline below (PH(H,O) 8.0-9.4), sodic below 20cm Adepth'(ESP 9-30% of CEC), brownish black, cracking clays (65- ‘.■84% clay in the fine earth fraction) .Si St S,•M \ \ "'• l \V • P GOVERNMENffok’ ETH|6p!A5.V?'! ' WATER ^RESOURCES jEVELOPM^^AUTBOran r;X 7TV* ^jecr. ?.-' 3\V-£4.3 Description of phvsiographis SQll mapping Units In this section the 18 mapping units shown on the physiographic soil map (scale 1:10,000), are described in more detail and their hectarages (and percentage of total area) are given. Mapping Unit H, : Steep, Rockv Hl Lis 14m ha(l)% Qf total—area 1 This unit is too elevated (above command elevation), too steep and too rocky for any irrigation development. It is covered by grassland and many rock, outcrops and surface stones of vesicular basalt. Irrigation suitability subclass: N.sr. Mapping unit H.: Steep Footslopes: 8-9% slopes:ISA .ha—(Qf total ar^.al- Qf o- Moderately deep, well drained, good permeable, yellowish brown to brownish black, silt loam over gravels. It occurs on the steep alluvial-colluvial footslopes below the steep rocky hills. Brief Profile Description 35cm Brownish black, strongly calcareous, silt loam 35- 7.5cm. Dark yellowish brown, strongly calcareous silt loam I' 75-140cm. 140cm. Dark yellowish brown, strongly calcareous gravelly silt loam. Rock (vesicular basalt). The natural vegetation consists of grassland soil reaction (pH) is strongly alkaline. This unit is too steep for irrigation development. Irrigation suitability subclass: N„ Mapping, unit vTT: Kubsa soil series, strongly (4-7%)sloping. Rudic Phase. Approx. 39$ ha (or 4% of total area) Very deep, somewhat imperfectly drained, very slowly permeable, slightly to highly calcareous, moderate (topsoil) to extremely (subsoil)alkaline. sodic(subsoil). brownish black. cracking clays. It occurs on the moderately dissected, undulating upper part of the older valley bottom. This unit is partly covered by Kubsa village, some grassland and some cultivated lands and all of it has common to many surface stones of vesicular basalt. 20 VBrief Profile Description A, A, Bk 0-20cm. 20-63cm. 63-110cm, Brownish black; well developed, very fine and fine subangular blocky, strongly calcareous, clav. pH8.0 Brownish black; moderately development, medium to coarse, angular blocky including wedgeshaped; strongly calcareous, cracking clay. pH 8.4 (9% exchangeable sodium percentage). Brownish black; m-derately developed, medium to coarse, angular blocky including wedgeshaped; extremely calcareous, with concentrations of soft lime concretions or pseudomycelium; cracking clay. pH 9.4 (27% ESP). B, 110-170*cm Brownis coarse, h black; moderately developed, medium to angular blocky including wedgeshaped; ' ’«.• extremely calcareous, cracking clav. pH 9.2 (29% E.S.P.) This soil is in general only marginally suited to most (climatically adapted) crops. Its suitability is mainly downgraded because of its extreme sodicity in combination with restricted subsoil drainage,and also to some extent because of its difficult workablity for seedbed preparation. This particular mapping unit, however, is considered as not suitable at all, because of its steep slopes (and erosion hazard). Irrigation suitability subclass: Nlse Land development requirements of this unit have been rated as high because of its severe topographic limitations. ■r. Mapping Unit Vv l• 2 • Kutas a——S'-ries. gently (21-3%) sloping. uidic Rudic pl,a_s£. approx. 68 ha (or 7% of total area). Similar to vu above, but only thus less subjected to erosion This unit occurs on the gentle of the upper part < Its suitability foi E the older irrigation gently sloping and hazard. convex lower slopes valley bottom development downgraded because in combination subsoil depth of wi th (3-4m) marginally suitable. restricted subsoil high sodicity and upto the bedrock, A further limitation difficult workability, asas mentioned Irrigation suitability subsubclass: class: S,a .. has been drainage 1imited as only is its above. Land development requirements of of this this unit are because of moderate topographic limitations. medium*10 ■ ■ » '■ M J ■1 ■ >Mapping unit vai: ftevib soil series^—nearlY_level to very qantly A, 0-20cm A. 20-57cm B„ 57-122cm (lizi-2%> slopes, Rudic Phase Approx. 166>/» ha (or 17of total area). Very deep, somewhat imperfectly drained, very slowly permeable, slightly to moderately calcareous, strongly alkaline, felasK, cracking clays. It occurs on the nearly level to very gently undulating summits of the lower part of the older valley bottom. This whole unit is cultiyated and with common to many surface stones (of vesicular basalt). Brief Profile Description Black; well developed, fine and medium, subangular blocky; strongly calcareous siltv clav. PH 8.6. Black; well developed, coarse, angular blocky including wedgeshaped; strongly calcareous, crackinq clav. PH 8.0. Brownish black; well developed, coarse, angular blocky including wedgashaped; strongly calcareous snacking clay■ ph 8. i. *-••• 122-160cm Black with grayish brc-'n concentrations of soft lime concretions; extremely calcareous, cracking clav. PH 8.4 ,'r. . . T r■ r ■ . >. • •»* > • V > f:. :* v J -Jr Mapping Unit This soil is in general moderately well suited to most (climatically adapted) crops. Its suitability is somewhat downgraded because of its difficult workability for seedbed preparation and problems related to restricted subsoil drainage. Irrigation suitability subclass: Sldw Land development requirements are low, except for the possible need to construct a drainage system of about lmeter deep ditches at regular intervals. Depth to bedrock of this unit is about 5 to 8 i meter. i: Weylb sqU .series, >tentlv (21-3^) sloping, Rudic abase Approx. 47 ha (or 4i/*">. of total area). Similar to V21 above, but it occurs on the gentle convex slopes of the lower part of the lower valley bottom and is slighlly more subjected to sheet erosion. Irrigation suitability subclass: Sad, Land development requirements are low because of light topographic limitations only. IMapping Unit V„: Wevib soil series. (3l-4%) sloping, CUdlC Phase Approx. 36Jha (or 3i^ of total area) Similar to Vn (and V„) above, but it occurs on the somewhat steeper convex slopes of the lower part of the older valley bottom, and is thus more subjected to erosion hazard, for which reason it has been down graded as only marginally suitable for irrigation development. Irrigation suitability subclass: S,.a. Land development requirements of this unit are medium due to moderate topographic limitations. Mapping Unit V,«: Wevib soil series, strongly (4-7%) sloping, rudlc phase Approx 44 ha (or 4i% of total area). Similar to V„ (and V„ and V„) above, but occurring on the steep sideslopes of the lower part of the older valley bottom and severely subjected to erosion hazard. This unit is too steep for gravity irrigation development. Irrigation suitability subclass: N,... Land development requirements of their unit would be very high, due to very severe topographic limitations. Mapping. Unit v,.: H£Y,ib .sail series (31-4%) sloping ,4. •' < Approx. 19 ha (or 2% of total area.) Similar to V„, but it occurs on the narrow slightly concave, narrow drainage ways, traversing mainly the upper part of the older valley bottom. Mostly there are only few or no surface stones on this unit. Irrigation suitability subclass : SJtd • kteYib soil series, nearly level (<L%1 slopes. Approx. 57 ha (or 6% of total area). Similar to V , but occurring in the nearly level M broad depression and mostly without (or few) surface stones. ' Irrigation suitability subclass : Sljw 23•» J JMapping Unit V„: Wevib soil series, nearly leveJ^(<l% slopes.) , rudic, sodic Phase Approx. 21 ha (or 2i% of the total area). Similar to V„ above and also occurring in the nearly level, broad depression, but with common to many surface stones and with sodic phase. Briel Profile Description A, 0-15cm Black; well developed, very fine, subangular blocky; strongly calcareous, clay PH 8.2 A. 15-40cm Black; moderately developed, coarse, angular blocky including wedgeshaped; stronalv calcareous , cracking clav■ PH 8.0. (9% exchangeable sodium percentage, ESP) . B. 40-115cm Black; strongly developed, coarse, angular blocky includina wedgeshaped: ^tronqlv calcareous . cracking clav. PH 8.6 (36%ESP). Bk 115-160cm Black, with grayish brown concentrations of soft lime concretions, extremely calcareous, cracking clay. PH 8.4 (39% ESP). » * i? ■ .A: This unit is marginally suited to most (climatically adapted) crops. Its suitability is mainly downgraded because o£ its extreme sodicity in combination with restricted subsoil drainage, and also to some extent because of its difficult workability for seedbed preparation. Irrigation suitatility subclass : S,., <- /■ 1 . ■*’ • ?’. Mapping Unit T: i: H-EVibS.Qllseries . slightly convex (upto ■f I•. f e slopes 1_with few rock outcrops. Approx. 17 ha(or 1j/«% of total area) f Similar to V , ai etc, but it occurs on the slightly Str convex part, with few rock outcrops, of t he upper f ■; . ... river terrace. This unit is uncultiva ted and » covered by medium dense Aca cia shrubland and with few or no surface stones. Subsoil depth to the t• j■ '■» •Si’ • 7 bedrock is generally in between 2-3m only. This unit has been downgraded as only marginally suitable for irrigation development because of restricted subsoil drainage in combination with limited subsoil i : y >v ■■ ! ••‘ depth. Irrigation suitability subclass: S . 3d ■y .* r V ij • 24• .,.u .••irr « t i I 'I <<l fl*v I Mapping Unit T„: Wevib soil seriesnearly level (l~ll slQPes.1 Approx. 89 i ha (or 9.|°6 of total area) Similar to Ttl above, but occurring on the nearly level upper river terrace summit and with 3-4m deep (sub)soil upto the bedrock. Brief Profile Description A. 0-23cm Black; moderately developed, very fine and fine, subangular blocky; strongly calcareous, cl AY • PH 8.4 . AB 23-70cm Black; moderately developed, coarse, angular blocky including wedgeshaped; strongly calcareous , cracking clav. PH 8.6. B u 70-150cm Black; moderately developed, coarse, angular blocky including wedgeshapeci; strongly calcareous, cracking clav.PH 8.2 Bk 150-160cm Black, with bright brown concentration of 6oft lime concretions; extremely calcareous, cracking clay, pH 8.4 This unit is moderately well suited for most (climatically adopted) crops. It is only somewhat downgraded because of difficult workability and restricted subsoil drainage. Irrigation suitability subclass: Sldw. 'z 5 • Mapping. Unit T : n asendabo soil .rl.es. strongly (6-7%) sloping rudlc Phase Approx. 6>/< ha(or >/<% of table area). Very deep, somewhat imperfectly drained, slowly permeable, slightly to highly calcareous, moderately alkaline, black, cracking siltv clav. It occurs on the transitional footslopes below H, sloping to the middle river terrace summit. It is covered by dense Acacia shrub vegetation and many surface stones of vesicular basalt. Description - Black; moderately developed, fine and medium, subangular blocky; slightly calcareous, siltv clay. PH 8.0. 63cm Black; moderately developed, coarse, subangular blocky; moderately calcareous, cracking siltv clav. ■ PH 8.2 .'.21' V IIP I 5 - .■ to to to Ito to i.. ... .. 63-108cm 108-165cm 165-190cm Black; moderately developed coarse, (sub) angular blocky including wedgeshaped; strongly calcareous (many lime pseudomycelia, cracking (silty) clay, PH 8.0. Black; moderately developed, medium and coarse, angular blocky, including wedgeshaped, strongly calcareous, cracking!s•lty) clay. PH 8.2 Black; as above, (silt'lclay PH 8.4 These soils are generally moderately well for Irrigation development; only downgraded of difficult workability and restricted drainage. This mapping unit however, suitable because of ste?p slopes and erosion suited because subsoil is not hazard. Mapping Unit Irrigation suitability subclass N,„ T„: Asendabo soil series very gently (2%_)—slQPlna. rudic Phase Approx. 10 ha (or 1}% ,f total area). Similar to Tlt above, 1 ut occurring at its foot and very gently sloping. This unit is thereforc moderately well suited for irrigation development as discussed under T„. Irrigation suitability subclass: S1(1. Mapp ink unil t„: AsendahQ sail series, nearly level (i_-l*% slopes!. Approx. 142Jha (or 14j“s of total area) Similar to T„ above, occurring on the nearly level middle terrace summit, but with no (or very few) surface stones. Brief Profile descript ion Black; well developed, fine, subangular blocky; moderately calcareous; silty clav. PH 8.0. 15-73cm 73-117cm Black; moderately developed, coarse, angular blocky including wedgeshaped; strongly calcareous cracking siltv clav. PH 8.2 Brownish black; modera'.ely developed, coarse angular blacky including wedgeshaped; strongly calcareous; trasKlna (silty) clav. ph 8.4. 1 ’' ’ d- 1 . “* •IP III t II I II I r H k i H k117-210cm Black; strongly developed, coarse, angular blocky including wedgeshaped; stronglycalcareous, cracking (slltY)clay, . PH 9.2. Likewise to the T„ unit, this unit is moderately well suited for irrigation development. Irrigation suitability subangular: SJ4, Mapping Unit I T14: Asendabo soil series, (3-4%) sloping_________ sgUL^wbed; phase Approx. 57 i ha (or 6"; of total area). Similar to sideslopes T„ above, but occurring on rather steep of the middle terrace with a few rock outcrops. 2-3m only. Depth to bedrock varies generally between } 1^) j' u This unit is only marginally suitable for irrigation development because of restricted subsoil drainage in combination with limited (sub) soil depth. And erosion hazard. i Irrigation suitabili' y subclass S14.. 1 Im d [y3 Mapping. Unit T,: Wevib soil series ngarlY level(<1% slopes) Approx. 70Jha (or 71"'. of total area) 1 *Ija *! 17-65cm 65-117cm Similar to T,,, but occurring on the lower terrace summit and with 3 to 5m. (sub)soil depth to the bedrock. Brief Profile Description Black; well developed, very fine, and fine subangular blocky; strongly calcareous, clav. PH 8.2. Black; moderately developed, coarse, angular blocky including wedgeshaped; strongly calcareous , cracking clav. PH 8.4. Black; strongly developed, coarse, angular- blocky including wedgeshaped; strongly calcareous , cracking clav. PH 8.2. J117-182cm Brownish black; strongly developed, medium, angular blocky including wed.ieshaped; strongly calcareous, with many soft lime concretions, cracking clav. PH 8.2. i.l82-195cm Brownish black; moderately developed, medium, subangular blocky, clav ■ PH 8.2. 27IS I• -X I i 8 This unit has been somewhat downgraded because of difficult workability and problems related to restricted subsoil drainage as moderately suitable for most (climatically adapted) crops. • rV ' Irrigation suitability subclass: S2dw This remaining 46 hectare (or 4.75% of total area) are covered by Kubsa village, which is located on 15.5ha of Vll and 28ha of V12 and 2.5ha of V13 soil mapping units. , 4 •' * A r’ ' X. <1 >**■1 ■Table 3: Showing hectarages (and % total area of all mapping Units occuring in the phase I, Bale Gadulla Area +------------------ | Kubsa Village: + ---------------- +--------------------- + | Hectares I % of total areal + I 1 1 +- 1 including Vll 1 V12 1 V13 1 15.50 I I 28.00 | 2.50 | I I 4.75 +- • Kubsa Village Subtotal 1 46.CO | I •+ 1 Hl 1 14.75 | 1.50 I 1 +- H2 1 15.23 | 1.50 •+ I 3.00% Vll 1 39.50 j 4.00 V12 1 68.00 | 7.00 Subtotal VI subland type I 107.50 | 11.00 V21 1 166.73 | 17.25 V22 1 47.00 | 43.75 V23 1 36.25 | 3.50 V24 V31 V32 1 Subtotal H land type 1 30ha | +■ 1 1 +• 1 +■ 1 1 1 1 + | + ■ /I. I _ 1 44.00 | 4.50 ——----------------------------------------+• Subtotal V2 subland type | -“--------------------------------------------+ | | 1 IVSubsoil V3 subland type 1 97.00 | | total V-land type ■ }| Ti*r- : 1 948.50 | I '*$? I Subtotal Tl-sub land ty I T21 _ I T22 | T23 I T24 | Subtotal -T2-subland type | ' |r. Vk/<AnjAvT3-subland type I • • ’» O• 1 1 pe | 1 1 1 1 +- 17.00 | 89.50 | 106.50 | 6.75 | 10.00 1 142.50 | 57.50 | 216 70 10.25 | 51.25 | 1.75 | 9.25 | 11.00 | 0.75 | 1.50 | 14.50 | 6.00 I v: •h- j\- ■ f• •&M<T6tal\T£land .• type b | < g-'.l > V'. • I ‘ Total^’area ■ * ■ •?’ * —— — 393 | 968ha +— —+ a 1 .• ,'* , -^ r • 28a5. IRRIGATION WATER QUALITY The study area is to be developed by using the water of the Weyib river. The quality of this water seems to be highly suitable for irrigation and no hazardous effects on soils are expected over its long-term use. As can be seen in Table 2, the Weyib river has low soluble salts and therefore no salinity problem and pH reading falls in the normal range. Toxic elements like sodium, chloride and boron are too small and will cause no problem for irrigated crops. Table 2, shows the chemical analysis of the Weyib river water. It was copied from the Korean report. Table 4: Chemical analysis of the '■’evib river irrigation water Chemical Conductivi ty (EC.) PH 0.0 8 dSm‘: 7,11 Cations (in meg/1) Sodium (Na') 0.24 Potassium (K’) 0.04 ■ Calcium (Ca") 0.36 Magnesium (Mg**) 0.16 Anions Lin meg/1) : .*• ■ ‘ • Chloride (C1-) Floride (F-) 0.08 ■■ Bicarbonate (HC-, 0.56 . ■■■■ Carbonate (CO,--) • ; r. Sulfate (SO,--) nill .•**.•.•*• *i Phosphate (PO.--) ■< .S’.-:.'.. Nitrate(NO,-) % Boron (mg/1) - , water analysis were c arried out at wrda's water labo ratory services.’UM <• | .ILAND EVALUATION FOR IRRIGATED AND RAINFED AGRICULTURE Some factors that effect land suitability for surface irrigation are permanent and others are changeable at a cost. Typical examples of permanent factors are climate, macrotopography, soil depth to bedrock and soil texture. Changeable characteristics which may be altered, may typically include micro-relief, vegetation, stoniness, •salinity, depth of groundwater and some social and economic conditions(e.g. land tenure, accessibility). The cost6 of necessary land improvements have to be estimated so that economic and environmental consequences of development can be predicted. In section 6.1 Land development requirements and limitations for surface irrigation are discussed and categories or degree classes defined such as for bush clearance, land levelling and removal of surface stones on the basis of an estimation of the costs for improvement. Table 6 summarizes the lan>l development limitations, requirements and classes of all the soil mapping units shown on the soil map. , In section 6.2 the physical and chemical properties of the three identified soil series (Kubsa-, weyib and Asendabo) are discussed and evacuated. In section 6.3 the potential (post development) .suitability of the soil units delineated, has been worked .out for a wide range of climatically suitable crops, both hfor irrigated and rainfed cultivation (see table 7 and 8 respectively). A,,',-. Then on the basis of these two aspects (land development classes and potential crop suitability) a general land evaluation for both irrigated and rainfed crop cultivation was made for all Lhe soil mapping units (see table 9). £•1 '1 Land—EfiVslQpment—Baquixeri ents and_____________ l^joiLatlons_____ Lax Surface Irrigation * ■ 1i V-; ; ;1',\-4>P-erm.an.ent limiting factors for irrigation development in?ithei^Bale-Gadulla (phase I), scheme, consists of 6teep, ■ ro’cj$y£hills and steep footslope; only, while the surrounding ■highyplateaus with steep escarpments confine the project to 'itlie'Eol'dftriver valley bottom with river terraces, only. Change able Limiting factor;; for irrigation development 'in'the Bale-Gadulla scheme include:a) medium dense vegetation cover, comprising mainly Acacia bushes and thornscrubs, on the river terraces only (=T- landtypes). b) Common to many surface stones of vesicular basalt, covering most of the older valley bottom (landtype v). c) Slopes and other topographic limitations ad a- Veaetation clearance In order to be able to construct the irrigation scheme, the area will have to be cleared of existing trees, bushes and shrubs. In the phase I area, only the river terraces of the T-landtype are covered by nedium dense low Acacia shrub vegetation with scattered trees. This area comprises about 393 ha (or 41% of the total phase I area) and the clearing reouirements of these T-mappina units are considered as low. Mapping units of the older valley bottom (V-landtype) are all cultivated and do not naed any bush clearance. ad b- Removal of surface. All the mapping units of the (gently) undulating or convex upper and lower part of the older valley bottom (V, and V, mapping units) are covered by common to many surface stone6 {mostly 10-30cm in diameter). These stones, however, do not occur within the soil profile, but they make the use ■ 'r.- '.of, mechanized agricultural equipment impracticable and will thus have to be removed. • ' ’ * ? . „ Manual picking of these surface stones, to clear an area , v. of'lOXIOmeters, resulted in a stone heap of about 1.125m’ and was'completed by 2 man in 30 minutes. Thus about 112m stones • per ha. may be cleared in 20x30x100 minutes = 100 manhours, or 13 mandavs. At a labour cost of 3 Birr per day, this will be about 40 Birr per ha. which is a negligeable amount. It may further be noted, that clearing the topsoil upto about 20 cm depth.' resulted in an additional stone heap of only 0.15 m’ per 100m’ (= 15m’ per hectare). 1 v’; ..Moreover, these topsoil stones, are generally smaller in size/riWith diameters ranging fiom 5-10cm. Therefore, these fewi'and small topsoil stones mry be left in the soil without causing?any problem. ‘V, ■ . 'U. ,’£4To‘ conclude,stone removal requirements low$f( even in the have^ariy influence I*project lands. are nil to very most dense stone cover units) and do not in the irrigajjility evaluation of the phase z ■ 31MIUJ, 0 * w n IB IB IB IB IB IBLand levelling After construction of the irrigation and drainage system, land levelling will be necessary ensure a proper water flow in moistening of the soil profile. To enable the irrigation accurate ‘ estimate of levelling for the furrow irrigation to the furrows and homogeneous engineer to calculate an requirements and costs, representative sample fields should be selected and measured in detail. In this qualitative classes report however, only very general of levelling requirements have been distinguished mainly on the basis of slopes (classes).r £Table 5: Preliminart land levelling classes, and related mapping units and their extent +---------------- .---- - ------------------ j.----------- - ■+ I I I + Soil Mapping Units +------------------------------------------+----------- | Land levelling I catagories I | Slope | Classes I% I Low grading/levelling | < 2% I requirements I V21 | I V32 I I I I I • +----------------------------------------- +----------- I I I I I I I V33 I T12 I T22 I T23 I +• T3 I Area | Total | ha | 166.75 | 57.00 | 21.00 j 89.50 | 10.00 | 142.50 | 70.25 | Subtotal +------ - ------------- | Medium | grading I +--------------------- I +--------------------- I High I grading I +--------------------- I •+------------------+--------------- | 2.5 - 3% | Til I I j T12 j V22 •+------------------+--------------- | Subtotal ■+----------------- +--------------- | 3.5 - 4% I I -+---------------- 1 V31 I V23 1 1 1 1 36.50 | 19.00 j 57.50 | | Subtotal 1 112.75 I ■| Excluded: I too,;Steep I or<rocky', or otherwise | j-not.’, suitable +—7—---------------------------------- +---------- | > 4% | j • - • 4 X- 1 Hl | H2 I Vll | V24 I T21 I | Kubsa Village 1 1 1 1 1 14.75 | 15.25 | 39.50 | 44.00 | 6.75 | ----------- + % of | Total j I ------------+ 17.25 | 6.00 j 2.25 I 9.25 | 1.25 | 14.50 | 7.50 | ---------------- + 58.00%| 1.75 | 7.00 | 4.75----I ---------------- + 13.50X1 ---------------- + 3.50 | 2.00 | 6.00 | ------------ + U.50X| -----------------+ 1.50 | 1.50 | 4.00 j 4.50 j 0.75 I 1 46.00 | +■ +---------------------- | Subtotal Grand Total ■+--------------------- — 4.75 | ----------------- + 17.00X1 100X1 ----------------- + *v !.■i s9 d. Land Development classes In summary of the above, it may be noted, that the medium dense vegetation cover of Acacia shrubs (on the river terraces) as well as the common to many surfaces stones on most of the cultivated older valley bottom surfaces, both require only low development efforts (and costs) and are therefore allowed in land development classes DI. Thus the only remaining factor of importance for the land development classes in this phase I project area, is formed by the different slope classes. Of this latter, the low grading category has been allowed for in land development class 1, and medium grading in land development class 2, while high grading will come into land development class 3 and the remaining units will be excluded of any irrigation development. In 6 table below, the type of limitation and their development requirements as well as the land development classes have been summarized foi all the soil mapping units. 6.2 £y-AlUA.ti£>n q£ the soils fertility) r‘ A . » ,» .1 * * -■ I *' ■ ’•** • \,r. I < About 938 hectare (or 97% of the total phase I area) is covered by very deep, somewhat imperfectly drained, black to brownish black, moderately to (very) strongly alkaline, medium to highly calcareous, non-saline, (occasionally sodic), cradling clav soils. On the basis of only minor variations in soil colour (either black or brownish black), presence or absence of a calcic horizon within 125 cm of the surface, soil texture, (being either silty clay with 31-53% silt or clay .•- “J with less upper and 8.6 which which is different than 32% silt), or soil reaction (PH of the lower subsoil varying either in between 8.0- is moderately alkaline, or in between 8.4 9.4 •, > ‘•i <■ i distinguished. strongly to very strongly alkaline), three soil series have been tentatively They are named Kubsa, Asendabo and Weyib ■» A J ■. -k i. -V. soil series and respectively classified as Chromi-Hypo- CalClC-, felli-Hvpo-Calcic. and pelli-Eutric Vertisols. 5. The physical properties of these dark-coloured, J-cracking clay soils are moderately good. •7.. ‘sty T : l ■ :$ • ■ • They are ----- - —- - band somewhat 5 Ar -.. i :■ ’;;.slow to very ib.£-;obtained from expected. difficult to work for seedbed preparation imperfectly drained with (most probably) slow permeablities although the values the field tests are somewhat higher than These values vaiy in between 0.24-0!73 meter •Ber -day, which is moderately slow to moderately rapid. c I These relatively high values may be insufficient pre-wetting and thus not shrinkage cracks. 34 the result of closing all the / * * • • • 1 • • T----------------------- •—I M M ni m « l I l I I I iTable (: Land Developient Liiitations, requirements and Classes, of all soil Mapping units in the Phase I, Bale-Gadulla area 1 1 Soil 1 Type of Di•gree of tliltitions | Developient Bequireienls ._ _ _ _ _ . . . . . . . . . . . . . . . . . . . A. . . . . . . . . . . . . . 1 I Land 1 Developient- Area I 1 Nappin I Units g I Topograph; f| Vegetation Btsb | Stone | 1 Slopes 1 | Surface | Stones I Levellingl • Reioval 1 Cle arance| 'cl earance I Classes | 1 H’ 1 1 1 1 1 |V12 I 2.5-3 I Cultivated I Nany I Hediui | None I Lew | D2L 1 69.30 | 1.00 | |V21 I 1.5-2 • I Cultivated | Nany 1 Lou | None | ton I DI 1 166.15 | 11.25 I |V22 I 2.5-3 I' Cultivated I Many I Nediua | None | Lou | D2L |V23 I 3.5-4 > I Cultivated 1 Many 1 High | None | low | D3L |V31 I 3.5-4 |V32. ;l <2 |V33 1 <2 |. Cultivated | few-none 1 High ' I .cultivated 1 few-none 1 Lev | None | none | None | Sone | D3L I 47.00 | 4.15 | | 36.25 | 3.50 | | 19.00 | 2.00 | I Cultivated I Many 1 Low | None |1 low | DI 1 57.00 | 6.00 | | DI 1 21.00 | 2.25 | |T11. J 2.5 l-Acada Shrub| Tea I Xedloi | Low 1 low I D2L | I 17.00 | 1.75 1 |T12 .’IH-i.s 1.Acacia Shrub) None 1 Low | Lou I None | DI 1 39.50 | 9.25 ) |T22 12.. • I Acacia Shrub| Many IT23 ■1 .1-1.5 1 Acacia Shrub! None 1 Low I Low 1 Sone 1 01 | Lou I Low 1 lov 1 DI 1 10.01 I 1.25 | 1 142.50 | 14.50 | >|T24 in 1 ! ■ 1 ‘ I 315-4 . 1 <1 ' | Acacia Shrub| V.few r.0| High |*Acacia Shrubl None 1 lot I Low | Low I D3L 1 Low 1 Note ' DI 1 57.50 | 1 10.25 | 6.00 | 7.50 | Total area to be developed included/ because not suitabl e for irrigation 'development: Hl, H2, Vll, V2I T LI and ktsa Village 1 301.15 1 • 3211 V 1 155.15 1 ■ 1 1 > rv A 4. ,.* - I ■ Grand Total i 356 1 k: ................. 4 35■ ■ i ?The same can be said o£ the relatively high bAS-ic. infiltration rate_s measured in the field, varying mostly in between 5.8*7.3cm per hour. These values indicate moderate to marginal suitability for gravity irrigation. Total available moisture measured on undisturbed core samples of 4 different soil profiles vary in between 183-350mm over 1 meter which is rather hlnh. (silty clay to clay textures usually show values of available moisture in between 180-250mm only). Top soil structure of these soils, however, are generally very good, fine to medium size, subangular blocky and friable when moist. The chemical properties these soils are generally good except for their soil reaction (pH) which is moderate to (very) strongly alkaline (pH 8.0-9.4) causing limited availability of micro nutrients and occasionally sodicitv problems, which will require addition of gypsum. At higher pH (>8.5) values, availability of phosphorus also decreases in the presence of calcium andt toxicity is common in sodic soils (pH>9.0). Cation Exchange capacity (CEC) is high to extremely high (62-81 meq/lOOgr soil) and exchangeable bases of Ca and Mg are very high and of K high to very high and base saturation % is very high. Exchangeable sodium percentage (ESP) is mostly below 15% but occasionally 27-39%, which may cause future physical problems through clay deflocculation. These high ESP levels may have deterious effects on the structural stability of these soils and their physical response when water is applied, especially since they contain expending type of cloy minerals. The presence of excessive amounts of exchangeable sodium promotes the dispersion and swelling of clay minerals. The soil becomes impermeable to both air and water. these soils will thus require gypsum application without which 50% yield reduction may occur. Organic carbon content i*? high in the topsoil (2.4- 3.3%) and medium in the subsoil (0.7-2.0%)., Nitrogen is high to very high in the topsail (0.15-0.86’%) and medium to very high in the subsoil (0.10-0.98%):. Available phosphorus varies between 76-925 ppm (or 11.4 to 138.7 kg per ha) which is slight to high. i i 36I i I I •» j J A6.3 Crop Requirements and Crop Suitability Qf—the—soils—end the soil mapping Units 6.3.1 General Description of_______ suitability—glasses—and subclasses Most crops are tolerant of a wide range of soil conditions. Varieties of some crops can be bred, to suit (or tolerate) particular soil environmental conditions. Crop yields also depend greatly on management: by good management or use of special techniques, a skilled farmer may be able to produce satisfactory yields from a soil relatively unsuited to the crop. Good crops can sometimes be obtained from 'poor' soils too, in years with favourable weather. Besides, the suitability of soils for irrigated crops intends to be independent of rainfall characteristics. ; i The crops for which the suitability of the soils has been rated here, are those adapted to the;climatic environmental (altitude) conditions (see figure 7). The land suitability classes quoted in table 7 (for irrigated) and table 8 (for rainfed) are defined as follows: z ■J, JIIt •» ? • • 51 52 53 N1 N2 Y.X Highly suitable Moderately suitable Marginally suitable Presently not suitable Permanently not suitable The subclasses are indicated by using L.< -. -*; a ' ”r. 't latter suffixes for the major suffix being the most important limitations: limitation. lower case the first They are: c climatic conditions not well suited to (temperatures too low) the crop y<9. >■. restricted rootability - limited depth to bedrock rock i outcrops. • .Very steep slopes .?;■ • • ■V • .' 4 •?> ; • P' / I ■' »' •< «. • I - ’ll ’ 'r ^v(sheet) erosion hazard (moderate steep slopes) workability for seedbed preparation and/or too heavy topsoil causing poor aeration or prevailing peg penetration (groundnuts) and/or causing losse at harvesting. W • ,J4- tt• « Z v. s' 5 ; •y \ »- d problems due to restricted subsoil drainage or poor aeration, but at least 3m deep upto the bedrock. These I • soils may be artificially improved for Instance by i .> ditches of 1 m. or more deep at frequent int ervals r. ! . I «■ 37 ■« -,-r • ?*• T > .• •.■ 1 ■ •'3815 V ... d' a; a = = restricted subsoil drainage as above and in combination with limited soil depth (e.g 2-3m depth only) as a result of which the groundwater table will build up rapidly under irrigation, to reach within the rootzone. p = only for rainfed: rainfall restricted or too erratic, hazard of perodic drought (800-1000mm annual rainfall). Soil reaction (pH) too high (=alkaline) and/or even sodic. In table 9 the dominant suitability for most of the climatically adapted crops is given for all the soil mapping units; both for irrigated agriculture as well as for rainfed. Also the extent (and % of the total area) i6 given for all the suitability subclasses. * -f 6 3.2 Major requirements of_______ t 'is_CfSPS__ ShQWD—In—tllfi—CTQP suitability tables Maize has relatively high moisture and nitrogen requirements and a shallow rooting system (mainly within 40cm). It i6 killed if the rootstone is waterlogged for more than about a day. It tolerates a wide range of soil reaction. With rainfall less than 800mm, in the Bale Gadulla area, the dark coloured cracking clay soils of this area should not be placed higher than suitability class 3 because of drought hazard during the growing season. Thus suitability subclass (P for low i :,C i* •j ,i *> J . >i'•r-y rainfall), provided that no other limitations are present which require them to be placed in a lower class. For irrigated conditions these soils should not be rated higher than class 2, because of difficult workability and \r- '■? restricted subsoil drainage: suitability subclass i , and y; .«■•* i •,t •X’ < * *A ,*i! ( 1 v" n 4 / >. •/ •y • v. rv S •h whenever the subsoil (upto the bedrock) is less than 3m. deep, they should not be rated higher than class 3: suitability subclass S>4., (d1 = risque of rapid build up of ground water table within the root zone).. Wherever these soils are sodic they should also be • // ■A' rated as class 3: suitability subclass ’.< 1 *jTl Wheat is deep-rooting, has only a moderate moisture ?-.x? z A- 1, . ;a. requirement, is tolerant of short period wetness in the .rootzone (but not sustained water logging) and tolerates r>'j.a-,wide range in pH. »v. A / •n.< t - «r ' . v.‘ w______ M J''" be 9rown • 7 J*h’ &t grown in the rainy season is susceptible to e J r •2^5 J .»• ■ -/Sr? ease an<^ difficult to weed and is not recomc.ended, at ^present. Therefore suitability subclass (for rainfed): Ni». For commercial production, however, it requires to ________ ____ irrigation ni the drv~season? I v 1 t • : fl. i. r mi/ - ■ B ». 39 Ml’-: >r < »- i• i .,i * ’ r ■1' I. ....................................................... ........... WR.WTrrrrr—?■ .a«"M.il > *U'>‘ * A / •'' Iconditions): & . a For Sorahum■ any soil receiving less than. 800mm, annual rainfall, should not be placed higher than class 2, because of drought hazard during the growing season, under rainfed cultivation. Thus suitability subclass: So under irrigated conditions, the dark-coloured. Cracking clay soils, can be placed in class 1, where there are no other limitations, such as wetness or depth. But because of their somewhat imperfect interal drainage, they are rated in suitability subclass Slt. Rainfall is too low tn this area, to provide adequate moisture for rice during the growing period and these soils are thus rated as not suited for rice under rainfed. Suitability subclass: tL, • But under irrigated conditions they may be well suited. For groundnuts temperature conditions are rather too low, and with annual rainfall below 800ram, these soils should not be placed higher than class 3. Besides, the heavy topsoil textures of these cracking clay soils are preventing the pegs fiom penetrating while clay topsoils are also unsuitable since this increases losses during harvesting. Therefore the suitability subclass under rainfed will be , provided there are no other . ■ limiting factors to put then in a lower class. Under irrigated conditions they mc.y be placed in class 2 or suitability subclass Yields of beans are riduced by short-periods of water logging. Therefore, these somewhat inperfectly drained, cracking clay soils should not be rated higher than class 2; or suitability subclass Sldw, for both, rainfed and irrigated cultivation. 40* rt ■ •Potatoes are best grown on an acid soil, while the somewhat imperfectly drained cracking clay soils should not be placed higher than class 2, since potatoes are very sensitive to waterlogging for more than 1-3 days in the surface layer. Without irrigation potatoes can only be grown in the rainy season, but since annual rainfall is less than 800mm, they should not be rated higher than class 3, or suitability subclass With irrigation available, it is possible to grow three crops in the year (although preferably not on the same land, because of disease build up) and these strongly alkaline clay soils can thus be placed in suitability subclass: S,tf.. Tomatoes do not well under alkaline conditions and the plant is not frost tolerant. With less than 800mm annual rainfall, these somewhat imperfectly drained clay soils should not be rated higher than class 3, or rainfed suitability subclass:SAad while under irrigation they may be rated as suitability subclass S„.. Kenaf is sensitive to water logging and to ensure even fibre quality, irrigation is necessary in this area with less than 800mm annual rainfall. For under rainfed conditions these soils are thus rated as not suitable for Kenaf or suitability subclass . But for irrigated conditions these somewhat imperfectly drained clay soils may be rated not higher than suitability subclass Dark-coloured cracking clay soils can generally be placed in class 2 for if artificially drained to 1 meter depth and irrigated. However the high altitude (above 1800m) is another limitation downgrading these soils as class 3, or suitability subclass provided there are no their limitations. Under rainfed these soils are not suitable because of low rainfall, or suitability subclass •. For Bflnana£.> these clay soils can be placed in class »-if they are drained to at least 6 0cm. but temperatures ■^;>’?are. rather too low, for which reason they have been • U:/'downgraded as class 3, or suitability subclass And - -’'under rainfed as suitability subclass s,„. *• For Coffee and Tea, these heavy clay soils would . .j, -not be placed higher than class 3, because of restricted permeability and aeration. 411 -JI i i I i i i Also the calcareousness and higher pH (even sodicity) is another limiting factor, and rainfall is too low (should be above 1300mm) . So they are not suited for rainfed cultivation, or suitability subclass: • But assuming irrigated conditions, suitability subclass may be provide there are no other limitations. For Tobacco temperatures are also rather too low and so is the rainfall. therefore rainfed suitability subclass N»... But for irrigated conditions these some what imperfectly drained clay soils may be rated not higher than suitability subclass since it is very intolerant to water logging. Cotton is tolerant of moderate to strong alkalinity (60 long as this is not accompanied by impeded drainage which is the case with the dark clay soils). It requires higher temperatures. With rainfall of less than 800mm annually, these cracking clay soils can not be placed higher than suitability subclass . Under irrigated conditions these somewhat imperfectly drained clay soils should also not be rated higher than class 3, or suitability subclass Because of requirements, and of these black cracking sunshine and hot temperature not being tolerant to water logging / clay soil should not be rated higher than class 2 for Sugarcane. And because of annual rainfall being less than 800mm, these rated for under rainfed conditions subclass only. clay 6oils are in suitability Under irrigated conditions these suitable for sugar cane cultivation, clay soils are if they are adequately drained, by means, of ditches 1 meter or more deep at frequent intervals or cultivation of the crop on cambered beds. irrigation suitability subclass: II I I - ■ ■a »■" Table 7: Irrigated Crop Suitability of the Bale-Gadulla (Phase I) area -----------------A I Soil Mapping Units; Soil series, variants anc phases I ■4.........4........... 4........... 4........... 4........... 4........... .. ........... ........................... .. ........... 4............ 4........... 4............ 4.......... 4 I Hl | H2 |Vll | V12 I V2I | V22 | V23 | V24 I V31 I V32 I V33 I TH I T12 I T’l i T22 I T23 I T2I I T3 | Idalze ivheat I Barely iSorghui jl2rs|I2i (Xled(S3d’ifis2dw /iRice |N2rs|l2j Idle |S2e 4...........4 4444444444 — 4 |Groundnuts|N2ri|]l2l.. (S3ew|S2cw iBeans [12rs|M2s.i'|S3ed|S2d« 4.4....4.................................... 4.....4-------------------- .................. 4.------ .4. .......... 4........... 4----- --4---------■*---------4--------- ♦---------4............4 |H2rs|H2l |Hled|S3ad |S2dw |S2dw |S3ed |Nled |S3ed |S2d« |s3ad IS3d'w|S2dw iHled |S2dw |S2dw |33d'e|S2dw | |I2rs|H2t |Hled|S3d'a|S2du |S2dw |S3ed |Hled |S3ed |S2dw |s3da |S3d'v|52dw Idled |S2dv |S2d» |S3d'e|S2dv I | . N-2. .r.s.-|l-2-s- - - - - - -|-H- i-e-d- -| S- -3-d*x..|.S.2...d-w- - - - -|S- 2- d- w- - - - |-S-3-e-d- - - -|-N-le- d- - - - -|S- 3- e- d- - - - |-S-2-d-w- . ..|S. 2..d. w. .. ...|S- -3-d-' -|S- 2- d- w- - - - - - -I-d-le- d- - - - -|S- -2-d-v- .... |.9.2..d.v.. . |S3d'e|S2d» | |S2dw |S3ed Idled |S3ed |S2dw |S2dv |S3d' |S2dw (Hied |S2d» |S2dw |S3d'e|S2dv | |S1 |S2e |S3e Idle |S3e |S1 (SI |32r |31 Idle |S1 |S1 |S3re (SI I 444--------------------------- 4 |S2cw |S2cw |32cm |S3cw |S2cw |S2cm |32cw |S32v |52cw |S3ew |52cw |S2cw |S32w |S2cw| |S2dv |52dw |S3ed |S3ed |S3ed |S2dw |S2dw ]S2dw |S2dw |S3ed |S2dv |S2di |S3id |S2dv | iSoya Seans(H2rs|d2t ■: |S3ed|S2dw |S2dw |S2dw |S3ed |S3ed |S3ed |S2dw ISZdn |S2du |S2d» |S2dw |S2dw |S2d« |S3ed |S2dv ISaffloxer |M2rs|H2s_. |S3ed|S2dw |S2dv |S2dv |S3ed |S3ed |S3ed |S2dw (S2dw |S2dw |S2dw |S2dx |S2dv |S2dw |S3ed |S2d* I -ISunflower |N2rs|Xh ’ |S3ed|S2dw |S2dw |32dw |s3ed |S3ed |S3ed |S2dw |S2dx |S2dw |s2d< |S2aw |S2dw |S2dv |Sled'|S2dw | (Potatoes |X2rs|I2s ■ |S3ed|$3d'a|S2da |S2da |S2ed IS3ed |S2ed |S2da (S2da |S3d'a|S2da ISJed |S2da |S2da |S3ed' |S2da | |?oiat:es 1N2rs|W2s,:|S3ed|S3d1 a133da |S3da |S3da |S3ed |S3da |S3da |S3da |S3d'a|S3da |S3-d |S3d> iSlda |S3d'a|S3da | |Lenaf |X2rel»2s-'1s3ed|S2d |S2d lS2d |S3ad !S3ed |S3ed |S2d lS2d |S2d |S2d |S3ed |S2d |S2d |S3ed |S*d I ...4.— 4................. 4 —.4 4 4........... 4 4 4 4 ‘ 4 ‘ 4.......................... * 4 4 4 icitrus. . . . . . . . . |H2rs|N2s |S3:d|S3cd. . . . . . . . . . . |S3cd |S3cd |S3cd. . . . |S3cd. . . |S3cd. . . |S3cd. . . | S3cd. . IS3cd. . . |S3cd. . . |S3cd |S3cd IS3cd. . . . |S3cc. . . . . . |S3cd| • lEaninas |H2r$|d2s |S3cd|S3cd |S3cd |S3cd |S3cd |S3cd |S3cd (S’cd »S3cd lS’cd lS3cd |$3cd lS2:d I'Jcd lS’cd IS3:d I ''4: — .•4-.—.4-----4---«4..................... *........... *........... *............4........... 4........... 4........... 4........... 4........... .. ......................... •............ •.........................................' :’r iCoEfeeX*. JH2rs|d2s :^|Tei^Vm:rs()i2s |Nlda|Nldra|S3da |S3da |S3da |S3de |S3da |S2da (Hida IXid'aS’da |Slde ISlda Idlda |dld'a|S3da I |Hlda|illd'a|S3da |S3da |S3da |S3de |S3da |S3d« |Nlda (Xld alSSda |S-de |S3da Hilda IHla'a'.Slda ; |"obaccoV.*;]Xirs|l<2s |N2s |S3dc |S3dc |S3dc |S3dc |N2s |S3dc |S3dc |;3d: |S3dc |S3d: |X2s |S3dc |S3dc fS3dc |S3dc ; 4..-..4. ^jcotWn^’-ixirsXxh IS3ed|S3cd |S3cd |S3cd |S3cd |S3ed |S3cd |S3cd ! S3cd ^|Sugarmahe|i2rslN2s..m3ed|X2d' |S2cd |S2cd |S2:d |S3ec |S2cd ISlcd |S3ed |S3:d |S2cd |S3ed isle: lS3cd |S3:d |S3cd I52cd |r.d' |S2cd V.Y •r‘- ' ■* r >» Table 8: Rainfed Crop Suitability of the Bale-Gadulla (Phase I) area 4 I i I Crops 1 I Soil Mapping Units: Soil series, wauanrs and phases 1 1 1 •t. . . . . . . . . . . . . . . . ♦- - - - - - i Hl I H2 I Vll | V12 | V21 1 V22 | V23 | V24 I V31 | V32 i V33 Til I T12 | T21 1 T22 1 T23 | 724 I 73 | (Maize |X2ri|X26 |NlSe |S3pe |S3p Iwheat |X2rs|X2s |MlC |N1C |Hlc |Barely . |X2rs|X2s ,|S3pe |S2pe |S2p |S3pe |S3p |S3p |S3pe |S3p |S3p |lllc |XlC |Xlc INlc IXlc |Xlc |52pe |S3d' |S2p |S3pe |S2p |S2p |S3pe |S3p | IXlC |Xlc | |S2pe |S2p | 1Sorgbua |X2rs|X2i |93pe |S2pe |32p |S2p |S2pe |92pe |92pe |S2p |52pe |93d' |92p |S3pe |S2p l92p |92pe |S2p | iRlce |X2rs|W2s |X2pe |M2p |X2p |53p IS3pe |S3pe |S3pe |53p IXlc |Xlc |XlC |XlC |Xlc |S2p |S2pe |S2pe |S2pe |S2p ♦. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . f. . . . . . . . . ♦. . . . . . +. . . . . . . . ♦. . . . . . . f. . . . . . . . +. . . . . . . |X2p |X2pe |X2pe |X2pe |X2p |-I2pe |X2p H2p |X2pe |I2p II2P |I2pe |!2p 1 iGroundnuts|I2rs|M2i |Hlsv;|S3pv |S3pw |Beans ;V|X2ri|X2«,' |S3td |S2dw |S2dw ISoya.B€aQs|X2rs|N2s?'lM2ps |S3pd |S3pd |S3pv |93p» |Xlsv |S3p« |S3pv •'|Sifflower|X2rs|l2is^.|S3sp'|S3pd |93pd /J Sunflower.|X2rs|X2j JS3sp |S3pd jPotatoes','|X2rs|X2s' |S3ps |S3pd ■[Toiatoes|N2rs|N2s |S3ps |S3pd '■'IXenafv;' |B2r«|N2s\<|X2ps |N2p |S2dw |S3pd |93pd |53pd |S3pd |S3pd |S3pd |S3pd |S3pd |N2p |H2p |33ed |S3ed |S3ed |S3ps |M2pc |S3ps |33pe ISJps |S3pe |S3pe |S3sp |S3pe |S3pe |S3ps |S3pe |S3pe |S3ps |S3pe |S2dw |S3pd |S3pd |3epd |S3pd |S3pd IX2p |S3pd |S3pd |S3sp |S3pd |S3pd |S3ps |S3pd |S3pd |S3ps |M2p |X2ps |N2p 4 *"T'".*‘4"“‘iT"’"4. . . . . . . . . . . . . . . . . . . . . . . . 4. . . . . . . . . 4. . . . . . 4. . . . . . . . 4. . . . . . . . . . . . 4. . . . 4♦. .. .. .. .. .. .. .. *t.. .. .. .. .. .. .. .. 4♦. . . . . . . . . . . . . . . . . . . 4. . . . . . . . . . . . . 4. . . . . . . . 4. . . . 4 |X2p 4 ........ |N2cp |N2ps 4 ........ |N2cp |X2p 4 jCitrus.<; ,|K2rs|X2$ ■ |X2cp |M2cp iBananu. |I2rs|X2s |S3cp |S3cp ...... |X2cp |X2cp |S3c? |S3cp ....... |N2cp |S3cp |S3cp |S3cp |H2cp |H2cp |M2cp |X2cp |XZcp |X2cp |X2cp |X2cf |X2cp | |S2cp >S3cp |S3:p |S3:p |S3ct |53cp IS’cp |S2cp lS3cp | 4 ......... 4 ...... 4 ........ 4 ........ 4 ........ 4 ....... 4 . . . . . . . . . . . . . . . . . 4. . . . . . . . t. . . . . . . . +. . . . . . . . . . . . . . . . . . *—. . . . . . . . . . . . . . . . . . . . . . . . . . . ’ | Coffee/--|12rs|X2s |N2pa ;n2pa |X2pda|X2pda|X2pda|S2pda|X2pda|X2pda|X2pda|X2pda|X2pda|X2pdalH2pda|X2psa|X?pda|X2pla| <|Tea.;.|X2rs|N2s- |X2pa |N2pa |X2paa | N2pda | X2pda|X2pda| N2pda I N2pda I II Zpda j X2f<1*|N2pca J NlFda i KlFda I HLfci |I2pda | X2pda | 4^iTobijCCQi^lXZnl^lllps |X2pc |X2pc |X2pc |X2pc |X2ps |X2pc |X2pc |«pc |I2pc |X2pc |X2ps |X2pc |X2pc |X2pc |I2pc | . . . . . . . 1. . . . . . . . ♦. . . . . . . . ♦. . . . . . . . *. . . . . . . . ♦. . . . . . . . ♦. . . . . . . . 4. . . . . . . . . . . . . . . . . . ♦. . . . . . . . ♦. . . . . . . . 4. . . . . . . . f. . . . . . . . . f. . . . . . . . 4. . . . . . . . f. . . . . . . . ♦ -z>| Cotton r-X'i _ '/.L^'?^3Cl!?3s' !?3c? !S3c? !s3cp !s3cp ls35c ls3cP ls3:p l53cp lS3cp IS3CP |S3sc |S2:p 'Slop |S3cp |S3cp '6.3.3 Major Differences in Land Evaluation for Irrigated and rainfed agriculture As can be seen in table 9 below, all class 2 land for under irrigated conditions have been downgraded to class 2 to 3,. mainly because of low annual rainfall, especially for as far as the non-cereal crops are concerned, but also for wheat (see table 8, above). On the other hand, somewhat steeper sloping mapping units, which were considered not suitable for gravity irrigation development have been classified as marginally suitable for under rainfed conditions . Thus as a whole about 92.25% of the total area is mostly only marginally suitable for rainfed, while Introducing irrigation would classify about 60.5% of the survey area as moderablely suitable for crop cultivation.- -1 JTable 9: Coiparing general land evaluation for irrigated and rainfed cultivation of the Bale-Gadulla, ?bre I, areas Irrigated Agriculture I Raiofed Agriculture •4. . . . . . . . . . . . *. . . . . . . . . . . . . . . . . 4 •4 I Rainfed *......................... -4................................ I Irrigated I Suitability I Subclasses I Soil | Extent 1 Soli 1 Mapping I Units I Extent | 1 Mapping |- 1 Units | ( bUlLdD-lltj Ha 1 1 of I Subclasses 1....................................... 1 I ;<a 11 1 of 1 1 1 1 |Total areal 1 1 (Total a real :........ ......... a |S2d» |V21 1 166.75 | 17.25 |S2-3pd IV21 I 165.75 | 1 17.25 | |S2dw |V22 |S2dv 1 47.00 | 4.75 |S2-3pd IV22 47.00 1 4.75 | |V32 1 69.50 | 1 57.00 | 6.00 |S2-3pd |V32 I 57.00 1 6.00 | |S2dw IH2 9.25 |S2-3pd IT12 1 89.50 | 9.25 | |S2dv IT22 1.25 |S2-3pd IT22 I 10.00 1.25 | 1 S2dw IT23 • 1 112.50 | 1 10.00 1 14.50 |S2-3pd IT23 I 142.50 | 14.50 | |S2dv ; IT3 1 70.25 | 7.50 |S2-3pd IT3 I 70.50 | 1 7.50 | 4—— I Subtotal S2 1 583.00 | SO.501|Subtotal 32-3 I 583.00 1 50.5341 ♦ •••. . . . . . . . . . . . |S3d'a |V12 1 66.00 | 7.00 |S3pe IV12 1 68.00 1 7.00 1 |S3di |V33 1 21.00 | 2.25 !S3pe IV13 I 36.25 1 1 3.50 1 |S3ed |V23 1 35.25 | 3.50 |S3pe !V31 | 19.00 1 2.00 1 |S3ed |V31 1 19.00 | 2.00 ISJpe IT24 | 57.50 1 5.20 | |S3d'e |T24 1 57.5C | 6.00 |S3pe 1 39.50 1 4.00 1 IS’i'w ;Tli 1.75 |S3pd’ IV11 •R•• •4• 1 r.oo 1/5 1 J............ 1 17.00 | .................4-- ................. 4 ISubtotal S3 1 218.75 | 111 22.5t|S3pd 1 |V33 1 IV24 I 21.00 1 2.25 | * . . . . . . . . . . . . . . . . . . . . .4........ -4- ........4 1 4 11 ?|S2S$.: |H1 1 14.75 I 1.50 I Sips I 44.00 1 4.50 I |H2 1 15.25 | |V24 1 44.00 | |T’l 1 6.75 1 |V11 1 39.50 | 4.50 ♦. . . . . . . . . . . . . . . . . . . . . .1........ -4.................. A-. 1.50 |S3ps IT21 1 6.75 1 0.75 | •qitled^ ; >|Hled^ ''iNlett' .........a 0.75 Isubtttal 4.Q0 4-.---....... .....- - - - - - - - - ------- - - - - - ... *-• ------ - - - - - .a S3 I 309.00 1 • I’ 1 1 1 ■ I ■: 1 1 1 |N2sr |M2i 13! I 14.75 1 1.50 1 sh: 1 15.25 1 1.50 ! I subtotal N 1 120.25 | 11.25 |Subtotal IN I 20.0? • 3v: 4. IKubsa Village 1 H| 4.75 IKubsa Villa.•ftl I 46.00 1 4.754! IGraad Total 1 956 Ha | 100.octi I 96 3 F.a ’.'■Oil - >■II j * n n I*REFERENCES AID - USDA 1988, Australian June 1987 Agricultural Consulting and Management Co. PTY, Ltd. Brammer, H. 1975, FAO FAO FAO FAO 1976, 1977 , 1979, 1978-81, FAO ’’ • ■■ ■_ ■ s • j FAO/ISRIC \ .<• -C-p <■ < - Michael, . r .. , A.M. w • y > 1985, 1989, 1974 , 1990, < Kazmin,V r. ’ — * f. Munsell’ Oy.ama, H. & Hv-Tekera. • *> *. *}« ■ ' ■< <>USDA 5 ? ' ..^V’ - i, )< _ • ■ % 1972 , 1954 , 1967 , 1951, Key to soil Taxonomy, by Soil Survey Staff, SMSS Technical Monograph No. 6, Washington, D.C. Assessment of Agricultural land suitability in South-Eastern, southern, South-Western and and Western Ethiopia, Vol, II- Mena-Berbere, LUPRD, Ministry of Agriculture, Ethiopia. Crop suitability: Technical Guide No. 7, Land Use Branch, Dep. of Agric, Mt. Makulu, Zambia, A Framework for land Evaluation, Soils Bulletin, No, 32, FAO, Rome. Guidelines for Soil Profile Description, 2nd Edition, FAO, Rome. Soil Survey Investigations for Irrigation, soils Bulletin No. 42, FAO, Rome. Reports, of the Agro-Ecological Zones project, World Soil Resources Report, No. 48/1. Guidelines: Land Evaluation for Irrigated Agriculture, Soils Bulletin No. 55. FAO, Rome . FAO-ISRic Soil Data Base (SDB), World soil Resources Report, FAO, Rome. Drainage Principles and Application, III Survey and Investigation, Wageningen. Irrigation: Theory and Practice. Vikas Publishing House, PVT LTP, New Delhi. Geological Map of Ethiopia (scale 1:250,000). Geological Survey of Ethiopia, Min. of Mines, A.A. Munsell Soil color charts. Revised Standard Soil Color Charts. Soil Survey Manual, Agr. Handbook No. 18, USDA, Washington.mm > > > 11 -rr j4 —rri'.- . r»- - * * Iw ;V- • >• - r . > ;J:*'*’ • ' V. .r •■ USDA Y*i *>- 1978, Bureau of Reclamation, Drainage Manual, Denver. WRDA 1990, Soil and Land Suitability of the Bale- 4.-. r ;May . y. Gadulla area, Bale Region - -■ r* . - 4 WRDA/FAO 1 March 1992 - » - • .•-•»■ Agro-Socioeconomic Survey for proposed irrigation project at Bale-Gadulla K ,* s Zimmerman, J.D. 1966, (unpublishe Irrigation, New York. d). John Wiley & Sons, V. ,/» SI $ r I ■> ■•. •• l>> ""I J 481RAppendix I "^.■Z . I............................... '•VI .A’ • if* »s^l>-’i«sa^-.7 I - i 1 iProfile BAG001 »"’t: SOIL.PROFILE; OESCIIFTIOM Sheet/Gridi^/IBOOM S3LSE Location '^Hear Bench aark -13. Survey Area" : Bale Gadulla Author(s) : Lucas Van Sleen Girua Asfau Nelese Kuasa Classification FAO: Calcic Vertisol(IBOB) Chroaic Vertisol I’Ilk) - sodic phase ST : Udic Chroaustert, clayey, aontaorriloniti.(calc.),, Coord Elevation: Date : H ) -06-A5 E kO -22-10 1192 a 11/02/92 \ local series : lubsa Soil series Soil Cliaate Topography Eleaent/Pos Flooding*/ Land Use / Vegetation Species land Fora: valley Slope : Micro Top: even 2 - Il convex ■ « i ustic isotheriic gently undulating interfluve- upper slope nil Urban short grassland •"* Parent Material: in situ weathered over volcanic ash Bock Outcrops : very few - Surface Stones : coaaon stones Erosion: nil and nil * * . • .• • • • Drainage-^iaperfect, internal drainage: very slow, external d sinage: rapid Vatertible:-not observed > Moist Condrdry 0 -;H0ci Huaan Infl/fertilizer application Reaarks: Grasscover: >109 - derived froa basalt Sealing/Crasting: nil Eff. Soil Oepth: > ISOca ■'- ••• ' a 7- .■ ca lOIR 2/2 (aoist) and 2.STR 2/2 Mixed, clay ♦ strong very fine subangular blocky structure. ... very hard (dry), sticky (wet), plastic (wit), coaaon very fine pores, strongly calcareous. . aany very fine and fine roots, field pH: 3.0, clear saooth boundary. ca IOTR 2/2 (aoist), clay, aoderate coarse edge shaped angular blocky structure, extreaely hard (dry), very sticky (wet), very plastic (uet), aany distinct intersecting slickensides on pedfaces, coaaon very fine pores, strongly calcareous, coaaon very fine and fine roots, field pH: 1.1, clear saooth boundary. .• . Bk ; 63: -( 110 c :a. IOVR 2/2 (aoist) and IOYR 2/3 Mixed, clay, aoderate aediua and coarse wedge shaped angular blocky ' \ <k 5i ■ ’*. ■ -r ••• ' .• .*I• 2 •»• ,• ‘:• .. *. • X ;■ ‘•■ t' ■ •. .■ • Bu 110110 ’.’?7rr . r, •<; - •*’•■• ' ■-•C • ■a 1»J ' structure, extreaely hard (dry), very sticky (uet), very plastic (uet), aany distinct intersecting slickensides’on pedfaces, cowon very fine pores, aany fine irregular 'soft calcareous white concretions, eitrerly calcareous, few very fine and fine roots, field pH: 9.0, dear saooth b.indary. ca 1011 2/2 (aoist), clay, aoderate aediua ad coarse wedge shaped angular blocky structure, very hard (dry), very sticky (uet), very :'astic (vet), aany distinct intersecting slickensides on pedfaces, fe» very fine pores, feu fine irregular ‘..soft calcareous white concretions, extrevly calcareous, feu very fine roots, field pH: 9.0. ’■ ■: . 2•- ■' -■ . • Print Date: 03/01/ •W-'<'? ' •v-L ■■ ■* i * . , ; V 1. t t*’. "■ ' ? •1 •* *' • • • i • ■t*’ V.-; ■> iiM 'R 'll hHOfILI:MG001 DIPTH PH IC p C I ClC03 Ce3O4 CIC Cl MJ I Total Act. II PBS I Hied . H20 I iS/ci ppi weight I ——• leq/lOOgr soil -—I A 0 20 8.0 0.0 0.1 0 3.38 0.28 0.0 10.1 ’7.3 71.8 42.5 4.5 1.7 1.6 58 0.0 B 20 43 8,1 0.0 0.1 0 1.52 0.43 0.0 5.2 (.0 70.0 63.0 5.2 0.5 6.5 100 0.0 C (3 110 0.4 0.0 0.8 0 1.19 0.09 0.0 24.6 \0 75.1 57.4 6.3 1.5 22.0 100 0.0 0 110 HO 5.2 0.0 1.1 0 O.lf 0.35 0.0 11.5 0.0 73.0 40.1 7.2 1.6 21.4 100 0.0 Particle she’(weight I) •• ' ? ■ / kS cS ■S\ fS. vfs cSi fSi Cliy ieq/100grl234567l5 CICcliy KI7I0DS A 0 0 3 0 0 0 32 65 0 B0 0 .V 2 0. 0 0 20 78 0 C 0 ?0 -10 0 0 15 84 0 D-0 J S l ,.o' ■• 0 0 17 82 0 Print due 03/07/52 I• a »la •J 5 ?S 0 IL I 11 • '' •’ ~a . r:. • PROFILE: BAGOOI ‘-r.'.'s • ; INFILTRATION (ci/hr) METHOD: SURFACE STRUCTURE STABILITY IMDEI: 1.00 : s ■ 1 DEPTH (c.f BULK OEMSITY (g/cc) VATER COMTEHT (night 1) 0.03bar O.OSbar 0.Ib.r O.Jb’r 1.Obar l.Obif S.Obar METHOD IS.Ibir ■ '*-• . «•< V A O' 20 • 1.21 ■ B 20-13 1.55 c 13 no 1.31 , o no no - 1.32 57.12 AS. 3 43.9 G5.35 62.2 57.0 77.12 60.0 47.2 73.62 56.3 52.4 42.1 42.3 44.0 39.5 Print date: 03/07/12 BAGO01 Available Moisture t' ■.■20cm ■ (Fc-pwp) X BD •5 63 cm 2.61cm (Fc-pwp) x X X BD ... • ilOOcm 15.36cm ,‘T (Fc-pwp) x X BD 16.05cm /•.Sv; y, vs ’■ ’/'A-V ‘v 35.02cm over 100cm depthI ."9 J i ■ = k -* *<■*” son HOfiiWhciiHioN Sheet/Grid: /1B50N S^OOE Location’/: 300 itferi'NE of Bench airk-11. Survey Area : Bale GadulI a Author(s) : Lucas Van Sleen Girua Asfav Helen Kuasa Classification FAO: Calcic Vertisol(1 SB!) Pellic Vertisol (IBM) - Rudic phase Profile: BAG002 Unit: 1-21 Status Coord : H 3 -02-00 E A0 -22-30 Elevation: 1811 ■ Date : 12/02/02 ST : Vdic Pellustert, cljy.y, aontaorriI oniiic(calc.),, Local Series : Asendabo Soil Series Soil dilate: vatic isotheraic Topography : gently undulating Eleient/Pos.! Alluvial Colluvial footslope- aiddle slope Flooding’ '1 rare Land Use’- : traditional grazing Vegetation t: seii-deciduous shrub Species*;* : Acacia Parent Material: colleviua over in situ weathered Rock Outcrops : nil • Surface Stones : aany stones Eroslonf'slight sheet erosion and slight deposition by water land Fori: valley Slope : 2 - Bl concave Micro Top: even Grasscover: 10-30% - derived froi basalt Sealing/Crusting: nil ■■ ■ .',S ' ■ •' .j. / Drainage^ L aoderately well, internal drainage: slow, extern?! drainage: rapid /’ Vatertablef not observed Moist.Cond: aoist 0 ■ 20 , dry 20 • 63 , aoist 53 - ISOci .>’ Huian;Infl: j..; Eff. Soil Depth: > ISOci • /• Reiarks:'Asendabo soil series,Calcareous pseudo-iyce1io In between 20-53ca feu and lany in between 63-108ca depth.Ci v/*ci wide at 50ca depth. Staples: A< 0-20 B: 20- 53 C: 53- 106 0: 100-155 E: 165-190 20 ci SYR 2/1 (aoist) and 10YR 2/1 Nixed, silly day, aoderate to strong fine and aediua subangular blocky structure, friable (adst), very sticky (wet), very plastic (wet), aany very fine pores, few aediua subrounded basalt rock fragaents, slightly calcareous, aany very fine and fine roots, field pH: 3.5, clear saooth boundary. SYR 2/1 (aoist) and 3.5YR 2/1.5 Mixed, silty clay, aoderate coarse subangular blocky structure, extreaely hard (dry), friable (aoist), very sticky (wet), very plastic (wet), few very fine pores, coaaon aediua subroundJ basalt rock fragaents, few fine irregular soft calcareous white soft segregation, aoderately calcareous, coaaon very fine and fine roots, field pH: 3,0, dear saooth boundary. 10YR 1.3/1 (aoist), day, aoderate coarse subangular blocky structure, extreaely hard (dry), friable (aoist), very sticky (vet), very plastic (wet), coaaon distinct intersecting slickensides on pedfaces, coaaon very fine pores, few aedjua subrounded basalt rock fragaents, aany fine irregular soft calcareous white soft segregation, extreaely calcareous, coaaon very fine 'nd fine roots, field pH: 3.6, . gradual wavy boundary. C '| T» wderate aediua and coarse wedge shaped angular blocky stricture, aaaannvy-pprrooaaiinneenntt iinntteerrsseeccttiinnog sslliicckkeennssiiddeess oonn opeeddffaacceess., ccooababoonh vveerryv ffiinn*e bpaoHh<e_s,f*fwew /’flne\subrounded' basalt rock fragaents, coaaon fine irregular soft calcareous white le 9' egation, extreaely calcareous, few very fine roots, field pH: J.I, , ‘ clear saooth boundary. ... . <u* Bur;q{'jB5?vi90 ci 3.5YR 2/1 (aoist), day, aoderate coarse wedge shaped angular blocky structure, friable (aoist), very sticky (wet), very plastic (wet), coaaon distinct partly intersecting slickensides on pedlaces, coaaon very fine pores, few calcareous white soft segregation, extreaely calcareous, nil roots, field pH: 7.8, 53MIJI XI» •'» i U I’t. I U 1 I » II f •PROFILE: BAG002 DEPTH PH EC PCN CaCOJ CaS06 CEC Ca Ng K Na PBS K find ' *;V Total Act. •* ’ 7, H2O I ■S/ci ppi weight l -1- •- nq/IOOgr soil -- -1 A 0 20 0.0 0.0 0.6 0 2.0$ 0.21 0.0 0.1 0.0 85.0 57.5 7.5 1.5 O.k 100 0.0 B • 20 13 B.2 0.0 0.1 0 1.19 0.57 0.0 JJ 0.0 69.6 50.5 7.0 2.5 0.5 100 0.0 C f S3 101 1.0 0.0 0.1 0 1.09 0.10 0.0 6.1 0.0 71.2 67.0 6.0 7.0 1.0 100 0.0 0 JOB IIS B.2 0.0 0.9 0 0.80 0.10 0.0 11.9 0.0 15.2 80.5 6.5 2.2 1.5 100 0.0 E IIS 190 1.6 0.0 0.5 0 0.80 0.03 0.0 13.2 0.0 63.1 50.5 6.5 1.0 2.0 100 0.0 Partic le liie freight 1) CECclay NETHOOS vcS cS i$ fS yfS cSi f Si Clay ieq/100gr1236567l9 B0 0 - D 0>.-0 .£ 0 .0 Print date; 03/07/92IM iJ M in E i/g4 *2 • . *4*z 9/ ,$ 0 ;I L'- U 1 S I C A L P R 0 » E I T I E S M0FILE!'BAG002 INFILTRATION (ci/hr) ••• METHOD: 1 2 3 1.9 27.8 '' 0.0 < .r • • .. S '£ .• SUMFA CE STRUCTURE STABILITY INDEI: 0.00 H VATER CONTENT (weight 1) 0.03bar O.OSbar O.lbar O.-bar METHOD I.Obar I.Obar S.Obar is.lbar • • > . 7i DERTH(c) 7 -■ BULK DENSITY (9/cc) 1' '^j 1 ’’ r iw | 1 ili •“ ll * M.: i• • Y ■- •i.* ’ ’ r? •■ i *; . ■ ■’’-V:- i.;- '• • A 0 20 1.21 .• y.z^-. ■ B 20. 63 1.22 C .63^108 1.25 D 101. 165 1.26 • Elis' 190 . .1.26 57.72 69.3 63.9 53.36 66.3 66.3 51 U 69.0 66.1 55.09 69.8 62.5 56.0? 6?.9 66.1 i| I If | LR ■ 1 62.1 37.5 37.3 31.1 37.7 Print date: 01/07/92 IJ • .Jj'.V '* i'r■j;. Available Moisture ■ ■ ■•■■ ■. £. . . . . . . . . . : ’• v 4ir. ‘r• ’’ -?! Q 0 C Hl :.j.(FC-pWp) x 20 X BD = 3.20cm $ 2'PO 63 cm: ■ ^&3Wi 0 ocm i ■? (Fc-pwp) x 43 X BD = 8.51cm .* :. . ( FC-pWp) x 37 X BD = 6.54cm ■ 18.25cm over 100cm depth •j*.. .*>4 -. •./ ’. i,v;-.r •r.'.SOIL FIOFILI DISCDIFTIOI'’• •7* iv» «,«• ... •? Sheet/Gridf /1J2O1;JI«1 Location,-: 550i,sw,of'Asendibo river or l.lki ll of BM-11. Survey Area : BileGidvlli Author(s); Lucas Van Sleen'-Glrui Aifav Melese toisa Profile: BAG003 Olit: T-23 Status: Coord : I 7 -07-10 I 10 -22-15 Ilevition: 1833 i Date : 12/02/92 •3 z J •*! ’* * < * % Classification FAoKvertliolslUII) Pelllc Vertisol ( 1974) - scdic phase '■ ST Yodic Pellustert, clayey, iontiorriloniticfcalc.),, Local Series : Asendabo Soil Series Soil dilate: ustic’iiotberilc Topography : ’flit > 'ileient/Pos,: terrace- ilddle slope Flooding ' ail???,' . Land Die : traditional grazing Vegetation :_ieil-deciduous shrub Species ' : Acscii*' land Fori: valley Slope : 0.7 - 21 straight Micro Top: even Gruscover: >701 •; ■'** ■ • U? ’ Parent Materiulijlniil deposits over in situ leathered lock outcrops MllS* Surface Stones : few stones ■1roslon:. slight' sheet erosion e • dei hid frot built ■ ' rDrilnige-iliioderitely.vell, Internal drainage: very slov, external drainage: slow intertable: not. observed ’ ' ;xolst Condifiolst^H , dry 15 • 200ci HuiaD.Infl:.</’".y leiarks:?Aaendabo soil-series.Cricki at 50ci depth. Siiples: A: ,0- 15 B: 15-73 C: 73-117 D: 117-210 v*i ?-> '- SeallDg/Crustiag: nil Iff. Soil Depth: > 150ci ■ 0 "A* C ,;*£ .J?. : ' s*< • 1 ’ - ' ’.?? c'. -iT.;; ... 15 ci? ioil 2/1 lioist), silty day, strong fine subangulir blocky structure, very hard (dry), . ■*>;^’friable?|iolst), very sticky (wet), very plastic (net), lany very floe pcres, '-^'extreiely calcareous, lany very fine and fine roots, field pB: 8.2, gradual siooth boundary. "'..A; ■o?. ^V■-y^ci^lOyi^/VI10111)* «iltT clay, loderate coarie ledge tbaped angular blocky structure, ■x'; ?' extreiely kiri ^7). wj iticky (wet), very plas-ie (vet), iaoy distinct * :&?&A£’3$£iitirsectii4 slickensides on pedfaces, laiy very fine pores, extreiely calcareous, iaoy fi jSS1 *=•’ B’ ■' r&* iy^i'very/flne’.ind conon fine r. .oot . . .s., f. .i*. eld. p. . H. . :. 8.0, gr . . . . . . .ad - •u -al —- wavy b - - - -ou- -n-d-ar- y. - - - - - - - - - - - - - - - - - —- - tC/ < :^Bk- fe X S'? ' ■■ A7;; f r y< . ■ 1 *3 il7'ci;SipTI’2)2liolst), silty clay, loderate coarse wedge shaped angular blocky structure, < ^’.extreeixtelry beiearly bd (ardrdy) (d, very)r, ve y stricy sky:tic’(kvey:t(|w, veetr|, ve y prlasy ptilcas (wtice (t)w, leant), i y daoy d istinicsttinct . soft-calcareous white soft .segregation, extreiely calcareous, concn very fine roots, field pH;/8.0, clear Irregular boundary. Intersecting slickensides on pedfaces, conon very fine pores, iaoy aediui spherical t 1/117 • 210;.ci>.:ipil.2/l (loist), silty clay, strong coarse wedge :-baped angular blocky structure, ’xr -• ■ - J ■' er ■ <ni'; ,utreeely.bard.(dry), very sticky'.(vel), very plastic (vet), eany prominent .^^•cintenecUng slickensides,on pedfaces, fev very flue pores, conon lediui spherical tokt * 9 *9*tioss, »trongly calcareous, nil roots, field pH; 7.1, fiV ^5 .< V • N/W" Print Dite: 04/07/92 56I '1 ,4I 0 I LA IA1TIBS 1 B S 0 L T S »'■ *t> / - •'7 PIOPIL1: BAG003 DBPTB B20 I BC P C I f ppi night I IS/CI ClCOJ CSO4 CIC Ci Ng K II Total Act. —— ------ seq/lOOgr soil -—I A’ 0 15 1.0 0.0 0.1 0 2.40 0.06 0.0 6.6 0.0 70.6 65.0 10.2 1.7 0.3 100 0.0 I 15 .73 1.2 0.0 0.3 0 1.19 0.27 0.0 11.3 0.0 79.0 65.0 14.5 1.2 0.5 100 0.0 c 73 117 1.4 0.0 0.3 0 1.03 0.74 0.0 21.9 0.0 70.5 40.0 13.5 03 6.1 100 0.0 0 117 210 1.2 0.0 0.4 0 0.47 0.49 0.0 13.4 0.0 77.2 64.5 15.0 1.4 6.3 100 0.0 Particle size (weight 1) CBCcliy «TIODS tcS cjjiS ,fS jfs cSl (Si Clay ■eq/100grl2345S7IS A 0 B 0 Print date: 03/07/52 BOUIk •1 i i = n r» B B B B B B B J 1 J if k k l < t t **■ n u n t i o o o to IISOIL PROFILE* DESCRIPTION Sheet/firid:/Ilkoil SklOE Location : H5i;SV of Asendabo river or l.5ki HE of BH-11. Survey Area* : Bale fiadulla Author(s) : Lucas Van Sleen fiirui Asfaw Helcse Kuisa Profile: BA6006 Unit: T-3 Status; »j ' •’V- Coord : Elevation: Date N 1 -07-15 £ 60 -23-00 1 029 ■ 12/02/12 Classification FAOf Vertisols( 1988) ST : Udic Pellustert, Soil Cl.iiate: ustlc isotheriic Topography : flat Eleient/Pos.: terrace- liddie slope Pellic Vertisol (1970) clayey, iontiorrilonitic(calc.),, Flooding Land Use Vegetation Species I I I I rare traditional grazing : sseeiblld-deeccldiduuooeusssshhrurubb : Acacia -- ; '■* T*"-' * Parent Materialb.fluvial deposits over in situ weathered Rock Outcrops : nil.'z Surface Stones : very few stones Erosion: slight sheet erosion and slight deposition by water •’ .. ” ’ Local Series : Veieb 5oil Series Land Fori: valley Slope : 0.3 - O.H straight Micro Top: even firasscover: >70% - derived frow basalt 5ea 1ing/Crusting: nil Drainage -Yioderately well, internal drainage: very slow, external drainage: slow Vatertab.le: not observed Moist Cond: ioist 0 • 11 , dry 11 • 111, ioist 111 • 195cw Huian Infl: Reiarks: Heyib soil series.Cracks lei wide at 6Sci. Saiples: A: 0- 11 B: 1b 65 C: 65-117 D: 112-112 E: 182-195 Eft. Soil Depth: > ISOci i -' 12/ci • ’• > • . < • -• - ai : •••■ < •> -?• 10H 2/1 (ioist), clay, strong very fine subangdar blocky structure, friable (ioist), ; ,very sticky (wet), very plastic (wet), tany very fine pores, very few itdiui subrounded basalt rock fragments, eitretely calcareous, tany very fine and Jine roots, field pH: 8.2, clear siooth boundary. •'*v ABi’v' : ^1JZ*/V5Vc|’;;IOIB V1 (■olst), clay, loderate coarse wedge s'aped angular blocky structure, Vr>e,J * .fi.aa.lv /^rvl wnnw haf d (drill sticky (wet), very plastic (wet) Ix.ll wa»u (..■*} I3fty distlhCt ’^intesrsliecckteinnsgidselisckoennspieddefsacoensp, eadafnaycveesr.yiafninvevpeorvrefsin, eeiotroerieesly calcareous, conon and ^ne r^ots, PH: 1.0, diffuse boundary. 65 - II?; ci‘\I0U 2/1 (ioist), clay, strong*coarse wedge shaped angular blocky structur k . .... , .- - *-I •i; .» . • • » • ***< - . *• * - z k - -- •• I’• j-f' revtreielv hard (drvl. varv <H^bv /aaH -r ; extrtiely hard (dry), very sticky (wet), very plastic (wet), lannyinptrho'i.i-nent ^intersecting slickensides on pedfaces, lany very fine pores, eitreiely calcareous, few ‘^Tvery fine and fine roots, field pH: 8.0, gradual wavy boundary. ■b ’,l (ioist), clIa -’y-Ji, •••• strong ,iediut wedg• ■e- ■s**3« ?) hap■«,«* n ed ijamni vigvbuHlf ai alr'IVbl'Illot, cky structure - _t>»«. : ’W*^",'1 V m • «k 1 a I — • * • 4 L ________________ -1 ! .1 t _ k » veryI »Vsti»- ckMy (wet), very p»VlasI tTicpi(Owle'ttJWC ), lanIyJ,pBrdoliinent > .. S ^C’7^-n-s-'-^--e-5-o-n P-W^fMttJes• ,••■linymfsinjv-iierireagwunlavri,svoafit:vcvajlcvallrlleUous white <»treiely calcareous, few very fine roots, field pH; 8.0, r.^fclear’siooth" boundary •"ZcS?**. •; ’£■ •* ’* 19^ciVb.5p\2/2 (ioist)', day*, loderate aedivi subanydar blocky structure, friable (ioist), ’ ,rT plast’c C0M0'' J’st'Mt intersecting slickensides ‘^gWpedfices, fev'sery fine pores, eitrenel, calureoiis, nil roots, field pK: I.}, H z.’ Print 0at»: Ok/OJ/92 z I 1‘ / /?-■■ I 58 •>- f >’ . f’ . ■ ■ *r» J * * *PROFILE: BAG004 OEPTH EC lS/ci PCN ppi weight t ClCO3 ClSOI Total Act. ................. i........................ - etc Ci «9 < Ni w ............ leq/IOOgr soil -4 K Hied H20 X • A 0 •ii ,0.2 0.0 0.5 0 3.16 0.19 0.0 1.0 0.0 71.6 15.0 12.0 2.2 0.3 100 0.0 B .1? IS M 0.0 • 0.3 0 2.00 0.75 0.0 9.1 0.0 71.0 10.5 11.5 1.0 0.3 99 0.0 C IS 117 M o-o 0.1 0 1.31 0.07 0.0 7.1 0.0 71.0 15.0 15.0 1.0 0.7 toe 0.0 D in 112 1.2 0.0 0.1 0 0.91 0.00 0.0 7.1 0.0 71.0 01.0 13.5 0.0 0.0 07 0.0 •* E 112 195 0.2 0.0 0.2 0 0.17 o.os 0.0 10.9 9.0 70.2 61.5 13.5 0.9 0.0 100 0.0 Particle sin* (weight 1) CECcUt methoos • 'v'. • • t ' j. ■ .V- •V • i kS c5 (S fS »fS c5i f$i dir aeq/IOOgr 1234SI789 1 1 1Ji- K- 1 1di & 0 19 ... ■ *' '« .'V•? 11f4cy] $ Print date: 03/07/92■ * H n n n n n5 01 K P H.T S I'C A L PROPERTIES PROFILE: BA6004 •r INFILTRATION (cs/hr) METHOD: 1 2 £j‘ *I I’• 5.S 5.1 S* 5 o.o' ;’y . • , . •■■ SURFACE STRUCTURE.STABILITY INDEX: 0.00 OEPTH (ci) IHI DEMSITY WATER CONTENT ((eight t) METHOD (j/cc) . O.OJbir O.JSber O.lber R.Tbar I.Obar Mbar S.Obar IS.Obar ’J . Print date: OA/OJ/12 1 7jp m .■J? L.'J. tM**! 1 ■<b ^Ep ■ • y,A- •-..Ji' ■v. .r . r; i/-.,. • • v •< . ’ ;< ■ •.<• -‘Yr ' ■• ••■ - •. . ’■><.■. -?> W.A ’-Z:- ’A' v, ... • • *. .■-' *.•' •< 0. ■'*•.•• • ■'•■ I; • / ■. ■ •« • ■! - ■, ?K'-. .: v\ . . •• - • -.v ..U A lid . ?i> < < ■. < • / “;■ - E£ -<• .m li • fp ’i .•_• ■ .«<;• . • ••V. l"*- • > ’ k . A-7 ' <■■.£ \ w'V’ $ ■•• r-'h - > - ' ■’• r . ' A<-* .’■ r 21.’, ■ • ■ ■WVr,I s■ • . ......4 ...... . :■ :.vi ; SOn'Pit9FIl?D'=CtIPTI^ » » • “ A f A ♦ » Au 1.4* Status: . Sheet/Gridi /njSNj.SSUE- location : . Survey Area : Bale Gadulla ,j Authorsi) ! Lucas Van Sleen Girui Asfaw Kelese Xuasa Coord c .lent ion: IBB ■ Gate : 13/07/92 • • • n‘; -r/' Classification/FAO: .Vertisols( 1988) ST. i'Udic’Pellustert, fel’ic Vertisol ;i9’i) - Ljji: onase cia/ey, •5r.ticrr;’oniti:r:ai:.i.l .o:?l S : we eb ;:• ' :*rit oi i'dicate: uStic isotheriic ; Topography gently undulating ;ard fori ■' El-nent/Pos. interfluve- lower slope •icce Flooding : nii Micro T:: land Use Vegetation Species : traditional dryland fariing- crors: wheat i i ■ •S * i * . Parent Material:. In situ weathered over volcanic ash ' Rock Outcrops ; njl -/Surface Stones : my stones Drainage : lodecately well., interna! drainage: very slow, external dninace: slow Vatertakle/nU observed. Gra5scover: ■ derived frci basalt Erosion: nil ■ ///< Sealing/Crusting: nil ‘ !- < . Moist Condi icisi'O -;20 , dry 20 Musan Inf V: 'ploughing 57 , sio’st 5) i sotn: IrCca Reararks: C.-acks Tea tide at SOci depth and deeper. LO-.ii (aoist/, chd. strong fine anc sed ;; ••-'•ng,‘a- it jit’re. • ‘Ft friable.(ioht), v«rv s:ku (wet-, e’er*. Set . iw /ery Hr* sere-. -•» •••* BtdiUB subromded u-a’t *o:i f'-gxe't: screwed :s’:a-*o.?. ssa» *er» •' .field pH: 8.2, clear u y boundary. /« ' r . • • ■ IOVR 2/1 (•ok ./ car. st-ang ccar- 1 eitreieh hard (dry/ »ery -:i:ky •• inter sec tiR* ?> i:»e'i’.*e; r terse ♦ery fine roitr ‘‘e ; :h: ?.(•, t,;: U15* • • snao-d ar g J a* st‘u:tu r-‘ ch-ti: (»•:•-. >»•< instinct .4 4 tor y- e/’rexe'. e : u.- .IM l)i (toist JI • =' extrenely harj lord ^intersecting si I i • ’ r ! v very fine roots, tied pH: 9.2, grana; , sron: :uar-e wedge.-re a?guia» thci/ f'itth , u“t st; *•< i .wet), ve-r •j : ture, •: *et . mm aroB > ns zedfixe:. h . .Kii’ft'jfcarso'.r/-!:: r.r. iiiriiH'-.-. uv-sf. •”e pores. ::ir.r. y ne *. * I • * } - * ■ e -• w •, • • •- -. t >4 4.f• . V -I 61 ■ ■■■■■■ s v ■ ................... >■,1fa.'-’ch r-H II n hEKOi■ ■ n n fa'.'ll TROFIU DESCRIPTION Sheet/Grid: ;i? 100W S61OE location : ?5a i(V of pond or IO75» ESE cl DM-iL Survey Area : Bak Gadulh Author(s) : lucas Van Sleen Girua Asia* Melese Kuasa Classification FAO: Vertisols( 1988) Pellic Vertisol (19k) - sodir ST : iJdic Pellustert, clayey, aontaor r i I on i t i c (ca 1 c. Soil Cliaate: ustic isotheraic Topography *. aliost flat Ehoeit/Pos.: depression- lower slooe Flooding : rare land Use : traditional dryland faraing crops: wheat Vegetation : Soecies : 'jreit Material: ir situ weathered ever vokinic ash ljc» .V.roos : nil - Surface Scenes : w-. st; ^5 c os?cn: nil and slight deoosil’on bv water Coorj : » * /•?* r 2? Ek*aI ion: i?in • Dak : 13/02/92 phase , local Series : Veieb Soil Series land Fora: valley Slore : 0.? - 21 concave Micro Top; even ira-scover: e’i v-7 koi less*4 r Drainage : weter.stle: dok: 'ond: HbSnr lnfl: kvk.g. f’i-' kegc: =’cw :ff. : *»’’ aooe-’ateh well, internal drainage: /er.’ slow, external net observed loist 0 • IS , dry 15 ploughing ’*5. v.ist ’15 - l6Ci« ’-r —: -k « Reaaks: Veyib soil series,sodic phase.Cracks 2ci wide at SOca depth -d here* 15- kC C: 1? »k [: i’:-i52 S: 3 •Qv; ; • J,-- friaa’e r /•’» ”k«. -e:. v =--. • teci'ji -utr'urJed '-rt :> frsgser.t:. e fire roots, f ell :h: J, :-s -a1 ;. 4:§.- • : »?••’ •** . :• !•*• <i*f h • . 1- • 4 •: • iC :a n«F: 2/1 ’ir-r. •r •. ■ i■- ■ • : •t; ■ ‘■ecg- s’ • ■ • i ?• g Jr 11 :• * ••• -jr3 .dr.). i ?•/ <s « ir.’-’se:’’^: ?’i:tr • : sub-;,n:?i oner. •• : celk:--. kj v:-. e • , >e: . »e'i c . :. k : • • • * • * *4 :*■ as. •V« t . 1 • -. •r •••r.; •i:ld Dt*- • v , • J. 3 :s- • S’. b0 • ”5 ’Ok 2/’ koi st), c’a* , str n: :or?e ■eo:e shsc » mJ r M:ck. ••• .-••re. utreiel/ hard (, very sticn «e: • . Hr* e* ;,i: :• :r. nr* intersecting slicknsi ;es oaJfsce:. con:' .• * r,- ;y-j, • • e . »’r.e - jo’s, Hel; :M: ’ 2. :1h <S»« b’Uh" •:$ - ISO ca 10k (aisv iM v'tt : 2 Mi»el b.. to:?» • • • I * ? t •ed>- 7- •. •’.. r bk Hath :ioir:, <e; v stick. ne*‘. .*•» ckr wet . i? r. iV-r-Ktin; slic-e* >i ••• •• cedfac-s, r < i ns :: ver» i-* sutrojrsed basal’ tA ir-:aerits. coaicn aediyr ’rr-jjlr soft :al oncretkns, eikeael :alis-e:.;. *-i «e r • • r »' * - •* ’ \ 63•J nF?.OF:LE: BAGU6 EF7H pH •: f c "3CC3 Tr.al Act. CaSO! «’n j lU u A aS':? prii xeioht i . . . . . . . . i . . . . . . . . . . . . . » : i- 3 /• •? 0 ? C.l i* : i n * • ’ r ’• : c 9.0 • . 1 c.o r.’ ? ’ 12 0.9 u ? [• r r us * r 0.0 At 4I4 : ’ r i: : : !M »£f ••: • • • / • •J c.t ... r . - • • j - ... ■... o.< rarticle size (weight t| CECclay methcts vcS rS is fS vfS cSi fSi Clay aeVlOOcrlJ!^7093 ■ i i n ■ U u II k k k k k k k kSOIL PHYSICAL PROPERTIES PROFILE: BAGC06 IKnL7?A7i:r k) SV’FACt 5T?.’-™’?E STABILITY XL! DEPTH (cd) BULK DENSITY WATER CONTENT imgtt I) (g/cc) O.OIbar O.OSbar O.lbu 3.3bar ’..Char A 0 0 C.00II m IISOIL PROFILE DESCRIPTION Sheet,'Grid: ,".340:1 5540’ localise. . 120n NE tf 3M-13.. Survey Area : Bale Gadnila Author is} : Lucas Van Sleea Gtruj Asia* Nelese Fuosa Classification FAO: Ver.isoiJi'.?:-' tri’.:' .'eriisol ’-'A. 57 . Udi: Pei’.jsts::, .-’.aysy acncacrrilrri::: :a’.' Sell dnaie: ur.rc isctherii: Tccisracay : flat Element .’Pcs. larr-cs- lexer s’.:?e Flccding • rare Lard Use traditional gracing Vegetation : seii-decaducus shrub Species : Acacia Parent Material: fluvial deposits over in situ weathered Mock Outcrops : very few - Surface Slones : very few stones Srosion: slight sheet erosion Drainage . acderately veil, internal dreir-c- very slow, er.err.i*. wa-.ertible: net observed Moist Ccr.j: aoist 0 - Z- . dry 23 - 150. 2:1st 1:0 - 160ca Ens: In:? Snarks: Xeyib s:iZ series.:u:ks I.::: wide r.7Cri. •,'r.rt T-K St’t'lF: 'corn . !i ’ -d-r E H -IMO Elevat-in. 1521 i Det? : 13/01 .c'il Series Lar: ?crri •i'.'.-: -er:?'- Circe : ■ - :• Him Tic. ever, C-ras-crver; - drived frea basalt Seaiinc/Crustir.? r.u fir* >:Z ?er..: ' lr'-r 5-rcZes I- Z2 = : ZZ- " ? j • .Z :d ZZ7?. ZZ . 7.3;.:’.: :::e i: 1.. ' ‘ . ve.-v •::r?v ’we: :‘.as:.: we: Ht? ver’ : - era- :.*= •*: ::::•. f.a.d :E c.-. :Ze-: : :s !??? Z ’. 3 i=; . :.-y iterate wedge s’:-:-: etg.lar :Z:vy eztreitly hard dry . ve:y sticky we: . very :Z- intersect::: slier.?:-.de; :r. r=d;a:es i-:y ver. : • r- very few - : we: . isry fist.:. : : i.fiise ZZ-i :: }:• 1 . ; e:tre:?:y dry . s* .:k; we: . ver. ::ter-e:::r: sZ::'?:’.dii :: red:--?- rZeer -rrta *::c:d’r.. zid-.ita •• :::• z z j;:rj :;y: : 2:i . ; ; : ,< . :r ; - - - *e ::er-e wedge ::ie:Ze 3:.st . very wet*. very :Zis:.- ?L::ker.:-;de- : raliarecus white •::: •e: e:a. ::. ::Z vs: • f-.-e ; ,e ; :e:..r r:*3i:e“ .- k * : •I 1 n to i H I I I I Ifl 0 v. r. u o : £ ; : ■ i~ •: n : a ; : : •: J *1 h : • •» - r. • k V . tJ i :c :: L 2- . i 1*13 *£3 SI* S} £i =: Sil 'flOHilK 1ei:J23 ■: :q::JKl =zxs 04 G 04 ri 04i •. s rzs j ’ 0 341 0*0 K4 is*c G ro 0*0 14 391 051 •1 • • •KI ri ri 541 > (J 145 0*0 14! 3*0 K'O 564 0 ro 34 3*: 35 1 01 •x • • ec .4 -; — • • • . 'i 54! C4 44’ cfl 0 1*3 04 S*3 Cl 4 Z - :: i‘j . V •43 : ,: .41 J V k » •• r J - • ,• T • - * i - w •■» : i « • • * U V 14 -. j ~- --.- •ft :-ii ........ ....... .. | . . . . . . i :cc i=s cdtj z; s: •ft i. 34 •• -1 [nc; f*-4 j i>i Hl 1 Cm zj 333 hJS*3 Z035J II J d 3i Hi Sid Zu .;oe« -riuoci S 11 fl S 2 a S2S11VMY ’JOSn to to to to to to to to toSCIL PHYSICAL PROPERTIES :NFIL7?ATION (ca.'hrl 5.0 :M ; 3.9 SL'PFACE STP.CCTUFF STAB!L1TT INDEI; O.K’ H-TH2D: LEF7H leal BULK DENSITY HATH CONTENT (weight t| NETE9C (;/cc) 0.03bar O.OSbar O.lbar 0.3bar !.?bn 3.0br 5.0bn IS.Obar 0n 1.17 5?.53 •’ IM 12 ' 70 !.-£ n - ••■ u 150 •ft i • - .f’ i; • »V. 5 i *. •: :: .5? ___ BAG 007 Available moisture 0-23 cm = (Fc-pwp) x 23 x BD 23-70cm = (Fc-Pwp) x 47 x BD 70 - 100cm = (Fc-Pwp) x 30 x BD 4.18cm • 11.27cm 5.86cm 21.31cm over 100 cm depth lu 2X1 68Appendix II Hydraulic Conductivity and Infiltration RateIP i i 9 IV IB ■ ■ 0 a a a a 0 a 0 0 0 0 0Hydraulic Conduct ivil y. To determine the hydraulic Conducti v- * y, rme at- i 1 it' fests were performed in most of the distinguished soil units. Tie tes* were executed according to the inversed auger hole method as described in "Drainage pr inciple and ap| lic.ations Volume III, Surveys and Investigations". 1 he principle is similar' to th* auger hole method.with this difference that in 'he inversed auger hoi method the Rate of fall of the water level »n the hole is measure instead of the rise. Erosedurgg Test locations were situated near t pits. This gave the advantage that the 1oc the soil units and the textural sequence of were known. Three augerings were made n profile pits up to one meter depth. After filled with water and the profile described dona to reach a wet condition in the profit The water filling was done from a jerican s to disturb the wall of the he 1 e by a flow cl of the first fill drained away the actual auger hole were measured. In some profile during the first fill the wail of the augei •a wider and less deep augei hole. e representative soi tions and consequent1 the soils to be teste ar- the represen tativ ugering the holes wer The first filling w a a as under i rr i ga t i on. ■ caiefully inorder not water. A f t * r the water width and depth of the it '-as oi se» • e J that hole collapsed causing For measuring the rate of fall of the *ater level a float and a measuring tape installed an a standard were used. After installation of this equipment the hole wa-; filled for the second time. The rate of fall was measured af ter 0. jO sec . 15 se: . ? •? sec , 60 sec, 120 sec 180 sec, 7 6 0 sec, 360 sec ~ «d 56 0 sec. Result At the time of Survey work it was obse» ved that the Slacking clay soils and cavities in the surface and sub soils, which are visible during augering, were impossible to examine because of the water flowing away through the cracks and civities. The procedure used for- the execution of permeability V st can be limited or influenced by the presence of soil cracks, I >les created bv roots, worms or larger' animals and the presence oi thin sand lenses may give unreliable figures. The test results ^re presented in M/dav for auger holes upto one meter depth. The classification of the Hydraulic conductivity is based on the following description:- •jl «l» t|» Q. < —• Q. ipVery slow S 1 ow Moder ate 1 y slow Moderate Moderately rapid Rapid Very rapid f H . 03 m/day 0.1 • ? - 0.12 m/day 0 . » 2 - 0 . G9 in/da y 0 . /• 9 - 1.55 m/day 1 . r r - ? .05 m/day ? . '>5 - U . 58 m/day > /• . 58 m/da v Source:- Soil Conservation er vice, USDA Dec. 19^8 Results of Hydraulic Conductivity tests Soil Mapping Unit Near* Soi 1 Tests result M/day Classif’ na tion Rema r k B-2- 1 b-2-2 B -2-3 B-4 - 1 B-i*-2 B-/* -3 6-6-1 B-6-2 B-6-3 B-7-1 B-7-2 B-7-3 0.55 0.66 0.73 0.2 2 0.7** 0.28 0.55 0 . i* 0 0.30 Moderate H ii - - - Mod e r at"'v S1?w Moderax el. Si ?w Mod? ra t ? y Slew Due to crack and c1 av elegging 1 Mod er-at e Moderate•y Slow Moderate 1 v Siow I n f i 11 ration Measu erne nts The infilt ration ca pacity r- fers to the vertical entr / of water into the soil su rface, for t ese measure ments the d oube Ring in filtromete r has been used. In • ere the initial inta ke rate and the equilibri um of the basic in ta'e rate has becom e con stant after several hours are the two intere t figures. The rate of infiltration is measured by observing the fall of water within two concentric cylinders driven into t he" so i 1 surface. The use of a double ring with measurement confined to the inner ring, minimizes errors due to flow divergence in direction other than the vertical. To avoid unre'iable results, water of the same quality as will be used for* irri ration should preferably be used for six hours. It does not work /ery well on cracked clays as the water disappears too fast and i suits are too variable but they indicate important aspects of soi physical properties. Evaporation rates are usual 1* but if the infiltration rate is very lo dry it is necessary to correct for convenient to carry out the test close the complete description on the soil i too low to be significant, and the weathei is hot and vaporstion. I* is aftei i a sampled profile so that obtai ned. 71rr-Qcedur Near should be the soil plastic or your hand over the the representative soil pro installed 3-10 meters apart, to a depth of approximately soil to wa ter' al 1 inorder* to reduce turbidity, replicates before starting the Pi tee t a depth,of about 10 cm and record the water in the inner cylinder using a ru:er or a hook gauge, same for the replicates and repeat th • i 1 e the Drive the cylinders 10-15 centimeters, dissipate the force -pare .I time and the height measurement after pairs of cylinders in to P 1 ace of the every thing ready for Fill both cylinders to of the Do t he 15 min, 30 min, U 5 min, remainder of the test. 60 min, 90 min, and 12' min, and each hour for* the The infiltration rate can be meas'T’ed either* by measuring the distance of the water surface from the top of the cylinder before, and after* topping up or* by measuring ' ie amount of water (using a graduate cylinder) required for* topping upto a fixed hook gauge. The former* method is simpler when diff-rent diameter cylinders are used. The outer cylinder should be ke» 1 at approximately the same level as the inner one. It is important that it should ne the inner cylinder or the measured wat fall. The recordings should be enters hour ly rates calculated. The curves < should be plotted on graph paper* and th infiltrated also plotted as a checl different rate from the other? it sh« the averages. er be filled up higher than ’ level may rise instead of I on a form and “he average infiltrations v e r s u s t i in - cumulative amount cf water If one cylinder gives •Id be rejected and taking 72p 0 0 n n n-------------------------------------------------------------- ---------------------------------------------------- il Infiltration Measured' nt results i Soi 1 Mapp i ng Unit Near Soil pit Test result Cm/h Remar k ■ 1-2-1 B-2-2 B-2-3 3.9 27.9 • B-6 - 1 B-A-2 B-6 -3 B-5- 1 B-5- 2 B-5-3 B-6- 1 8-6-2 B-6-3 B-7-1 B-7-2 B-7 3 5.9 5.8 — 7.0 9.3 26.5 7.3 7.2 11.2 i G.0 5.8 ‘.1 Impossible to insert the ring due to b u r r i e d s tones. Due to crack Due to crack 1 Due t •' •: i ack ------ ----------------------- . Jl For interpretation of th- obtaii made to FAO soils bulletin 62. In tbi figures are mentioned. If the i n f i 1 t r =s t i c n i r =. excess of 12.5 cm/hr, giavitv irriaat* because of difficulties with water percolation losses. With rate in the order of r d d a , i • -=■ t •= »• t n c e s “.a r» " - Publication, the follo^uig 1 1 i < h ' • 11 - » - rn i r- x ♦ n »• may no1 I • - pi 3.; ♦ . • 5 t r i b u t i «?r and excessive •-»• 1 ■= . surface waste of water* may be excessik up t i ma 1 0.7cm/hr and infiltration rates are 3.5cm/hr •gn i r.ude < f o . i con? i dere<j fQ looking to the figures of the re? same funny results are also obtained du in the subsoi1s. : lt> they show 7 to the cracks and 0 . ?cm/h. be tween 11.2 and c a v i t i -■ s 73Appendix III Laboratory Procedures! I * ■ I -• I I I i>• Description Method Rrocedire Texture Bydroieter Weight 50 g soi , if the soil la sandy Transfer to the llipeuation cop and fill 2/3 with weltbt 10 0 g. water. Add 10 i3 calgon solitlon stir for 30 ilnutes pour in’ <i the sediiutation cylinder ud take up to 1 da with liter. Beep the lediientatlon 1 cylinder li a c ustant teiperatsre bath at 20 C, if this is not vailable keep the cyliider on the work bench. Xi the suspension very well. Xote the tile is soc is the cyliider is kept it rut. Take tke teipei tire ud the hydroieter reading at the end of (0 e 1 tin and 2 honri. PI viter Ratio 1:2.5 Potentioieter Weight io gi o! soil suple ud add 25 il of distilled site: Shake for 30 linntes using electricil she' r and let it for overnight. Using pH leter enure the fl. pH Potassini Chloride Fotentioieter Weight 10 gi o soil suple ud add 25 il of 0.01 NIC! solu on shake for 15 ilnutes and take Ration 1:2.5 the pH reading Organic Ciboo I Malkely and Black chroiic Take soil sup i pass it through 9.2 u sine acid oxidation weight 1 gi or ess « transfer to conical flask Add 10 si of p .assiua dichroiate solution and swirl gently I ? flask to six the reigent with the Celciui Carbonate Bermrd' s Calciseter ^•llectrlcar-'' Conductlaetry -^Conductivity ■^'f’yi'twition ’ Ixtrict. soil. Add 20 and allow it t 200 il of dist 10 il of phosp pippet add twe indicator salt . with Xohr'aali titration the Place 0.1 gi i stall test tui flask pour thi 0.1 gi of call Take 50 gi of saturation ti. spatula take i 1 of cone. B2S04. Swirl the flask stand for about 30 ninutes, add lied water to each flask, place nric acid. Cool it using ostwald n three dropa of diphenyl nine ion. (Titrate the excess dichroiate solution) carry out the Blank lie way. soil in i conical flask using 5 add 101 diluted BCl io to ccnical del froi the inter. Do, triple Ji carbonate as standard oil ud uing distilled water lite the soil shoe falling freely froi e 1C readingI «<Iichingeable catlooi Sodlui Calcine ( Magnesias Anonius Acetate setbod Ilase photoseter Titration Take 10 gi of soil and leacb the soilby Meutral Anonios Acetate t 11 the total volose 250 el Standardized the f ne photoseter using pctassiui standards aad ran i» extract. Take 25 le the ex' by 0.01 ■ KOTA cot Kt and titrate the extract lex CIC Cilciui Chloride Take 10 gi of sol' 2H20 let it for o the solution cose‘ and equilibrate v calciu ion with l and saturated vitb 1 S CaC12< r night and leach the soil till (50-500 si discard the solution i 0.1 M CaC12, 2B20 replace the h Potassiu nitrate and collect in 500 voluietric lash. Titrate the exess chloride 4 using ISCM or Xei calcine ion. ric nitrate and titrate then 0 in In b b
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