SOILS LAND SUITABILITY OF GADULA AREA 0^ ? *»- ”lL- / V ■*<’ 7'. ♦* *'E, * ’C J •; -.•.&/? v V l’W:i wRDA w ! ADDIS ABABA ✓'*’ ...SOIL AND LAND SUITABILITY OF THE BALE GADULLA AREA BALE REGION GIRUM ASFAW WRDA SOIL LABORATORY WATER RESOURCES DEVELOPMENT AUTHORITY ADDIS ABABASURVEY TEAM 1) ATO GIRUM ASFAW SOIL CHEMIST 2) ATO AMHA GETACHEW SENIOR SOIL TECH 3) ATO ALI MOHAMED SEBAN SENIOR SOIL TECH 4) ATO TEFERA AMARE DRIVERTABLE OF CONTENTS PAGE INTRODUCTION ............................................................................................................ 1 SUMMARY ...................................................................................................................... 2 ENVIROMENT ............................................................................................................... 3 3.1 Location, Communication, Population .......................... ..................................... 3 3.2 Climate ................................................................................................................. 3 3.2 A Temprature ..................................................................................................... 5 3.2 B Sunshine duration ........................................................................................... 5 3.2 C Wind ............................................................................................................... 5 3.2 D Rain fall .......................................................................................................... 5 3.3 Physiography and Geomorphology ..................................................................... ft 3.4 Water Quality for Irrigation ................................................................................. 6 3.5 Soils, Summerized ............................................................................................... 8 3.6 Land Use and vegetation ...................................................................................... 9 SOIL CHARACTERSTICS & LAND QUALITIES .................................................... 10 4.1 Soil chemical aspect ........................................................................................... 10 4.2 Salinity and Sodicity .......................................................................................... 11 4.3 Lime .................................................................................................................... 11 4.4 Organic Matter ................................................................................................... 11 4.5 Soil Fertility Aspect ........................................................................................... 11 4.6 Workability ......................................................................................................... 12 4.7 Rooting Space ................................................................................................... 12 4.8 Oxygen Availability ............................................................................................ 13 4.9 Erosional Hazard ................................................................................................ 13 4.10 Climatic Hazard .................................................................................................. 13 4.11 Flooding Hazard ................................................................................................. 13 LAND EVALUATION .................................................................................................. 14 5.1 Land Suitability Class ........................................................................................ 14 5.2 Suitability for Irrigated Agriculture ................................................................... 15 5.3 Recomended Crops ............................................................................ .............. 16 DISCRIPTION OF THE SOIL MAPPING UNITS ..................................................... 32 6.1 Soils of the Gently Dissecated Soil Complex ......................................... 32 6.2 Soils of the Alluvial Plain (Valley Bottom) ........................................... 36 6.3 Soils of the Steeply Dissecated soil Complex ........................................ 41TABLE OF CONTENTS LIST OF TABLES TABLE 1 Mean Monthly Evaporation and Temprature for PAGE Bale Gadula ........................................................................................................ 5 2 Guide Line for Interpretation of WaterQuality 7 3 Laboratory Determination of Weib River .................................. 7 4 Description of Lime in the Field 5 Footing Space, Temprature Preference of ................................................ 12 Some Crops 17 6 Irrigated Banana Land Suitability .................................... 18 7 Irrigated Beans Land Suitability .......................................................... 19 8 Irrigated Ground Nut land Suitability .................................................. 20 9 Irrigated Maize Land Suitability .......................................................... 21 10 Irrigated Onion Land Suitability .......................................................... 22 11 Irrigated Pepper Land Suitability ........................................ 23 12 Irrigated - Potato Land Suitability ................................................................. 24 13 Irrigated Sorghum Land Suitability ......................................... 25 14 Irrigated Tomatto Land Suitability ......................................... 26 15 Irrigated Wheat Land Suitability .................................................................. , . 27 16 Irrigated Sur Flower Land Suitability ................................................................ 28 17 Irrigated Barely Land Suitability ............................................................ 29 18 Irrigated Cotton Land Suitability ............................................................. 30 19 Irrigated Crops Over all Land Suitability ............................................... 31 20 Kinds and Number of Activities Completed ................................................. 48 21 Results of Hydraulic Conductivity ............................................................... 51 22 Minimum Temprature (°C) ............................................................................... 55 2-3 m Temprature (°C) ............................................................................... 55 2*4 Mean Temprature (°C) .......................................................................................... 55 2*5 Monthly Mean Sun Shine (Hours) 2‘6 Average Wnid Speed (m/s) at 2 meter 56 56TABLE OF CONTENTS PAGE APPENDIX - 1 INTRPRETATION OF ANALYTICAL DATA................................. 44 APPENDIX - 2 METHODOLOGY............................................................................... 47 2A-i Orientation ...................................................................................... 47 2A-ii Kind of Observation ....................................................................... 47 APPENDIX - 3 PHYSICAL MEASURMENTS ........................................................... 49 3A-i Hydraulic Conductivity ................................................................... 50 3A-ii Procedure ........................................................................................ 50 3A-iii Result ............................................................................................. 51 3B-i Infiltration Measurment ................................................................... 52 3B-ii Procedure ........................................................................................ 52 APPENDIX - 4 CLIMATICAL DATA ..................................... ........................... 55 & 56 APPENDIX - 5 SHORT LABORATORY PROCEDURES ................................. 58 & 59 REFERENCES ........................................................................................................ 60 ( i1. INTRODUCTION OBJECTIVE OF THE STUDY The Water Resources Development Authority in association with the Korean design team under took detail Soil Survey Investigation in Bale-Gadulla Valley for the benefit of a planned irrigation scheme. A soil survey of Bale Gadulla are resulting in the delination of land capability units for irrigation development on a level of detail. Under the agreed terms, the following additional information was to be provided for the project area. i) A soil map indicating the variations and distribution of different kinds of soils. ii) Laboratory analytical data and moisture characterstics of the important kinds of soils. iii) List of crops adopted to the climate and soils of the area. The terminology used for soil description and land suitability classification in this report is explained in the FAO (1976), FAO (1977), FAO (1979), FAO (1985) and FAO (1988).2 2. SUMMARY The report presents the findings of a detailed soil survey covering an area of 4500 hectars North-west part of Bale admini­ strative region. The objective of the soil survey was to identify the potential, with soils that are suitable for irrigation development. The whole findings are based on an array of field and Laboratory tests with over all field observation density of 1:6 hectars. Three main physiographic unit have been distingushed according to the nature of the slopes. 1. The Gently dissecated complexes (Kubsa platue) (straight slopes 1.5 - 3Z) with well drained, very deep clay soils, very strong calcareous. 2. An alluvial plan or valley bottom with slopes of 0.5 -1%, that has moderately well to imperfectly drained very deep soils of clay and silty clay texture. 3. The steeply dissecated complex (Erosional Convex slopes 2-5Z) that have shallow, deep gullies and stony which are affected, by flood and erosional Hazard soils of the gently dissecated complex and soils of the alluvial plain are deep, well structured and other physical and chemical properties are suitabile for irrigation development. Land suitability assessment and possible crops selection are included in this report with the assumption that sufficient irrigation water of good quality will be available and that the future farmers will master the anticipated required management skills.3 3. ENVIRONMENT •i 3.1 LOCATION COMMUNICATION POPULATION The survey area is part of the Welb river valley. It is located Four hundred fifteen (415 km) kilometer to the South-east of Addis Ababa, in North-western part of Bale Administrative region, tewenty three kilometer from Goro Awaraja. It comprises about 4500 hectars. The command area is situated within two districts or Awarajas, the upper platues of Kubsa Village is within Sinana Awaraga while the rest Villages namely, Solenamita, Alemkerem, Doreni and Gadulla are under Goro Awaraja. The boundary of the Survey area are bounded along the following feautures:- - To the North and to the east the area boundary concides with lower part of colluvial foot slopes of the mountain. - To the North-west the area bounded by Che contour line of 1940 and to the South by Weib river. - The approximate Geographical cordinates of the centre of the project area are 40°.16’ - 40°.37’ Northern latitude and 7°.6’ - 7°.9’ Eastern latitudes. According to the ministry of Agriculture, the peoples that cultivate the land in the survey area are members of the Oromo tribes. At the time of survey work the population density of the area was three thousand eight hundred eighty. Four elementary schools, five clinics serve for the association. Goro and Ginir the nearest townships are located about twenty-three kilometer west and east respectively. Accessibility to the project area is facilitated by dry weather ground road which connects Goro town with Ginir. Upto the dam axis the short grass vegetation and the relatively sparse cultivated fields makes off-road driving, easy.i LOCATION MAP LEGEND ia _ 16 n 1 ERITREA i . -I- I >—<’>-<• Infernofkxioi Boundary i Administrative -------------Region Boundary All Weather Road BALE “ K AtySA _k;_ NCH \ DAMO z 4 SOMA KENYA BALE I 3' Toxicity (Specific) Na+ (Sodium) (Adj SAR) Cl“ (Chloride) meqle B (Boron) mgle <3 <4 < 0.75 39 - 4 - io|j. 0.75 >9 > 10 >2 Miscellaneous effects NO3” (Nitrate) mgle HCO^- (bi-carbonate) meqle <5 < 1.5 ‘ik’i ;• 5-30 1.5 - 8.5 > 30 > 8.5 PH [ Normal range 6.5 - 8. 4 Result Laboratory determination of Weib river@ Table - 3 Lab determination Reporting Symbols Values Reporting Units Electrical Conductivity at 25°C PH Sodium Potassium Calcium Magnesium Chloride Ni trate Bicarbonate Boron Sulfate E cw pH Na+ K+ Ca++ Mg++ Cl- NO?” HCO3- B SO/.- 0.08 7.11 C.24 C.04 0.36 0.16 0.08 5.77 0.56 - (^/mho/ cm - Meqle* Meqle Meqle Meqle Meqle Mgle ** Meqle Mgle Meqle Mequle* - Milliequivalent per liter Mgle** - Milligram per liter @ - Water analysis carried out at water resources development water laboratory service.8 Conclusion The Weib river has low soluble salts, so no salinity problem, pH reading falls in the normal range. The toxic element, namely, Chloride, Sodium, and Boron are too small and cause no problem for irrigated crops. Generally from the laboratory determination Weib river has a good quality for irrigation. 3.5 SOILS. SUMMERIZED. Almost all soils are very clayey textured with a good structure and sufficent porosity upto 50 - 60 cm depth but a relatively poor structure and very unstable porosity below. Except the reddish brownish latosols the rest mapping unit have a strongly calcareous substratum containing abundant lime concreations and powdery lime. The top soils have 2 - 3Z Organic matter 1-2% for the sub soils with a high base saturation > 90%, Regarding of chemical fertility High cation exchange capacity, generally greater than 80.00 meg/100 gram of soil pH value between 7.00 - 9.00 due to the presence of lime concereations. No pronounced reading of salinity through out the project area, generally less than 1.00 milli mhos per centimeter. Their top soil tends to shatter in the form of fine blocky peds up on drying, which facillitates their tillage even in relatively dry conditions, as well as provides a natural mulce for the soil moisture. A few hydraulic conductivity /permeability/ tests and double ring infiltrometer tests were excuted near the representative pits. The infiltration tests results vary from 0.4 -3.1 cmipe.r hour. Under Natural condition of alternate wetting and drying, these soils form wide and deep cracks as well as get their I surface level disturbed due to the formation of small basins which creats additional management problems. Generally, the upper about 50 centimeter layer of almost all soils has relatively favourable physical and chemical characterstics for plant growth. ' *• * j i(9 The alluvial plain or Che valley bottom soils have developed that differ morphologically not much from those genetly dissecated complex soils. Some of the mapping units need minor comprovement i.e., clearing of surface stones from the field. Complete descreption of the soil mapping units are given in Appendix -1. 3.6 LAND USE AND VEGETATION The main activity of the local people is principally centered on farming and animal husbandary. Almost 50Z of the total area is uncultivated, covered by dense and scattered accasia and other short and tall trees. The large uncultivated are presently used for grazing. Rain fed agricalture is the; dominant kind of land use in the project area. . Farming practices are mainly traditional, 11»• .* • i P.. j ■ ■! ? • ploughing by ox. The main rainfed crops grown by !the local population t ”:.*H h are Maize, Barley, Wheat, Sorghum and d^ffrent spices. The farmers in the project area planted spices even more than the other crops /ear due to the afraid of different wild animals such as Swine, Pig Monkey etc. There are considerable live stock and polutary(numbe^ in the survey area, livestock is probably mostly fed with crop residue. Livestock consists of cattle and goats. More over* the producers cooperatives also have ailary farm with the help of Ministry of Agricalture near the project area. i1 I I, 10 - ! * i 4. SOIL CHARACTERSITICS AND LAND QUALITIES •, As mentioned earlier, a full description is given of the soil mapping units where all available information on each’ Unit is mentioned. This chapter summerizes that basic field information to the discussion on the limitations to irrigated agriculture and the determination of the suitability levels for the land use envisaged. The general aspect of the profile is a massive clay structured, sub-soil and the overlying topsoil well structured, friable, silty clay to clay soil, low lime concentration compairing with the deeper sub-soils. The defference between the well drained soils of the gently disscated and the moderately well to imperfectly* drained soils of the alluvial valley bottom is only gradual,iin the later some cracks and slicken sides are more strongly developed. i i'.l h • i Wl In general in the soil profile morphology of aljl, the deeper • rIi<1 l ' v If* soils no characteristics have been observed that are unfavourable to root development, such us abrupt textural changes, hard pans or stony layers. 4.1 SOIL CHEMICAL ASPECT The soils have high pH values for the top soils 7.00 - 8.50 and moderately high with increasing soil depth. For the valley bottom especially for the reddish brown latosols the pH value i falls between 6.00 — 7.00 due to the absence of lime concreation at any form. The above high pH reading for the most of soil unit is due to the lime content of the soil profile. In all soil types no (jjalinity problem encountered. Figures for electrical conductivity are less than < 1.00 millmhc.s per centimeter. '[ ,•%] i ** The soils have high cation exchange capacity (refers the capacity fo a soil to, sorb cations) compared to the clay content with a high Base saturation. Organic matter also moderate to high for the top soils and moderate to the upper and deeper subsoils. Calcium and magnesium are the dominant cations. All these figuers suggest quite fertile soils. No nutrient is found to be of extreme low value. But the excess of calcium and high pH reading could imply nutrient imbalance due to which some nutrients m^ight not be readily available to the crops.11 4.2 SALINITY AND SQDICITY Presence of salinity have been checked by means of Electrical Conductivity measurements: Electrical Conducti­ vity readings on the soil samples reveal salinity effects to be mostly negligible. Almost all electrical conducitivity readings are less than 1.00 mill! mhos per centimeter. Therefore, salinity does not seem to be of a problem, so the low salinity pose any harmful effects to most crops. levels In rare deep soils a relatively high sodium content percent­ age in the exchange complexes observed. This may contribute to an instability of the soil structure. 4.3 LIME Most of the soils of the survey area are moderately to strongly calcareous through out with an average lime content 5 - 20Z. The content of lime increases with increasing soil depth. The nature of lime found is in the form of powder or nodule concretion. In some cases the lime is undistingushable by the naked eyes, and 10Z diluted Hydro-chloric acid reaction ' ‘reveals the effervesence'of.the lime.* In some of 6oll types concretion of lime observed. Field description were used for detection of lime content is as follows. 4.4 ORGANIC MATTER Eventhough, by means of the soil colour it is usually very difficult to distinguish an organic matter accumulation (Horizon- A]) from the Laboratory data except the deeply dissecated soil complex the rest top soils centain 2 - 32 organic carbon. 4.5 SOIL FERTILITY ASPECTS Present level of nitrogen and phosphrous are low to moderate for all soil types. Exchangable potassium is adequate for growing any kind of crop. Present level of nitrogen, phosphorus and potassium are likely to reduce under future intensive irrigated cultivation .shortages may occur during double cropping situation over come by applying fertilizer application. If/ ’ I il. : »12 Table - 4 Field discription Auditory effect Useble effect Non-calcareous (less than 0.52) z None None ■•\ Very slighlty calcareous (0.5 - 1.0) faintly audible increasing to slightly Slightly faintly audible slightly more calcareous increasing to general, visible (1 - 57.) moderatly on close inspection Calcareous (5 - 102) easily audible moderate effect easily’visible bubble to 3 mm diameter Highly caleareous (102 <) easily audible general strong effect bubbles to 7 mm diameter easily visible 4.6 WORKABILITY Workability is a function of stoniness, soil texture and structure. It is considered for use of heavy machineries, minor land improvement such as removal of surface stones is assumed to be carried out whenever necessary. In the gently dissecated soil complex soil compaction and structure degradation is for seen when too frequent use will be made if heavy machinary. 4.7 ROOTING SPACE Rooting space is a function of effective rooting depth. In swelling and shrinking clays the rooting depth is slightly reduced. Rooting depth for the alluvial plain have no problem but limitation to agriculture due to restricted rooting space are found on the shallow of the erosional areas (steeply dis­ secated soil complex)•13 4.8 OXYGEN AVAILABILITY Oxygen availability is considered to be mainly a function of drainage class on all well and moderatly well drained soils no yield decrease is expected in view of restrictions to oxygen availability. 4.9 EROSION HAZARD Erosion hazard is a function of slope angle and infiltration rate. Water and wind erosion are the two types of active erosion in the area. Erosion hazard may be reduced by construction of bunds. The shallower soils are associated with the steepest slopes in the area. (§hese steepest slopes will not be used any way due to their rockey soil cover. Irrigation fields should be kept clear from these deeply dissicated;stream courses and gullies. 4.10 CLIMATING HAZARDS Climatic hazard is the function of the presence of hail and frost that affects crop growth. Hail is known to occer rarely in the survey area and the degree of damage to crops is not known yet. But no frost occu^red/observed at all with in or around the project area. 4.11 FLOODING HAZARD Flooding risk is the function of the destructive action of running water. In the dessicated soil complex land units flooding hazard is serious and good dist/ance should be selected from the flooding area. !. ’I- /1* .. * %: • • • *. i r<• Minor land improvement required to protect flooding hazard along small streams when ever necessary.14 5. LAND EVALUATION A full analysis of the farming systems with crops and crop rotations envisaged, is beyond the scope of this report. The evaluation of soil mapping units will be geared towards the following land use alternative medium scale farming improved technology under central management. The topographic and hydrological as well as the soils and climatic characterstics are integrated in the form of land characterstics and matched with the requirments of the land use to arrive at land suitability classes which are determined by the extent to which the requirements up the land use are satisfied and by the severity of limitations posed, if any to land use. The various land suitability class sympols used' for this report are defined as follows. 5.1 LAND SUITABILITY CLASS S^= Highly Suitable Land - Land class with the expected produ­ ctivity under a certain inputs level remaining above about 60% of that achieved from an idealy suitable land under the same i inputs level. ii Hl»' ' •» • ... I jf;! • T f. ’• S2= Moderately Suitable Land - Class with the expected productivity under a certain inputs level remaining between about 40 - 60% of that achieved from an iedaly suitable land under the same inputs level. S3= Land class with the expected productivity under a certain inputs level remaining below about 40% of that achieved from an idealy suitable land crop failures may be expected. N = Permenantly not suitable land - Land class which can not be economically improved for the envisaged used in any conceivable future time.r • '7 15 5.2 SUITABILITY FOR IRRIGATED AGRICULTURE The land characterstics are set againest the requirement of the crops. The temprature regimes for the two growing seasons are 17°C - ±9.8°C has been used for both seasons. These growing seasons include a dry period both at the beggining and end of each growing period to allow seed bed preparation respectively. Ripening and harvesting the two growing seasons cover the periods from Feburary till June and from August till December. D For each irrigated crop one table is presented. The major kinds of limitation affecting the productivity is indicated by the subclasses by class symbol. using lower case letter suffix with the e - Limitation w - limitation to to to to to erosional hazard workability r - Limitation inadiquate soil depth t - Limitation temprature regime i o - Limitation Oxygen availability. Assumptions The land suitability is assessed under the general assumptions i) lhe crops Co be grown wiould be.these* desciribed as climatically suitable. ii) The crops will be grown during the proper season i.e. according to the cropping calender described. iii) The availability and quality of irrigation water following ; will not be a limitation and the water will be applied through surface irrigation method, etc.16 5.3 RECOMMENDED CROPS Refering the irrigated crops over all land suitability (Table - 19) final rating of S| = Suitable S2 = Moderately suitable are recommended. Soil Mapping Unit Kll Total area - 160 ha moderately suitable for irrigation development i.e. moderately suitable for eleven of the irrigated crops. Soil Mapping Unit K22 Total area - 620.8 ha highly suitable for five of irrigated crops namely, beans, onion, potato, wheat, and barley and moderately suitable for six of the irrigated crops i.e., Ground nut, maize, pepper, sorghum, tomatto and sunflower. Soil Mapping Unit Al Total area - 1200 ha highly suitable for two irrigated crops and moderately suitable for nine irrigated crops. Soil Mapping A2 Total area - 2008 ha same suitability class with soil mapping Al. Soil Mapping A3 Total area - 478 ha highly suitable for five irrigated crops and moderately suitable for six irrigated crops. Soil Mapping EDl : — Total area — 341.6 ha not recommended for irrigated agriculture. Soil mapping ED2 Total area - 483.2 ha not recommended as arable land.17 Table - 5 Rooting space, Evapotranspiration Needs and Temprature Preference of Some Crops Crop Roating (cm) depth ET Crop mm Optimum mean Sensitivity to limitation in Ox. av. Banana Musa'spp. Beans Phaseolus vulgans 50 - 70 Ground Nut (Arachis hypogaea) 50 - 100 Maize (Zea Mays) Onion Allium cepa Pepper Capsicum annum 100 - 170 30 - 50 50 - 100 Potato Solanum tuberosum 40 - 60 Sorghum Sorhum bicolor 100 - 200 Tomatto Lycopersicon escu 70 - 150 Wheat Tt aestivum 100 - 150 Sun flower Lelianthus annus 50 - 100 Barley 50 - 100 i Cotton Gossypium hiresutum 100 - 170 250 - 500 300 - 600 400 - 750 350 - 600 600 - 900 350 - 625 300 - 650 300 - 600 450 - 650 - - 550 - 950 23 - 28 15 - 20 22 - 28 16 - 26 15 - 20 18 - 23 15 - 20 17 - 30 18 - 25 15 - 20 18 - 25 15 - 20 20 - 29 Moderatly tolerant Moderately senstive Sensetive Sensetive Moderately sensetive Moderately Sensetive Moderately if Moderately tolarant Moderately sensetive Moderately sensetive Moderately sensetive Moderately sensetive Moderately tolerant.18 Irrigated - Banana Land Suitability Mapping Unit KU K22 Al A2 A3 EDl ED 2 Temprature Oxygen Av. Rooting depth Workability Erosion Hazard S3 SI SI S2 SI S3 SI SL SI SI S3 SI SI SI SI S3 SI SI SI SI S3 SI SI .1 : si i t.■ ■ S3 SI S3 S3 jji S3 S3 Si N N N Ovgr. .all Land Suitability S3t S3t S3t S3t i 1 . •0 S3t S3re (N) N19 Table 7 Irrigated - Beans Land Suitability Mapping Unit Kll k 22 Al A2 a3 EDt ed2 Temprature Oxygen avail. Rooting depth Workability Erosion Hazard SI SI SI S2 SI SI SI SI SI SI SI SI SI SI SI SI S2 SI SI SI SI;,]; ’I Si'll siJfj si. J SI si 1 1 ll. si ft 4 h?3 S3 S3 SI SI N N N 1 Over all Land Suitability S2w • SI SI SI SI S3rwe (N) N20 Table 8 Irrigated - Ground Nut Land suitability Mapping Unit K 11 k 22 Al a2 A3 EDi ED 2 Temprature Oxygen av. Rooting depth Work ability Erosion Hazard S2 SI SI S2 SI S2 SI SI SI SI S2 SI SI SI SL S2 SI SI SI SI * 1 i i! • S2 || • i! Ji si L •j.’; 81 SI SI S2 SL S3 S3 S3 S2 SL N N N Overall - Land Suitability S2tw S2t S2t St2 S2t S3rwe (N) ■N21 Table - 9 Irrigated - Maize Land Suitability Mapping Unit *11 K 22 Al a2 a3 EDi ED 2 Temprature Oxygen Av. Rooting Depth workability Erosion Hazard S2 SI SI S2 SI S2 SI SI SI SI S2 SI SI SI SI S2 SI SI SI SI d s2 ■ i 1 si : «l J SI S2 SI S3 S3 S3 S2 SL N N N Overall Land Suitability S2tw S2t S2t S2t S2t S3rwe N /22 Table - 10 Irrigated - Onion Land Suitability Mapping Unit K 11 ' K22 A1 A2 a 3 ;» *■ I 1 edl ed2 Temprature Oxygen Av. Rooting Depth Workability Erosion Hazard SI SI SI S2 SI SI SI SI SI SI SI SI SI SI SI SI Si SI SI SI I* i •I sr i • i. si SI SI SI )f SI SI S3 S3 S3 SI SI N N N Overall Land Suitability S2w SI SI SI SI S3rwe (N) N • , *» s* I ». I .t i23 Table - ip Irrigated - Pepper Land Sutability Mapping Unit - *11 *22 Al a2 a3 edl ED 2 Temprature Oxygen Av. Rooting depth Workability Erosion Hazard S2 SI SI S2 SI S2 SL SI SI SI S2 SI SI SI SI S2 S2 SI SI SI S2 SI SI Si'. SI S2 SI S3 S3 S3 / S2 SI N N N Overall Land Suitability S2tw S2t S2t S2t S2t S3rwe (N) N ■ 'l I'l: '• ■J. !: I:- 7'- • I? . •1 >c 1* .2^i Table 12 f I Irrigated - Potato Land Suitability Mapping Unit K 11 K 22 A1 A2 A3 ED 1 ED 2 Temprature Oxygen Av. Rooting depth Workability Erosion Hazard SI SI SI S2 SI SI SI SI SI SI SI S2 SI SI SI SI S2 SI SI SI 1 <; •< :1 j SI !|S1 d SI SL SI SI S3 S3 S3 SI SI N N. N Overall Land Suitability S2w SI S20 S20 S10 S3rwe (N) N f I i i25 Table 13 Irrigated - Sorghum Land Suitability Mapping Unit K 11 K 22 A1 A2 A3 “l ED 2 Temprature Oxygen Av. Rooting depth Workability Erosion Hazard S2 SI SI S2 SI S2 SI SI SI SI S2 SI SI SI SI S2 SI SI SI SI S2 SI SI SI SI S2 SI S3 S3 S3 S2 SI N N N Overall Land Suitability S2tw S2t S2t S2t S2t S3rwt (N) NTable 14 Irrigated - Tomatto Land Suitability Mapping Unit K 1I K 22 A1 A2 A3 ED 1 ed2 Temprature Oxygen Av. Rooting depth Workability Erosion Hazard S2 SI SI S2 SI S2 SI SI SI SI S2 S2 SI SI SI S2 S2 SI SI SI ■ .h'i. • 1 • ' 1 s iir *!: SL' -• fe1’ sl l SI SI • S2 • SI S3 S3 S3 S2 SI N N N Overall Land Suitability S2tw S2t S2Ot S20t S2t S3rwe (N) N27 / Table 15 Irrigated - Wheat Land Suitability Mapping Unit Ku K 22 A1 A2 A3 ED 1 ED 2 Temprature Oxygen Av. Rooting depth Wrokability Erosion Hazard SI SI SI S2 SI SI SI SI SI SI SI S2 SI SI SI SI S2 SI SL SI ■i< ,'■> |'v ’si$ ' Hii s * • ■* SI SI SI SI S3 S3 S3 SI SI N N• N. Overall Land Suitability S2w SI S20 S20 SI S3rwe (N) N28 Table 16 Irrigated Sun flower Land Suitability Mapping Unit Kll *22 Al a2 a3 1 EDX ed2 Teirprature Oxygen Av. Rooting depth Workability Erosion Hazard S2 SI SI S2 SI S2 SI SI SI SI S2 S2 SI SI SI S2 S2 SL SI SI S2 SI SI SI SI S2 SL S3 S3 S3 S2 Ir" ;isi j ■ •»N N N Over all Land Suitability S2tw S2t S2ot S2ot S2t S2wre N29 Table 17 Irrigated - Barley Land Suitability Mapping Unit Kll k 22 Al a2 a3 k i! ’’• ill’’■1; ed2 Temprature Oxygen Av- Rooting depth Workability Erosion Hazard SI SI SL S2 SI SI SI SI SI SI SI S2 SI SI SI SI S2 SI SI SI SI SI SI SI SI )« jl - SI i SI S3 S3 S3 SI SI N N N Over all Land Suitability S2w SI S2o S2o SI S3rwe N30 Table 18 Irrigated - Cotton Land Suitability Mapping Unit KU k 22 A 1 . a2 a3 ED! ed2 Temprature Oxygen Av. Rooting depth Workability Erosion Hazard S3 SI SI S2 SI S3 SI SI SI SI S3 SI SI SI SI S3 SI SI SI SI S3 SI SI SI SI S3 . ? i' si 1 * 'H S3 J S3 S3 S3 SI N N N Over all Land suitability S3t S3t S3t S3c S3t S3twer (N) N31 Table 19 Irrigated Crops Over all Land Suitability Mapping Unit Crops Kll k 22 A1 a2 a3 EDj ED 2 Banana Beans S’ Ground nuts/ Maize x/ Onion/ Pepper Potato / Sorghum Tomatto Wheat 7 Sunflower J Barley 7 Cotton S3t S2w S2tw S2tw S2w S2tw S2w S2tw S2tw S2w S2tw S2w S3t S3t SI S2t S2t SI S2t SI S2t S2t SI S2t SI S3t S3t SI S2t S2t SI S2t S2o S2t S2ot S2o S2ot S2o S3t S3t SI S2t S2t Si S2t S2o S2t S2ot S2o S2ot S2o S3t S3t SI S2t S2t SI S2t SI S2t S2t SI S2t SI S3t N N N 17 Ni ' i* - N N N N N N N N N li N N N N N N N N N Explanation of Symbols t - Limitation due to Temprature o - Limitation in Oxygen availability r - Limitation in rooting depth w - Limitation in workability e - Limitation due to erosion hazardDESCRIPTION OF SOIL MAPPING UNITS 6.1 SOILS DEVELOPED ON GENTLY DISSECATED COMPLEX This soil complex embrace soils of the Kubsa Platue and soils of the transition to the alluvial (valley bottom) soils. Soils on the gently dissec^ted slopes can be generally characterized as well drained dark, friable strongly calcareous, slightly cracking clays weakly to well developed sticken sides, massive and compact sub and deeper sub soil. On the soil map a separate has been indicated between mapping unit and mapping unit K22 which in the down slope postion contains less of surface stones and moderately drained soils. •j SoiJ n.rq ping unit Surface area - - 160 ha No of observation - 13 Augering - 5 Profile pits and detail surface soil observation. Parent material - Basalt Topography - Colluvial slopes 1.5-3% Drainage Condition - Well drained Land use/ vegetation - Short grass, scattered accasia, thorn bush, and cultivated different cereals such as, maize, barely, wheat. Permeability Surface feature Brief soil Descri­ ption - Slow - 3 - 10 cm diameter of surface stone 5 - 15% 2 - Well drained very deep Black, 5Y , topsoil friable to firm sub and deeper sub soil, strongly calcareous, increase with depth, randamly, surface cracking, non saline, and no noduels, no rocks in the deeper sub soils, well distrubted roots on the top soil.Typical profiL Location Elevation Profile 0 - 20 cm 20 - 50 cm 50 - 100 cm 100 - 150 cm 33 characters tics - Observation site No. G[ near Bench mark 10 - 1936 mts - Black 5Y2/1 moist fine and medium granuler, sutangular blocky friable strongly calcareous, with diffuse boundary. Consistence, is soft to slightly hard when dry, friable when most steeky and plastic when wet, well distributed fine to medium roots, non saline Electrical Conductivity and pH (1:2.5 soil water suspension) 0.35 Mmho/cm and 7.70 respectively. - 5Y2/1 moist 10YR3/l dry, modrate, medium and coarse angular Blocky very sticky and plastic when wet, slightly hard to hard when dry, friable to firm when moist, weakly developed slicken sides dear boundary, common roots, strongly calcareous with pH value 8.10 and 0.18 Mmho/cm electrical con­ ductivity reading (1:2.5%, t-oil-water) . - Dark reddish brown (5YR /2) angular blocky-* massive structure few fine roots. Common white spots of lime, very strongly calcareous gradual boundary, consistence, hard when dry firm when moist very sticky and very plastic when wet 0.22 Mmho/cm and 8.4 pH value (1:2.5% soil/water ratio). - Dark reddish Brown moist, sub angular blocky, very few roots strongly calcareous sticky and plastic when wet, friable to firm when moist, gradual boundary, Ec value 0.24 Mmho/cm and pH value 8.7. 2Typical Profile Location Profile 0.20 cm 20 - 60 cm 34 - Characters tics - Observation site No G2 - Moist, fine sub angular blocky very strongly 22 calcareous, Black (5Y /1 - 5Y /2), with clear boundary many roots, consistence, is soft to slightly hard when dry friable when moist, sticky and plastic when wet, no rodules and rockes, some scattered lime powder non saline, Ec and pH values are 0.28 Mmho/cm and 8.2 respectively 1:2.5 water suspension). - Ccarse, angular Blocky, few fine roots, 4 well developed slickensides very strongly calcareous, consistence firm when moist hard to very hard when dry. Very sticky and plastic when wet, diffuse boundary, soft lime concreation dark reddish brown 15YK /2) few vertically cracking, with pH value 8.50 and 0.45 Mmho/cm Ec value. 2 60 - 100 cm - Dark reddish Brown (5YR*/2) massive, angular blocky few fine roots common lime concreation. Consistence, firin to very firm when moist very sticky and very plastic when wet, hard to very hard when dry. Well developed pressure faces. No noltting, no nodules, no rocks progressive boundary with 8.8 and 0.80 Mmho/cm pH and Ec readings respectively (1:2.5 soil-water suspension)35 Soil Mapping Unit K22 Surface area - 620.8 ha No. of observation - 12 Augering and .5- profile pits and detail surface soilr observation. Parent material Topography Drainage Land use, vege­ tation Permeability Surface features - Basalt - Colluvial slopes 1.5 - 3% - Moderate - well - Short grass, short thorn bush cultivated, ; different cereals. - Slow - Few, scattered, stones Typical profile characterstics Location Profile 0 - 30 cm 30 - 60 cm 60 - X10+ cm - Site observation G6, GIO, • - Moist coarse granular, friagle strongly i calcareous, many well distributed roots clay, hard when dry, friable to frim when moist sticky and plastic when wet, gradual boundary, pH - 8.3 an Ec - 0.3 Mmho/cm 2 2/2) dark reddish brown sticky and plastic, firm, hard, very fine common roots gradual boundary, pH = 8.5 Ec »« 0.41 Mmho/cm strongly calcareous. - Massive, moist 5YR /1 dark reddish brown strongly calcareous, crushed fine roots, well developed slickensides, consistence, hard when dry firm when moist very sticky and very plastic when wet water progressive boundary. - Moist, (5YR /1 - 236 6.2 THE ALLUVIAL PLAIN (VALLEY BOTTOM) SOIL COMPLEX These soils developed in the center and near the foot slopes of the mountain, covers almost half of the project area. , The general characters tics of the soil complex is flat (0.5 - 1Z) moderate to well drained soils, few cracks, silty clay to clay, a light texture compairing with gently dissciated soil complex. Non saline with some surface stones. Three mapping units are embraced within this soil complex^ Drainage condition and lime content are used for the separation of the soil complex. - Soil mapping unit A} - Dark reddish brown clay flat with few surface cracks, poor to moderately drained strongly calcareous. - Soil mapping unit A - Friable moderate to well drained light 2 texture, silty clay, silty clay loam, moderatly calcareous. - Soil mapping unit A3 - We?1 drained light texture, reddish brown, non calcareous with surface stones. /31 Soil Mapping Unit A^ Surface area - 1200 ha No. of observation - 30 Augering and 8 profile pits and detail surface soil observation. Parent material Topography - Alluvium. - Flat, 0.5 - 1.00Z. Drainage condition - Poorly to moderate. Land use/ vegetation Permeability Surface features - Cultivated different crops such as, maize, barley, different spices, short grass scattered accasia, thorn bush. - Slow to moderate. - Scattered few surface stones Typical Profile Characterstics Location Elvation Profile 0 - 20 cm - Observation site No. G-L7 , G-l8> G-39 Near bench mark 26 2 20 - 55 cm - - Moist, 5YR /1 medium and coarse subangular blocky many roots consistency freable to firm when moist slightly hard to hard when dry, strongly calcareous clear boundary Ec and pH readings are 0.14 Mmho/cm and 8.2 - Moist 5YR2/2 - 2/l dark reddish brown massive very sticky and very plastic when wet firm when moist and hard to very hard when dry, well developed stickensedes, very strongly calcareous, soft lime concretion s few fine roots, 8.5 pH and 0.38 Mmho/cm Ec ireasurment55 - 100 cm 2 10C - 160 cm 38 - Black, 5Y /1 compact coarse angular blocky few fine roots, well developed slickensides strongly calcareous, firm hard sticky and and plastic, no roduels, no rocks 8.9 pH and 0.28 Mmho/cm Ec value - 5YR /2 dark reddish brown, moist, no roots very strongly calcareous, common soft and hard lime concretions, progressive boundary, very sticky and very plastic, very firm, very hard well developed pressure faces, 2 8.7 and 1.67 Mmho/cm pH and Ec measurements respectively. •> . i .5 . V. - ’39 Soil Mapping Unit A£ Surface area No of observation Parent material Topography - 2008 ha - 38 Augering and 9 profile pits and detail surface soil observation - Alluvium - Flat 1.00 Drainage condition - Moderate to well Vegetation/ canduse Permeability Surface features - Uncultivated, covered byliishort thorn |‘;i •’? • bushes scatered accasia and different U trees. - Moderate - Few scattered surface stones Typical Profile Characterstics Location Profile 0 - 30 cm 30 - 60 cm 60 - 90 cm - Observation site No G-27, G-26, G-18 - 5YR2/2 moist medium subangular blocky friable, sticky and plastic, common roots moderatly calcareous, clear boundary, pH 8.6 and 0.13 Ec value - Coarse subangular blocky, firm when moist slightly hard to hard when dry, sticky and plastic when wet, common roots calcareous 5Y /1 Black, 8.9 pH and Ec = 0.68 Mmho/cm - 5Y /1 Black, diffuse boundary, few fine roots 2 2 some soft lime concretion,? sticky and firm, slightly hard, weakly developed sides no nouduels, no rocks, pH = 8.9 plastic sticken and t! % *; > l. Ec - 1.0 Mmho/cm ’.' Ja '.i j 90 - 150+ cm - Medium and coarse sub-angular blocky, massive few fine crushed roots, pressure faces between peds very few white spots, progressive boundary pH =• 8.7 and Ec = 0.99 Mmho/cm40 Soil Mapping Unit A3 Surface area No of observation - 478 ha - 13 Augering and 3 profile pits and detail surface observation. - Alluvium. 'I. • Parent material Topography j’.; » . * * - Flat. I Drainage condition Vegetation/ landuse Surface features Typical Profile Characters tics Location 0 - 20 cm 20 - 70 cm - Moderate to well drained. - Uncultivated area covered by short thorn bush and few cultivated area, mainly maize and different spcies, such as a bish. - Scattered surface stones. - Observation site No. G15, G19 and G25. - 5YR3/3 dark reddish brown, slightly moist, medium fine sub angular blocky, friable, many roots, silty clay, consistence, slightly sicky and slightly plastic when wet, friable when moist, loose to slightly hard when dry diffuse boundary. pH and Ec values are 7.20 and 0.12 Mmho/cm respectively - 5YR /3, dark reddish brown fine sub angular blockym weakly calcareous, moist silty loam, non slticky and not plastic firm when moist hard when dryclear boundary pH 7.5 and 0.17 Mmho/cm Ec reading. " b* 1 ii k* I ‘ii - Fine and medium sub angular, blocky very friable slightly moist,'5YR /3 dark reedish brown progressive boundary slightly sticky i *q C/K c'oy % 55 65 68 75 P (ppm) sill /day CEC (meq/IOOg soil) lexlure doss c C C C NH4 OAc-exTr. 75.0 68.0 62.6 67.8 KNOj - exlr. BULK DENSITY EXCHANGEABLE CATIONS (meq/IOOg soil) MOISTURE % W/V exch. Co o! pF 0 64.4 56.0 48.0 42.6 exch. Mg pF 1. 6.0 2.0 9.4 8.4 exch. K pF 2. 2.4 1.4 0.9 1.2 exch. No pF 2. 0.38 0.32 0 44 1 1 pF 2. Sum Cotions 73.18 59.72 58.74 53.3 • pF 3. % Bose Sot. (sum cat J pF 3. % Base &F (CECJ 97.6 87.8 93.8 78.6 pF 4.2 - ESP (sum-Cd. ) • < AWC (FIELD) ESP (CEC) J FC rep, 1 CEC (cloy froc.) 1 FC rep. 2 FC rep. 3 ' AWC (mm/m) AWC(Lob) SZ TUR A TION EXTRA C T pH -poste ECe (mS/cm) Soluble salts (meg/t) / AWC(corrected for coorse fragm) INFILTRATION (rote in cm. h-l) Utveroge~ij equation Sum cottons I I I I I I Co’* Mg" max. infiltration rote: COf" cveroge infiHrofion rote «___________________ HCOy- insfontonecus infillrolion rote offer 00-200 I I I OThER FIELD TEST DATA I■ G2 LABORATORY AND FIELD TEST DATA | LABORATORY N?. 0-35 35-80 80-120 PH-H2O(t v/v) 8.2 8.9 9.3 COARSE FRAG(%) - PH- CoC!? J TEXTURE EC (mS/in) | Coors e sond % 0.3 0.5 0.8 ■ medium sond °/o CoCOj (%) 11.0 19.0 29.0 fine sond % CaSO4 (7o) 1 tote! sond % 0C(%) 17 12 2.7 1.4 10 1.4 N(%) Q.3 0. 1 n.04 |% 1 doy % 20 24 77 C/N 63 64 68 P (ppm) | silt / day CEC (meq/!OOg soil) J texture c/oss C C C NH4 OAc-extr. 74.7 66.1 66.1 1 BULK DENSITY XNOj — extr. EXCHANGEABLE CATIONS (meq/iOOg soil) [ MOISTURE % W/V I Ot pF o exch. Co 54.0 44.2 42.6 exch. Mg $ pF 1. 8.2 7.2 8-2 exch. K ! pF 2. 1.6 Lfi 16 I? pF 2. exch. Na 1.1 8.2 10.8 Sum Cations ■. pF 2. 64.9 61.2 63.2 i • pF 3. % Bose Sot. (sum cot J I PF 3 7o Bsse S& (CEC) 36.9 92.6 95.6 | PF 4-2 ESP (sum- Cot. ) ,,5 i' J AWC (FIELD) ESP (CEC) j FC rep. 1 CEC (cloy froc.) a a a FC rep. 2 FC rep. 3 AWC (mm/m) AWC(Lob) SA TUR A TION EXTRA C T pH -paste ECe (mS/cm) Soluble softs (meg/t) AWC(corrected for coarse frcrgm) 5 a a INFILTRATION (role in cm. h-i) .Average ~ equotion max. infiltration rote- averoge infill rotion rote •____________________ instontonecus inf ill rot ion rote offer 4h ■ Re pH cote Accumulated intake (cm) after a I Co** Mg** Sum cations CO J- hoot a Sum cnicns Adj. SAR other Boron (ppm) HYDRAULIC CONDUCTIVITY (AUGER HOLE) a a K( cm.h-t) Depth of lest (cm) 0-/00 100-200 OTHER FIELD TEST DATA « ILABORATORY AND FIELD TEST DATA g| LABORATORY K9. PMn 30/70 70/1 or PH-H^OU- y/v> 3.2 _ " COARSE FRAG(%) PH- CoCI2 I TEXTURE EC (mS/tm) 3.31 0.22 0.21 | Coorse sand % •. medium sand % Co CO, (%) 14.7 16.9 16.7 CoSO, (%) fine sond % OC(%) ' 3.4 1.7 | total sond % 1.5 15 10 15 N (%) 3.14 0.03 0.0T 1 Si" % 15 10 8.0 C/N J Cloy % 70 80 85 P (ppm) | 5/7/ / day CEC (meq/ lOOg soil) J texture doss NH4 OAc-exfr. 1 BULK DENSITY c r r KN03 - extr. 1.75 1.88 73.2 K74 ao aj EXCHANGEABLE CATIONS (meq/tOOg sot!) 1 | MOISTURE % W/V exch. Co ■' o' PF 0 64.6 58 5ft • exch. Ng 1 pr 1. 8.4 3.8 3.0 exch. K pF 2 1.8 0.64 0.64 exch. No | pF Z. 0.32 0.41 0.51 J pF 2 Sum Cations • pF 3. °/o Bose So!. (sum cot.) a * pF 3. % Bose So- (CEC) • I " pF A 2 ESP (sum- Cot. ) AWC (FIELD) ESP (CEC) • FC rep, f CEC (ctoy froc.) • FC rep. 2 SATURATION EXTRACT . | | FC rep. J pH -paste J AWC (mm/m) ECe (mS/cm) AWC (Lob) Soluble soils (meg/t) Nd '1 | AW C(corrected for ■ coorse fragm) K* | Co** I Average ■■ ■ equotion 5 max. infiltration rote: ■ averoge inf it!rotion rote ■ | INFILTRATION (rote in cm. h-l) Mg** Sum cations CO,*- HCO± * insfonlonecus infiltration rote offer 4h • C7~ | Replicate Accumulated intake (cm) offer SO, *■ th 2h 3h ) 3.0 2.4 2.3 20. 22 22 N (%) n 7 0 13 n i 2a 22 22 C/N P (ppm) 1 I day % 50 52 55 sin / doy CEC (mcq/IOOg soil) texture doss C NH4 OAc- extr. 85 81 80 76 BULK DENSITY KNO3 - extr. EXCHANGEABLE CATIONS (meq/lOOg soil) w. I MOISTURE % W/V exch. Co ot pF O pF <• 72 63 64 60 I ex ch. Mg 8 9.8 7.0 6.0 exch. K pF 0.5 0.5 0.5 0.7 exch. No I pF * 1.3 5.8 3.2 0.7 Sum Cotions PE 2. 81.8 79.1 74.7 67.4 • pF 3. °/o Bose Sot. (sum cot J I I I I I I I I I I I I pF 3. _______ pF 4.2 AWC (FIELD) FC rep, 1 FC rep. 2 FC rep. J AWC (mm/m) AWC (Lob) AWC(corrected for coarse froqm) INFILTRATION (rote in cm. h-t) Artroqe equation max. infiltration rote: averoge infill rotion rote % Bose Sa: (CEC) 96.2 97.7 93 4 88.7 ESP (sum- Cat. ) ESP (CEC) CEC (doy frac.) SA TUR A T/ON EXTRA C T pH -pos te ECe (mS/cm) Soluble salts (meg/t) Nd / ✓| td Co** 1 Mg * Sum cotions CO.1' HCQ” instonfonecus inf ill rot ion rote offer 4h : Ct” Replicole Accumuloti th >d intake 2h (cm) offer 3h SO4*- 4h Sum anions 1 2 3 Ad J. SAR ! OTHER Boron (ppm) HYDRAULIC CONDUCTIVITY (AUGER HOLE) 4 K( cm. h-t) Depth of test (cm) 100-200 OTHER FIELD TEST DATAG19 laboratory and field test data a a LA BORA TORY N*. 0/15 15/70 70/140 PH-H20(! v/v) : 6.4 . h.8 7.3 COARSE FRAG(%) PH- CoCI2 TEXTURE EC (mS/cm) ).13 0.07 0.1 Coorse sond % medium sond % COCO, (%) ( ).39 0.48 0.39 Co SO. (°/o) fine sond % OC(%) 7 toto! sond °/o ’.16 1.2 0.9 20 25 23 N(°/o) 0.2 0.2 0-1 J/// % 45 40 C/N 6< a a 40 cto/ % 35 35 . P (ppm) i sill / cloy CEC (meq/!OOg soil) texture doss NH4 OAc'Cxrr. 45.2 41.7 38.3 BJLK DENSITY KN03 - er/r. EXCHANGEABLE CATIONS (meq/tOOg soil) A MOISTURE % W/V exch. Co of pF 0 29.2 28.6 34.4 exch. Ng pF 1. 11 7.4 7.6 exch. K 1.1 0.8 0.7 a a a a il a pF 2. exch. No pF 2. 0.3 0.3 0.3 Sum Cotions pF 2. 41.6 37.1 43.0 • pF 3. °/o Bose Sol. (sum cot J pF 3. % Bose Sat (CEC) 92.0 89.0 Llq.q . pF 4.2 ESP (sum- Cat. ) AWC (FIELD) ESP (CEC) FC rep. f CEC (c/oy frac.) FC rep. 2 SA TUR A TtON EXTRA C T FC rep. 3 pH-poste AWC (mm/m) ECe (mS/cm) AWC(Lab) AWC( corrected for course fruym) Soluble softs (meg/t) No* / K* Co’* C IN ILTRATION (rote in cm. h-l) Mg** a Sum cot ions I i i i i I Average ~ ■ equation max. infiltration rate' averooe inf ill ration rote • CO.*- hcq~ insfonfonecus infiltrofion role offer 4h • Cl' Replicate Accumulated intake (cm) after !h 2h 3h 4h SO.*- Sum anions 1 2 3 Ad J. SAP _____ OTHER Boron (ppm) 1 HYDRAULIC CONDUCTIVITY (AUGER HOLE) K( cm. h-l) Depth if test (cm) O-IOO 100-200 Rep. 1 2 3 4 *1 . 1 1 ■ !’i; » OTHER FIELD TEST DATA •1 I ■ ■ G20 LABORATORY AND FICLD TEST DATA LABORATORY N?. 0/20 20/65 65/121 PH-H20(F v/v ) 8.3 9.0 COARSE FRAG(%) PH- CoCI2 TEXTURE EC (mS/cm) Coorse sond % 03 . 6.8 05 10 medium sond % CoCOi (%) . 9.2 . 13.3 fine sond % CoSO„ (%) toto! sond % 20 OC(%) 2.3 1.9 1.6 15 10 N(%) n ? n ? n or sM % 15 18 20 C/N S M w doy % 65 67 7Q P (ppm) silt / day CEC (meq/lOOg soil) texture doss NH4 OAc- extr. ■ c C C 51.2 62.0 68.7 KNO^ — extr. BULK DENSITY rvrnir.Mr.rADi r rATirujc fr*»r,/ir)n mil) ' i n > MOISTURE % W/V exch. Co ■ ot pF o 48 35.2 39.8 exch. Mg pF 1. 8.0 5.4 4.4 exch. K pF 2. 0.8 0.8 n s exch. No ■I pF 2 0.52 10.00 16.0 Sum Cations pF 2. 57.5 51.2 60.7 • pF 3. % Bose Sot. (sum cot J H pF 3. % Bose Sa! (CEC) 100 82.8 .8.9 ^.3, pF 4.2 ESP (sum- Cot. ) AWC (FIELD) ESP (CEC) CEC (cloy froc.) ■ I FC rep, 1 FC rep. 2 SATURATION EXTRACT FC rep. 3 pH -poste AWC (mm/m) ECe (mS/cm) AWC (Lob) Lf I J ■1 g 1 n1 1 1 / A WC(corrected for coarse frogm) Soluble salts (meg/t) Nc* /r* CoJ* INFILTRATION (rote in cm. h-l) Average c_- equation max. in filtration rote; ' averoqe tniurruiton rote ■ Mg*> Sum cations CO.*’ HCO$~ insfontonecus infHtrot ion rote of ter 4h Ct " Replicate s°<* Ih 2h 3h 4h Sum onions 1 2 3 Adj. SAR OTHER Boron (ppm) i .* r HYDRAULIC CONDUCTIVITY (AUGER HOLE) K( cm.h-t) Depth ot C1-tOO led (cm) 100-200 F mt 1 1 i •--------------------------- Rep. f 2 3 I• U :>p'. Lr OTHER FIELD TEST DATA • • • • ----------------------------------------------------------------------------------------------- IAi>’i/44 INTERPRETATION OF SOIL ANALYTICAL DATA INTRODUCTION In the course of the detailed soil survey a total of one hundred twenty two samples were collected and analyzed at water resources deve­ lopment soil laboratory service, where the following determination were made. - Texture (Silt, Clay, Total sand) - pH (1:2.5 Soil-water Suspension) - Total Nitrogen - Organic Carbon - Av. Phosphrous - Electrical Conductivity - Calcium Carbonate - Cation exchange capacity - Individual Cations (Ca, Mg Na, K) - Bulk density from disturbed samples. The base saturation is determined later from the cation exchange capacity and from the sum of the individual caltions. SUMMARY Soil Reaction The soil reaction is indicated by the measurement of pH value. All soil mapping units except mapping unit A3 the value of pH is between 8-9 the high value of the pH is due to the presence of soft and hard free lime concreations in the soil profile. There may be risk of nutrient imbalance and reduced availability of phosphorus and micro nutrients. Organic Carbon Organic matter levels are moderate to high for the gently dissecated and for the alluvial (valley bottom) soil complexes. Total Nitrogen Total nitrogen are slow to moderate the optimum application rates can not be obtained from the laboratory data and need to be derived from field experiments.I I I Apl/45 Salinity The Laboratory data confirm that the soils of the survey area are all non-saline. Ibe highest recorded electrical condu- tivity of the suspension is less than 2 mill mho/cm. No yield reduction is anticipated due to the low value of Ec measurments. Line All mapping units are moderate to strongly calcareous except I I I the reddish brown soils of the mapping unit A3. Cation Exchange capacity & Indvidual Cations The content of exchangable bases bound on the clay fraction is moderate to high values. Calcium and magnesium are the dominant ion on the exchange complex. Exchangable sodium and potassium levels are enough for plant growth. The cation exchange capacity for the dissecated and for the I alluvial plain are high. All these fegures suggests that the soils are quite fertile. Base saturation is 90 - 100Z. I I I I I I I I I I I i46 i i * APPENDIX - 2 METHODOLOGYAP2/47 ORIENTATION AND DENSITY OF OBSERVATION During the actual survey work in the field no aerial photographs of adequate scale were available. A topo survey had been carried out resulting in 1:2000 scale 1 meter interval contour line map, with every 200 meters cross sections, that presently serves is a bese for all maps in this report. The cross section at interval of 200 meters were used as a starting points for soil traverses. Along these grid lines, profile pits augerings and detailed soil surface observation the cross section and initially chosen 400 mts apart in order to obtain an over all coverage of the area at a density of 1:6,000 hectars. In the large homogenious or transitional areas, were supplemented with augering upto a 1:1.5 hectar. Kinds of Observation Along the sections augering were performed to a depth of 1.5 m to 2 mts according to the nature of the soil. More over detail surface soil observation also carried out. Surface soil observation includes, texture by field method, lime content using 16% Hcl, color, munsel colour Recording of soils nature were as follows - Colour - munsel soil colour chart - Texture - Field method - Calcareous ness - 10% dilute Hcl. and other characterstics along with drainage condition, land use, surface * and land form features, were noted on _wRDA sojil profile description form. e d Field investigations ineach land type by exposing soil profiles through deep pits and augering on representative sites. Collection of soil samples for laboratory analysis and of water samples to assess its suitability for irrigation. Correlation of soil survey data with specific features of different land types, preparation of soil map done. Also analysis of climatic data and listing of the adopted crops according to their suitability made and integration of soils and climatic data and matching with the crop requirments for assessment of'land suitabi lity for the selected crops were made.A total of therty-nine profil pits and augering were excuted Table -20 Kind and number of activities completed No Activities Description 1 auger hole observation - selective observation - detailed surface observation 2 Soil profile pits degging and description 39 pits, Appx. 1.5 Dmts 123 samples collected for routine analysis 3 Infiltration tests for each soil type and along the canal 4 Hydraulic conductivity (Inversed auger hole method) for each soil mappint unitAPPENDIX- 3 PHYSICAL MEASUREMENTSHYDRAULIC CONDUCTIVITY INTRODUCTION ■ ” > Inorder to determine the Hydraulic Conductivity, permeability tests were performed in most of the distinguished soil units. The test were executed according to the inversed Auger hole method as described in "Drainage principle and applications Volume III, Surveys and Investigations". The principle is similar to the auger hole method with this dif^rence that in the inversed auger hole method the rate of fall of the water level in the hole is measured instead of the rise. PROCEDURES Almost all test locations were situated near the representative soil pits. This gave the advantage that the locations and consequently the soil units and the textural sequence of the soils to be tested were known. Two or three augerings for light textures were made near the representative profile pits up to one meter depth. After augering the holes were filled with water and the profile described. The first filling was done to reach a wet condition in the profile as under irrigation. The water filling was done from a jerican so carefully inorder not to disturb the wall of the hole by a flow of water. After the water of the first fill drained away the actual width and depth of the auger hole were measured. In some profiles it was observed that during the first fill the wall of the auger hole collapsed causing a wider and less deeper auger hole. For measuring the rate of fall of the water level a float and a A measuring tape installed on a standard’were used. After installation of this equipment the hole was filled for the second time.! The rate of fall was measured after 0 sec., 15 sec., 30 sec.,, 60 sec., 120 sec., 180 sec., 240 sec.,* 360 sec., and 540 sec. The reading interval was changed according to the nature oi; the textural *- sequences, meaning , _In highly permeable soils and shallow auger holes the measuring time was shortened. 1 iRESULT At the time of survey it was observed that the cracking clay soils and cavities in the sub-soils, which were visible during augering, were impossible to examine because of the water flowing away through the cracks and the cavities. A complete list of soil units test results and the calssification is given in the next page. The procedure used for the excution of permeability test can be limited or influnced by the presence of soil cracks , holes created by roots, worms or larger animals and the presence of thin sand lenses may give unreliable figuers The test results are presented in cm/hr for auger holes upto 50 cm depth and upto one' meter depth respectively. the classification of the Hydraulic Conductivity is based on the folliwing description Moderatly rapid 0.4 - 0.8 m/day Rapid 0.8 - 1.6 m/day Very Rapid 1.6 - 3.2 m/day Extermely Rapid 3.2 - 6.4 m/day Immeasurable Rapid above 6.4 m/day Source:- Soil conservation service, US Department of Agric. 1968. Results of Hydraulic Conductivity tests Table -21 Soil mapping Unit Near soi 1 Test results (m/day) Classification D 50 cm D 100 cm Kll G-l 0.07 0.06 Very slow KU G-2 0.05 0.04 Very slow KU G-3 0.08 0.07 Slow K22 G-6 0.10 0.08 Slow K22 G-10 0.09 0.07 Slow Al G-l 7 0.15 0.13 Moderate Al G-39 0.23 0.19 Moderate a2 G-26 0.60 0.49 Moderate rapid a2 G-l 8 0.77 0.70 Moderate rapid a3 G-15 0.98 0.78 Moderate rapid a3 G-19 0.80 0.65 Moderate rapiduiNFLTRATION MEASURMENTS INTRODUCTION The infiltration capacity refers to the Vertical ent^ry fo water in to the soil surface, for these measurments the double ring inriltro- ineter has been used. In here the initial intake rate (in the first hour) after and the equilibrum of the several hours are the two basic intake rate has become constant The rate of infiltration is measured by observing the fall of water within two concentric cylinders driven in to the soil surface. The use of a double ring with measurment confined to the inner ring, minimizes errors due to flow divergence in directions other than the vertical. To avoid unreleable results, water of the same quality as will be used for irrigation should preferably used for the test. The test should be run for atleast six hours. It does not work very well on cracked clays as the water disappears too fast and results are too variable but they indicate important aspects of soil physical properties. Evaporation rates are usually too low to be significant, but if fib the infiltration rate is very low and the wether is hot and dry it is necessary to correct for evaporation. It is often convenient to carry out the test close to a sampled profile so that complete on the soil is obtained. PROCEDURE Near the representative of soil to be tested the pairs of cylinders should be installed 3-10 meters apart. Drive the cylinders in to the soil to a depth of approximately 10 - 15 centimeter. Place plastic or your hand over the soil to dissipiate the force of the water inorder to reduce turbidity. Prepared everything ready for all replicates before st a r ting the test. Fill both cylinders to a depth of about 10 cm and record the time and the height of the water in the inner cylinder using ruler or hook gauge. Do the same for the replicates, repeat the measurment after, 15 minutes, 30 minutes 45 minutes 60 minutes, 90 minutes and 120 minutes and each hour for the remainder of the test.The infiltration rate can be measured either by measuring the distance of the water surface from the top of the cylinder before, and after topping up or by measuring the amount of water (using a graduated cylinder) required for topping upto a fixed hook gauge. The former method is simpler when diffrent diameter cylinders are used. The outer cylinder should be kept at approximatly the same level as the inner one. It is important that it should never be filled up higher than the inner cylinder or the measured water level may rise instead of fall. The recordings should be entered on a form and the average hourly rates calculated. The curves of infiltrations versus time should be plotted on graph paper and the cumulative amount of water infiltrated also plotted as a check. (there is ample time to do this in the field between measurements and it should be done at once so that errors can be rectified. If one cylinder gives a widely different rate from the others it should be rejected in taking the averages. After the test period the cylinders are removed and an excavation should be made through the center of the thrity centimeter cylinder site inorder to drow the outline of the wetted soil on graph paper. From the graph the values of the maximum initial infiltration rate can be calculated.54 1 - CLIMATICAL DATA APPENDIX 4 tAp4/55 Table - 23 Minimum Temprature (°C) Year Jan Feb Mar Apr May June Jul Aug Sep Oct Nov Dec 1980 1981 1982 1983 1984 1985 1986 1987 - 9.1 10.3 8.4 6.4 12.5 12.1 12.1 - 10.9 11.6 11.1 6.5 13.9 13.2 13.2 - 13.1 11.7 12.3 8.4 12.6 J4.1 14.2 - 13.6 13.2 13.3 12.3 9.4 13.2 14.5 13.3 12.5 12.4 13.1 10.6 9.1 12.9 13.3 12.5 11.6 11.9 12.1 - 12.8 13.6 13.1 13.0 11.4 12.5 12.5 12.5 12.7 14.1 13.7 12.5 11.9 11.8 13.1 12.1 12.0 14.5 13.9 11.7 11.5 11.2 11.8 12.3 8.9 13.3 13.7 11.9 11.3 11.1 11.2 12.7 8.1 13.3 13.0 10.1 8.7 6.8 9.3 13.6 12.1 12.7 14.8 8.0 7.9 9.9 - 8.4 - 12.3 15.8 Table - 24 Maximum Temprature (°C) Jan Feb Mar Apr May June Jul Aug Sep Oct Nov Dec 1980 1981 1982 1983 1984 1985 1986 1987 - 28.7 26.7 26.5 27.5 27.4 - 27.4 - 27.6 27.3 26.3 28.6 26.5 - 27.8 - 24.1 28.3 29.3 28.8 25.4 28.1 27.2 - 23.3 23.9 26.3 26.1 24.1 24.2 24.8 25.0 23.9 23.9 25.3 24.8 27.3 24.0 25.0 25.8 24.4 24.1 25.3 - 24.6 24.1 24.1 25.0 23.8 24.6 25.7 24.9 23.9 24.9 24.6 26.1 25.1 25.7 25.3 26.9 25.9 25.5 26.2 26.4 24.5 26.6 25.0 27.4 28.4 25.7 26,3 24.8 23.7 23.9 23.7 24.8 24.0 24.7 - 26.1 25.1 23.8 25.0 23.2 26.9 25.7 - 27.4 26.0 23.7 26.7 - Table - 2 5 Meai i Temp1 rature year Jan Feb Mar Apr May Jun July Aug Sep Oct Nov 1980 1981 1982 1983 1984 1985 1986 1987 - 18.9 19.5 17.5 17.0 20.0 - 19.8 - 19.3 19.5 18.7 17.6 20.2 - 20.5 - 18.6 20.0 20.8 18.6 19.0 21.1 20.7 - 18.9 18.6 19.8 19.2 16.8 18.7 19.7 19.2 18.2 18.2 19.2 17.7 16.6 18.5 19.2 19.2 18.0 18.0 18.7 - 18.7 18.9 18.9 19.0 17.6 18.1 19.1 18.7 18.3 19.5 19.2 19.3 18.5 18.8 19.2 19.5 19.0 20.0 20.1 19.1 18.0 18.9 18.4 19.9 18.7 19.5 20.0 18.4 ■7.5 17.5 17.5 18.8 16.1 19.0 - 18.1 16.9 15.3 17.2 18.4 19.6 18.2 - Dec 17.8 17.0 16.8 17.2 19.5 -Ap4/56 Table - 26 Monthly Mean Sun Shine (hours) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total 1980 - - - 8.6 7.9 8.1 8.7 6.3 6.5 8.9 10.8 65.8 1981 10.2 8.8 5.1 5.1 7.3 7.8 6.9 7.5 5.2 6.8 9.1 9.0 88.8 1982 8.0 8.0 9.3 5.3 6.6 7.8 7.1 6.9 6.5 4.6 6.2 7.0 83.0 1983 8.9 7.5 8.9 6.7 7.2 8.0 7.8 - - - 6.4 9.1 78.5 1984 10.3 10.3 - - 6.6 7.8 7.6 8.0 6.1 7.1 8.5 9.3 81.6 1985 8.9 7.3 7.0 7.5 5.7 5.5 6.5 - - 8,8 ..8-9 - 67.4 1986 - 2.3 8.1 4.0 6.7 6.0 7.0 7.5 5.5 ■/io; i: ’ ; 8. 5 9.1 71.7 1987 9.7 8.5 - - 5.3 5.9 - 8.5 7.2 5.1 - 50.2 Table - 27 Average Wind Speed (m/s) at 2 meter / Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total 1982 1.8 2.5 2.8 2.3 2.2 3.4 4.5 3.8 2.5 1 7 1.3 1.6 30.4 1983 1.9 2.3 2.6 2.6 2.6 2.8 4.1 3.7 2.4 1.5 1.3 1.4 29.2 1984 1.9 2.3 2.9 2.6 2.8 4.2 4.2 3.2 2.4 - 1.5 1.6 29.6 1985 1.6 2.0 2.6 2.3 2.1 - 3.4 3.0 3.7 1.9 1.8 1.9 25.3 1986 2.1 2.3 2.7 2.5 2.2 - - - 2.7 1.7 1.5 1.7 19.4 1987 1.9 2.4 2.7 2.2 2.0 2.6 3.8 4.2 2.7 1.7 1.7 1.8 29.7 1988 2.0 2.4 2.7 2.6 2.8 3.6 3.9 2.5 2.5 1.6 1.5 1.8 30.9 •i V I57 APPENDIX - SHORT LABORATORY PROCEDURES 5Ap5/58 DESCRIPTION METHOD Texture Hydrometer PROCEDURE Place 50 gm soil sample to the dispension cup and fill 2/3 with water and stir for for 15 minutes. .he •.’> • ‘ i. • * pour into the sedimentation cylinder and 3 make upto 1dm with water. Mix the suspension very well. NoteThe time as soon as the cylinder is kept at rest. Take the temprature and the hydrometer reading at the end of 40 sec, 4 min, and 2 hours. pH Water Ratio W/V (1:2.5) Potentiometric Place 10 grams of soil sample in 100 ml beaker and add 25 ml of distilled water. Shake for 30 minutes and let it over night. Ec Water Ratio Conductime- Using pH meter and EC meter take the reading. w/v (1^53___________ txi£_______________________________________________________________________ L Calcium and EDTA - Titra- Take 25 ml of leachate in 100 ml beaker and Magnesium Sodium and Potassium Organic Carbon tion Flame Photo­ meter Weakely and Black Chromic acid oxidation add calcine indicators titrate with EDTA. Prepare the corresponding standards and standardise the instrument and read the values Weigh 1 gm or less than pass through 0.'3 mm sieve and add 10 ml potassimu dichromate solution and swire gently the flask to mix the reagent with the soil. Add 20 ml of x Cone. H2SO4. Swirl the flask and allow it to stand for about 30 minutes, add 200 ml of distilled water and place 10 ml of phophoric acid. Cool it. Using ostwalled pipet add two drops of dyphenyl amine indicator solution. Titrate the excess eichromate with mohr's salt. Carry out the blank the same way with out the soil sample.AP5/59 DESCRIPTION METHOD PROCEDURE Calcium Carbonate i Bernard’s Calcimeter Exchangable base and cation excha­ nge capacity Sodimu Acetate (Titration and flame photo­ meter) (Flame Photo­ meter) Bulk density from Distu­ rbed samples Paraffin Wax Method Place 1 gm of soil in a conical flask and place 50% Hydrochloric acid in small test tube. Connect to the calcimeter. Pour the HC1 to the soil. Note the displaced volume. Do duplicate 0.1 gm of calcium carbonate as standard. Take 10 gms of soil and leach the soil by Sodium acetate solution till the total volume reaches 200 ml, keep this leachates for determination of individual cations. Transfer to another 250 ml flask, wash the excess sodimu by 95% ethanol solution and leach with Ammonium acetate, till the total volume comes 250. Weigh two clods and immerse into the paraffin was cover the whole. Surface as much as possible cool it. Weight again, place them in the graduate cylinder known volume and note the displaced volume. Calculate the bulk density.Doorenbos, 1979 Doorenbos, 1984 FAO 6G REFERENCES J, and A,K kassam: Yield response to water FAO, Irrigation and drainage paper No. 33 FAO, Rome J, and W.O Pruitt: Crop water requirements, FAO irrigation and drainage paper No. 24 FAO, Rome Irrigation practise and Water Management, FAO, Irrigation 1981 and drainage paper No. 1 FAO, Rome FAO Guide lines; Land evalluation for Irrigated agriculture, 1985 Soils bulletin No. 55 FAO Rome FAO Soil Survey Investigations for Irrigation Soils Bulletin 1979 No. 42 FAO, Rome FAO Water quality for agriculture Irrigation and Drainage 1985 Paper No. 29, FAO, Rome FAG A frame work for land evaluation soils bulletin 1976 No. 32, FAO, Rome 1985 NWRC, Guidelines for Soil Profile description. Skills transfer and Training Hand book No. 1 WRDA, ADDIS ABABA «• e ■ J