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Not AvailableThe land resource inventory of Bisarahalli-1 microwatershed was conducted using village cadastral maps and IRS satellite imagery on 1:7920 scale. The false colour composites of IRS imagery were interpreted for physiography and these physiographic delineations were used as base for mapping soils. The soils were studied in several transects and a soil map was prepared with phases of soil series as mapping units. Random checks were made all over the area outside the transects to confirm and validate the soil map unit boundries. The soil map shows the geographic distribution and extent, characterstics, classification and use potentials of the soils in the microwartershed. The present study covers an area of 571 ha in Koppal taluk and district, Karnataka. The climate is semiarid and categorized as drought prone with an average annual rainfall of 662 mm, of which about 424 mm is received during south –west monsoon, 161 mm during north-east and the remaining 105 mm during the rest of the year. An area of about 97 per cent is covered by soils, three per cent by waterbodies, settlements and others. The salient findings from the land resource inventory are summarized briefly below. The soils belong to 14 soil series and 21soil phases (management units) and 9 land use classes. The length of crop growing period is about <90 days and starts from 2nd week of August to 2nd week of November From the master soil map, several interpretative and thematic maps like land capability, soil depth, surface soil texture, soil gravelliness, available water capacity, soil slope and soil erosion were generated. Soil fertility status maps for macro and micronutrients were generated based on the surface soil samples collected at every 250 m grid interval. Land suitability for growing major agricultural and horticultural crops were assessed and maps showing the degree of suitability along with constraints were generated. About 97 per cent area is suitable for agriculture and 3% is not suitable for agriculture. About 40 per cent of the soils are moderately shallow (50-75 cm) to shallow (25-50 cm) and about 57 per cent are moderately deep to very deep soils. About 24 per cent of the area has loamy soils at the surface and 73 per cent of the area has clayey soils. About 30 per cent of the area has non-gravelly soils, 60 per cent gravelly soils (15-35 % gravel) and 7 per cent very gravelly (35- 60% gravel) soils. About 17 per cent medium (101-150 mm/m), 67 per cent low (51-100 mm/m) to very low (<50mm/m) in available water capacity and 13 per cent area has very high (>200mm/m) available water capacity. About 84 per cent area has very gently sloping (1-3%) lands and 12 per cent area has nearly level (0-1%) lands. An area of about 85 per cent has soils that are slightly eroded (e1) and 12 per cent moderately eroded (e2). An area of about 41 per cent has soils that are moderately alkaline (pH 7.8 to 8.4), 26 per cent strongly alkaline (pH 8.4 to 9.0) and 8 per cent has very strongly alkaline (pH>9.0). A very small area of about 2 per cent is neutral (2%) in reaction. The Electrical Conductivity (EC) of the soils are dominantly <2 dsm-1indicating that the soils are non-saline. About 57 per cent of the soils are medium (0.5-0.75%) in organic carbon, low (0.75%) in organic carbon. An area of about 50 per cent low (<23 kg/ha), 45 per cent medium (23-57 kg/ha) in available phosphorus and one per cent of the area has high (>57 kg/ha) available phosphorus. About 54 per cent medium (145-337 kg/ha), low (<145 kg/ha) in 6 per cent and 37 per cent high (>337 kg/ha) in available potassium. Available sulphur is medium (10-20 ppm) in about 71 per cent area and about 26 per cent area is high (>10 ppm). Available boron is low (0.5 ppm) in about 79 per cent area and medium (0.5-1.0 ppm) in 18 per cent area. Available iron is deficient in about 47 per cent area and sufficient in 50 per cent area. Available zinc is deficient in about 76 per cent area and sufficient in 21 per cent area. Available manganese and copper are sufficient in all the soils. The land suitability for 27 major crops grown in the microwatershed were assessed and the areas that are highly suitable (S1) and moderately suitable (S2) are given below. It is however to be noted that a given soil may be suitable for various crops but what specific crop to be grown may be decided by the farmer looking to his capacity to invest on various inputs, marketing infrastructure, price and finally the demand and supply position. Land suitability for various crops in the microwatershed Crop Suitability Area in ha (%) Crop Suitability Area in ha (%) Highly suitable (S1) Moderately suitable (S2) Highly suitable (S1) Moderately suitable (S2) Sorghum 20 (3) 287 (50) Jackfruit 44 (8) 56 (10) Maize 17(3) 163(28) Jamun - 174(30) Cotton 3(<1) 373(65) Musambi 47 (8) 179(31) Redgram 17(3) 225(39) Lime 47 (8) 179(31) Bengal gram 3(