Soil fertility mapping of the district, grid based 546 soil samples were taken from 91 selected villages (13 % of total 911villages) covering entire district using Simple Random Sampling without Replacement (SRSWOR). From each selected village, six farmers {(two of each category) viz. large (>3ha), medium (1-3 ha), and small (<1ha)} were selected for sampling. Among the different methods of spatial interpolation of soil properties, kriging method was followed which is an optimal interpolation method. Kriging is a widely used method of geo-statistical interpolation that assumes no regional trend exists in the data.

The soil pH ranged from 5.4 – 7.6 and 80 percent of the soil samples were categorized under slightly acidic to neutral range which is suitable for all major crops of the district. Among the different soil parameters tested under study which recorded for fertility mapping of the district. Based on the total soil samples analyzed in the range and mean values shown in parenthesis for organic C as 0.21- 0.76 (0.50 %), available N as 100 - 376 (260 kg ha^-1), available P as 3.9 - 35.0 (15.9kg ha^-1), available K as 112 - 482 kg ha^-1 (314 kg ha^-1), available Ca status as 1032 to 6384 (3893 kg ha^-1), available Mg as 269- 2882(1261 kg ha^-1), available S as 7.56–92.12 (33.96kg ha^-1), DTPA extractable Zn content as 0.04 -1.68 (0.75mgkg^-1), DTPA extractable Fe content as 3.30 to 57.54 (26.05 mg kg^-1), DTPA extractable Cu as 0.20 -10.32 (1.81 mg kg^-1), DTPA extractable Mn as 0.68 - 61.66 (30.15 mg kg^-1) and hot water extractable B as 0.31 - 1.71 (0.77 mg kg^-1). The fertility ratings categorized based on nutrient index value for different parameters were recorded as low for organic C and available N, medium for available P, S, Zn and B and high ratings for available K, Ca, Mg, Fe, Cu and Mn status.

The block wise statuses of different soil parameters were also monitored in details.

It was estimated that 18.6 % of the total cultivable area (0.270 lakh ha) of the district was found to be under moderately acid soil, 0.582 lakh ha area under low organic C level. More than 70 % area (1.031 lakh ha) with available N, 36% area (0.495 lakh ha) with available P, 30 % (0.436 lakh ha) with available S and 32% area (0.452 lakh ha) with available Zn were observed to be deficient and marked as productivity constraints which are required to manage for the optimum crop production.