CLASSIFICATION OF PHYSICO-CHEMICAL PROPERTIES OF SOILS IN ADJOINING OF BIKANER IN RAJASTHAN

Results revealed that the soils were slightly neutral to alkaline in reaction. Percent pH of soil samples varied from location to location and samples (%) were 60.42, 45.83, 70.00, 46.43, 60.42 and 69.64% under 8.5-9.5 soil pH and 2.08, 2.08, 12.50, 12.50, 20.83 and 5.36% under more than 9.5 soil pH at Jorbeer, Gangasahar & Binasar, Hussensar, Napasar, Badrasar and Raisar locations, respectively. Remaining soil samples had a pH < 8.5. The distribution of all soil samples were under low (< 0.5) in organic carbon except 2.08 and 2.50% soil samples were under medium organic carbon at Gangasahar & Binasar and Hussensar, respectively. All the soil samples fall in low availability of nitrogen except 14.58, 4.17, 2.50 and 2.08 per cent of the soil samples at Jorbeer, Gangasahar & Binasar, Napasar and Badrasar were having medium in available nitrogen status, respectively. The available P in the this area of Bikaner districts of Rajasthan was found to be in the order of low i. e. 16.67, 10.42, 22.50, 17.86, 18.75 & 17.86% and 83.33, 89.58, 77.50, 82.14, 79.17 and 82.14% soil samples under medium at Jorbeer, Gangasahar & Binasar, Hussensar, Napasar, Badrasar and Raisar location, respectively. Percent value of available potassium content of surface soils was 5.00, 1.79, 4.17, and 1.79 % under low more than 80 per cent of soil samples (85.42, 83.33, 82.50, 82.14, 89.58, 83.93 at Jorbeer, Gangasahar & Binasar, Hussensar, Napasar, Badrasar and Raisar location) were medium in available K as per critical limits fixed for area of Bikaner districts of Rajasthan. Remaining percent soil samples were 14.58, 16.67, 12.50, 16.07, 6.25, and 14.29% under high at Jorbeer, Gangasahar & Binasar, Hussensar, Napasar, Badrasar and Raisar location, respectively. Considering the critical limit of Fe, 47.92, 58.33, 72.50, 55.36, 62.50 and 69.64 per cent samples were found deficient in available iron. Based on the critical limit of Zn (0.60 ppm), 79.17, 50.00, 87.50, 78.57, 83.33 and 83.93 per cent of samples were found to be deficient in DTPA-extractable Zn at Jorbeer, Gangasahar & Binasar, Hussensar, Napasar, Badrasar and Raisar location and required Zn application for optimum crop production and to get full benefit from NPK fertilization. According to critical limit of Cu 0.2 ppm as deficient (39.58, 33.33, 37.50, 53.57, 7.50 and 39.29 per cent samples at Jorbeer, Gangasahar & Binasar, Hussensar, Napasar, Badrasar and Raisar location, respectively) to sufficient with respect to DTPA extractable copper. In case of Mn, all samples were found sufficient in available Mn in surface soils of around Bikaner city.