Subehia, S.K.SEPEHYA, SWAPANA2016-08-092016-08-092011http://krishikosh.egranth.ac.in/handle/1/71677Doctoral DissertationThe present investigation was carried out to study the effect of integrated nutrient supply on transformation of N, P and K into various chemical pools in the on going long-term fertilizer experiment initiated during 1991 at Bhadiarkhar farm of College of Agriculture, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Palampur in randomized block design with twelve treatments replicated four times. The soil of the experimental site was silty loam and classified taxonomically as “Typic Hapludalf” with acidic reaction, medium in organic carbon, high in available N, medium in P and K at the initiation of the experiment. Surface (0-0.15 m) and sub surface (0.15-0.30 m) soil samples taken after the harvesting of wheat (2008-2009) were analyzed for different forms of nitrogen, phosphorus and potassium. Besides, pH, organic carbon, CEC and available N, P and K were also determined in surface soil samples taken after rice (2008 & 2009) and wheat (2008-09 & 2009-10) using standard methods of analysis. Higher yields and uptake of N, P and K by rice (2008 & 2009) and wheat (2008-09 & 2009-10) were recorded under INM treatments. Continuous application of chemical fertilizers alone or along with organics influenced the different fraction of N, P and K except non hydrolysable-N and non exchangeable-K at both the depths and improved the physical, chemical and microbiological condition of the soil. Integrated nutrient supply proved superior to inorganics. Among nitrogen fractions, hydrolysable ammonical-N was found to be the most dominant, which exhibited highest correlation with soil properties, yield and uptake followed by amino acid-N. Among P fractions, NaHCO3-Pi for soil properties and NaOH-Pi for yield and uptake were important. In case of K, water soluble-K and exchangeable-K were dominant fractions. Continuous cropping without fertilization resulted in depletion in all these fractions.en##Unable to generate tags d3197.pdfFertilizers##Unable to generate tags d3197.pdfSoil ScienceThesis