B.S.MathurShailendra Kumar Singh2024-06-222024-06-221989https://krishikosh.egranth.ac.in/handle/1/5810210775The present project was undertaken to assess the changes brought out by the cumulative effect of manure, lime, sulphur and fertilizers, after 15 years of continuous application, on status of major nutrients, different forms of aluminium, phosphate fixing capacity etc. in surface and subsurface layers. The important findings are summarised below : 1.The fine particles in the surface and subsurface soil increased without affecting the textural class clay loam. 2. Fertilized soils were more reddish than the control and the colour did not change due to continuous cropping. 3. Acidity increased in surface and subsurface soil in fertilized plots and it was more in ammonium sulphate than the urea treated soil on equal nitro gen basis. Acidity increased with time. Treatment N was more acidic than NP and NPK. 4. With the increase in soil acidity all forms of Al also increased from the initial value in both the layers. 5. P-fixing capacity of soils increased with increase in soil acidity. 6. Organic carbon level of surface soil increased by 15.5 per cent over the initial value after 6 years of continuous application of FYM but decreased after 10 years. Use of chemical fertilizer lowered its level ranging between 4.9 and 29.6 per cent Organic carbon content in the surface was not affected. soil 7. Available N, P and K increased in surface and subsurface soils with passing of time. 8. Normal dose of NPK was better than subnormal or super-normal doses. Urea proved better than ammonium sulphate in increasing the yield of crops. 9. NPK was better than N, NP or PK in increasing the yield of crops.EnglishThesis