Repeated annual applications of fertilizers and seeding systems affect crops, soil, and soil moisture

Description

Soil test based fertilizer use is sustainable and economical to optimize crop production and profit. But most farmers doubt its effectiveness. Book discusses test studies on temporal responses of residual and recommended nutrient amounts, crops (seed yield, roots, soil moisture use) and soil properties to repeated use of soil test based fertilizer rates (0 to 140%) on dry land crops for six years under two tillage systems, and related literature. After low yield crops, fertilizer increased residual nitrate N, available P, extractable K and sulphate S amounts, with a temporal trend for P, and reduced recommended N, P and S fertilizer amounts. Residual nutrients were effectively used by subsequent crops without sacrificing seed yield. Increase in relative seed yield by fertilizer became greater with years of fertilization. Fertilization increased stratification of P, Ca, Mg, pH and OM. Fertilizer increased soil OM, aggregation, water use by crops, and root length, surface area, volume and tips. Soil testing can optimize fertilizer use to enhance crop yields and water use.