Effect of Long-term Fertilization and Algalization on Active Soil Organic Pools, Crop Yield and Dehydrogenase Activity under Rice- Wheat Cropping Sequences

摘要

The present investigation aimed at understanding the influence of fertilization and algalization on active pools of Soil organic matter (SOM) under continuous rice wheat cropping system. The experiment was carried out with three treatments viz. control (unfertilized), 50% NPKand 50% NPK + BGAin2014 inVertisol at Indira Gandhi Krishi Vishwavidyalaya, Raipur, India. The greater accumulation of soil organic carbon (SOC) in surface soil (0-15 cm depth) than the subsurface soil (15-30 cm) in all three treatments, maximum being in surface soil with treatment 50% NPK + BGA (6.38 g kg"1) followed by 50% NPK (6.13g kg"') and control (4.42g kg"1). The present investigation suggested that long term nutrient management and continuous cropping of two cereals i.e. rice and wheat, caused depletion of soil organic pools including hot water soluble carbon, acid hydrolysable carbohydrate, soil microbial biomass carbon and nitrogen and DHA under no fertilization, whereas; the addition of suboptimal dose of primary nutrients with or without BGA facilitated improvement in soil organic fractions as well as dehydrogenase activity in upper and lower soil profile depth over unfertilized control. The study unveiled that combined application of BGA with fertilizers may be abetter option for crop nourishment and soil health maintenance under rice based cropping system.