Soil organic matter dynamics as affected by long-term use of organic and inorganic fertilizers under maize–wheat cropping system

Abstract

Understanding the effects of long-term use of fertilizers on soil carbon and nitrogen pools and their activities is essential for sustaining soil productivity. Our objectives were to quantify longterm changes in soil organic carbon (SOC), soil microbial biomass carbon (SMBC), soil microbial biomass nitrogen (SMBN) and mineralizable C in maize-wheat cropping sequence in fertilized and unfertilized plots (control, N, NP, NPK, and NPK + FYM). Continuous application of fertilizers increased SOC over its initial content. Active fractions of SOC, i.e., water-soluble carbon, hydrolysable carbohydrates, SMBC, SMBN and dehydrogenase activity, improved significantly with an application of NPK and NPK + FYM. A general increase in carbon mineralization with time period was observed throughout the experiment and was maximum in 100% NPK + FYM treated plots. The estimated annual C input value in NPK + FYM treatment was 1.05 MgC ha -1 year -1 . The overall net change in organic carbon was maximum in treatment receiving FYM along with inorganic fertilizers. Therefore, these results suggest that the integrated use of NPK and FYM is an important nutrient management option for sustaining maize-wheat cropping system.

Effect of Organic Inputs on Strength and Stability of Soil Aggregates Associated Organic Carbon Concentration under Rice-Wheat Rotation in Indo-Gangetic Plain Zone of India

“…Application of organic inputs via soil amendment significantly enhanced the cation exchange capabilities due to the negative charge induced by organic carbon (Weber et al, 2007;Kaur et al, 2008): these capabilities are a very important contributor to detainment of various nutrients from organic inputs and for nourishing agricultural plants. Lastly, organic input can also ensure aggregate stability, as the high stability of aggregation provides favorable conditions for mass transfer, retention time of water, root growth, and microbial activity (Carter, 2002).…”

Improvement in Soil Physical, Chemical and Microbiological Properties during Cropping Cycles under Different Nutrient Managements in Western Himalayas

“…Similar results were obtained in the study done by (Gaiser et al, 2009, Abreu et al, 2011 in which SOC content in soil was increased due to different crop rotations. (Kaur et al, 2008). The total carbon stock in agricultural system also included crop residue input into the soil and in this way it enhanced total carbon stock in agricultural system.…”

Effect of Nitrogen Fertilizer Sources on Grain Yield, Yield Components and Grain Quality of Rice

“…However, N from organic and bio-sources was beneficial to rice plants at the end of season as indicated by the values of studied characters. Application of chemical fertilizer with organic manure was propitious to coordinate the balance of carbon and nitrogen pools, which then increased system productivity (Kaur et al 2007). It is, also, a simple and feasible environment protection.…”