Division of Soil Science and Agricultural Chemistry, Indian Agricultural Research Institute, New Delhi, 110012, India.
Environ Monit Assess. 2010 Dec;171(1-4):579-93. doi: 10.1007/s10661-009-1301-2. Epub 2010 Jan 13.
Soil organic matter not only affects sustainability of agricultural ecosystems, but also extremely important in maintaining overall quality of environment as soil contains a significant part of global carbon stock. Hence, we attempted to assess the influence of different tillage and nutrient management practices on various stabilized and active soil organic carbon pools, and their contribution to the extractable nitrogen phosphorus and sulfur. Our study confined to the assessment of impact of agricultural management practices on the soil organic carbon pools and extractable nutrients under three important cropping systems, viz. soybean-wheat, maize-wheat, and rice-wheat. Results indicated that there was marginal improvement in Walkley and Black content in soil under integrated and organic nutrient management treatments in soybean-wheat, maize-wheat, and rice-wheat after completion of four cropping cycles. Improvement in stabilized pools of soil organic carbon (SOC) was not proportional to the applied amount of organic manures. While, labile pools of SOC were increased with the increase in amount of added manures. Apparently, green manure (Sesbania) was more effective in enhancing the lability of SOC as compared to farmyard manure and crop residues. The KMnO(4)-oxidizable SOC proved to be more sensitive and consistent as an index of labile pool of SOC compared to microbial biomass carbon. Under different cropping sequences, labile fractions of soil organic carbon exerted consistent positive effect on the extractable nitrogen, phosphorus, and sulfur in soil.
土壤有机质不仅影响农业生态系统的可持续性，而且对维持环境的整体质量也极为重要，因为土壤中含有大量的全球碳储量。因此，我们试图评估不同耕作和养分管理实践对各种稳定和活跃的土壤有机碳库的影响，以及它们对可提取氮磷硫的贡献。我们的研究仅限于评估农业管理实践对三种重要种植制度（大豆-小麦、玉米-小麦和稻麦）下土壤有机碳库和可提取养分的影响。结果表明，在四个种植周期完成后，综合和有机养分管理处理下的大豆-小麦、玉米-小麦和稻麦的沃克利和布莱克含量略有提高。土壤有机碳（SOC）稳定库的改善与施用有机肥的量不成比例。而添加的有机肥越多，SOC 的易变库就会增加。显然，与厩肥和作物残茬相比，绿肥（田菁）在提高 SOC 的易变性方面更有效。与微生物生物量碳相比，KMnO4 可氧化 SOC 被证明是 SOC 易变库的更敏感和一致的指标。在不同的种植序列下，土壤有机碳的易变部分对土壤中可提取氮、磷和硫产生一致的积极影响。
