农田土壤有机碳固定潜力研究进展

土壤有机碳的贮存和损失的研究是目前国际上前沿研究领域之一。研究农田土壤有机碳固定过程 ,对于了解农业生产过程和生态过程的关系具有十分重要的意义。在农田土壤中 ,发生变化的有机碳主要是年轻或轻组有机碳 ,而且土壤有机碳的损失或固定都是在土壤表层和有限的时间内发生 ,且数量巨大。传统的耕作体系是造成土壤有机碳损失的主要原因。为了增加农田土壤有机碳的保有量 ,农业管理措施应该从增加有机碳的输入量 (如草田轮作、保留残茬以及施用肥料等 )和减少土壤有机碳的矿化 (少、免耕等 )两方面入手

Soil organic carbon sequestration potential in cropland

Soil organic carbon (SOC) and its different pools are keys to optimizing crop production, minimizing negative environmental impacts, and thus improving soil quality. Investigation of SOC storage and loss are global foci research subject. The research on soil organic carbon sequestration potential in croplands, is an important way to realize a relationship between agricultural processes and ecological processes. Progresse and problems have been reviewed out in this paper. Cultivation and cropping has led to a substantial loss of SOC from cropland in the world. Land degradation at least partly due to OC loss, and contribution to greenhouse gas emissions from the loss in OC from cropland soil is increasing. Since SOC is heterogeneous in nature, the significance and functions of its various components are ambiguous. It is essential that the relationship between levels of total SOC or the identifiable components and the most affected soil properties be established and then quantified before the amounts of SOC and/or its components can be used as a performance indicator. Furthermore, the environmental role of organic carbon in the soil requires further investigation. Long-term SOC loss often takes place in the topsoil of cropland. Loss of labile components of SOC has been even higher. Management practices that lead to improvement in plant biomass production would likely lead to increased C inputs and hence to increased OC in soil. Compare with intensive agriculture, the adoption of ley-cereal rotation, conservation tillage, and manure applications may reduce soil degradation and sequester carbon.