Soil organic carbon dynamics under long-term fertilizations in arable land of northern China

作者：Weijian Zhang, Xiujun Wang, M. Xu, S. M. Huang, H. Liu, Chang Peng · 发表于：Biogeosciences · 年份：2010 · DOI：10.5194/bg-7-409-2010 · 被引用次数：207 · 研究领域：Soil Carbon and Nitrogen Dynamics、Peatlands and Wetlands Ecology、Soil and Unsaturated Flow

Abstract. Soil carbon sequestration is a complex process influenced by agricultural practices, climate and soil conditions. This paper reports a study of long-term fertilization impacts on soil organic carbon (SOC) dynamic from six long-term experiments. The experiment sites are located from warm-temperate zone with a double-cropping system of corn (Zea mays L.) – wheat (Triticum Aestivium L.) rotation, to mild-temperate zones with mono-cropping systems of continuous corn, or a three-year rotation of corn-wheat-wheat. Mineral fertilizer applications result in an increasing trend in SOC except in the arid and semi-arid areas with the mono-cropping systems. Additional manure application is important to maintain SOC level in the arid and semi-arid areas. Carbon conversion rate is significant lower in the warm-temperate zone with double cropping system (6.8%–7.7%) than that in the mild-temperate areas with mono-cropping systems (15.8%–31.0%). The conversion rate is significantly correlated with annual precipitation and active accumulative temperature, i.e., higher conversion rate under lower precipitation and/or temperature conditions. Moreover, soil high in clay content has higher conversion rate than soils low in clay content. Soil carbon sequestration rate ranges from 0.07 to 1.461 t ha−1 year−1 in the upland of northern China. There is significantly linear correlation between soil carbon sequestration and carbon input at most sites, indicating that these soils are not carbon-...