Soil organic carbon dynamics under long-term fertilizations in arable land of northern China
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 warmtemperate 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 to1.461 tha-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-saturated thus have potential to migrate more CO2 from atmosphere.
W.J.Zhang X.J.Wang M.G.Xu S.M.Huang H.Liu C.Peng
Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultura Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830000, China;Eart Inst.of Soil and Fertilizer, Henan Academy of Agricultural Sciences, Zhengzhou, Henan 450002, China Inst.of Soil and Fertilizer & Agricultural sparing water, Xinjiang Academy of Agricultural Sciences, Inst.of Soil and Fertilizer, Jilin Academy of Agricultural Sciences, ChangChun, 130001, China
国内会议
北京
英文
208-224
2010-12-01（万方平台首次上网日期，不代表论文的发表时间）