文献类型：期刊文献

英文题名：Long-term fertilization increases soil organic carbon and alters its chemical composition in three wheat-maize cropping sites across central and south China

作者：He, Y. T.[1,2] He, X. H.[3,4] Xu, M. G.[1] Zhang, W. J.[1] Yang, X. Y.[5] Huang, S. M.[6]

第一作者：何亚婷;He, Y. T.

通信作者：Xu, MG[1];Zhang, WJ[1]

机构：[1]Chinese Acad Agr Sci, Inst Agr Resources & Reg Planning, Natl Engn Lab Improving Qual Arable Land, Beijing 100081, Peoples R China;[2]Chinese Acad Forestry, Res Inst Forestry Policy & Informat, Beijing 100091, Peoples R China;[3]Southwest Univ, Coll Resources & Environm, Chongqing 400715, Peoples R China;[4]Univ Western Australia, Sch Biol Sci, Crawley, WA 6009, Australia;[5]Northwest A & F Univ, State Key Lab Soil Eros & Dryland Farming, Yangling 712100, Shaanxi, Peoples R China;[6]Henan Acad Agr Sci, Inst Plant Nutr Resources & Environm, Zhengzhou 450002, Henan, Peoples R China

年份：2018

卷号：177

起止页码：79-87

外文期刊名：SOIL & TILLAGE RESEARCH

收录：;EI(收录号：20175004538146);Scopus(收录号：2-s2.0-85037682768);WOS:【SCI-EXPANDED(收录号:WOS:000424073900009)】；

基金：We acknowledge our colleagues for their unremitting efforts to these long-term experiments. This work was supported by the National Natural Science Foundation of China (41371247 and 41571298) and the Fundamental Research Funds for the Central Non-profit Research Institution of CAF (CAFYBB2018QA003). We are grateful to Dr. Daniel Murphy (University of Western Australia, Australia) and Dr. Jingdong Mao (University of Old Dominion, USA) for their assistance in an early version of this manuscript.

语种：英文

外文关键词：NMR; SOC complexity index; SOC decomposition index

摘要：Soil organic carbon (SOC) is at the core of soil fertility. Although fertilization strategies can alter SOC stocks, their effects on SOC chemical composition is less known. Using the solid-state C-13 nuclear magnetic resonance (NMR) spectroscopy, we examined changes in the SOC chemical composition of three soils (0-20 cm depth) from an annual wheat-maize double-cropping system across central to south China. These soils had been subjected to 22 years (1990-2012) long-term fertilization. Compared with no-fertilization control, SOC stocks were significantly increased under chemical fertilization (NPK), NPK plus straw (NPKS), and NPK plus manure (NPKM). The O-alkyl C (labile C), not the alkyl C (persistent C), was consistently increased across the three fertilized treatments. Additionally, all fertilized treatments decreased the ratio of alkyl-C/O-alkyl-C (SOC decomposition index) or aliphatic-C/aromatic-C (SOC complexity index), indicating that the SOC decomposition was delayed, or SOC was converted into a more complicated structure. The soil C of NMR-determined functional groups (alkyl C, O-alkyl C, aromatic C, and carbonyl C) was positively correlated with the cumulative C input (P < 0.05). The conversion rate of functional groups was highest in O-alkyl C, indicating a largest contribution to the increase of SOC accumulation. Soil C:N ratio, pH, and clay were the main factors affecting the functional-group conversion rates, whereas annual precipitation, temperature, and accumulated temperature (> 10 degrees C) played smaller roles. In conclusion, these results can be applied to the improvement of agricultural soil C sequestration capacity through changing SOC chemical structure under long-term fertilizer managements.