caa a22 4500 605516987 CHVBK 20210128100717.0 cr unu---uuuuu 210128e20150201xx s 000 0 eng 10.1007/s10533-014-0039-2 doi (NATIONALLICENCE)springer-10.1007/s10533-014-0039-2 Elevated atmospheric carbon dioxide concentration stimulates soil microbial activity and impacts water-extractable organic carbon in an agricultural soil [Elektronische Daten] [Huajun Fang, Shulan Cheng, Erda Lin, Guirui Yu, Shuli Niu, Yongsheng Wang, Minjie Xu, Xusheng Dang, Linsen Li, Lei Wang] Carbon dioxide (CO2) enrichment and increased nitrogen (N) deposition can change microbial activity and dissolved organic carbon (DOC) turnover, consequently affecting carbon sequestration in soils. However, we do not have much available information on the relationship between soil DOC and microbial activity under CO2 enrichment and N addition in semi-arid agroecosystems. Using free air CO2 enrichment (FACE), soybean and winter wheat were grown in the field under ambient CO2 (350μmolmol−1) and elevated CO2 (550μmolmol−1) conditions subjected to two N fertilizer regimes (132 and 306kg Nha−1year−1). Rhizosphere soils and bulk soils at three depths, 0-10, 10-20 and 20-40cm, were collected to determine water extractable organic matter (WEOM) characteristics with fluorescence spectroscopy and parallel factor analyses of excitation/emission matrix, as well as five extracellular enzymes activities. All significant effects were observed in the topsoil (0-10cm): elevated CO2 decreased water extractable organic carbon concentration of the rhizosphere soils and bulk soils by 8.5 and 10.1%, respectively. Furthermore, elevated CO2 changed the composition and structure of soil WEOM by increasing the plant- and microbial-derived components in the rhizosphere and solubilizing soil organic matter (SOM). The activities of β-1,4-glucosidase, cellobiohydrolase, phenol oxidase, and peroxidase were stimulated by elevated CO2 in the rhizosphere soils and bulk soils. Our findings suggest that the stimulation of microbial activity elicited by elevated CO2 increased the turnover of labile WEOM and the solubilization of SOM in the topsoils, which could be adverse to the accumulation and stability of soil carbon in the semi-arid agroecosystems in northern China. Springer International Publishing Switzerland, 2014 Free air CO2 enrichment nationallicence Water extractable organic matter nationallicence Excitation-emission matrix spectra nationallicence Rhizosphere priming effect nationallicence Extracellular enzymes activities nationallicence Fang Huajun Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Cheng Shulan University of Chinese Academy of Sciences, 100049, Beijing, China aut Lin Erda Key Laboratory for Agro-Environment and Climate Change, Ministry of Agriculture, 100081, Beijing, China aut Yu Guirui Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Niu Shuli Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Wang Yongsheng Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Xu Minjie University of Chinese Academy of Sciences, 100049, Beijing, China aut Dang Xusheng Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Li Linsen University of Chinese Academy of Sciences, 100049, Beijing, China aut Wang Lei Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut Biogeochemistry Springer International Publishing 122/2-3(2015-02-01), 253-267 0168-2563 122:2-3<253 2015 122 10533 https://doi.org/10.1007/s10533-014-0039-2 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10533-014-0039-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Fang Huajun Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Cheng Shulan University of Chinese Academy of Sciences, 100049, Beijing, China aut NATIONALLICENCE 700 1- Lin Erda Key Laboratory for Agro-Environment and Climate Change, Ministry of Agriculture, 100081, Beijing, China aut NATIONALLICENCE 700 1- Yu Guirui Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Niu Shuli Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Wang Yongsheng Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Xu Minjie University of Chinese Academy of Sciences, 100049, Beijing, China aut NATIONALLICENCE 700 1- Dang Xusheng Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 700 1- Li Linsen University of Chinese Academy of Sciences, 100049, Beijing, China aut NATIONALLICENCE 700 1- Wang Lei Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, Beijing, China aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 122/2-3(2015-02-01), 253-267 0168-2563 122:2-3<253 2015 122 10533