Effects of elevated CO2 and nitrogen addition on soil organic carbon fractions in a subtropical forest |
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出 版 社:Plant Soil |
发表时间:2012 |
台 站:
鼎湖山森林生态系统定位研究站
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作 者:陈小梅,刘菊秀,邓琦,闫俊华,张德强 |
点 击 率:435525 |
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关 键 字(英文):Carbon fraction . Elevated CO2 . Global climate change . Nitrogen deposition . Soil organic carbon . Subtropical forest |
摘 要(英文):Aims:The aim of this study was to investigate the effects of elevated CO2 concentration and nitrogen addition on soil organic carbon fractions in subtropical forests where the ambient N deposition was high.
Methods:Seedlings of typical subtropical forest ecosystems were transplanted in ten open-top chambers and grown under CO2 and nitrogen treatments. The treatments included: 1) elevated CO2 (700μmol mol-1); 2) N addition of 100 kg NH4NO3 ha-1 yr-1; 3) combined
elevated CO2 and N addition; and 4) control. We measured soil total organic carbon (TOC), particulate organic carbon (POC), readily oxidizable organic carbon(ROC), and microbial biomass carbon (MBC).
Results:Results showed that elevated CO2 alone did not significantly affect soil TOC, POC and ROC after 4 years of treatment, but increased soil MBC and soil respiration compared to the control. N addition alone had no significant effect neither on soil TOC, POC and ROC, but decreased MBC and soil respiration over
time. However, the elevated CO2 and N addition together significantly increased soil POC and ROC,and had no significant effect on soil MBC.
Conclusions:This study indicated that even in N-rich subtropical forest ecosystems, inputs of N are still needed in order to sustain soil C accumulation under elevated CO2. |
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陈小梅-2012-Plant Soil-Effects of elevated CO2 and nitrogen addition on soil organic carbon fractions in a subtropical forest.pdf |