Effects of changes in throughfall on soil GHG fluxes under a mature temperate forest, northeastern China
Effects of changes in throughfall on soil GHG fluxes under a mature temperate forest, northeastern China
复制标题
中国东北温带成熟森林下径流变化对土壤温室气体通量的影响
DOI：
10.1016/j.jenvman.2021.112950
复制
发表时间：
2021
影响因子：
8.7
通讯作者：
Han Lin
中科院分区：
文献类型：
--
作者：
Xu Xingkai;Duan Cuntao;Wu Haohao;Luo Xianbao;Han Lin
Climate change scenarios predict a change in the rainfall regimes for this current century, which has different impacts on soil greenhouse gas (GHG) fluxes. However, how changes in annual rainfall affect annual GHG fluxes of forest soils remain unknown. A six-year field experiment with −25% and −50% throughfall (TF) and +25% TF manipulation was performed to explore the mechanisms involving GHG fluxes under a mature temperate forest, northeastern China and to work out whether the TF effect sizes on annual soil GHG fluxes vary with dry and wet years. The results showed that both −25% TF and −50% TF treatments depressed annual soil nitrous oxide (N2O) and carbon dioxide (CO2) emissions but increased annual soil methane (CH4) uptake. A contrary pattern of annual soil GHG fluxes was observed in the +25% TF treatment. When annual TF input was decreased by 100 mm, annual soil N2O and CO2emissions were decreased by 18.1 ± 3.1 mg N m−2and by 39.4 ± 6.1 g C m−2during the growing season, respectively, and annual soil CH4uptake was increased by 11.5 ± 3.4 mg C m−2. Both −25% TF and −50% TF treatments reduced annual soil dissolved organic C (DOC) leaching by 29.3% and 45.6% and dissolved total N (DN) leaching by 30.8% and 39.6%, respectively. Contrary to annual soil N2O and CO2emissions, annual soil CH4uptake during the growing season significantly decreased with an increase in the annual leaching fluxes of soil DOC, inorganic N, and DN. Besides soil moisture and temperature and pH, soil GHG fluxes under manipulating TF condition were regulated by soil labile C and N status. Our findings indicated that the TF effect sizes on both annual GHG fluxes and net annual GHG balance (GWP) of forest soils varied with dry and wet years in northeastern China. The results highlight the importance of altered annual rainfall in regulating annual soil GHG fluxes and the GWP in temperate forests under global climate change.
