State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China.
Institute of Environment Sciences, Department of Biology Sciences, University of Quebec at Montreal, Case Postale 8888, Succursale Centre-Ville, Montreal H3C3P8, Canada.
Sci Adv. 2020 Mar 18;6(12):eaaw5790. doi: 10.1126/sciadv.aaw5790. eCollection 2020 Mar.
Atmospheric nitrogen (N) deposition affects the greenhouse gas (GHG) balance of ecosystems through the net atmospheric CO exchange and the emission of non-CO GHGs (CH and NO). We quantified the effects of N deposition on biomass increment, soil organic carbon (SOC), and NO and CH fluxes and, ultimately, the net GHG budget at ecosystem level of a Moso bamboo forest in China. Nitrogen addition significantly increased woody biomass increment and SOC decomposition, increased NO emission, and reduced soil CH uptake. Despite higher NO and CH fluxes, the ecosystem remained a net GHG sink of 26.8 to 29.4 megagrams of CO equivalent hectare year after 4 years of N addition against 22.7 hectare year without N addition. The total net carbon benefits induced by atmospheric N deposition at current rates of 30 kilograms of N hectare year over Moso bamboo forests across China were estimated to be of 23.8 teragrams of CO equivalent year.
大气氮(N)沉降通过净大气 CO 交换和非 CO 温室气体(CH 和 NO)的排放影响生态系统的温室气体(GHG)平衡。我们量化了 N 沉降对生物质增量、土壤有机碳(SOC)和 NO 和 CH 通量的影响,最终确定了中国毛竹林生态系统水平上的净 GHG 预算。氮添加显著增加了木质生物质增量和 SOC 分解,增加了 NO 排放,减少了土壤 CH 吸收。尽管 NO 和 CH 通量较高,但在 4 年的 N 添加后,生态系统仍然是净 GHG 汇,为 26.8 至 29.4 兆克 CO 当量公顷年,而没有 N 添加的情况下为 22.7 公顷年。目前中国毛竹林每年每公顷 30 公斤 N 的大气 N 沉降所带来的总净碳效益估计为每年 23.8 兆克 CO 当量。