氮沉降对毛竹林GHGs排放和净碳汇效应的影响及其机制研究

项目名称： 氮沉降对毛竹林GHGs排放和净碳汇效应的影响及其机制研究

项目编号： No.31270517

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 生物科学

项目作者： 宋新章

作者单位： 浙江农林大学

项目金额： 85万元

中文摘要： 氮沉降既可增加森林的碳汇能力，又可激发温室气体(GHGs)排放，部分抵消了其增汇的功能。毛竹林在全球碳吸存中的巨大潜力及在减缓气候变化中的独特作用日益受到关注，但在日趋严重的氮沉降影响下其净碳汇能力仍不清楚。本项目拟通过观测不同强度氮沉降条件下毛竹林生态系统碳贮量和GHGs通量的变化，阐明氮沉降对毛竹林净碳汇能力的潜在影响，并从植物生产力、凋落物动态、细根周转和土壤呼吸变化的角度揭示氮沉降影响毛竹林生物量碳和土壤有机碳变化的过程机制，从毛竹各部位N含量、C/N比的化学计量学特征角度揭示毛竹林生产力变化的内在可能机理，从土壤WSOC、硝态氮和铵态氮、C/N比、pH值变化等非生物因素和土壤微生物的组成、结构变化等生物因素角度揭示氮沉降作用于GHGs通量的内在可能机理，构建毛竹林生态系统净碳汇效应与氮沉降水平的关系模型，预估未来氮沉降增加情景下我国毛竹林在减缓气候变化中的地位和作用。

中文关键词： 凋落物；土壤微生物；土壤可溶性碳；温室气体；碳吸存

英文摘要： Nitrogen (N) deposition tends to increase the carbon sequestration of forest ecosystem via improving the productivity of forest, but it also arouses the emissions of greenhouse gases (GHGs), including CO2, CH4 and N2O, which partly offsets the carbon benefits of N deposition. The magnitude of these effects is still uncertain. Being a key bamboo species, Moso bamboo (Phyllostachys pubescens) forests in China cover 70% of the country's bamboo forest area and 80% of the total global area of Moso bamboo. With rapid growth and strong carbon sequestration capacity, Moso bamboo forest are receiving increasing attention on the large potential in global carbon uptake and the unique role in mitigating climate change. However, the net carbon uptake effect of Moso bamboo forest at the ecosystem scale under rapidly growing N deposition conditions remains unclear. In this project, we intend to investigate the change in carbon storage and GHGs flux in Moso bamboo forest ecosystem under different level of simulated N deposition, and demonstrate the potential effect of N deposition on net carbon uptake of Moso bamboo forest. The forest productivity, litter dynamics, fine root turnover and soil respiration will be observed to reveal the process mechanism of change in biomass carbon of Moso bamboo forest and soil organic carbon un

英文关键词： Litter；Soil microbe；Soil DOC；Greenhouse gas；Carbon sequestration