Chronic Nitrogen Additions to Forest Ecosystems: Effects of Nitrogen Cycling, Canopy Chemistry, and Trace Gas Emissions

森林生态系统的长期氮添加：氮循环、冠层化学和痕量气体排放的影响

• 批准号: 9108565
• 负责人: John Aber
• 金额: $ 40万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-09-01 至 1993-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9108565&HistoricalAwards=false
• 关键词: Chronic; Nitrogen; Additions; Forest; Ecosystems

This research project will concentrate on continuing the Nitrogen additions in both the hardwood and red pine stands, and measuring basic N cycling parameters such as mineralization, nitrification, and plant uptake, including green foliar content. The project will also estimate N return to the system in litter fall and litter decay. As well, trace gas fluxes (CO2, N2O, CH4) will be measured. It is hypothesized that trace gas fluxes are controlled to a significant degree by short-term availability of carbon and nitrogen to soil microbes, and that these availabilities are, in turn, constrained by feedbacks between soil availability and plant demand. The effects of N additions on gross and net N immobilization and mineralization, on the production and consumption of available carbon during litter and soil organic matter decay, and on the available carbon and inorganic nitrogen content of throughfall will be investigated.

该研究项目将集中于继续氮 在硬木和红松林中添加，并测量 基本的氮循环参数，如矿化，硝化， 和植物吸收，包括绿色叶含量。 项目 还将估计N返回到系统中的凋落物， 垃圾腐烂。 此外，痕量气体通量（CO2，N2O，CH4）将 测定了 假设痕量气体通量被控制在 短期内可获得的碳和 氮对土壤微生物，这些可用性，在 反过来，受到土壤可用性和 植物需求。 增施氮肥对土壤总氮和净氮的影响 固定化和矿化，对生产和 凋落物有效碳消耗量与土壤有机质 物质衰变，并对有效碳和无机氮 将调查穿透雨的含量。