Collaborative Research: Disrupted Nitrogen Cycles in the Brazilian Amazon

合作研究：巴西亚马逊地区氮循环中断

• 批准号: 1655432
• 负责人: Christopher Neill
• 金额: $ 20.19万
• 依托单位: Woodwell Climate Research Center, Inc.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2017-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1655432&HistoricalAwards=false
• 关键词: Collaborative; Research; Disrupted; Nitrogen; Cycles

Funds are provided to study nitrogen (N) cycles in the Brazilian Amazon. The research aims at quantifying N transformation and transport pathways in natural and agricultural settings in the Neotropics. The shift in agriculture combined with the increase in nitrogen fertilizer inputs in tropical regions have the potential to drive profound losses of nitrous oxide to the atmosphere, or increased movement of soluble N to rivers and streams. The proposed field research will quantify N2O fluxes and N fate in the vadose zone, groundwater and streams under natural conditions (tropical forest), single cropping of soybeans, and double cropping with soybeans and maize. Remote sensing will be used to scale up results from the field and model to the Amazon region, and incorporation of research results into a dynamic vegetation model (IBIS) that has been parameterized for the Amazon and will be used to estimate N emissions under different climate and land use management scenarios in the future. The work will test two hypotheses: (1) that increased N fertilization will lead to moderately but not greatly higher N2O emissions compared to natural forest because soils are well-drained and are not expected to go anaerobic long enough for accumulation of N2O, and (2) that N losses to streams will be minimal in N-fertilized plots because of high rates of uptake by maize crop and retention of any residual N leachates in deep, clay soils through anion exchange.The research will aid in understanding effects of changing agricultural practices on greenhouse gas emissions and stream pollution in the Amazon. Partnerships with local Brazilian scientists and training of US and Brazilian students will be important impacts from the research. Public outreach and broad dissemination of results will be achieved through regular presentations to agricultural producers and policy makers in Brazil through established contacts, as well as the support of a US journalist to visit the research field sites, which are locations of long-term ecological and biogeochemical research.

提供资金来研究巴西亚马逊的氮（N）周期。该研究旨在量化新型新型技术自然和农业环境中的N转化和运输途径。农业的转移与热带地区的氮肥投入的增加相结合，有可能使一氧化二氮的深远损失向大气，或增加可溶性n向河流和河流的运动。拟议的现场研究将在自然条件下（热带森林），大豆的单个裁剪以及大豆和玉米的双重种植中量化vadose区，地下水和溪流的N2O通量和n命运。 遥感将用于扩大从现场和模型到亚马逊地区的结果，并将研究结果纳入动态植被模型（IBIS），该模型已被参数化，该模型已被参数化，并将用于估计未来不同气候和土地使用管理方案在不同的气候和土地使用管理方面。 The work will test two hypotheses: (1) that increased N fertilization will lead to moderately but not greatly higher N2O emissions compared to natural forest because soils are well-drained and are not expected to go anaerobic long enough for accumulation of N2O, and (2) that N losses to streams will be minimal in N-fertilized plots because of high rates of uptake by maize crop and retention of any residual N leachates in deep,这项研究将有助于理解不断变化的农业气体排放和溪流污染的影响。与当地的巴西科学家以及对我们和巴西学生的培训将是研究的重要影响。通过既定的接触，以及美国记者的支持，可以通过定期向巴西的农业生产者和政策制定者进行定期介绍，以及美国记者参观研究野外现场，这些地点是长期生态和生物地球化学研究的地点，将实现公众的宣传和广泛传播。