EAPSI: Stable nitrogen isotopes as indicators of pollution sources in the Yinchuan Plain, China

EAPSI：稳定氮同位素作为中国银川平原污染源的指标

• 批准号: 1414932
• 负责人: Stephani Michelsen-Correa
• 金额: $ 0.51万
• 依托单位: Michelsen-Correa Stephani
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1414932&HistoricalAwards=false
• 关键词: EAPSI; Stable; nitrogen; isotopes; indicators

Over the past 150 years, human activities have doubled the concentration of reactive nitrogen (Nr) entering the terrestrial nitrogen cycle. Excess nitrogen in the environment is detrimental to human health and has been linked to soil acidification, eutrophication, and decreases in biodiversity. China's rapid economic development in the last 30 years has made it the world's largest emitter of Nr. As a result, China is currently experiencing some of the worst pollution problems on Earth. Since Nr affects the soil, water, and air, a better understanding of how nitrogen moves between point sources and ecosystem components is necessary in order to develop strong models for predicting the outcomes of mitigation efforts. This project will investigate the feasibility of using the nitrogen isotope signatures of tree rings, foliage, and soil as indicators of changes in pollution sources and nitrogen uptake of plants in the Yinchuan Plain, China. Due to high pollution levels within the study area, the research will serve as a good case study for testing these methods then potentially applying them elsewhere, including the United States, which also experiences the harmful effects of high reactive nitrogen emissions. The research will be conducted in collaboration with Dr. Hui Qian at Chang'an University in Xi'an, China. Differences in the delta15N signature of tree rings, foliage, and soil have been used to infer changes in the cycling of N in the surrounding ecosystem. Tree ring 15N can indicate changes in the source of N deposition. Additionally, stable isotopes of carbon (delta13C) and oxygen (delta18O) as well as dendrochronological methods will be used to determine if there are changes in the physiological functioning and growth rates of forests in the Yinchuan Plain due to increases in Nr emissions within the valley. This NSF EAPSI award is funded in collaboration with the Chinese Ministry of Science and Technology.

在过去的150年里，人类活动使进入陆地氮循环的活性氮（Nr）浓度增加了一倍。环境中过量的氮对人类健康有害，并与土壤酸化、富营养化和生物多样性减少有关。中国经济在过去30年的快速发展使其成为世界上最大的氮排放国。 因此，中国目前正在经历地球上最严重的污染问题。 由于氮影响土壤，水和空气，更好地了解氮如何在点源和生态系统组成部分之间移动是必要的，以便开发强有力的模型来预测减缓努力的结果。该项目将研究利用树木年轮、树叶和土壤的氮同位素特征作为中国银川平原污染源和植物氮吸收变化指标的可行性。由于研究区域内的高污染水平，该研究将作为一个很好的案例研究，用于测试这些方法，然后可能将其应用于其他地方，包括美国，美国也经历了高活性氮排放的有害影响。 这项研究将与中国西安长安大学的钱惠博士合作进行。 树木年轮，树叶和土壤中的δ 15 N签名的差异已被用来推断周围生态系统中N循环的变化。 树轮15N可以指示N沉积源的变化。 此外，碳（δ 13 C）和氧（δ 18 O）的稳定同位素以及树木年代学方法将被用来确定是否有在银川平原的森林的生理功能和生长速度的变化，由于在山谷内的Nr排放量的增加。NSF EAPSI奖是与中国科技部合作资助的。