Acquisition of a Stable Isotope Facility to Study Terrestrial Processes and their Interaction with Climate and the Environment

怀俄明大学提议建立一个稳定的同位素比质谱计设施，以研究几个多学科的过程，包括生态系统和大气之间的碳通量、生态系统对模拟气候变化的响应、降水同位素化学模式、使用替代记录重建气候以及环境污染的地球化学。目前，怀俄明州还没有这样的设施。这项建议资助购买一台双进口同位素比质谱仪，用于高精度分析空气、水、土壤和植被中H、C、N、S和O的稳定同位素。该仪器将支持许多正在进行的研究，这些研究利用稳定同位素分析来加强对陆地过程的基本了解。这些措施包括：1)描述本地和农业生态系统的二氧化碳来源和汇活动；2)量化雪深变化改变植物所用水源模式和改变碳通量的程度；3)评估美国各地一系列地点降水的同位素组成的周模式；4)应用植物组织的同位素组成作为古气候指标；5)使用稳定同位素来识别影响地下水污染物的来源和过程，如硝酸盐和有害有机化合物；以及6)表征自由放养的有蹄类动物的季节性觅食模式，并将其应用于重建人类学饮食和捕食策略。拟议设施的主要重点将是促进扩大不同研究团队之间的跨学科合作。此外，该仪器将为高年级本科生、研究生和博士后科学家提供定期接触和研究培训的机会，同时鼓励校园内的其他研究人员将稳定同位素作为他们研究的一部分。最后，该设施将进行分析，这些分析将有助于若干新的国家和国际研究倡议，包括美国对全球降水中的同位素网络(GNIP)和生物圈-大气稳定同位素网络(BASER)的贡献。

A stable isotope ratio mass spectrometer facility is proposed at the University of Wyoming to address several multidisciplinary processes including carbon flux between ecosystems and the atmosphere, ecosystem responses to simulated climate change, patterns of precipitation isotopic chemistry, reconstruction of climates using proxy records, and the geochemistry of environmental contamination. At present, no such facility exists in the state of Wyoming. This proposal funds the purchase of a dual inlet isotope ration mass spectrometer for high precision analysis of the stable isotopes of H, C, N, S, and O in air, water, soil, and vegetation. This instrument will support numerous ongoing studies that utilize stable isotope analyses to enhance a basic understanding of terrestrial processes. These include: 1) delineating the CO2 source and sink activity of native and agricultural ecosystems; 2) quantifying the degree to which changes in snow depth alter the patterns of water sources used by plants and modifies the flux of carbon; 3) assessing the weekly patterns of the isotopic composition of precipitation from an array of sites across the U.S; 4) applying the isotopic composition of plant tissues as paleoclimate proxies; 5) using stable isotopes to identify sources and processes affecting groundwater contaminants such as nitrate and hazardous organic compounds; and 6) characterizing the seasonal foraging patterns of free-ranging ungulates and applying this to the reconstruction of anthropological diets and predation strategies. The major focus of the proposed facility will be to nurture an expansion of interdisciplinary collaboration among diverse research teams. In addition, this instrumentation will provide regular exposure and research training opportunities for upper division undergraduates, graduate students, and postdoctoral scientists while encouraging other researchers on campus to utilize stable isotopes as part of their research. Finally, the facility will perform analyses that will contribute to several new national and international research initiatives, including a U.S. contribution to the Global Network of Isotopes in Precipitation (GNIP) and the Biosphere-Atmosphere Stable Isotope Network (BASIN).