Acquisition of an Isotope Facility to Study Atmosphere- Ecosystem Interactions

该项目的重点是建立同位素比质谱仪（IRMS），以解决各种材料中元素（主要是碳，氧，氮和氢）同位素组成的微小差异。 这将有助于从根本上深入了解在较大尺度上控制大气成分的主要生态系统过程，并使人们能够研究几个主要的环境问题，包括全球气候变化和碳循环、辐射活性痕量气体交换、生态系统管理、可持续农业、土壤和水质、保护生物学以及大气和陆地污染。 一些具体问题包括：（1）气候和土地利用的变化如何改变土壤碳储存和化学过程？ (2)在生态系统水平的甲烷通量率和同位素组成中，已知的对甲烷地球化学的控制是如何表现的？ (3)土壤学记录能告诉我们过去气候对土壤形成的影响吗？ (4)管理、生物区系和气候的变化如何改变水文循环？ (5)有蹄类动物的饮食对牧草可获得性和质量的地理差异有什么功能上的依赖性，以及这如何影响消化过程中甲烷的产生？ 最终，该设施将为开发和测试下一代全球和区域环境模型所需的生态系统-大气模型提供关键数据。 该设施将补充科罗拉多州立大学校园和附近的一系列现有实验室和研究小组的现有设施。 科罗拉多州立大学的农业和自然资源学院已经支持为质谱测量准备土壤、水、植物和空气样本所需的实验室，但这些样本现在是在校外分析的。 自然资源生态学实验室维持着对微量气体浓度进行量化的设施。 该设施将作为一块磁铁，促进不同研究小组之间的跨学科合作。 NCAR、北极和高山研究所以及卡内基研究所的合作者将提供互补的专业知识，并将继续利用该设施进行研究合作。

The focus of this project is to establish an isotope ratio mass spectrometer (IRMS) in order to resolve very small differences in the isotopic compositions of elements - primarily carbon, oxygen, nitrogen, and hydrogen - in various materials. This will facilitate fundamental insights into the major ecosystem processes governing atmospheric composition at larger scales, and enable research into several major environmental issues, including global climate change and the carbon cycle, radiatively active trace gas exchange, ecosystem management, sustainable agriculture, soil and water quality, conservation biology, and atmospheric and terrestrial pollution. Some specific issues would include: (1) How are the processes governing soil carbon storage and chemistry modified by changes in climate and land use? (2) How are the known controls over methane biogeochemistry manifested in ecosystem-level methane flux rates and isotopic compositions? (3) What can the pedologic record tell us about past influences of climate on soil formation? (4) How is the hydrological cycle altered as a result of changing management, biota, and climate? (5) What is the functional dependence of ungulate diet on geographic variation in forage availability and quality, and how does this effect methane production during digestion? Ultimately, the facility will provide crucial data for developing and testing ecosystem-atmosphere models needed for the next generation of global and regional environmental models. This facility will complement existing facilities in an array of existing laboratories and research groups on the Colorado State University campus and nearby. The Colleges of Agriculture and Natural Resources at CSU already support laboratories necessary for the preparation of soil, water, plant and air samples for mass spectrometric measurements, but these samples now are analyzed off- campus. The Natural Resource Ecology Laboratory maintains facilities for quantifying trace gas co ncentrations. This facility will serve as a magnet to foster interdisciplinary collaboration among diverse research groups. Collaborators at NCAR, the Institute of Arctic and Alpine Research, and Carnegie Institute will provide complementary expertise and will continue to collaborate in research using the facility.