Acquisition of a Stable Isotope Ratio Mass Spectrometer System for Environmental and Paleoclimatic Research

0549633ItoThis grant supports acquisition of a stable isotope ratio mass spectrometer（SIRMS）for environmental and paleocimate research as well as modern ecological studies，hydrology，limnology，and aqueous geochemistry at the University of Minnesota. 将购买一台带有在线外围设备的连续流（CF）质谱仪，自动制备样品并将纯化气体直接引入离子源，取代2001年退役的20年前的Finnigan MAT delta E。 CF-SIRMS将减少需要处理的样品的大小，因此可以对样品序列进行更高分辨率的研究，并提高样品的通量和精度。 将立即受益于所要求的SIMRS能力的研究包括：1）研究美国中部大陆地表水和地下水之间的现代相互作用，如湖泊居住的水生微植物群和动物群的同位素组成所记录的，以及相关的古记录研究，其对了解中部大陆过去的气候变化具有影响; 2）湖泊和湿地的碳平衡研究; 3）通过化石生物磷灰石的稳定同位素分析研究新生代哺乳动物的古食物，并阐明灭绝生物的古环境; 4）基于洞穴沉积物方解石稳定同位素分析的区域第四纪古气候研究。 该工具还将用于培训来自各个部门的博士后和研究生。 为了促进跨学科的工作，每两年将举办一次研讨会，教师和学生将谈论他们的研究，重点是同位素分析的作用。 参加该大学REU项目的本科生将参与使用新仪器的研究。 还将访问印度保留地，并在那里举行关于食物网和水文/沉积物循环的会谈。***

0549633ItoThis grant supports acquisition of a stable isotope ratio mass spectrometer (SIRMS) for environmental and paleoclimate research as well as modern ecological studies, hydrology, limnology, and aqueous geochemistry at the University of Minnesota. A continuous flow (CF) mass spectrometer with on-line peripheral devices that prepare samples automatically and introduce the purified gases directly into the ion source will be purchased, replacing a 20-year old Finnigan MAT delta E that was decommissioned in 2001. The CF-SIRMS will reduce the size of samples needed to be processed and therefore allow higher resolution studies of sample sequences to take place and increase sample throughput and precision. Research that will immediately benefit from the capabilities of the requested SIMRS include: 1) studies of modern interactions between surface and groundwaters in the mid-continental U.S. as recorded in the isotopic composition of the remains of lacustrine dwelling planktonic microflora and fauna and related paleorecords studies with implications for understanding past climate variability in the mid-continent; 2) carbon balance investigations in lakes and wetlands; 3) investigations of Cenozoic mammalian paleodiets through stable isotopic analysis of fossil biogenic apatite with implications for elucidating the paleoenvironments of extinct organisms; and 4) regional Quaternary paleoclimate investigations based on stable isotopic analysis of speleothem calcite. The instrument will be also used to train postdocs and graduate students from a variety of departments. To foster interdisciplinary work, a seminar will be offered every two years where faculty and students will talk about their research, focusing on the role of isotope analyses. Undergraduate students participating in the university's REU program will be involved in research that uses the new instrumentation. Indian reservations will also be visited where talks on the food web and hydrologic/sediment cycle will be presented. ***