Acquisition of High-Precision Water Isotope Analyzer for Arid-Zone Hydrology

Texas Tech University, Lubbock TX

Investigators

Abstract

Arid and semi-arid zones are expanding and becoming drier due to increasing human activity, agriculture, and climate change. Sustainable development of the southwestern United States, including West Texas, critically depends on creative and efficient use of water resources, which are the most important natural resource to society. The transport of water at and below the surface plays a key role in the water cycle in arid and semi-arid environments. This grant from the National Science Foundation supports the purchase of a high-precision infrared laser spectrometer at Texas Tech University for isotopic analysis of water. This instrument will provide new research opportunities that will lead to better water conservation in these regions. It will also provide undergraduate, graduate and underserved minority students with opportunities to conduct scientifically and socially important research projects as part of their studies. This grant from the National Science Foundation supports the acquisition of a high-precision infrared (IR) laser spectrometer at Texas Tech University for isotopic analysis of water. This instrument is capable of measuring, in addition to conventional &#948;2H and &#948;18O values, the 17O-excess, which is a novel, very useful tracer of water for diffusion-controlled hydrologic processes such as evaporation of water from surface and soil waters. Thus, a combined use of &#948;2H - &#948;18O -17O-excess values can help advance our understanding of the behavior and transport of water in arid and semi-arid zones. To date, high-precision 17O-excess measurements of water have been conducted only by a select few laboratories via highly skilled isotope ratio mass spectrometry. However, recent developments of commercial, high-precision water isotope analyzers enable routine, high-precision measurements of 17O-excess (<15 per meg), in addition to &#948;2H and &#948;18O values. The acquisition of this instrument will benefit several current and future isotope hydrology projects in West Texas and adjacent U.S. southwest regions, involving many researchers from Texas Tech University, and Federal and regional agencies. It will also provide undergraduate, graduate and underserved minority students with opportunities to conduct scientifically and socially important research projects as part of their curriculum. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.