By Marcus Gay, NM WRRI Student Program Coordinator
Stable isotopes are used for identifying water throughout the hydrologic cycle. The isotopic composition of precipitation is often used for identifying water in aquifers, determining the contributions of groundwater and precipitation to streams, and determining the water source for plants and animals. The stable isotopes in precipitation are different in various locations, but even at the same site the stable isotopes will change seasonally. Due to these differences in stable isotopes, precipitation must be collected in every study area where this type of research is being conducted. This allows researchers to identify the stable isotopes of precipitation at each location.
Collecting precipitation can be costly and difficult, especially in semi-arid, arid, and remote locations. Due to the cost and difficulty of collecting precipitation, several studies have attempted to use stream and river water as a proxy for precipitation. Surface water is more accessible and cheaper to collect. If surface water could be used as a proxy for precipitation, it could save a lot of time and money.
Victoria Blumenberg, a PhD student in the Water Science and Management Program at New Mexico State University (NMSU) is conducting a study to determine if surface water can be used as a proxy for precipitation in a semi-arid, mountainous region. Last year, Blumenberg was awarded an NM WRRI student water research grant entitled, Stable Isotope Analysis to Determine the Usefulness of Surface Water as a Proxy for Precipitation in a Semi-Arid, Mountainous Environment.
Under the guidance of her faculty advisor, Dr. Amy Ganguli, Blumenberg has created a surface water study that will couple with a precipitation study that is already underway in northeastern New Mexico. Previous studies of this nature have relied on networks that often have surface water sampling locations far from precipitation sampling locations. This results in large modeling errors that make it difficult to determine the usefulness of surface water as a proxy. The objective of Blumenberg’s study is to use direct comparisons to reduce the errors found in previous analyses. The study will establish surface water collection locations near the existing precipitation collection locations. By partnering surface water sampling sites with the locations of the precipitation collection, this study can compare the results directly and determine if surface water and precipitation have similar isotopic compositions.
The results of the study could help determine if surface water is a suitable replacement for costly, lengthy precipitation studies. If it is determined that surface water is a suitable proxy, more data can be collected to understand how stable isotopes in precipitation change with latitude, elevation, season, and distance from the coast. According to Blumenberg, the results could add to our understanding of how water moves through northeastern New Mexico. She explains, “This research is intended to provide the last piece of the water cycle puzzle in northeastern New Mexico, so we can help producers develop resilient and sustainable water management practices.”
Originally from Cleveland, Ohio, Blumenberg moved to New Mexico from Charlotte, North Carolina. Blumenberg has a Bachelor of Science in Geography with a minor in Earth Science focusing on Geographic Information Systems, and a Master of Science in Earth Science. Her Master’s research involved stable isotopes in groundwater, which is the foundation for the research she is conducting at NMSU. In the future, Blumenberg hopes to work in mitigation of conflicts over water resources.