IRES: Responses of dryland agroecosystems to the compounding effects of climate variability, human intervention and the critical zone architecture on their hydrologic dynamics

University Of Texas At El Paso, El Paso TX

Investigators

Abstract

This project investigates the impact of extreme weather events such as droughts and heatwaves on the water use efficiency and productivity of perennial croplands growing along dryland rivers of the Chihuahuan desert. The study focuses on pecan trees (Carya illinoinensis), which represent a major socioeconomic driver of the US-Mexico binational region and are particularly vulnerable to water scarcity and declining water quality. The study examines how variations in leaf-level traits of trees growing on different soils influence their use of water and how those variations make them more or less susceptible to stress conditions from extremely hot and dry weather. By looking at the effect of weather extremes on the daily functioning of trees at the level of their leaves (how they change their transpiration and photosynthetic activities) together with historical analyses of tree growth variations from tree rings, the study looks to disentangle the impact of soil water availability and weather conditions on limiting the growth and productivity of these important crops. The knowledge generated through this project will enable farmers to better understand the water use patterns of these perennial crops as they respond to challenging weather conditions, potentially leading to enhanced management practices and increased resilience of agriculture in the U.S.-Mexico binational region. This project employs a multi-temporal, multi-scale, and multidisciplinary approach, to identify tree responses to abiotic stressors, including soil moisture availability, temperature, and air dryness by integrating micrometeorology, dendrochronology, hydrology, plant physiology, plant genomics and hydrogeochemistry analyses. Additionally, through this project, a cohort of 24 undergraduate students (6 per year for 4 years) is being trained for periods of ten weeks during the height of the growing season. This training occurs in a multidisciplinary setting in one of the areas in North America experiencing severe water and heat stress and exposes the students to the cultural intricacies of binational water resources management. Non-NSF funded collaborators from foreign institutions are training, supervising and mentoring the cohort of U.S. students as well as facilitating the material resources needed to conduct their research while in Mexico. In addition to receiving instruction on data collection, analysis and presentation of their scientific results, through this work, the students are gaining a deeper understanding of water management challenges specific to the binational region and practical skills associated with current efforts for improved water conservation and sustainable agricultural practices. 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.