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This study originated with the objective of parameterizing riparian evapotranspiration (ET) in the water budget of the middle Rio Grande of New Mexico. We hypothesized that flooding and invasions of non-native species would impact the ecosystem's use of water. Our objectives were to measure and compare the ET of native (Rio Grande cottonwood, Populus deltoides ssp. wizleni) and non-native (saltcedar, Tamarix chinensis, Russian olive, Eleagnus angustifolia) bosque (woodland) communities and to evaluate how water use is affected by climatic variability resulting in high river flows and flooding as well as drought conditions and deep water tables. This data set contains water table levels monitored at nine sites along the Rio Grande riparian corridor between Albuquerque and Bosque del Apache National Wildlife Refuge. Data date to 1999. Two sites remain active and are well into their second decade of monitoring. One is in a xero-riparian, non-flooding, saltcedar woodland within the Sevilleta National Wildlife Refuge. The other is in a dense, monotypic saltcedar thicket at the Bosque del Apache NWR that is subject to flood pulses associated with high river flows.
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New water accounting reveals why the Colorado River no longer reaches the sea
Abstract Persistent overuse of water supplies from the Colorado River during recent decades has substantially depleted large storage reservoirs and triggered mandatory cutbacks in water use. The river holds critical importance to more than 40 million people and more than two million hectares of cropland. Therefore, a full accounting of where the river’s water goes en route to its delta is necessary. Detailed knowledge of how and where the river’s water is used can aid design of strategies and plans for bringing water use into balance with available supplies. Here we apply authoritative primary data sources and modeled crop and riparian/wetland evapotranspiration estimates to compile a water budget based on average consumptive water use during 2000–2019. Overall water consumption includes both direct human uses in the municipal, commercial, industrial, and agricultural sectors, as well as indirect water losses to reservoir evaporation and water consumed through riparian/wetland evapotranspiration. Irrigated agriculture is responsible for 74% of direct human uses and 52% of overall water consumption. Water consumed for agriculture amounts to three times all other direct uses combined. Cattle feed crops including alfalfa and other grass hays account for 46% of all direct water consumption.
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- PAR ID:
- 10497504
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Communications Earth & Environment
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2662-4435
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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