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Abstract QuestionsPredicting the influence of climate change on riparian plant communities improves management strategies. The sensitivity of riparian vegetation to climate and other abiotic factors depends on interactions between properties of the ecosystem, like flood regime, and plant characteristics. To explore these interactions, we addressed three questions: (a) does the composition and diversity of riparian vegetation vary with the flood regime; (b) do abiotic correlates of vegetation, including climate and groundwater, differ between sites that flood compared to locations that did not experience floods; and (c) which plant functional groups account for differential plant community sensitivity to abiotic factors between flood regimes? LocationMiddle Rio Grande Valley, New Mexico. MethodsWe used long‐term observations of plant community composition, groundwater depth, precipitation and interpolated temperature from 24 sites spanning 210 km of the Rio Grande riparian cottonwood–willow forest to explore the relative importance of climate and hydrologic correlates of riparian vegetation diversity and composition. ResultsRiparian plant diversity was higher at sites flooding compared to non‐flooding sites. Plant diversity positively tracked shallower groundwater depth at flooding sites, but was best predicted by intra‐annual groundwater variability at non‐flooding sites. Plant community composition correlated with groundwater depth and air temperature at all sites, but at non‐flooding sites, also with intra‐annual groundwater variability and precipitation. Relationships between native plant cover and potential environmental drivers diverged strongly between the two flood regimes; non‐native plant cover had only weak relationships with most environmental predictors. ConclusionsThe current flood regime of a site determined the climate and hydrologic factors that best predicted riparian plant community composition and diversity. Relationships between plant diversity or total cover and groundwater, temperature, precipitation, or groundwater variability can change in strength or direction depending on a site's flood history, highlighting the importance of flood regime to predicting the sensitivity of riparian woodlands to future environmental change.
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Groundwater Well Data from the Middle Rio Grande Valley Riparian Zone, New Mexico (1999-2014)
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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- Award ID(s):
- 1655499
- PAR ID:
- 10424105
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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