Interannual controls on riparian plant health in a dryland river DOI Creative Commons
Peter W. Downs, Adam Lambert, Jared Williams

et al.

Ecohydrology, Journal Year: 2024, Volume and Issue: 17(2)

Published: Jan. 5, 2024

Abstract Riparian zones in drylands provide important refugia for plants but depend on groundwater and thus are subject to local temporal spatial variability abiotic controls. In lieu of costly field‐based sampling, we used readily available data establish site–scale interannual relationships among riparian plant health the factors that control their water balance a historically persistent wetland adjoining Santa Clara River southern California, USA. Non‐linear generalized additive model (GAM) analysis health, represented using normalized difference vegetation index (NDVI), confirmed robust various geomorphological hydrological over multi‐decadal timeframes, including years since last high‐flow event, intra‐year elevation changes magnitude 2‐year cumulative surface inflows. Geomorphic controls related with high flows cause extensive scour deposition re‐set communities. Relationships dry‐season declines reflect direct access sub‐surface moisture. Hydrological dependence via inflow indicates dependency elevations sufficient winter recharge prevent precipitous decline. GAMs‐based inflection point inflows versus multi‐year is critical avoiding catastrophic large flood events drive recovery. We show can be derived from non‐linear better represents complexity these scalar Our has relevance ecosystem management human‐altered rivers climate change adaptation.

Language: Английский

Interannual controls on riparian plant health in a dryland river DOI Creative Commons
Peter W. Downs, Adam Lambert, Jared Williams

et al.

Ecohydrology, Journal Year: 2024, Volume and Issue: 17(2)

Published: Jan. 5, 2024

Abstract Riparian zones in drylands provide important refugia for plants but depend on groundwater and thus are subject to local temporal spatial variability abiotic controls. In lieu of costly field‐based sampling, we used readily available data establish site–scale interannual relationships among riparian plant health the factors that control their water balance a historically persistent wetland adjoining Santa Clara River southern California, USA. Non‐linear generalized additive model (GAM) analysis health, represented using normalized difference vegetation index (NDVI), confirmed robust various geomorphological hydrological over multi‐decadal timeframes, including years since last high‐flow event, intra‐year elevation changes magnitude 2‐year cumulative surface inflows. Geomorphic controls related with high flows cause extensive scour deposition re‐set communities. Relationships dry‐season declines reflect direct access sub‐surface moisture. Hydrological dependence via inflow indicates dependency elevations sufficient winter recharge prevent precipitous decline. GAMs‐based inflection point inflows versus multi‐year is critical avoiding catastrophic large flood events drive recovery. We show can be derived from non‐linear better represents complexity these scalar Our has relevance ecosystem management human‐altered rivers climate change adaptation.

Language: Английский

Citations

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