Affiliation:
1. US Geological Survey, Wetland and Aquatic Research Center, Lafayette LA, USA
2. US Fish and Wildlife Service, Upper Gulf Coast Zone, Inventory & Monitoring, Texas, USA
Abstract
AbstractBackground and AimsCoastal wetlands have evolved to withstand stressful abiotic conditions through the maintenance of hydrologic feedbacks between vegetation production and flooding. However, disruption of these feedbacks can lead to ecosystem collapse, or a regime shift from vegetated wetland to open water. To prevent the loss of critical coastal wetland habitat, we must improve understanding of the abiotic–biotic linkages among flooding and wetland stability. The aim of this research was to identify characteristic landscape patterns and thresholds of wetland degradation that can be used to identify areas of vulnerability, reduce flooding threats and improve habitat quality.MethodsWe measured local- and landscape-scale responses of coastal wetland vegetation to flooding stress in healthy and degrading coastal wetlands. We hypothesized that conversion of Spartina patens wetlands to open water could be defined by a distinct change in landscape configuration pattern, and that this change would occur at a discrete elevation threshold.Key ResultsDespite similarities in total land and water cover, we observed differences in the landscape configuration of vegetated and open water pixels in healthy and degrading wetlands. Healthy wetlands were more aggregated, and degrading wetlands were more fragmented. Generally, greater aggregation was associated with higher wetland elevation and better drainage, compared with fragmented wetlands, which had lower elevation and poor drainage. The relationship between vegetation cover and elevation was non-linear, and the conversion from vegetated wetland to open water occurred beyond an elevation threshold of hydrologic stress.ConclusionsThe elevation threshold defined a transition zone where healthy, aggregated, wetland converted to a degrading, fragmented, wetland beyond an elevation threshold of 0.09 m [1988 North American Vertical Datum (NAVD88)] [0.27 m mean sea level (MSL)], and complete conversion to open water occurred beyond 0.03 m NAVD88 (0.21 m MSL). This work illustrates that changes in landscape configuration can be used as an indicator of wetland loss. Furthermore, in conjunction with specific elevation thresholds, these data can inform restoration and conservation planning to maximize wetland stability in anticipation of flooding threats.
Funder
USFWS NWR System
USFWS Science Applications
USGS Science Support Program
USGS Ecosystems Program
USGS LandCarbon Program
USGS Land Change Science R&D Program
Publisher
Oxford University Press (OUP)
Reference67 articles.
1. Ecological thresholds and regime shifts: approaches to identification;Andersen;Trends in Ecology and Evolution,2008
2. The value of estuarine and coastal ecosystem services;Barbier;Ecological Monographs,2011
3. Vegetation recovery in tidal marshes reveals critical slowing down under increased inundation;van Belzen;Nature Communications,2017
4. Trimble RTX, an innovative new approach for network RTK;Chen;Proceedings of the 24th International Technical Meeting of the Satellite Division of the Institute of Navigation. ION GNSS-2011,2011
5. Elevated CO2 enhances biological contributions to elevation change in coastal wetlands by offsetting stressors associated with sea-level rise;Cherry;Journal of Ecology,2009
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