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Title: Drivers of ecosystem vulnerability to Corbicula invasions in southeastern North America
Abstract

Invasive species introduction is one of the major ongoing ecological global crises. Identifying factors responsible for the success of invasive species is key for the implementation of effective management actions. The invasive filter-feeding bivalve,Corbicula, is of particular interest because it has become ubiquitous in many river basins across North America and elsewhere. Here we sampled bivalve assemblages, environmental indicators, and land cover parameters in the Ouachita highlands in southeastern Oklahoma and southwestern Arkansas, and in the Gulf Coastal Plain of Alabama to test three working models (using structural equation modeling, SEM) based on a priori scientific knowledge regardingCorbiculainvasions. Our models tested three competing hypotheses: (1) Native mussel declines are related to land use changes at the watershed level and subsequentCorbiculacolonization is a result of an empty niche; (2)Corbiculaabundance is one of the factors responsible for native mussel declines and has an interactive effect with land use change at the watershed level; (3) Native mussel declines andCorbiculasuccess are both related to land use changes at the watershed level. We found no evidence for the first two hypotheses. However, we found that environmental indicators and land cover parameters at the watershed scale were robust predictors ofCorbiculaabundance. In particular, agricultural land cover more » was positively related withCorbiculadensity. These results suggest that further improvement of conventional agricultural practices including the optimization of fertilizer delivery systems may represent an opportunity to manage this species by limiting nutrient inputs to stream ecosystems. Preservation of extensive floodplain habitats may help buffer these inputs by providing key ecosystem services including sediment and nutrient retention.

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Authors:
; ; ;
Award ID(s):
1831512
Publication Date:
NSF-PAR ID:
10366909
Journal Name:
Biological Invasions
Volume:
24
Issue:
6
Page Range or eLocation-ID:
p. 1677-1688
ISSN:
1387-3547
Publisher:
Springer Science + Business Media
Sponsoring Org:
National Science Foundation
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