Urban and Roehm's research on studying temporary wetlands and associated species was published in the January 2018 Oecologia. It observesthat exurban ponds tend to be designed and managed as permanent waterbodies which retain permanent wetland species but fewer temporary wetland types.
Swamp Forest Exhibit at Crosby Arboretum was designed as a temporary stream corridor
"Exurban areas are expanding throughout the world, yet their
effects on local biodiversity remain poorly understood. Wetlands, in
particular, face ongoing and substantial threats from exurban development. We
predicted that exurbanization would reduce the diversity of wetland amphibian
and invertebrate communities and that more spatially aggregated residential
development would leave more undisturbed natural land, thereby promoting
greater local diversity. Using structural equation models, we tested a series of
predictions about the direct and indirect pathways by which exurbanization
extent, spatial pattern, and wetland characteristics might affect diversity
patterns in 38 wetlands recorded during a growing season. We used redundancy,
indicator species, and nested community analyses to evaluate how exurbanization
affected species composition. In contrast to expectations, we found higher
diversity in exurban wetlands. We also found that housing aggregation did not
significantly affect diversity. Exurbanization affected biodiversity indirectly
by increasing roads and development, which promoted permanent wetlands with
less canopy cover and more aquatic vegetation. These pond characteristics
supported greater diversity. However, exurbanization was associated with fewer
temporary wetlands and fewer of the species that depend on these habitats.
Moreover, the best indicator species for an exurban wetland was the ram’s head
snail, a common disease vector in disturbed ponds. Overall, results suggest
that exurbanization is homogenizing wetlands into more permanent water bodies.
These more permanent, exurban ponds support higher overall animal diversity,
but exclude temporary wetland specialists. Conserving the full assemblage of
wetland species in expanding exurban regions throughout the world will require
protecting and creating temporary wetlands."
Abstract cited from: Urban, M.C. & Roehm, R. Oecologia (2018) 186: 291. https://doi.org/10.1007/s00442-017-3989-y
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