Submitted to: Ecohydrology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 7, 2009
Publication Date: August 10, 2009
Repository URL: http://www3.interscience.wiley.com/cgi-bin/fulltext/122526510/PDFSTART
Citation: Smiley, P.C., Knight, S.S., Shields Jr, F.D., Cooper, C.M. 2009. Influence of Gully Erosion Control on Amphibian and Reptile Communities within Riparian Zones of Channelized Streams. Ecohydrology. 2(3):302-312. Interpretive Summary: Conservation practices that create habitat that is beneficial for amphibians and reptiles are much needed due to worldwide declines currently exhibited by these aquatic animals. Stream channelization frequently causes gully erosion which can reduce the quality of the riparian habitat. Installation of erosion control structures (drop pipes) at the riparian zone - agricultural field interface halts gully erosion and simultaneously establishes one of four riparian habitat types. Because the impact of drop pipes on amphibians and reptiles within riparian habitat is unknown, we compared amphibian and reptile communities found in riparian sites containing actively eroding gullies and each of the four riparian habitat types created by drop pipe installation. Our results show that installation of this conservation practice is capable of creating needed wetland habitats for amphibian and reptile communities. Amphibian and reptile diversity and abundance were the greatest when drop pipe installation resulted in forested riparian wetlands, which suggest that altering the installation design to improve its effectiveness in creating forested riparian wetlands will increase the ecological benefits resulting from this conservation practice.
Technical Abstract: Riparian zones of streams in northwestern Mississippi have been impacted by agriculture, channelization, channel incision, and gully erosion. Riparian gully formation has resulted in the fragmentation of remnant riparian zones within agricultural watersheds. One widely used conservation practice for controlling gully erosion is the installation of drop pipes. This practice involves placing earthen dams across eroding gullies and embedding a metal standpipe within the dam to convey water from the field to stream level. Installation of this structure halts gully erosion and incidentally replaces eroding gullies with riparian habitats. Previous research evaluating gully erosion control structures have not considered the ecological impacts of these conservation practices on amphibian and reptile communities. We compared amphibian and reptile communities among riparian sites containing actively eroding gullies and four riparian habitat types created by drop pipe installation. Amphibians and reptiles were sampled from four gullies and four sites of each drop pipe created habitat type from 1994 to 1996. Amphibian and reptile diversity and abundance were the greatest in created habitat types with mean habitat areas > 1000 m2 and mean pool volumes > 420 m3. Amphibian and reptile diversity and abundance within created riparian habitats were also positively correlated with hydrology. Our results suggest the use of drop pipes to control gully erosion is capable of creating needed riparian wetlands for amphibian and reptile communities. Additionally, altering the installation design will increase the ecological benefits resulting from this conservation practice.