Presentation Type
Presentation
Faculty Mentor’s Full Name
Ben Colman
Faculty Mentor’s Department
Franke College of Forestry and Conservation
Abstract / Artist's Statement
The North American Beaver (Castor Canadensis), being an ecosystem engineer, played a key role in shaping the North American riparian landscape until they were trapped into near extinction to meet the demands of the fur trade. Their absence has been felt on degraded riparian ecosystems through the incision of streams, which disconnects the channel from the floodplain, as well as through the loss of pool habitat and woody material in incised streams. In the last thirty years, restoration practitioners have sought to bring the benefits of beavers back into these systems through beaver mimicry. Beaver mimicry is the restoration technique of replicating the structure and function of beavers in a landscape through the use of human-constructed beaver dams called beaver dam analogues (BDAs) in order to restore degraded ecosystems. While this technique is relatively cheap, mimics natural events, and might encourage the return of beavers to streams, there is little known about the impacts of BDAs on the organic matter inherent in all streams, despite organic matter making up the base of the riparian food web. In an effort to correct that oversight, I engaged in a study on the impacts of BDAs on dissolved organic matter (DOM) in streams as part of a larger project on BDAs run by PhD student Andrew Lahr in collaboration with the Clark Fork Coalition and The Nature Conservancy. We implemented a BACI (Before, After, Control, Impact) test on three pairs of low-order streams in Western Montana. To answer the question of how these structures impact DOM above and below the dams, I collected and analyzed DOM samples, using levels of protein and humic acid within the samples to indicate the freshness of the DOM present. My results show significant change in these levels over time when looking at individual streams (p0.1). This could suggest that the installation of BDAs on these streams has no impact on the quality of DOM but rather the differences seen are byproducts of the natural progression of these streams. The results from this study come only one year post-treatment, so hopefully with long-term monitoring a more robust pattern will emerge.
Category
Physical Sciences
Being the Beaver- a Dive into Beaver Mimicry and Nutrient Cycling
The North American Beaver (Castor Canadensis), being an ecosystem engineer, played a key role in shaping the North American riparian landscape until they were trapped into near extinction to meet the demands of the fur trade. Their absence has been felt on degraded riparian ecosystems through the incision of streams, which disconnects the channel from the floodplain, as well as through the loss of pool habitat and woody material in incised streams. In the last thirty years, restoration practitioners have sought to bring the benefits of beavers back into these systems through beaver mimicry. Beaver mimicry is the restoration technique of replicating the structure and function of beavers in a landscape through the use of human-constructed beaver dams called beaver dam analogues (BDAs) in order to restore degraded ecosystems. While this technique is relatively cheap, mimics natural events, and might encourage the return of beavers to streams, there is little known about the impacts of BDAs on the organic matter inherent in all streams, despite organic matter making up the base of the riparian food web. In an effort to correct that oversight, I engaged in a study on the impacts of BDAs on dissolved organic matter (DOM) in streams as part of a larger project on BDAs run by PhD student Andrew Lahr in collaboration with the Clark Fork Coalition and The Nature Conservancy. We implemented a BACI (Before, After, Control, Impact) test on three pairs of low-order streams in Western Montana. To answer the question of how these structures impact DOM above and below the dams, I collected and analyzed DOM samples, using levels of protein and humic acid within the samples to indicate the freshness of the DOM present. My results show significant change in these levels over time when looking at individual streams (p0.1). This could suggest that the installation of BDAs on these streams has no impact on the quality of DOM but rather the differences seen are byproducts of the natural progression of these streams. The results from this study come only one year post-treatment, so hopefully with long-term monitoring a more robust pattern will emerge.