Congratulations to Sasha Vinogradova, Cara Gutenberg, and John Buster!
John Buster, PhD,
Washington State University Tri-Cities
Nancy Weller Memorial Scholarship Winner
Estimating decomposition rates of water stargrass (Heteranthera dubia), a potential nitrogen sink in a lowland agricultural river
John is working to understand the role of water stargrass (Heteranthera dubia) in the nitrogen cycle of the lower Yakima River. To better investigate this role, John is conducting whole-plant decomposition experiments of water stargrass (WSG) throughout the Kiona Reach of the Yakima River. These experiments help determine an estimated decomposition rate of WSG, during which nitrogen is released back into the ecosystem with potentially detrimental effects to downstream waterbodies. Future work with this project will incorporate nitrogen concentration analyses of WSG during various stages of decomposition. These experiments and analyses could potentially help watershed managers better understand the role of aquatic plants in the nitrogen cycle.
Hear more about John’s work at this year’s annual conference in Portland.
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Sasha Vinogradova, undergraduate,
University of Washington Tacoma
WALPA Undergraduate Scholarship Winner
Using lanthanum-modified bentonite to immobilize arsenic in lake sediments
Arsenic contamination in aquatic environments is a growing problem that needs modern remediation. Due to the similar chemical structures of phosphorus and arsenic, lanthanum-modified bentonite (LMB), used as a phosphorus treatment in lakes, has been proposed as an arsenic treatment. By creating a mesocosm experiment at Lake Killarney, my research aims to examine the efficacy of LMB as an arsenic treatment, and its effects on arsenic uptake in aquatic organisms.
Sasha will be attending the upcoming conference in Portland and presenting during the poster session.
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Cara Gutenberg, MS,
Western Washington University
Dave Lamb Memorial Scholarship Winner
Nitrogen retention in restored riparian buffers: impacts of stand age
Increased nitrogen pollution from anthropogenic activity threatens human and environmental health by reducing the quality of drinking water and habitats in lakes, streams, and connected nearshore marine ecosystems. Restored riparian buffers can reduce the amount of nitrogen that reaches streams from upland sources through storage in plant biomass and soils. However, quantitative estimates of, and rates of change in, the amount of nitrogen that Pacific Northwest buffers can store in the plant biomass and soil pools are relatively unavailable. Understanding how the sizes of nitrogen pools change as riparian buffers age will provide information on how stand growth influences potential nitrogen retention. This information is essential for the proper parameterization of restoration models, which are used to prioritize restoration efforts. I aim to determine the rates of nitrogen accumulation and how they change in restored riparian buffers over time. I am measuring changes in soil and plant biomass nitrogen pool sizes between 11 restored buffers ranging from one year old to over 100 years old to simulate growth over time. The sampling sites are located in Whatcom County, Washington on either Deer Creek, Squalicum Creek, or Silver Creek. My goal is to better quantify the actual rates (differences in pool sizes/differences in stand age) of nitrogen accumulation over stand development to help parameterize models of watershed nutrient retention under different scenarios of riparian restoration.
