Walden Pond: Ecological and Anthropological History Reflected in the Sedimentary Record
Tue, 05/03/2016 - 23:13
Abstract: This study examined environmental changes reflected in the microfossil record of a sediment core taken in August 2015 from Walden Pond, Massachusetts spanning the last 600 years. In particular changes in the eutrophication status, inorganic sediment deposition due to land use, lake water depth and temperature were examined using phytoplankton indicator species—diatoms and chrysophytes— to reconstruct environmental conditions. The study site was a basin shallower and closer to the source of anthropogenic N and P inputs than the site of previous studies at Walden’s deepest basin, allowing for finer detection of changes in water level and organic content of sediment. A gravity corer was used to collect the sediment core to preserve topmost sediment layers for analysis, as more than a decade has passed since the last published study of this kind at Walden Pond by Köster et. al. (2005). Results show a significant increase in indicators of eutrophic lake conditions since European settlement ca. 1630, and especially since the 20th century. However, relative Asterionella formosa and Synedra nana abundances had not changed significantly in the last decade since Köster et. al.’s 2005 study, and have in fact decreased somewhat, suggesting water treatment efforts by the Massachusetts Dept. of Environmental Protection (DEP) have had some success. Loss on ignition (LOI) of organic content shows a precipitous decline from the mid 19th century from 37% to 22%, representing intensive land clearance and development until the 1970’s when DEP management began. After that point, LOI rose, perhaps due to increased lake productivity, and has fluctuated around 25%. Relative Discostella stelligera abundance, while used in the WAl-3 piston core as a proxy for water depth, could not be used in the WAL-1 gravity core from this study as eutrophication has significantly impacted their abundance. Chrysophyte scale:diatom ratios corroborate an observed trend of increasing abundance in lakes globally since the 20th century, perhaps in response to rising global temperatures over the same period.
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File Attachments: Capstone Paper.docx
Analysis of Forage Quality in Adirondack Macrophytes: Implications for Waterfowl Nutrition
Fri, 04/29/2016 - 14:48
Abstract: To understand the relative nutritional value of macrophyte food sources for Adirondack waterfowl, the forage quality of four common Adirondack macrophytes were assessed. An analysis of two native pondweeds (Potamogeton) and two invasive watermilfoil (Myriophyllum) was conducted to deduce how invasive and native macrophytes compare in their relative concentrations of nitrogen and mineral content; important indicators of forage quality for waterfowl. Nitrogen content is used as a metric for relative concentration of protein. Macrophyte species were sampled from four Adirondack lakes of the same trophic status to account for effects of lake nutrient characteristics on plant nutrient uptake and synthesis. Total nitrogen was determined with the Kjeldahl procedure using flow injection analysis. Ash (mineral) content was acquired through high-heat burning in a muffle furnace. The invasive watermilfoil species had a higher percentage of nitrogen than the native species. There was no significant difference in the ash content between the species. It is critical to understand the ecological function of these species in relation to wildlife populations. The nutritional value of these aquatic macrophytes may have implications for the fitness and distribution of breeding herbivorous waterfowl in Adirondack lakes. These results may indicate that invasive plants will serve as a viable food source for herbivorous waterfowl as watermilfoil continues to spread across Adirondack aquatic systems.
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File Attachments: Bianca Fournier Capstone Draft 4th Edit.docx
An examination of sustainable agricultural practices of small scale dairy farms in the Adirondack North Country of Upstate New York
Mon, 05/01/2017 - 09:14
Abstract: This study examines the sustainable practices of small scale dairy farms in the Adirondack North Country of Upstate New York. The results of this study can assist farmers in developing and implementing sustainable agriculture practices specific for small scale dairy farms in the North Country. Methods for research include farm tours as well as in person interviews with the farmers which will provide an understanding of what farming practices are currently being implemented as well as identifying what potential practices may be implemented. The information that is gathered can also be helpful with legislative processes. It may provide law makers and various agencies with valuable information that can help create guidelines and regulations that support sustainable farming methods as well as assist farmers in understanding their challenges and successes in reaching both economic and environmental sustainability
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Major: Natural Resources Management and Policy