Trophic status of Lake Placid over the past 2740 + 30 years inferred by sub-fossil diatom analysis.
Thu, 04/30/2015 - 11:07
Abstract: The hypothesis of this study was that human activity in the Lake Placid watershed would cause changes in the lakes trophic status. Trophic status was inferred by changes in diatom assemblages over time. This analysis shows that an unusual increase in Asterionella and Tabellaria has occurred within the past 200 years. Both of these species are indicators of higher trophic status, so their increase in numbers indicates a recent increase in trophic status (Stager 2001, Rawson 1956, Stevenson et al, 1982). Loss on ignition tests were used to determine the organic content of samples from two cores. These tests showed that organic content has varied in the past, however changes observed in the upper 20 cm of the record for Lake Placid and Wolf Lake suggest that human activity impacted the lake. The data collected in this study supports the hypothesis that human settlement in the Lake Placid watershed has changed its trophic status.
Literary Rights: On
Major: Environmental Sciences
File Attachments: Trophic status of Lake Placid over the past 2740.docx
Effects of Reduced Turbidity and Suspended Sediment Concentrations on Macroinvertebrate Communities at a Restored Reach on Warner Creek
Fri, 05/01/2015 - 18:21
Abstract: A segment of Warner Creek, a tributary to the Stony Clove Creek in the Catskill Mountains of New York, was restored in 2013 to reduce concentrations of suspended sediment and turbidity caused by a localized mud boil erosion of a large clay bank. Before restoration, impaired water-quality from fine sediments may have adversely affected intolerant species of macroinvertebrates and their communities. This study compared macroinvertebrate assemblages from before (2011) and after (2014) restoration to determine if the restoration reduced concentrations of suspended sediment and turbidity sufficiently to improve the health of their macroinvertebrate communities. The New York State Department of Environmental Conservation (NYSDEC) kick-sample methods were used to collect four replicate benthic invertebrate samples from Warner Creek and from a reference site on the Stony Clove Creek during August of 2011 and August of 2014. Four replicates of 100 specimens were identified to the family level from each replicate. The NYSDEC Bioassessment Profile scores and selected macroinvertebrate community metrics and turbidity and suspended sediment concentrations from a USGS stream gage downstream of the restoration both pre and post restoration were evaluated to test hypotheses that water quality and the health of macro-invertebrate assemblages differed post-restoration. Although some families at Warner Creek with low tolerance values were found to have increased post-restoration, it was also found that others with moderate tolerance values decreased. These types of fluctuations were seen in both years at both Warner Creek and the reference site, which makes it impossible to definitively say the impact restoration had on the macroinvertebrate assemblages one year post restoration. At this time it is obvious from the stream gage data that restoration significantly decreased turbidity and suspended sediment concentrations (SSC). Further collection of invertebrates and stream gage comparison is necessary to see if restoration does eventually impact the assemblage of invertebrates.
Literary Rights: Off
Major: Environmental Sciences
File Attachments: Final Capstone.docx