ORGANIC POLLUTION IN URBAN AND RURAL STREAMS IN THE SCHENECTADY-SCHOHARIE REGION OF UPSTATE NEW YORK

The effects of urbanization on water quality in streams is of major concern. Impacts such as reduced water quality, increased erosion, increased habitat loss and reduced biodiversity are widespread. These impacts are often referred to as the ‘urban stream syndrome’. This study evaluates the extent of the urban stream syndrome by comparing rural and urban streams in the Schenectady-Schoharie, NY region. More specifically, this study investigates the presence and source of nitrogen loading to streams in this region. Prior studies have used the δ¹⁵N value of algae as a tracer for the source of nitrogen pollution in both freshwater and marine environments. More specifically, a δ¹⁵N value of 5‰ has been used as a threshold to separate animal generated nitrogen (e.g. sewage and manure) from anthropogenic fertilizers and atmospheric deposition (which have lower δ¹⁵N values). In addition, the N content of algae have been shown to reflect N pollution amounts. During the summer of 2018, water and algae samples were collected from 49 sites along 11 different streams in upstate New York in the Schenectady-Schoharie region. Each site was classified as rural or urban and every type of algae present was collected and classified as either rooted in the sediment, attached to rock, or as filamentous algae. The algae were cleaned, dried, crushed, and packed into tin cups for analysis of stable carbon and nitrogen isotopes. Water samples were analyzed using ion chromatography. The results obtained from this study will be used both in a spatial and temporal analysis. A spatial analysis will reveal the extent of the urban stream syndrome in the Schenectady-Schoharie region. The temporal analysis will make use of data obtained from previous years as well as data obtained from one stream over a four-month period to determine the variability of N pollution over time.