Date of Presentation

4-17-2020

Document Type

Poster

College

College of Science & Mathematics

Faculty Sponsor(s)

Michael Grove, Courtney E. Richmond, Nathan Ruhl

Poster Abstract

Zooplankton export from a reservoir is an important indicator of resources in the lotic system below the reservoir and is quantified via count density (DZE), community composition (CCZE), and biomass (BZE). In the study presented here, we monitored DZE weekly between May and August over three years (2017-2019) at a series of four connected reservoirs in Southern New Jersey. Multiple regression indicated that year-to-year differences in DZE were not significant, but DZE did vary over the course of the season and between reservoirs. The best predictor of seasonal variation in DZE was conductivity (a persistent indicator of anthropogenic nutrient pollution). Conductivity was also the best predictor of differences in DZE between reservoirs, with the residual spatial variation between reservoirs being best explained by Colored Dissolved Organic Matter (CDOM). We detected a state-shift in DZE characterized by low week-to-week variation in DZE early in the season at two of the four reservoirs we monitored. Conductivity is the most reliable predictor of DZE both over the course of the growing season and between polymictic reservoirs, but other factors (chlorophyll and nutrient pulses) are more likely to be the causative factors driving variation in DZE.

Student Keywords

Ecological Thresholds, Environmental Indicators, Zooplankton Exports, Polymictic Reservoir Series

Disciplines

Biology

DOI

10.31986/issn.2689-0690_rdw.buss.1003

Included in

Biology Commons

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Apr 17th, 12:00 AM

Ecological Thresholds and Environmental Indicators of the Density of Zooplankton Exports from a Polymictic Reservoir Series

Zooplankton export from a reservoir is an important indicator of resources in the lotic system below the reservoir and is quantified via count density (DZE), community composition (CCZE), and biomass (BZE). In the study presented here, we monitored DZE weekly between May and August over three years (2017-2019) at a series of four connected reservoirs in Southern New Jersey. Multiple regression indicated that year-to-year differences in DZE were not significant, but DZE did vary over the course of the season and between reservoirs. The best predictor of seasonal variation in DZE was conductivity (a persistent indicator of anthropogenic nutrient pollution). Conductivity was also the best predictor of differences in DZE between reservoirs, with the residual spatial variation between reservoirs being best explained by Colored Dissolved Organic Matter (CDOM). We detected a state-shift in DZE characterized by low week-to-week variation in DZE early in the season at two of the four reservoirs we monitored. Conductivity is the most reliable predictor of DZE both over the course of the growing season and between polymictic reservoirs, but other factors (chlorophyll and nutrient pulses) are more likely to be the causative factors driving variation in DZE.