Temporal and spatial variability of the zooplankton community in Lake Couchiching, Orillia, Ontario: influence of water quality parameters

Abstract

Lake Couchiching, located in Ontario, is a vital freshwater ecosystem providing numerous ecological, recreational, and economic benefits. As human activities and property development increase in the region, it is important to understand their impact on water quality and zooplankton communities. This study explores spatial and temporal variation in water quality parameters and their influence on the structure of zooplankton communities (ZCS) in Lake Couchiching over an annual cycle. Extensive field studies were conducted, and water samples were collected from multiple locations within the lake across various seasons throughout the year. The water quality parameters measured included chlorophyll-a, conductivity, pH, total phosphorus, and nitrate levels. Principal Component Analysis (PCA) identified the primary factors driving variability in the zooplankton community, and cluster analysis grouped similar sampling sites based on water quality characteristics. Both natural factors and human activities drove these characteristics. Conductivity was significantly affected by water quality changes, except in areas directly impacted by effluent discharge from the Orillia Wastewater Filtration Plant. Seasonal variations were observed, with conductivity, total phosphorus, and nitrate levels changing significantly between summer and winter. [...]