Spatio‐Temporal Variation of Chlorophyll‐a in a Drinking Water Reservoir: Role of Hydraulic Conditions and Inflow

Abstract

The temporal and spatial distribution of chlorophyll-a in a shallow drinking water reservoir has been investigated. The chlorophyll-a content in deeper zones varied from vertical stratification to de-stratification during the study period. A higher frequency of occurrence for changes between high and low chlorophyll-a values was found in the middle area of the reservoir compared to the border area. The magnitude of high/low values also differed seasonally and geographically. The reason for the variation of chlorophyll-a in the reservoir was found as a complex result of the influence of water level, nutrients, water depth, temperature, and light as potential factors. The results indicate that the mixing effect triggered by inflow and other hydraulic conditions is one of the important factors influencing temporal and spatial variations of the chlorophyll-a content in the reservoir.