Biomonitoring of Near Shore Nutrient Enrichment Using Benthic Algae
Organization: Osoyoos Lake Water Quality Society
The main goal of this project was to assess current or potential near shore nutrient enrichment, and evaluate benthic algal biomonitoring protocols for the use in Okanagan basin lakes. Benthic algae are primary producers and are an important foundation of food webs in rivers and the near shore zones of lakes. These algae possess many attributes that make them ideal organisms to employ in water quality monitoring investigations, as they respond rapidly to shifts in environmental conditions. They also have species-specific environmental tolerances and preferences, and may respond predictably and sensitively to changes in lake conditions such as nutrient enrichment, pH, conductivity, organic contamination, pesticides and many other contaminants. As a result, they are among the most widely used indicators of biological integrity and aquatic ecosystem health. Since benthic algae in lakes live in the near shore zone, they are the first to be affected by watershed changes and their community compositions will reflect this. Therefore, using benthic algae in biomonitoring protocols can potentially provide a more sensitive and earlier warning of near shore water quality impairment than phytoplankton (affected by diluted, open-lake water conditions). With this protocol, simple testing for algae species can provide much information on the relative ‘health’ of near shore areas of lakes – which are most prone to land use impacts, and also considered most important to recreation, tourism and economic development. Approximately 40 sample locations were chosen throughout the Okanagan, on the mainstem lakes (Osoyoos, Skaha, Okanagan, Kalamalka and Wood).