Beneficial Use Impairment #13
BUI #13 - Degradation of phytoplankton and zooplankton populations
Status - Impaired
Phytoplankton and zooplankton are the microscopic plants and animals that are at the base of the food web.
In the Bay of Quinte, phytoplankton and zooplankton species composition has changed over the years, because of reductions in phosphorus inputs and the introduction of invasive species.
Currently, the RAP team is developing a Phosphorus Management Strategy. Studies are being conducted to evaluate how varying reductions in phosphorus levels, recommended in the strategy, will affect the phyto and zooplankton populations in the Bay.
Criteria and Supporting Evidence
1. Associated with the Bay of Quinte RAP phosphorus
reduction targets for the Upper Bay of Quinte, demonstrate that chlorophyll a
concentrations are about 12 μg/L in the Upper Bay of Quinte without the
presence of zebra mussels (with zebra mussel, a further 2-3 μg/L chlorophyll a
reduction should be anticipated). Impaired
2. Demonstrate a positive change in phytoplankton species
composition with a decrease in nuisance and eutrophic indicator species (e.g.,
microcystis, anabaena). Impaired
3. Measure a trend toward a more diverse zooplankton
community shown as a range of mean individual sizes between 0.45 and 0.5 mm for