Comparing added nitrogen and phosphorous levels to algal biomass and community variances.

Abstract

The following bioassay focuses on changes in stream algal growth due to added nutrients from point and non-point sources of pollution. Nitrogen and/or phosphorus can be limiting factors for algal growth. This investigation uses artificial substrates to deliver nutrient treatments in three Northern Michigan streams. The data suggests significant differences in nutrient induced community change across three treatments that were placed in the Maple River. Nitrogen appears to be the key limiting factor. Phosphorus may be limiting as well. The data include enumeration of macro invertebrates, algal biomass comparisons via chlorophyll a analysis, and qualitative observations of the algal genera that populate the various nutrient substrates.