A comparison of lake and river systems within detrital substrate as a determiner of ecoregion stability in Michigan's northern lower peninsula.

Abstract

Various lentic and lotic systems were studied within a watershed and comparisons of algal populations were made between the two systems as an indication of the overall algal composition of the ecoregion. Four samples were taken from a variety of locations and composited to give a good indication of the algal compositions of the study sites. Abiotic factors were determined including: pH, conductivity, temperature and N:P ratios. Results indicate that there is no significant difference in cell densities among the lentic and lotic systems sampled. Further, within the two systems, there are no significant differences among the study sites. Algal abundances at the study sites all reveal that these are diatom dominated systems in terms of FPOM with diatoms comprising 70-80% of algal biomass. Chlorophyll A, an indicator of biomass, values were relatively small a significant difference between lakes and rivers (lakes having higher chlorophyll A values). Based upon both abiotic and biotic factors, the microhabitats can be used as a good determiner of overall ecoregion stability.