Distribution of metals in fauna, flora and sediments of wet detention ponds and natural shallow lakes

Fauna, flora, and sediment were collected from 9 wet detention ponds receiving stormwater runoff and 11 small natural shallow lakes. The fauna and flora samples were sorted into species or groups of species and, together with sediments, analyzed for aluminum, copper, iron, zinc, arsenic, cadmium, chromium, nickel, lead, and phosphorus. There was a trend toward the studied wet detention ponds being more polluted by metals than the lakes. For the fauna this trend was statistically significant for all metals, while it for the plants was statistically significant for most of the metals. For the sediments, however, this observed trend was not statistically significant for any of the metals. Comparing the different metals accumulated in the sediments, the fauna, and the flora, no correlation between any of these could be detected. Neither fauna nor flora metal concentrations did correlate with sediment metal concentrations, and fauna metal concentrations did not correlate with flora metal concentrations. Comparing the diversity of species in the wet detention ponds and the shallow lakes, molluscs were more abundant in the wet detention ponds. For other fauna and flora, no clear difference between the diversity of species was observed.