Patterns of Succession in Man-Made and Natural Wetlands

Abstract

The response of estuarine benthos to disturbance was investigated to test the hypotheses that season, sediment, composition, and location significantly affect patterns of recolonization. The study was conducted in two creeks, one natural and one mad-made, located in the Pamlico River estuary. Defaunated sediment was exposed 4 times in a temporally overlapping design and sampled after 15, 30, 60, 90, 120, and 210 days. Both site and exposure time and the interactions between these two factors caused highly significant differences in the densities of colonists. With the exception of Hydrobia and chronomid insect larvae, common colonists were more abundant in the natural than in the man-made creek. Differences in patterns of colonization between natural and man-made wetlands may be one factor causing differences in the structure of their invertebrate fauna. The community structure of the disturbed community quickly resembled the ambient community and thereafter temporal patterns of specie’s densities in the ambient and disturbed communities were similar. Gross sediment characteristics had little or no effect on recolonization patterns. These results are preliminary and based on the analyses of only one set of recolonization experiments.