Breakdown and invertebrate colonization of dead wood in wetland, upland, and river habitats

Breakdown of woody debris in river and upland habitats as well as the interactions between wood and invertebrates have been well described. Studies of wood in wetlands are rare, and far less is known about breakdown and invertebrate use of wood in these transitional habitats. This study experimentally assessed breakdown and invertebrate colonization of wood in a floodplain wetland and directly related patterns in the wetland to adjacent river and upland habitats. Over a 2.7ayear period, we monitored breakdown and invertebrate presence in 10acm diametera x 150acm long sweetgum (Liquidambar styraciflua L.) logs in a floodplain wetland (n = 8), river (n = 5), and upland (n = 4) habitat. Mass loss, decay condition change, and C/N ratios of wetland wood more closely resembled upland than river wood. The overall invertebrate assemblage associated with wetland wood was also more similar to that associated with upland than river wood. Breakdown and invertebrate colonization of wood in the floodplain wetland shared more characteristics with upland than river wood, perhaps because of the seasonal nature of flooding in the wetland. However, the ecology of wood in wetlands also had unique characteristics compared with either the uplands or the river.