Exotic plant invasions in forested wetlands: effects of adjacent urban land use type

There are a variety of land use types in urbanized areas that may have different effects on the ecological characteristics of patches of natural vegetation. In particular, residential housing and industrial land-use may have different effects on adjacent forest communities. We tested this hypothesis by examining the vegetation of forested wetlands in a densely urban region, northeastern New Jersey. Wetlands embedded in industrial areas were much less invaded by exotic plant species than were wetlands embedded in residential areas, as reflected in the number of exotic species, the fraction of the total flora that was exotic, and their frequencies of occurrence. Few other structural characteristics of the vegetation differed between the two types of urban areas. We suggest that the management of land adjacent to forest edges may explain this surprising result. The low rate of invasion of wetlands within industrial areas suggests they could have high conservation value in urban ecosystems.