| Extensive landscape modification from surrounding land use has led to the decline of riparian forests across North America. An urban-rural gradient was used to assess the impact of land use on riparian forests along the Assiniboine River. Above ground flora and seed bank were examined and species- and guild-level indicators of disturbance identified. Twenty-five sites were categorized according to land use, and included urban, suburban, high intensity rural, low intensity rural, and relatively high quality reference forests. Changes in herbaceous, shrub, and tree species composition and diversity were related to landscape level measures of disturbance that included the proportion of surrounding land use, forest patch size, connectivity, and area:perimeter ratio.; These results suggest that landscape measures of disturbance, and related changes in environment, may be confidently used to assess the impacts of land use along urban-rural gradients. Opportunistic and vulnerable species, and their associated guilds can be used as effective indicators of disturbance and forest integrity and be used to select and monitor forests for further protection or active management. (Abstract shortened by UMI.)... |
