Ecosystem services have become integral aspects of conservation and natural resource management plans. Hence, understanding historical trends in the spatial distribution of ecosystem services can provide insight for the development of future management plans and conservation efforts. While studies, such as the Millennium Ecosystem Assessment, have evaluated the temporal changes in the flows and stocks of ecosystem services, there is a paucity of studies that have analyzed historical distribution of ecosystem services or how they may change over time. The objective of this study was to analyze the historical spatiotemporal dynamics of three ecosystem services using a framework that could be applied to other ecosystems. Land cover maps for five time periods from the 1930s to the 1990s for the Huron River Watershed, Michigan, USA, were assessed for three ecosystem services: 1) flood disturbance regulation; 2) carbon storage; and, 3) potential wildlife habitat. Ecosystem service indicator metrics for flood disturbance regulation were derived from the California Rapid Assessment Method (CRAM) for Wetlands, for carbon storage from a literature review of regional average values of carbon storage and net annual production, and for wildlife habitat potential from a regional wildlife-landcover matrix.
Results/Conclusions
The spatial distribution of all three ecosystem services changed over the 60 year study. Wetlands providing high quality flood regulation declined throughout the watershed, while there was a significant increase in carbon storage throughout the watershed as agriculture land was converted to forest. Additionally, despite an increase in urban land cover, older forests that had greater carbon storage capacity persisted over the period of study. All wildlife habitats were fragmented over the study period, though there was an increase in percent of landcover classes in the watershed that could serve as habitat for 20 or more species. Mean patch size for different habitat classes were consistent throughout the study period except for land which could serve as habitat for up to 10 species which decreased, and urban areas which increased. Hotspot analysis and correlation of service distribution to urban areas will also be analyzed. This methodology is of notable importance as it is the first spatiotemporal analysis of ecosystems services derived from historical data and because it allows land managers to identify such things as hotspots of ecosystem service in order to make informed decisions on conservation, restoration, and development.