Maryland's Green Infrastructure Assessment: Development of a comprehensive approach to land conservation

Like many parts of the US, Maryland is urbanizing rapidly. The scattered pattern of low-density development consumes an excessive amount of land, fragments the landscape, displaces many native species, and disrupts ecosystem functions. Maryland's Green Infrastructure Assessment is a tool developed in the Maryland Department of Natural Resources (DNR) to help identify and rank those areas of greatest statewide ecological importance, as well as those at greatest risk of loss to development. It identifies large contiguous blocks of natural land (hubs), interconnected by natural corridors to allow animal and plant propagule dispersal and migration. Hubs and corridors were ranked within their physiographic region for a variety of ecological and development risk parameters, as well as combinations of these. Prioritization was also done on a finer scale (0.127 ha) for ecological importance and vulnerability to development, allowing a more detailed analysis for site prioritization within the network. The hub and corridor framework identified through the Green Infrastructure Assessment is being used to guide Maryland's ongoing land conservation efforts. At a multi-state scale, the green infrastructure method has been used as the framework for setting landscape ecological priorities within the Chesapeake Bay program. At a regional scale, the method has been used to rank or focus areas for state land conservation programs. Within a local government planning context, the method is now being translated into locally relevant criteria to support county-scale green infrastructure initiatives. Finally, the cell-based ranking method has been incorporated into parcel prioritization that has been used to aid state, local and private land trust conservation decision-making.