A Landscape Development Intensity Index Map of Maryland, USA
Denis White 1, Daniel Campbell 2, Laura Jackson 3 and Patricia Bradley 2
1 US Environmental Protection Agency, Corvallis, Oregon
2 US Environmental Protection Agency, Narragansett, Rhode Island
3 US Environmental Protection Agency, Research Triangle Park, North Carolina
We present a map of human development intensity for central and eastern Maryland using an index derived from energy systems principles. Brown and Vivas developed a measure of the intensity of human development based on the nonrenewable energy use per unit area as an index to explain the condition of human and ecological systems on the landscape. They called this measure the Landscape Development Intensity Index (LDI). This index uses Odum's concept of emergy as the common currency for relating different kinds of energy use. In this study we used a top down method to estimate the average annual emergy flow that is characteristic of each category of land use category. For each such land use category in Maryland, we have calculated the renewable and nonrenewable emergy flow per hectare per year using the new method. From these data we can make a pixel level map for our study area in Maryland or a map at any level of aggregation of pixels, for example, political jurisdictions, census units, hydrological accounting units, or ecological regions. Such maps are the basis for spatially explicit emergy analyses of environmental problems at any scale.