PARENT SESSION
Symposium 9: Spatial heterogeneity in urban ecosystems: Integration and scaling in coupled natural-human systems
Organized by: ML Cadenasso, M Grove, and STA Pickett
Tuesday, August 9, 1:30 PM - 5:00 PM, Meeting Room 517 C, Level 5, Palais des congrès de Montréal
Reconceptualizing land cover in urban areas: A novel approach for spatial integration.
Cadenasso, Mary1, Pickett, Steward2, 1 Hixon Center for Urban Ecology, New Haven, CT, USA2 Institute of Ecosystem Studies, Millbrook, NY, USA
ABSTRACT- Cities are coupled human-natural systems and are characteristically heterogeneous. To understand cities as ecosystems, the heterogeneity of the system must be described and quantified so that system structure can be linked to ecosystem function. Land use and land cover are frequently used as coarse descriptors of landscape heterogeneity. Available classifications, however, are inadequate to capture the coupled nature of urban areas and their heterogeneity. Therefore, traditional views of land use/land cover need to be reconceptualized for application to an urban system. We have developed a novel classification for urban systems that is focused on land cover. In this new system, termed HERCULES (High Ecological Resolution Classification for Urban Landscapes and Environmental Systems), land cover is classified based on the arrangement of built structures, vegetation, and impervious surfaces. Unique combinations of these three elements define the integrated classes. The cover and type of each element is allowed to vary independently of the other elements, giving the classification the flexibility needed to characterize complex coupled systems. HERCULES has been tested in the Gwynns Falls watershed, the research watershed of the Baltimore Ecosystem Study, LTER. We analyze the difference in understanding of system structure achieved by using HERCULES versus using traditional land use/land cover classifications. We also demonstrate how the use of HERCULES improves relationships between the structure and function of the ecosystem by evaluating whether the different classification approaches to land cover differ in their relationship to water quality in four catchments of the Gwynns Falls watershed and a reference watershed.
Key words: urban, heterogeneity, land cover, water quality