Multifactor classification of forest landscape ecosystems of Jocassee Gorges, southern Appalachian Mountains, South Carolina

Abstract

Ecosystem classification identifies interrelationships within and among the geomorphology, soils, and vegetation that converge to form ecosystems across forest landscapes. We developed a multifactor ecosystem classification system for a 13 000 ha southern Appalachian landscape acquired in 1998 by the South Carolina Department of Natural Resources. Using a combination of multivariate analyses, we distinguished five ecosystem types ranging from xeric oak (Quercus spp.) to mesic eastern hemlock (Tsuga canadensis (L.) Carrière) ecosystems. Ecosystems segregated along geomorphic gradients influencing potential moisture availability, with soil properties such as solum thickness distinguishing among ecosystems occupying similar topographic positions. Our results suggest that different combinations of geomorphic and soil factors interact to form similar ecosystems across the landscape, and a given environmental factor can impact ecosystem development at some constituent sites of an ecosystem type but not at other sites. A regional comparison of ecosystem classifications indicates that environmental variables important for distinguishing ecosystems in the southern Appalachians vary, with Jocassee Gorges characterized by unique suites of environmental complexes. Our study supports the contention that the strengths of ecosystem classification are providing (i) comprehensive information on the interrelationships among ecosystem components, (ii) a foundation from which to develop ecologically based forest management plans, and (iii) an ecological framework in which to conduct future research on specific ecosystem components or processes.

Vegetation–environment relationships and ecological species groups of an Arizona Pinus ponderosa landscape, USA

“…Ecological species groups often are developed in conjunction with ecosystem classification because species distributions can then be interpreted among environmental gradients treated as continuums or compared among ecosystem types (Archambault et al 1989;Goebel et al 2001;Abella et al 2003). We classified the 66 plots into 10 ecosystem types ( Figure 1) internally similar in environmental and vegetational characteristics detailed in Abella (2005).…”

Elevation and exposition rather than soil types determine communities and site suitability in Mediterranean mountain forests of southern Anatolia, Turkey

“…Although a particular forest ecosystem may contain multiple species compositions during different time periods (Abella et al, 2003), for instance due to human-induced stress or management, spontaneous vegetation still has a high potential for site quality assessment since floral responses to natural abiotic gradients, being the climate, the soil and the geomorphology, have often proved to persist (see e.g. Abella and Covington, 2006).…”

Seed banks of an Arizona Pinus ponderosa landscape: responses to environmental gradients and fire cues

“…The results of these studies suggest that there is potential for seed-bank size and composition to vary as much within a landscape as among biomes. Ecosystem classification, grouping sites that are similar in topography, soil, and vegetation into types across a landscape (Barnes et al 1982;Host and Pregitzer 1992;Abella et al 2003), provides a potentially useful, yet unexplored, framework for examining landscape-scale variation in seed-bank characteristics.…”