TRENDY Special Seminar
Dr. Burton V. Barnes
School of Natural Resources and Environment
University of Michigan, Ann Arbor, Michigan USA
±éÂê¡¡ The Landscape Ecosystem Approach and
Fire Ecology in the USA
This seminar has two parts. In the first part, I emphasize the concept and application of the landscape ecosystem approach. Landscape ecosystems (or geoecosystems) are volumetric, structured segments of the Earth's surface. The identification, classification, and mapping of these landscape ecosystems at multiple scales provides the framework for basic scientific research and the conservation, management, and restoration of ecosystems and their parts. I use examples of this approach to illustrate (1) the spatial arrangement of ecosystems, (2) ecosystem diversity, and (3) the conservation of a rare and endangered bird species - the Kirtland's Warbler.
In the second part, I emphasize that fire is the dominant fact of forest history in North America. In every landscape region of the United States, fire has played a major role in the evolution, composition, and dynamics of plant species in regional and local landscape ecosystems. Fire dynamics and fire effects are closely related to the physical and biotic characteristics of site-specific regional and local landscape ecosystems. Because humans have now nearly eliminated wildfire in many parts of the USA, major changes in tree species composition and successional trends are now occurring. In the eastern USA, oak forests are being replaced by those dominated by sugar maple (Acer saccharum), red maple (Acer rubrum), and other mesophytic shade-tolerant species. In the southern USA, pines are being replaced by oaks and mesophytic species. In the Pacific Northwest, Douglas-fir tends to be replaced by western hemlock (Tsuga heterophylla), western redcedar (Thuja plicata), and true firs (Abies spp.)