Deforestation, Reforestation and Forest Fragmentation on the Upper Coastal Plain of South Carolina and Georgia
Pinder, J. E., III, Rea, T. E., Funsch, D. E., The American Midland Naturalist
ABSTRACT.-Rates of deforestation and reforestation were measured using Landsat Multispectral Scanner data for a 100-km by 100-km section of the Upper Coastal Plain of South Carolina and Georgia. Landsat data from 1974, 1979, 1984, 1988 and 1991 were (1) classified as pine forest, hardwood forest and nonforested areas and (2) compared across years to indicate forest cutting and regeneration. In 1974 hardwood forests occurred on 268,335 ha, or 27% of the area, and these forests were largely uncut in subsequent years. In 1974 pines occurred on 202,613 ha, or 20% of the area, but cutting rates of approximately 6600 ha y^sup -1^ reduced the area of this initial pine forest to 110,146 ha in 1988 and 82,795 ha in 1991. The rate of pine cutting on privately owned land was 4.0% y^sup -1^, which is greater than that observed for most tropical forests. Pine reforestation rates were 3200 ha y^sup -1^ and were too small to maintain the area in pine. The total pine area in 1988, including remnants of the 1974 forest and reforestation since 1974, was 155,559 ha, or 77% of that in 1974. The rapid rate of loss of pine habitat indicated by the Landsat data was not apparent in the United States Forest Serice (USFS) surveys for the same region and time. This discrepancy is due to methodological differences between USFS procedures, which measure forests as product resources, and the Landsat data, which measure forests as habitat area.
Studies of deforestation and forest fragmentation are common for areas where old-growth forests are being harvested for wood products (e.g., Green and Sussman, 1990; Spies et al., 1994; Reed et al., 1996; Chatelain et al., 1996) or converted to agricultural use (e.g., Skole and Tucker, 1993; Alves and Skole, 1996; Fensham, 1996). Many of these studies involve tropical areas because most old-growth forests have already been removed from most temperate systems.
The history of deforestation in temperate systems is well-documented for the southeastern United States where the original > 20,000,000 ha of pre-Columbian forest in South Carolina and Georgia was reduced to approximately 1,000,000 ha by the 1920s (Ahern, 1933) and to small remnants by the 1980s (Jones, 1988; Walker, 1991; Devall and Remp, 1992; Nowacki and Trianosky, 1993; Davis, 1996). As the pre-Columbian forests were cut various secondary forests formed and were harvested until the maximum conversion of forests to farmland occurred in the 1920s (Sharitz et al., 1992). The forested area increased during the 1930s due to the collapse of cotton agriculture and the conversion of farmland to pine forests through either natural succession or artificial reforestation (McQuilkin, 1940; Oosting, 1942; Durish and Macon, 1951; Cowell, 1998). Forested area increased more in the Mountains, Piedmont and Lower Atlantic Coastal Plain than in the Upper Atlantic Coastal Plain (hereafter UCP). Forests became the predominant land cover in all regions except the UCP where agriculture remained the predominant land use (Hodler and Schretter,1986; Kovacik and Winberry, 1987; Turner and Ruscher, 1988).
Because most reforestation in the South occurred on abandoned agricultural fields, most forested areas are on privately owned land (Alig et al., 1986; USDA, 1988; Sharitz et al., 1992). More than 60% of the forested land on the UCP of South Carolina and Georgia is owned by private individuals (Tansey, 1987a; Thompson, 1989b), and < 0.1% is in National Forests. The only large, federally owned lands are military bases and the U.S. Department of Energy's Savannah River Site (hereafter SRS) which is a 81,232 ha nuclear-weapons production facility whose extensive forested areas are managed by the U.S. Forest Service (hereafter, USFS).
The large proportion of UCP forest in private ownership presents problems in the management and maintenance of forest resources due to (1) the importance of economic forces in determining the fate of privately-owned forests (Alig et al. …