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Disturbance and Landscape Dynamics Within the Eastern Deciduous Forest Ecosystem

其他書名	A Case Study in Letchworth State Park
出版	California State University, Northridge, 2012
URL	http://books.google.com.hk/books?id=c6YPngEACAAJ&hl=&source=gbs_api

註釋Despite vast research on forest ecology, persistent investigation is needed to disentangle the dynamic and complex nature of forest ecosystems. Repeat photography and field research were utilized to examine changes in forest structure and composition within Letchworth State Park, located in western New York. Repeat photography was used in observing and qualifying (1) increases in forest density near the Council Grounds, Big Bend Gorge, the Glen Iris, (2) reforestation of the Genesee Valley Canal, (3) moderate increases in vegetation near the Portage Bridge and De-ga-ya-soh Creek Bridge, (4) no significant changes in grasses and shrubs near the Middle Falls, (5) decreases in vegetation resulting from the construction of roads, trails, and viewing areas near the Middle Falls and Portage Bridge and (6) changes in erosional patterns near the Middle Falls "slide area." Field research was used in examining and quantifying the density, frequency, dominance and importance of the species present within four plots: categorized as undisturbed, heavily disturbed, and moderately disturbed. These disturbances were the result of logging that occurred in the park during the nineteenth century. The undisturbed plot was characterized by mature, mid- and late-successional species. In comparison, the plot that was heavily disturbed was characterized by a mixture of early- and late-successional species. The moderately disturbed plots contained the same composition of early-, mid-, and late-successional species. Consistent in both the repeat photographs and field research is the presence of primarily shade-tolerant, late-successional deciduous tree species, signifying a transition towards an overall climax forest ecosystem. The results of this study indicate that anthropogenic disturbances, such as logging and the construction of the Genesee Valley Canal, have influenced forest structure and composition within areas of Letchworth State Park.