| Summary: | 博士 === 國立臺灣大學 === 森林學研究所 === 91 === Study on the process of ecosystem succession and its relevant conservation strategies is one of the most important purposes of long-term researches in nature reserve. Owing to the fact that timbers are the dominant species of forest ecosystem, the vegetation dynamics must be discussed as one of the first step of forest ecosystem succession research. A forest ecosystem is composed of animals, plants, and environment. Therefore, its development will be disturbed by some factors. In order to maintain the biodiversity and make the strategies of management practices, it is the essential to discuss the various degrees of these influential factors. This study selected the Nanjenshan Ecological Reserve as the study site. Digital photogrammetry, geographic information system (GIS), landscape ecological indices and Markov chain model are used to explore the forest dynamics, to simulate the vegetation succession, and to discuss the interferences. At last, this study also proposed some advices of management strategies for the Kenting Nation Park.
In this study, the vegetation coverage of the Nanjenshan Ecological Reserve was decided by references and survey data. Landscape types were interpreted on aerial photo data of 1976, 1989, and 1997 respectively. By the results, we found that the area of forest site is one of the biggest in the Nanjenshan Ecological Reserve and they are effective to achieve a stable high-density forest vegetation society, and the ecosystem itself is dynamic in sequential times series.
Furthermore, the equilibrium matrix of Markov chain model is used to estimate the tendency of forest vegetation dynamics over time interval of 1989 and 1997. We found that the ecosystem is steady.
There are many disturbing factors in dynamic ecosystem and after knowing where and how they affect the vegetation succession we get some important conclusions on the management practices. In this study, the transitional probability matrix and the mean patch fractal dimension index are discussed as the different disturbing factors of the Nanjenshan Ecological Reserve. Results of this study showed that the moisture, northeastern monsoon, road establishment, afforestation, and human exploitation are these disturbing factors for vegetation society as a whole. Due to the various degree of proper adaptive management strategies for each disturbing factor accordingly.
In this research, the landscape ecology theory, stochastic model, environmental influence, and management strategy are used to study the vegetation dynamics of the Nanjenshan Ecological Reserve. The results proved that establishment of the Nanjenshan Ecological Reserve is functional.
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