The effect of environmental factors and adjacent land use of wetland on crab community in mid-Taiwan

• Main Authors: LIN, WEI-CHI, 林韋齊
• Other Authors: LIN, HUI-CHEN
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/62582228376049791544

碩士 === 東海大學 === 生命科學系 === 104 === The biodiversity of estuarine wetlands was affected by natural process and human disturbance, such as seawall construction, pollution, and tidal effect. Many kinds of data were used to be indicators for quantifying the quality of wetland, including water quality, the biodiversity or composition of birds, fishes, invertebrates, or condition of coastline. Among the biodiversity indices, Abundance Biomass Comparison Method (ABC method) is used to detect the effect of environmental stress on marine macro benthic communities and was widely used on fish or benthic community in recent years. ABC method was applied to one of the previous study in our lab in 2003 and, in that study, the crab communities in Da’an, Gaomei, and Dadu wetlands were all under moderately stressed. But the environmental factors were not included in the discussion of that study. Therefore, the first part of this study was to exam the association between environmental factors and crab community. The second part of this study is to assess the environmental stress on the three wetlands in ten years through analyzing the difference of crab community in different year. Biotope Area Factor (BAF) was widely used in landscape ecology. In BAF, it is hypothesized that different land uses were weighed by the permeability and vegetation cover ratio. When the surface has a higher permeability or more vegetation covered, a higher ecologically-effective weighting will be given. Therefore, BAF may be applied to assess the level of human development near wetlands. But there were no ecological data available for supporting the ecologically-effective part and the linkage between BAF and biodiversity was not known. The third part of this study was to test whether the BAF value correlated with species diversity of wetlands. I used ABC method to study crab composition of the four wetlands in central Taiwan and collected soil samples to analyze soil content. The adjacent land use in four wetlands was included to obtain BAF value and crab community was to obtain Shannon-Wiener index and Simpson indices. Results indicated that crab community was affected by soil organic content, soil water content, soil particle size, soil pH, and habitat types. From my study in 2013, the crab community in Gaomei wetland was under higher environmental stress than that in 2003, and the composition of crab communities in 2003 and 2013 were different. It could result from the human disturbance on Gaomei wetland. There was no correlation between BAF and biodiversity indices (Shannon-Wiener and Simpson indices), but crab community was significantly different in different types of adjacent land use. The environment of wetland may be affected by adjacent land use and crab community may be indirectly affected by adjacent land use.