| Summary: | 碩士 === 國立臺灣大學 === 生物環境系統工程學研究所 === 103 === Urban sprawl causes habitat loss and the conversion of natural landscapes to residential, business, and industrial areas. Recently, efforts have been put in place to create environments for wildlife in urban areas to achieve sustainable development. Amphibians were selected as target species in this study to evaluate the effectiveness of the habitat creation in the urban area. Anurans are common species in Taiwan and sensitive to the changes of environment conditions due to their physiology and life history. Field surveys were conducted at five natural wetlands, three constructed ecological ditches, and two drainage ditches within Yong-Jian Ecological Park, Wenshan District, Taipei City. Collected data included richness of frogs, water quality, microclimate and microhabitat of the ten wetlands. A multiple regression method and corrected Akaike information criterion (AICc) were used to analyze the data by two approaches.
First, the relationship between the average frog (Fejervarya limnocharis) number and the average environmental parameters (April 2014 to January 2015) were analyzed to provide a general perspective. Dissolved oxygen (1.95 to 5.14 mg/L) and relative humidity (75 to 83%) are positively correlated to the average frog number whereas maximum air temperature (28.57 to 38.14 °C) is negatively. Second, the data from April 2014 to November 2014 (eight months) were calculated on monthly basis. The used parameters in the eight multiple regression models were all different from each other. However, tree canopy, grass coverage, pond surface area, dissolved oxygen, and bicarbonate ion are positively correlated with the number of the Fejervarya limnocharis. However, the occurrence of the Fejervarya limnocharis was negatively related to bank slope and nitrate concentration. According to this study, the number of the Fejervarya limnocharis was higher at the constructed ecological ditches sites with following attributes: tree canopy > 80%, water surface > 50 m2, bank slope < 20°, Nitrate concentration < 0.1 mg/L, hydrogen carbonate ion > 200 mg/L.
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