應用無線網路感測技術於紅樹林環境中招潮蟹數量之研究

Using a Wireless Sensor Network Technology to Investigate the Fiddler Crab Population in Relation to Environmental Conditions in Mangrove

紅樹林為熱帶及亞熱帶海岸地區最特殊且重要的濕地生態系，故其棲地與指標物種監測有其必要性。本研究利用無線感測系統，收集淡水河紅樹林自然保留區之微氣候環境資料與招潮蟹數量之影像，探討潮汐時間、季節差異、溫濕度變化與招潮蟹數量之關係。研究結果顯示，招潮蟹出現數量與溫度（相關係數為0.407, p < 0.01）呈正相關，而與濕度（相關係數為-0.376, p < 0.05）及潮汐（相關係數為-0.563, p < 0.01）呈現負相關。此外招潮蟹數量於季節間有顯著差異（F0 = 16.551），其中夏季出現之數量明顯多於秋、冬季間，這表示招潮蟹於濕度較低、溫度略高之環境下的活動力較強。無線網路感測技術確實能提供紅樹林地區與其物種的長期環境監測資料，可作為生態資源保育之參考。

Mangrove is the most unique and important wetland ecosystem of the tropic and subtropic coastal forests. It is imperative to monitor its environmental conditions and index species. We used a wireless sensor network system to determine the relationships between the fiddler crab population and environmental variables, humidity, temperature, tidal levels, and seasons, at the Danshuei River Mangrove Nature Reserve in Taiwan. The results showed that the crab population was positively correlated with temperature (r=0.407, p＜0.01) but negatively with humidity (r=-0.376, p＜0.05) and tidal level (r=-0.563, p＜0.01). Also the population changed significantly with seasons (F0=16.551); the population was larger in summer than in autumn and winter. In other words, the crabs were more active at low humidity and higher temperature. This wireless sensor network system was recommended as a long term monitoring system of coastal mangrove wetland habitat and the index species for the conservation purpose.