摘要或動機

When one time we beautified our campus. It made us meet the snails, Euphaedusa sheridani shihi Chang, unexpectedly. Maybe snails make people associate with the holes on vegetables tops in thinking. Do all of the snails make vegetables tops as their food? We compared with the weight of the wood which has been stayed by snails or not. After a week, the weight of the wood which has been stayed by E. sheridani shihi Chang decreased obviously. It showed they also make wood as their food. What do they decompose wood become? First, we used the basic Carbohydrate's detection means to test the eluate of the wood which has been stayed by E. sheridani shihi Chang. However, we found both the eluate of the wood which has been stayed by E. sheridani shihi Chang or not can examine the Pentose out. So next, we plan to use SDS-PAGE to analyze the left enzyme on the wood, and use it to prove whether they secrete enzyme in mouth to decomposed wood or not. In addition, the holes these snails made and the environment are connected. By means of changing light, temperature and humidity to experiment with how much wood can these snails decompose. We found in the dark, about 20℃ and moist environment, they could decompose the wood the most. Finally, the holes they made on the wood also have its ecological niche. They decomposed the wood not only hastened the dissolution of the wood, but also provided the microhabitat for alga, fungi and small bugs.一次綠化校園的活動，製造了我們與石氏煙管蝸牛的邂逅。蝸牛，或許使很多人想到蔬菜上的洞，但真的所有的蝸牛都以蔬菜為食嗎？比對有無蝸牛棲息的兩組木頭，結果一星期之後有蝸牛棲息的木頭重量明顯減少，顯示蝸牛也以木頭為食。那麼牠們把木頭分解成什麼呢？我們先以基本的醣類檢測方法，檢測蝸牛棲息過的木頭表面洗出液，不過發現不管有無蝸牛棲息皆可檢驗出五碳醣，接著預計用SDS 膠體電泳看是否可以分離分析出蝸牛在消化木頭時殘留在木頭上的酵素，以證明蝸牛是否在口腔分泌酵素以分解木頭。至於環境和蝸牛消化木頭的關係，我們藉著改變光線、溫度、溼度等變因進行實驗，發現牠們在陰暗、潮濕、約20℃的環境下可以分解最多的木頭。最後，牠們分解木頭形成的洞也具有其生態意義，不僅加速木頭的分解，也製造了微棲地提供藻類、真菌及小型生物的生存空間。