| 摘要: | 本研究以植群調查方式探討金門海岸地區清雷後的外來種植物蔓延情形，並以田野現地實驗方式探討物理性防治對於外來種防治的成效。樣區的設置，依據不同的海岸類型，分別在金門本島的沙崗、后扁及烈嶼鄉的將軍堡，設置3個45×50公尺大小的永久樣區。於樣區中隨機設置外來種物理防治實驗，包括(一)不拔除(二)每季拔除一次(三)每年拔除一次等三種處理隨機排列重複3次。植群調查於實驗設置前後每季進行。調查是以1×1公尺樣框內的10×10網格計算每個物種的覆蓋面積，並加以分析。
一般而言，除雷後的植生復原情況良好，裸露地面積逐年減少。其中原生種植物覆蓋面積大於外來種植物覆蓋面積。物理防治實驗則發現每季移除明顯地抑制外來植物，使原生植物面積逐漸增加，但是每年移除之效果則不顯著。除物理防治外，裸露程度、物種特性、優勢物種變化與氣候條件等也都會影響結果。例如：原生種如為具走莖之禾本科植物時，其佔領外來種移除後裸露地之情況較良好，但移除面積較大時，外來種回復之情況較明顯。優勢物種大量落葉而使得原生植物面積容易受影響。秋季特殊的乾旱條件可能會選擇性的干擾外來種，有利於原生種的復原，但本研究執行時間有限，對於乾旱是否有助於外來種的防治，尚需更長期的觀察資料方能證實。
在外來植物的防治上，建議國家公園等保育單位可於生態敏感度高、具稀有植物等重點地區應用物理防治，並於每季拔除外來植物且妥善處置，特別是與原生種呈現負相關的外來種，為潛在的強勢植物，應於這些外來植物開花結果前進行移除，以減低外來種對原生植物的危害。
The vegetation survey was made on coastal areas of Kin Men Islands to study vegetation restoration and exotic plant invasion after landmine removal. Experimental removal of exotic plants using mechanical control to observe effect of exotic plant. Three permanent plots of 45×50 m2 were set in Jiang Jun Bao, Sha Gang and Hou Bian to obtain vegetation succession data. Three treatments of controlling exotic plant species (1) Control (2) remove exotic plant each year (3) remove exotic plant each season. Complete random block was adapted in 3 replications. Plant species and their dominance were recorded by 1×1 m2 subplot bases within the permanent plots.
Vegetation restored well and bare ground reduced in general. Native plants cover area was more than exotic plants. The result indicated that removal of exotic species every season enabled the expanding of native species. The result of remove exotic plant each year was non significant. In addition to mechanical control, area of bare ground, species characteristic, dominant species changing and condition of climate also affected the result. For instance, when the native plants of Poaceae have stolon, it will establish in bare ground on which the exotic plants was removed. But if bare ground is more that exotic plants would restore. Characteristic species leaves drop may affect native plants area changing. Unusually dry autumn may selective interference alien plants and restore native plants. The study of time is not enough to check drought effect of exotic plants control and need to observe for a long time.
In the prevention and control of exotic plants, it is recommended that physical control methods i.e. removal of exotic plants on a quarterly basis should be used in the high ecological sensitivity areas and process properly, especially in the areas that native species was negatively correlated with them. The competitive alien plants should be removed before flowering and fruiting. |
