Assessing Landscape Changes in the Liukuei Ecosystem Management Area Using Markov Models

應用馬可夫模式探討六龜生態系經營區之地景變遷

許立達(Li-Ta Hsu) ； 鄭祈全(Chi-Chuan Cheng)

《台灣林業科學》 15卷1期 (2000/03) Pp. 41-49

https://doi.org/10.7075/TJFS.200003.0041

摘要

地景變遷的偵測與監測乃是地景生態學及生態系經營的重要一環。本研究以1988年及1996年之航空照片數化六龜生態系經營區的土地覆蓋圖，以比較兩期間土地覆蓋之變化，並應用馬可夫模式分析地景過去之變遷及預測未來假想之土地覆蓋情況。過去地景之變遷顯示人工造林顯著地改變了當地之地景，然而天然林亦取代了許多人工林。所有的伐木跡地不是被人工造林，便是已回復為天然林，反之，無立木地的植生恢復情形則較差，顯示崩塌地或裸露地對地景的影響比伐木更為持久。崩塌地或裸露地則較常見於針葉樹造林地。為探討地景變遷之長期趨勢，本研究以模擬來推估未來假想之地景狀態。假設以後將停止所有人為干擾，而且變遷機率一直維持不變，長期模擬的結果顯示除非持續人工造林，否則天然林終將取代所有的人工林。

關鍵字

地景變遷 ； 馬可夫模式

並列摘要

Detecting and monitoring landscape changes are important issues of landscape ecology and ecosystem management. This study used 2 sets of aerial photographs taken in 1988 and 1996 to derive land cover maps of the Liukuei ecosystem management area. The 2 maps were compared to identify transitions among land cover types. Markov models were used to examine historical changes of the landscape, and to project hypothetical future land cover distributions. The historical changes show that afforestation significantly altered the landscape, but natural forests also extensively reclaimed man-made plantations. All cut areas were either replanted or reclaimed by natural forests. In contrast, vegetation recovery on nonforested lands was less successful, suggesting that landslides or bare lands might have a longer-lasting effect on the landscape than harvesting would. Landslides and bare lands appeared to be more likely to occur on conifer plantations. To assess the long-term trends of landscape changes, a simulation scenario was developed to hypothetically project future landscape conditions. The scenario assumed that all human disturbances would cease. Results of the simulation show that, under the assumption of stationary transition probabilities, natural forests would eventually reclaim all man-made plantations unless reforestation continues.

並列關鍵字

landscape change ； Markov model