崩塌地既存樹木保留之群落拓展研究

Vegetation Development on Landslide Area: The Fertility Effect of Existing Tree Island

林信輝(Shin-Hwei Lin) ； 蘇郁婷(Yu-Ting Su)

《造園景觀學報》 19卷3期 (2013/09) Pp. 1-13

摘要

本研究為探討崩塌地保留既存樹木對於孔隙森林化之影響。除調查林木擴展情形與外來草種影響外，並以原保留三株既存樹木之蘇樂野溪崩塌地區塊作為研究範圍，探討植群拓展機制；現地因羅滋草強勢生長，唯有保留木周邊形成一縱軸40M、橫軸30M的樹林群落；研究中利用各年代綜合優勢度指數(Summed Dominance Ratio)比較當地族群變化；使用ArcGIS進行正射影像圖分析其擴張趨勢；藉由現地調查得知，該區塊共18種樹種，依現地森林群落分布調查、土壤潛在種子分析等綜合判斷，樹林群落之拓展機制應包括母樹林天然下種、生長基地之微氣候改變效應及鳥獸間接促進種子入侵生長有關。崩塌地保留既存樹木可發展成樹島，加速演替速率及森林化歷程達到植生復育成果。

關鍵字

樹島效應 ； 植生演替 ； 崩塌地

並列摘要

This study investigated the fertility effect of retained trees for vegetation development on landslide area. The summed dominance ratio (SDR) and imagery analysis on the ortho-images were indexed to represent the trend of vegetation recovery. In addition, this study examined the mechanism of vegetation development using comprehensive evaluation including forest community distribution and soil seed bank analysis. The findings indicated that the principle mechanisms of vegetation expanding on landslide area included the natural seeding from parent stand, plant sprouting, the effect of micro-climate change, and wildlife seeding. Moreover, reserving the survived trees in landslide area can accelerate the succession speed into forestation and support vegetation restoration in landslide area.

並列關鍵字

tree island effect ； vegetation succession ； landslide area