高屏溪流域崩塌地之植生復育分析

Analyzing the Vegetation Restoration of Landslides in the Gaoping River Basin

因莫拉克颱風重創南臺灣，尤以高屏溪流域更是受創嚴重，故本研究主要針對高屏溪上游之崩塌地設置樣區，以瞭解崩塌地之植生復育情形。研究結果得知，多數崩塌地仍屬於擴崩型或新增型，而崩塌地須就不同情況加以規劃合適方案，以小集水區治理為原則。又所調查之半數以上施業地的之土壤硬度屬根系生長良好、種子發芽的範圍內。另研究區內常用為撒播之木本植物中，以臺灣白蠟樹、苦楝較為適合；而草本植物種子則於多數施業地處之生長情況亦佳，其中以百喜草—山黃麻型之地被層均勻度高於類地毯草—羅氏鹽膚木型，且其演替速度亦較快。此外，因九芎、薄姜木、破布子等萌櫱良好，建議亦可作為編柵的木樁，以確保並加速復育成效。並建議對小花蔓澤蘭等外來種族群之拓殖情形加以密切監測。綜合言之，區內自然植生復育情況多較人工植生復育情況為佳；然因藉由人工播種及坡面處理後，能增加其生物多樣性，並可加速演替之速度，助其復原至自然的生態面貌。 Typhoon Morakot seriously wrecked southern Taiwan, especially upstream Gaoping River. This study set sample plots on the landslides in Gaoping River basin to realize the vegetation restoration. From the results of investigation, the vegetation types of understory on landsliding areas could be classifi ed into expanding type and adding type. The landslide management should be planned on a case by case basis, and using small catchment as foundation. In the meanwhile, the soil characters of more than a half of the managed plots investigated were suitable for root growth and seed germination. Among the common sowing woody species, Fraxinus griffi thii and Melia azedarach grew better. Herb seeds developed well in the most managed plots. In the distribution evenness of the understory, Paspalum notatum-Trema orientalis type was higher than Axonopus affi nis-Rhus javanica var. roxburghiana type. The former type recovered faster, too. As Lagerstroemia subcostata, Vitex quinata, and Cordia dichotoma sprout easily, they are better choices for sowing and helpful for the quick recovery. On the other hand, the monitoring the exotic species expansion, such as Mikania micrantha is recommended. In conclusion, the natural restoration was more effective than the artificial recovery in the research area. However artificial sowing and slope surface processing will enhance biodiversity and succession speed, and is helpful for back to original natural vegetation.