嘉義樹木園肯氏南洋杉及巴西橡膠樹生育環境與風險評估研究

本研究目的在瞭解植物園都市森林區內活動民眾踩踏土壤對局部林地土壤產生硬實之影響。就嘉義樹木園肯氏南洋杉及巴西橡膠樹展示區內，經土壤硬化測定後劃分為土壤硬實區與非硬實區。結果顯示土壤硬實造成肯氏南洋杉、巴西橡膠樹就生物學上根系數量減少、年平均生長量降低、樹冠面積漸少；力學上木材彎曲強度、角度降低及生物力學上，樹木生長活力下降，導致無法形成根冠幾何形狀，大幅增加樹木枯死、崩壞及樹幹折斷的可能性。透過目視樹木評估法（VTA）評估結果，依據樹木之衰退度及樹木健全度兩項指標均顯示出非硬化區的肯氏南洋杉及巴西橡膠樹有較佳的活力與健全度。
本資料集內容與資料為林業試驗所108年「永續林業生產試驗研究」科技計畫項下之「都市林管理與應用」結案工作項目所執行之成果。
This study aims at understanding how people’s activities in the urban forest area botanical garden influence the degree of soil compaction on the partial land. At the display area of Araucaria cunninghamii and Hevea brasiliensis in Chiayi Arboretum, soil-hardening measure is used and this area is divided into hardening section and its contrastive section. The result shows as follows: biologically, soil hardening leads to a reducing number in root system of Araucaria cunninghamii and Hevea brasiliensis, a lower level in annual average growth, and canopy area reduction; mechanically, wood bending strength and angle decrease and in biological mechanics, tree growth vitality falls so that it is unable to form root crown geometry, and hence it adds possibility of tree death, collapse and broken trunk. Through tree visual assessment (VTA), the two indicators of tree decay and tree health assessment show Araucaria cunninghamii and Hevea brasiliensis at the contrastive section exhibit better vitality and health.