台灣北部福山試驗林永久樣區之植物社會分類及梯度分析

Vegetation Classification and Ordination of a Permanent Plot in the Fushan Experimental Forest, Northern Taiwan

王相華(Hsiang-Hua Wang) ； 潘富俊(Fuh-Jiunn Pan) ； 劉景國(Chin-Kuo Liu) ； 于幼新(Yu-Hsin Yu) ； 洪聖峰(Sheng-Feng Hung)

《台灣林業科學》 15卷3期 (2000/09) Pp. 411-428

https://doi.org/10.7075/TJFS.200009.0411

摘要

於哈盆溪中上游，福山試驗林2號試驗集水區量水堰上方100m處，設置長200m、寬70m的1.4ha植物社會永久樣區，樣區長軸為南－北走向，跨越溪谷、下坡、中坡、上坡及稜線等不同地形：短軸為東西走向，大致與等高線平行。將1.4ha永久樣區約略沿等高線劃分為20個70×10m長條型分析樣區，進行植物社會分類及分布序列分析，樣區內調查胸徑≧1cm的木本植物之胸徑。
永久樣區是以樟科、殼斗科及茶科佔優勢之植物社會。雙向指標種分析結果，永久樣區可區分為稜線－上坡型、中－下坡型及溪谷型3種生育地型植物社會。稜線－上坡型植物社會之特徵種是大明橘、圓葉冬青、小花鼠刺、小葉赤楠、烏來冬青、西施花，以及厚皮香。溪谷型植物社會之特徵種是紫珠、裹白蔥木、長梗紫麻及赤皮。中－下坡型生育地具有推移帶植物社會的組成特徵，特徵種的分化較不明顯，冇樟是唯一可判識的特徵種。稜線一上坡型社會有較高的物種豐富度、物種歧異度、胸高斷面積及密度，並沿著稜線往溪谷的方向逐漸遞減。
梯度分析結果指出，海拔高度、有效土壤深度及平均樹冠層高度是影響植物組成及結構分化之主要環境因子，均以稜線－上坡型生育地為最高，溪谷型植物社會最低。中－下坡型生育地的坡度，明顯高於其他兩個生育地型。調查結果顯示，地形位置影響土壤干擾的強度，是造成多項環境因子及植物組成呈現梯度變化的主要原因。上述3種生育地型植物社會在結構及組成等定量特徵上有顯著的差異。

關鍵字

地形 ； 土壤干擾 ； 植物社會分類 ； 梯度分析 ； 福山試驗林

並列摘要

A 1.4-ha permanent plot (200×70 m) was set up in the no. 2 watershed of the Fushan Experimental Forest, northern Taiwan. Over an elevation range of 690-820 m, the long axis of the permanent plot crosses several different topographic units, which are ridge, upper slope, middle slope, low slope, and valley, while the short axis of the permanent plot nearly parallels the contour. This permanent plot was divided into twenty 70×10 m units (stands) for vegetation classification and ordination analysis. All woody species with a dbh ≧1 cm were recorded.
The families of Lauraceae, Fagaceae, and Theaceae dominated this area. Three habitat types were derived based on the results of TWINSPAN analysis. They were ridge-upper slope habitat type (RU type), middle-low slope habitat type (ML type), and valley habitat type (V type). The characteristic species of the RU type were Myrsine sequinii, Ilex goshiensis, Itea parviflora, Syzygium buxifolium, flex uraiensis, Rhododendron ellipticum, and Ternstroemia gymnanthera; the characteristic species of the V type were Callicarpa dichotoma, Aralia bipinnata, Villebrunea pedunculata, and Cyclobalanopsis gilva. The species composition of the ML type characterizes the ecotone between the RU and V types, and Cinnamomum micranthum was the only characteristic species. Species richness, species diversity, basal area, and density were highest in the RU type, and decreased downslope gradually toward the ML and V type habitats.
The results of ordination indicated that elevation, effective soil depth, and mean canopy height correlated to axis 1 of DCA (detrednded correspondence analysis). The RU type had the greatest elevation, effective soil depth, and mean canopy height. In contrast, the V type had the lowest elevation, effective soil depth, and mean canopy height. The slope was greater in the ML type area. Topography was significantly correlated with soil disturbance, which induced differentiation of micro-environmental factors and species compositions. The result also revealed that the 3 habitat types significantly differ in species composition and several quantitative parameters.

並列關鍵字

topography ； soil disturbance ； vegetation classification ； ordination ； Fushan Experimental Forest