北大武山區植群多樣性之研究

Study on Vegetation Diversity of Peitawushan

葉慶龍(Ching-Long Yeh) ； 廖家宏(Jia-Hong Liao)

《國立臺灣大學生物資源暨農學院實驗林研究報告》 21卷2期 (2007/06) Pp. 117-132

https://doi.org/10.6542/EFNTU.200706_21(2).0003

摘要

本研究旨在探討北大武山區之植群多樣性隨海拔梯度與南北坡向之植物多樣性變化，共設置35個0.05 ha樣區，觀測8項環境因子。共計598種維管束植物，28種稀有植物。經雙向指標種分析與降趨對應分析得出3植群型與4亞型，分別為厚葉柃木－臺灣鐵杉型(Eurya glaberrima-Tsuga chinensis var. formosana type)；假長葉楠－長葉木薑子型(Machilus japonica-Litsea acuminata type)，此型再分無脈木犀－假長葉楠亞型(Osmanthus enervis- Machilus japonica subtype)、臺灣杜鵑亞型(Rhododendron formosanum subtype)、瓊楠－猪腳楠亞型(Beilschmiedia erythrophloia-Machilus thunbergii subtype)與臺灣厚距花－阿里山千金榆亞型(Pachycentria formosana- Carpinus kawakamii subtype)及黃肉樹－燈稱花型(Litsea hypophaea-Ilex asprella type)。以典型對應分析探討植物社會與環境因子之相關性，其中以海拔、地形位置、坡度、含石率與冠層覆蓋度為主要影響植物社會變化之因子。各植群型之α多樣性以黃肉樹－燈稱花型為最高。南向樣帶草本植物在各海拔佔最高的比例，而北向樣帶各植物生活型之變化則大於南向樣帶；在β多樣性上，南向樣帶之物種轉換率與海拔梯度相關，木本植物平均95%物種轉換需967 m，草本之轉換率與木本有相同的趨勢，在海拔1,359-1,457 m 有較快速的物種轉換；而北向樣帶則與海拔梯度無密切相關，木本與草本之轉換率在1,560-1,650 m 及1,650-1,740 m 之間物種有較快的轉換率。

關鍵字

雙向指標種分析 ； 降趨對應分析 ； 典型對應分析 ； α多樣性 ； β多樣性 ； 物種轉換率

並列摘要

The objective of this study were to investigate the vegetation diversity along altitudinal gradient and plants diversity pattern along the northern/southern transects of Peitawushan. 35 plots of 0.05 ha were established and 8 environmental factors were monitored. There were 598 species of vascular plants, with 28 rare plants. Three vegetation types and four subtypes were identified by using DCA and TWINSPAN. The first vegetation type was Eurya glaberrima-Tsuga chinensis var. formosana type. The second vegetation type was Machilus japonica-Litsea acuminata type, which could be further divided into Osmanthus enervis-Machilus japonica subtype, Rhododendron formosanum subtype, Beilschmiedia erythrophloia-Machilus thunbergii subtype, and Pachycentria formosana-Carpinus kawakamii subtype. The third vegetation type was Litsea hypophaea-Ilex asprella type. CCA indicated that altitude, topographic position, slope, stone content in the soil and coverage of canopy made significant contribution to the variation of vegetation composition. For woody and herbaceous species, the Litsea hypophaea-Ilex asprell type had the highest alpha diversity values. In terms of habit, the proportion of herbaceous plants in the southern transect was generally higher than that of the northern transect at the corresponding altitude. For the beta diversity, the 95% turnover range for the woody species in the southern transect was calculated as 967 m. Both woody and herbaceous species showed the highest turnover ratios at elevation 1,359-1,457 m. For the northern transect, the change in species composition with altitude was less significant. The higher turnover ratios of woody species and herbaceous species were observed at elevations 1,560-1,650 m and 1,650-1,740 m, respectively.

並列關鍵字

TWINSPAN ； DCA ； CCA ； Alpha diversity ； Beta diversity ； Plants turnover ratio