- 期刊
- OpenAccess
原生闊葉樹種在六龜瘠劣地的栽植表現
Planting Performance of Natural Hardwood Species on a Degraded Site in the Liukuei Area
摘要
位於台灣西南部的六龜地區，因乾旱季節較長及部分林地土層淺薄的關係，形成復舊造林不易成功的瘠劣地。本試驗選擇9種原生樹種造林，由各樹種長期的生長與成活表現來檢討其適應能力。另外並對試區內早期的復舊造林木及天然更新之原生樹種的種類及數量等進行調查，作為決定該地區不良生育地造林樹種選擇之參考。9種原生樹種造林後1、2及7年生的成活率皆以光臘樹為最高，赤楊及牛樟則無法適應。在排除可能來自苗木品質不良及造林技術不佳等因素後，7年生造林木的適應能力以相思樹的表現為最優，有最大的樹高及胸徑，光臘樹次之。相思樹在13m以下的分叉比例低於光臘樹。早期的復舊造林樹種以樟樹的生長表現較優。造林地自然發生之原生樹種達23種，包含大喬木類的樟科及殼斗科等主要樹種，並以該地區的優勢種台灣栲的株數為最多。原生樹種的發生可增加林地的生物歧異度。試區單位面積內共有木本植物32種，1,195/ha，因此存在於伐木跡地上的幼苗庫及種子庫等天然造林材料應予加以重視。
並列摘要
Nine native hardwood species were enrichment planted in the Liukuei area, located in southern Taiwan, where there was a degraded site, considered to be difficult to reforestate because of shallow soils and long periods of dry weather in the fall and winter. The performance of growth and survival for these 9 species, and the occurrence and amounts of other tree species in this site including previous reforestated trees and naturally regenerating native trees, were investigated. Fraxinus formosana had the best seedling survival rate after planting for 1, 2, and 7 yr, while Alnus formosana and Cinnamomum kanehirae failed to survive. According to sapling survival, excluding poor seedling quality and silviculture practices, Acacia confusa had the best adaptability and the greatest height and DBH growth, while F. formosana was the second. Moreover, the branching rate on the trunk below 1.3 m high of A. confusa was less than that of F. formosana. Among the previously reforestated tree species, the growth of C. camphora was better than that of other species. There were 23 tree species which naturally regenerated on the plantation, of which the Lauraceae and Fagaceae constituted the major tree species. The amount of Castanopsis formosana, a dominant species in this area, was the greatest. The biodiversity of this plantation at 32 species and 1,195 individuals/ha thus increased, indicating that it is very important to investigate the potential banks of regeneration seedlings and seeds of native species originating from the disturbed land.