桉树人工混交林下植物多样性特征

Characteristics of Understory Plant Diversity in Artificial Mixed Eucalyptus Forests

[目的]了解紫金县黄砂林场不同桉树人工混交林下植物组成与多样性特征。[方法]选取桉树-香樟混交林(Ⅰ)、桉树-杉木混交林(Ⅱ)和桉树-马尾松混交林(Ⅲ)3种桉树人工混交林为研究对象,探讨桉树人工林树种组成与林下植物多样性的关系。[结果]3种人工林下植物共有35科50属51种,其中,灌木植物15科19属20种,以粗叶悬钩子、杜茎山和野牡丹为主;草本植物15科24属24种,以芒萁、山菅、乌毛蕨和金星蕨居多;藤本植物6科7属7种,以葛藤、海金沙和清风藤分布较广。灌木层、草本层和藤本植物层物种Simpson优势度指数和Shannon多样性指数均表现为桉树-香樟混交林(Ⅰ)最大,桉树-马尾松混交林(Ⅲ)最小。3种桉树人工林Simpson优势度指数(D)、Shannon多样性指数(H)均表现为草本层>灌木层>藤本植物层。[结论]营造桉树-香樟混交林更有利于促进林分生长,提高林下植物多样性,在制订提高桉树林分质量措施时,要重视经营措施下人工林下植物多样性与树种组成间的关系。

[Objective]To understand the composition and diversity characteristics of understory plants in different artificial mixed Eucalyptus forests at Huangsha Forest Farm in Zijin County.[Method]Three types of Eucalyptus artificial mixed forests,namely Eucalyptus camphor mixed forest(Ⅰ),Eucalyptus fir mixed forest(Ⅱ),and Eucalyptus masson pine mixed forest(Ⅲ),were selected as the research objects to explore the relationship between tree species composition and understory plant diversity in Eucalyptus artificial forests.[Result]The results showed that there were a total of 51 species of 35 families,50 genera,and 15 families,19 genera,and 20 species of shrubs in the understory of the three artificial forests,with the main species being Rubus alceifolius,Maesa japonica,Melastoma candidum;there are 24 species of herbaceous plants in 24 genera and 15 families,with the majority being Dicranopteris dichotoma,Melastoma candidum,Blechnum orientale and Arathelypteris glanduligera;there are 7 species,7 genera,and 6 families of vine plants,with Pueraria montana,Lygodium japonicum and Sabia japonica being more widely distributed.The Simpson dominance index and Shannon diversity index of species in the shrub layer,herbaceous layer,and vine layer are all highest in the Eucalyptus-Cinnamomum camphora mixed forest(Ⅰ) and lowest in the Eucalyptus-Pinus massoniana mixed forest(Ⅲ).[Conclusion]Creating a mixed Eucalyptus-Cinnamomum camphora forest is more conducive to promoting stand growth and improving understory plant diversity.When formulating measures to improve the quality of Eucalyptus stands,attention should be paid to the relationship between understory plant diversity and tree species composition in artificial forests under management measures.