浙江西天目山天然林及银杏种群考察报告

在完成国内多处同类型研究的基础上 ,笔者对西天目山双清溪沟谷天然林及其银杏进行了专题考察 ,所获第一手资料包括 :双清溪森林古道样带式路线考察立木分布平面图 ;天目山双清溪天然林中银杏及伴生树种调查总表 ;双清溪天然林中银杏种群调查明细表 ;“5代同堂银杏”的树木形态学调查研究 ;禅源寺古森林群落的成分、结构及性质考察等。在充分分析的基础上作者认为 ,双清溪天然林原应属於典型“落叶与常绿阔叶混交林”群落 ,现已进入“针阔叶、落叶与常绿阔叶混交林”演替阶段。该演替系人为干扰下的一种“偏途演替”。银杏种群参与了演替和历史发展的全过程 ,因此 ,它们应该是野生的。“5代同堂银杏”建议正名为“无性系多代同株银杏”比较恰当。禅源寺古森林群落是双清溪沟谷天然林的延伸和残余部分 ,可简称为“禅源寺古森林残存群落”。

A report on the natural forest with Ginkgo population in west Tianmu moutains,Zhejiang province

Based on the same sort of studies in various parts of China,a specific survey was conducted on the natural forest with Ginkgo biloba population located at Shuangqingxi of the west Tianmu Mountains,Zhejiang province.The firsthand materials contain a plane figure of the standing trees in the sample plot along a valley with an ancient path, a general list of the trees including the accompanying species, the detailed table of Ginkgo biloba population, a morphologic investigation of "five generation living together" Ginkgo biloba and a study of the structure,component and nature of the ancient community around Chanyuan temple.In the light of the analysis, the authors hold that Shuangqingxi forest is a typical mixed one, composed of decidaus and evergreen broad leaved specices,but now leading to the stage of mixed coniferous,decidaus and evergreen broad leaved forest.It is in fact a deflected reccession influenced by human beings. Ginkgo population is the important component of the forest and goes through the whole succession course of the community.So it should be wild,and authors suggest that the so called "five generation living together" Ginkgo biloba should be renamed as "asexual multi genrations in one body",which could develop only in the condition of old forest community.