中国东南部丹霞地貌区小尺度植被分异结构研究

陡崖坡广泛发育是丹霞地貌的基本形态特征。典型的丹霞地貌山块往往四面陡崖,山块之间也因此形成被陡崖围合的沟谷。特殊的地貌造就了许多特殊的小生境,产生了特殊的植被分异现象。本文梳理了山地自然分异和丹霞地貌生态与植被分异方面的研究文献,发现人们对于丹霞地貌区小尺度植被分异的关注不足。为此,针对丹霞地貌区小尺度植被分异这个最具有个性化的自然分异现象与本质进行了初步探讨,得到主要结论：丹霞地貌区小尺度的自然生态分异不符合一般意义上山地自然带分异规律,其根本原因在于地貌所引起的生境差异;丹霞地貌区的山顶效应实质上是“干岛”效应,其沟谷效应实质上是一种“热岛+湿岛”效应;孤立山顶的边缘形成生态结构“突变带”,使得山顶形成孤立的“环状生态圈层”;因地貌差异形成的小生境差异,决定了丹霞地貌区的植被分异图谱。这种小尺度植被分异研究能够丰富中国山地科学研究,并为丹霞地貌区植被生态环境保护提供一定的参考。

Small Scale Vegetation Differentiation Structure in Danxia Landforms,Southeast China

The widely existing cliffs is the basic morphological feature of Danxia landform. The typical Danxia landform are usually surrounded by steep cliffs, and due to the surrounded cliffs ravines are formed between mountain blocks. Special landforms have created many special habitats and special vegetation differentiation. In this paper, by reviewing previous studies on the ecological and vegetation diversity of Danxia landform, we found that the differences of small scale vegetation in Danxia landform area was not given enough attentions. To this end, this article makes a preliminary discussion on the most individualized natural differentiation and essence of the small scale vegetation differentiation in Danxia landform area, and the main conclusions are as follows: the small scale natural ecology differentiation of the Danxia landform area is not in conformity with the general sense of natural law, with its basic reason of differentiation habitat differences are caused by its special landscape; The peak effect and ravine effect of Danxia landform area are essentially the "dry island" effect and "hot island + wet island" effect, respectively; An ecological structure "mutated belt" is formed on the edge of the isolated mountaintop, which makes the mountain top an isolated "circular ecological ring". The vegetation differentiation of Danxia landform was caused by the habitat differences caused by geomorphic differences. It is expected to provide knowledge for the study of mountain science, small scale natural differentiation and environmental change.