The Community Structure Of Monsoon Evergreen Broad-leaved Forest Of Lower Subtropics In China And Its Implications For The Construction Of "Near Natural Community"

Monsoon evergreen broad-leaved forest is a zonal vegetation type of terrestrial ecosystems in the subtropics of China. It has complex structure and is rich in biodiversity thus played an important role in ecosystem services. Research on this forest type thus will contribute to forest protection and management. It also serves as a reference for urban “near natural community” restroation. Plant landscaping is important in cities with “near natural community” that has low maintenance cost. It also plays an important role in alleviating the contradiction between urban development and ecological environment protection, in improving the level of urban ecological security and sustainability. Here, we studied the community composition and structure of monsoon evergreen broad-leaved forests in Dinghu mountain, Daling mountain and Baiyun mountain that were well-preserved in the south Asian tropical. Combining with the plant configuration concepts and principles of “near-natural community”, we explored the “near-natural community” species selection and spatial configuration structure, for regional urban “near-natural” construction to provide the reference. The main outcomes of this study were as follows:1. Systematically researched community physiognomy and species composition of lower subtropical monsoon evergreen broad-leaved forests in based on three sampling plots. We found that phanerophytes were dominant in the lower subtropical monsoon evergreen broad-leaved forest, and the plant communities were composed of multi-layer(tree-shrub-grass) structure and a definite number of interstratum species such as lianas, epiphytes, ferns etc. The community canopy was tidy, tall and dense through all four seasons. The species with dark green leathery leaf were the dominant tree species, and the dominate fruit types of monsoon evergreen broad-leaved forest community in south subtropics of China were drupe, berry and capsule. There were a total of 398 Species of vascular plants belonging to 92 families, 200 genera, and there were 166 species with the accumulated important value > 80%, and 58 species with important values > 5%. There are 68, 56, 41 and 34 species flowering plants, fruit plant, foliage plants and other beautiful plants(roots, stems and tree profile), respectively, in these plant species.2. We analyzed the tree-shrub-grass ratios, stratification of height, DBH, species diversity and structural stability of south subtropical monsoon evergreen broad-leaved forests in 3 sample plots. The species ratios of trees and shrubs of the three communities were between 0.48-0.95, density ratio ranged between 0.15:1-0.30:1 with a small difference; the species ratios of trees and vines was not less than 1.05:1, the ratio of the plant number was not less than 0.91:1; and the species ratio of the woody vines and herbaceous vines was not less than 2.17:1. The tree layer can be roughly divided into three sublayers, and the dominant tree sublayer was the third sublayer, and the plants with ? 7cm dominated the tree-layer. The community species richness index(R) and Shannon-Wiener index(H) of the three monsoon evergreen broad-leaved communities were as follows: achilus chinensis-Pseudosasa viridula in Daling mountain?Aporusa yunnanensis-Aidia canthioides community in Dinghu mountain?Schima superba-Psychotria rubra in Baiyun mountain, and the community Pielou evenness index(Js) of 3 monsoon evergreen broad-leaved communities was: Aporusa yunnanensis-Aidia canthioides community in Dinghu mountain?Schima superba-Psychotria rubra in Baiyun mountain?achilus chinensis-Pseudosasa viridula in Daling mountain. The three zonal plant communities Aporusa yunnanensis-Aidia canthioides community in Dinghu mountain, Machilus chinensis-Pseudosasa viridula in Daling mountain and Schima superba-Psychotria rubra in Baiyun mountain were not completely stable.3. We proposed the concept, principles and the potential plant lists of “near natural community” construction in subtropical regions of China. Near natural landscape that community canopy was tidy, green through all four seasons, tall and dense, with little rainforest characteristics was the landscape effect goal that urban “near natural community” construct in south subtropics of China. And a practically valuable potential plant list that included 347 species, belong to 92 families, 209 genera for the configuration of “near natural community” in south subtropics of China was developed. The urban “near natural community” capital trees in different soil, water, light environments were selected. Simulated monsoon evergreen broad-leaved forest community spatial structure formed the basic space structure of “near natural community”. Nine “near natural community” configuration modes were established, and their environments and possible functions were determined.