Studies On Character Of Community Structure Of The Ecological Forest And Its Quality Control In Zhejiang Province

In order to comprehensively promote the construction of forestry ecosystem, optimize the structure of forest community, improve the forest quality, and enhance the forest ecological function, this research focused on the ecological forests in Zhejiang Province. Through five years study, with the help of theories such as forest community ecology, biodiversity, natural succession and natural forest sustainable development, through survey of fixed forest research plots, multichannel digital image classification, determination of chemical analysis and establishment of demonstration forest, the main research conclusions and innovative points of this paper were as follows:(1) By using the remote sensing data, forest vegetation types of Zhejiang Province were investigated with digital image classification method in three representative times of 1975, 1990 and 2003. From 1975 to 1990, the areas of non-wood forest and bamboo forest were enlarged with increases of 463907 and 79869hm2, respectively. Meanwhile, Pine forest, broad-leaved forest and open woodland were reduced with areas of 204715, 174599 and 163918hm2, respectively. From 1990 to 2003, the additions of forest were Chinese fir forest (274135hm2), non-wood forest (269439hm2), bamboo forest (240307hm2) and broad-leaved forest (218737hm2), and the reductions were open woodland forest (385145hm2), agriculture land (295562hm2) and shrubs (143206hm2). The study results were coincided with the forest production records in Zhejiang Province.The total number of forest patch increased evidently in Zhejiang in the past three decades. The patches of matured pine forest, matured Chinese fir forest, matured broad-leaved forest, matured non-wood forest were added gradually, meanwhile the open land forest was reduced evidently. The weight mean fractal dimension of patch area was from 1 to 1.35, and the bondage form of all patch types was quite regular. Most of the patch interspersion and juxtaposition index increased, and most of forest types showed a tendency of scattered distribution. Agriculture land, open woodland and matured pine forest showed quite similar landscape in comparison with the whole landscape. With the increase of time, the matured broad-leaved forest gradually became the main part of forest landscape. The steadily increasing superiority index showed that the forest ecological system of Zhejiang Province, to a certain extent, has been restored in past several decades. However, forest landscape diversity index, the uniformity index, the landscape fragmentation degree decreased gradually, and a few types of landscape dominated the whole area.(2 ) The main ecological forests in Zhejiang Province were divided into eight types,including coniferous forest, mixed coniferous and broad-leaved forest, evergreen broad-leaved forest, deciduous broad-leaved forest, mixed evergreen and deciduous broad-leaved forest, coppice shrubs on hilly land, bamboo forest, non-wood forest. According to cluster analysis, the patterns of vegetative growth in all sampling forest groups were very consistent. Due to the difference in geographic condition, although the biomass, the mean diameter at breast height and the mean tree height of all sampling groups showed somewhat discrepancy, the difference was relatively small. The main factor affecting the community character of Pinus massoniana dominated forest was soil thickness.Study result showed that the species diversity was significantly affected by the propagated strategy of species, geographic factors, soil thickness, site conditions and the human's impacts. The diversity index of understory layer among communities was in following order: evergreen broad-leaved forest > coniferous with broad-leaved species forest ( the important value of pine < 15) > coniferous with broad-leaved species forest (the important value of pine among 16~53) > pine forest > shrubs. Among the arbor layer, the dominance index value in pine forest was the highest, by contrast, the other indexes were the lowest. All indexes of MFFPT forest showed higher values, which...