Study On Species Diversity Of Urban Forest Of Karst Vegetation In Guiyang

Urban is a relatively large, densely populated environment massed by people. Urban forests play a significant functioning role in sustainable development cities, but for various reasons, the city environmental problems have become increasing prominent. Voice of "introducing forest into urban" and building urban forest ecosystem will improve the city’s environment and promote the coordinate development between man and nature, which plays an important role. The Karst area within Guiyang, the capital city of Guizhou Province, accounts for85%of the total urban area of the total city and is so-called a "wonder of green" in Karst landform. The niche diversity and vegetation types are rich in Karst of Guiyang. Therefore, studying the characteristics of different types of vegetation diversity restoration in Karst areas, and opening out the ecology rule and the character which can provide the important academic basis for combating the Karst. In this study, the structure and composition of forest were investigated in main seven forest types in Guiyang. The main results showed:1. In seven types of forest communities, shrubbery composed of Pyracantha, Rubus foliolosus, Viburnum ternatum, Lonicera Japonica, Lagerstroemia indica, etc., belonging to14families and19genera and20species of the herb layer. The grass layer consists of Miscanthus floridulus, Hemarthria vaginata, Artemisia argyi, belonging to4families5genera and6species; the camphor forest’s tree layer is composed of the camphor tree, shrub layer is mainly composed of Pinus massoniana, Camellia, fir and Rubus niveus, belonging to5families5genera and5species, herbaceous layer mainly by the composition of Primula malacoides, Erigeron annuus, Pteridium aquilinum, Miscanthus floridulu belonging to5families,8genera and9species; In Poplar forest, tree layer is mainly composed of poplar, shrub layer is mainly composed by the Serissa, Camellia oleifera, Pinus massoniana, belonging to7families and9species, the herb layer is mainly composed of Lophatherum gracile, Imperata cylindrica, Sambucus chinesisl, belonging to8families and9genera and9species; In Quercus acutissima Carr. Forests, the tree layer is mainly composed by Quercus acutissima, fir, shrub layer mainly by the composition of tQuercus acutissima, fir, Serissa, belonging to14families20genera and20species, the herbaceous layer composed of Hemarthria protensa, which belongs to4families5genera and6species; In Robinia pseudoacacia+Catalpa ovata forests, the tree layer is mainly composed of of Catalpa ovata and Robinia pseudoacacia, the shrub layer is mainly composed of Zanthoxylum simulans, Rosa multiflora, Cayratia japonica, etc., belonging to3families5genera and5species, the herb layer is mainly composed of Bupleurum, Iris, Hemarthria vaginata, belonging to4families4genera and4species; In Betula luminifera and Italian Poplar mixed-forests, the tree layer mainly composed of masson pine, Betula spp and Italian Poplar, the shrub layer is mainly composed of Castanea sativa, Paulownia and Quercus, belonging to12families and16genera and17species, herbaceous layer is mainly composed of Pteridium aquilinum, IHemarthria protensa, etc., belonging to4families6genera and six species; In Fir and Broad-leaved Trees Mixed Forests, the tree layer is mainly composed by masson pine, catalpa tree and wild Cerasus, the shrub layer is mainly composed of Zanthoxylum, Corylus chinensis, belonging to7families7genera7kinds, the herb layer mainly composed of Dryopteris, Bupleurum, which belongs to the4families,7genera and seven species.2. The single species took the absolute dominance in the Camphor, Poplar, Black Locust and Ovate Catalpa plantation. The species of shrub layer was the most. The species of herb layer was less. The arbor and shrub layer of Sawtooth Oak, Betula luminifera and Italian Poplar mixed forest, mixed coniferous broad-leaved plantation had higher species diversity; Community structures were relatively simple, making up of arbor layer, shrub layer and herb layer.3. To study the seven community revealed that the order of the species diversity was in the following:herb layer> shrub layer> arbor layer in the Camphor and Poplar plantation; shrub layer> herb layer> arbor layer in shrub forest, Sawtooth Oak, Black Locust and Ovate Catalpa, Betula luminifera and Italian Poplar mixed plantation. The seven communities revealed that the order of the evenness was complex and diversity. Relatively speaking, the evenness of shrub layer is completely different but small difference in arbor layer and herb layer.4. From largest to smallest order of7different forest stands species richness index: Quercus acutissima Forest> Fir and Broad-leaved Trees Mixed Forests> Betula luminifera and Italian Poplar Mixed Forests> poplar Forest> shrubbery> Camphor Forest> Robinia pseudoacacia+Catalpa ovata Forests, the size of the order of the Shannon-Wiener diversity index:Fir and Broad-leaved Trees Mixed Forests> poplar forest> Shrubbery> Betula luminifera and Italian Poplar Mixed Forests> Populus Forest> Robinia pseudoacacia+Catalpa ovata Forests> Quercus acutissima Forest> Camphor Forest; The size of the uniformity index in order: Shrubbery> Robinia pseudoacacia+Catalpa ovata Forests> Poplar forest> Fir and Broad-leaved Trees Mixed Forests> Betula luminifera and Italian Poplar Mixed Forests> Quercus acutissima Forest. In each diversity index, Shannon-wiener index can reflect the actual situation of, other index has more or less a certain fluctuation.5. The β diversity index of Betula luminifera and Italian Poplar mixed-forest and Sawtooth Oak forest is the highest. It showed maximum degree of similarity, maximum of habitat and minimum heterogeneity between these forests. Other β diversity index in an order as mixed coniferous broad-leaved plantation and Betula luminifera and Italian Poplar mixed forests(0.41)> mixed coniferous broad-leaved plantation and Sawtooth Oak forest(0.36)> Sawtooth Oak forest and Camphor forests(0.35)> Black Locust and Ovate Catalpa forests and shrubby(0.34)> mixed coniferous broad-leaved plantation and Black Locust and Ovate Catalpa forests(0.33)> Betula luminifera and Italian Poplar mixed forests and Poplar forest(0.33).6. Compared to other regions of Karst City, the urban forest diversity index in Guiyang (Shannon-Wiener index) is generally smaller than Karst region of Maolan, and smaller different than mountain grassland plantation in Karst of Guizhou. And compared to the non-Karst region, the urban forest biodiversity index in Guiyang is general higher than the regions at the same latitude.