Analysis And Evaluation On Greening Plants And Plant Landscape In Residential Quarters Of Nanning

Landscaping can improve the value and change the appearance of residential quarter,and it is also the important measure to upgrade environmental quality. Greening plants arethe main body of landscaping, the abundant plants can construct various plant communitiesand exhibit colorful plant landscape by scientific and organic arrangement. The greeningplant species applied in 28 residential quarters were studied in this paper. The speciescomposition, the physiognomy, the ecological structure and the community diversity of allthe 134 ornamental plant communities were analyzed starting with community structure,and the plant landscape of 28 typical ornamental plant communities were evaluated by"The AHP model of landscape evaluation of garden plants". The main results are asfollows:(1) There are 390 species of greening plants which belong to 240 genera and 96families appeared in 28 residential quarters of Nanning. Among them, 157 species werenative plant species of Guangxi, 53 species were introduced from other regions of China,and 180 species were introduced from foreign countries, they accounted for 40.26%,13.59% and 46.15% of total plant species. The life-form composition of the 390 species is137 species of arbor, 109 species of shrub, 18 species of liana, 14 species of bamboo, 29species of palm, and 83 species of herb.(2) There are less greening plant species applied in each residential quarter. Themaximum is 191 species, the minimum is 46 species, and the average is 88 species amongthe 28 residential quarters. The life-form of shrub was mainly applied in most of theresidential quarters, the number of shrub species is more than any other life-forms.(3) Among the 134 ornamental plant communities in 28 residential quarters, the ratioof the plant communities dominated by evergreen species and that dominated by deciduousspecies is 5.09:1, and the ratio of the plant communities dominated by broad-leavedspecies and that dominated by conifer species is 133:1, so it form a communityphysiognomy giving priority to evergreen broad-leaved species.(4) The structure of the ornamental plant communities in residential quarters ofNanning is mainly on multi-stratum structure which is comprised of tree layer, shrub layer and herb layer. Among the 134 omamental plant communities, there are 113 communitiesthat has a structure of "tree-shrub-herb", and has a proportion of 84.33%; there are 15communities that has a structure of"shrub-herb", and has a proportion of 11.19%; there are3 communities that has a structure of "tree-shrub" and 2 communities that has a structureof "tree-herb", they have a proportion of 2.24% and 1.49% respectively; there are only 1community that has a single layer structure of herb, and has a proportion of 0.75%.(5) By the analysis and contrast on the community diversity indices of tree layer,shrub layer and herb layer of the 134 ornamental plant communities, the results show thatPatrick index S having biggish difference of tree layer, shrub layer and herb layer indifferent community: the Patrick index S mainly concentrates on 1-2 in tree layer, whileconcentrates on 3～9 in shrub layer and 10～22 in herb layer. The da, H', D, J_sw and J_siindices have the same change tendency among tree layer, shrub layer and herb layer indifferent community, they increase with the rise of Patrick index S.(6) The results of species richness, species diversity and species evenness of tree layer,shrub layer and herb layer of ornamental plant communities are:①The herb layer has thehighest species richness, shrub layer is secondly, and the tree layer is the lowest;②TheShannon-Wiener index H'of species diversity is in the order: herb＞tree＞shrub, and theSimpson index D of species diversity is in the order: shrub＞tree＞herb;③The Pielouindex J_sw and J_si of species evenness is in the order: shrub＞tree＞herb.(7) The evaluating result on plant landscape of 28 typical ornamental plantcommunities show that: the average score is 7.332, the maximum is 7.917, and theminimum is 6.009. The landscape grade of ornamental plant communities concentrates onⅢandⅣ, the number of communities which belong to gradeⅢis 24, while the numberof communities which belong to gradeⅣis 4.In order to improve the landscaping level and promote the scientific, ecological andsustainable development of landscaping construction in residential quarters, some adviceson selecting the greening plant species, optimizing the structure of ornamental plantcommunities and enriching the plant landscape in residential quarters were put forwardbased on the research on plant community and the evaluation on plant landscape.