Study On The Landuse Changes And Their Effects Of Plant Diversity In Beibu Gulf Economic Zone Of Guangxi

In 2008,China have approved the implementation of "Development Planning of Beibu Gulf Economic Zone",which provides the leapfrog development of Guangxi.Since then, all kinds of infrastructure construction occupied a large amount of arable land, forest land,which lead to changes in land-use and cause great pressure to the Beibu Gulf Economic Zone ecological environment.The ecological environment has the potential of degradation and deterioration.Studying on land use change and its effects on plant diversity, which has important theoretical significance for understanding the change of ecological environment in the study area, but also can provide scientific basis for the ecological environment construction in the study area.Based on the Landsat TM images,and the field investigation date,and bu using geography information systems,the land-ues change in the distributional area of the Beibu Gulf Economic Zone was discussed,and also its drivingforces were analyzed. Then, based on the land use data, combined with factor analysis and AHP, the evaluation index system of the influence of land use on plant diversity was constructed. At last, based on the field investigation of plant community data analysis of land using changes in the types of on the effects of plant diversity, and the selection of typical plant community sample of plantation and natural forest plant diversity of detailed comparative analysis. The following results are given:1)Remarkable land-use changes had happened in the study area between the past hundred years. After experiencing the large-scale agricultural reclamation, the cultivated area of the study area turned over 2.68 times,Which from 4082.13 km in 1909 to 10922.93 km in 1986.In a large number of land reclamation activities under the drive,the other land use types in the study area have also changed greatly,particularly noticeable is the rapid decline in the area of forest land.2) Remarkable land-use changes had happened in the study area between 1990-2009. From the land use dynamic change analysis during 1990-2009, cultivated land, unused land show a decreasing trend, and the forest land, water, cursive, construction land showed an increasing trend. From the land use dynamic transfer angle analysis, the land use types in the study area were obviously transferred., including farmland, unused land transferred amount greater than the amount transferred, the amount of transferred to other types of greater than transferred amount. Construction land transfer is far greater than the output, and the annual change rate.3)The Beibu Gulf Economic Zone's variety of land use changes have a greater impact on plant diversity in the region. The constant expansion of construction land is the most important factor that affects plant diversity. The effects of land use change on plant diversity not only result in the destruction of a large number of vegetation, but also greatly reduce the diversity of plant species.4)And the natural forest is more complex than that of the plant species in the plantation.(1)Plant parts from the tree and herbaceous species and the proportion of natural forest, artificial forest proportion is large.(2)The overall composition of the plant, there are 135 kinds of plants, belonging to 67 families. There are 233 plants belonging to 87 families in the natural forest.(3)Compared with the difference of plant composition, there are 181 kinds of plants recorded in the natural forest, which are not recorded in the artificial forest, belonging to 47 families, and 83 kinds of new plant species, belonging to 27 families.