Study On The Evolution Of Land Use And Living Vegetation Volume Around Wuhan Lake Area

The lake is a very important survival base for human beings.Protecting lakes mutually promotes and restricts the development of cities.With the development and construction of city,Lakes within the city are constantly shrinking with the hard lakeshore zone.Due to the reduction of green area and lower greening level,ecosystem suffered serious damage.Especially,Wuhan famed for "Thousands of lakes" is weakening its advantage and has the weak competitiveness and vitality.Aware of the seriousness,the Wuhan municipal government has launched a series of projects for the protection and restoration of lakes.Taking Wuhan as an example,this paper studies the law of the ecological change in lake shore area in terms of the land use and the GVV evolution,and finally puts forward some suggestions to protect the green space in lake shore area.Most of the researches on the green belts are mainly two-dimensional,ignoring the ecological differences in different communities.Therefore,the research in this paper includes the evolution of two-dimensional green space and three-dimensional GVV.According to the image of lake itself and lake shore area from 1994 to 2014,taking 13 typical lakes in Wuhan city as the research object,this paper analyzes as follows:(1)conditions of land use are classified from the images and the structure of land use and the direction of the green-land transfer are compared horizontally and vertically.(2)the NDVI values of the vegetation cover area in each period were extracted,and the LAI values of each point were calculated by using the LAI-NDVI inversion equation,thus calculating the total green volume and green area rate of each region.(3)according to the value of LAI,the vegetation cover is divided into three grades:high,middle and low green volume so as to compare the change of green quantity distribution in each period.(4)land use and the evolution of GVV in 13 lakes was analyzed.Through the above research,we can draw the following conclusions:(1)the land use structure in Wuhan Binhu District has changed violently.The water and green area has been reduced greatly.The hard area has increased by 1.5 times with the lower proportion of green land and farmland.Among them,the lakes in the fast developing area are changing violently.Green space is transformed into the hard area and lakes turn to farmland and hard zone.(2)GVR in lake shore area is low.The construction of the park plays an active role in improving the green volume rate.(3)the middle-level green area is greatly reducing.The GVR in each lake area is relatively different,especially in Hanyang Lake area and Wuchang district.The rapid change of hardness has a great influence on the green volume rate.(4)the establishment of scenic spots and parks can effectively protect and restore lakes and lake shore green area,but it takes years of efforts to have some achievement.In view of the above conclusions,suggestions for the protection and restoration of the green belt around the lake in Wuhan are put forward.