Type Structure And Function Of Land Used For Urban Main Ecological Research-by Tianxin With Changsha As An Example

With regional climate regulation,water conservation and ecological land increase space landscape types,and other significant ecosystem services,constitute the city an important component of social-economic-natural compound system.This paper by the methods of field survey,remote sensing and GIS technology,the landscape pattern analysis,five kinds of methods of ecosystem service function value,the research goal is to determine by tianxin in changsha city in 2006 and 2015,the main ecological land use type and classification,measure each type of area ratio,and build ecological land use type distribution,and estimation of the value of ecosystem services are performed.The main research results are as follows:(1)with the support of remote sensing and geographic information system software in changsha city is constructed by tianxin distribution of ecological land use types in 2006 and 2015,at the same time interpretation is:2006 and 2015,by tianxin ecological land total area of 2865.51 hectares and 2641.42 hectares,reduced 224.09 hectares of 10 years;In ecological land use type structure,its value from big to small in turn for waters(wetland),garden land,forest land,meadow.Year,only the grass area increases,the other three types of ecological land area is reduced.(2)the use of software FRAGSTATS 3.3 landscape pattern analysis are:in 2006 and 2015,the number of ecological land use patches by tianxin increased from 1717 to 3435pieces,patch density,fractal dimension increased.Can be seen from the ecological land use type distribution of the plaques are discrete,more and more patch shape becomes complex,the spatial distribution of degree of polymerization increases,explanation by tianxin ecological land is increasing year by year,fragmentation degree of landscape level degree of human disturbance;Unbalanced ecological land use types,geographically uneven distribution;Fade out the ecological functions,ecological security problem increasingly prominent problems;(3)through the ecosystem services value calculated ESV:2006 and 2015,changsha city by tianxin the ecosystem of the total service value 46.064 million yuan,42.359 million yuan respectively,general decline.Ecological land use types of ecosystem services value is in turn:water(wetland)>woodland>garden land>grassland.In 2006 and 2015,the area accounted for 36.68%of ecological land area by tianxin(wetland)and 36.34%of the water ecological service value accounted for 54.70%and 54.70%,reflects the waters in the importance of ecosystem services.Were 52.19%and 52.19%of the total area of forest land are 39.97%and 40.55%respectively in terms of ecological service function of the contribution,it shows that forest is the main carrier of by tianxin ecosystem services value.Each single ecosystem service value from big to small in turn as the climate regulation>hydrology regulation>waste treatment>gas regulating soil>keep maintaining biodiversity entertainment culture>raw materials>food production,climate regulation,hydrology regulation,waste disposal of ecosystem service value accounts for more than 50%of the ecosystem service value,raw materials and food production two less than 7%of the ecosystem service value is the sum of the two.Illustrates by tianxin production function is well below the service function of changsha,and productive function is gradually weakening trend;(4)In changsha by tianxin in view of the present existing problems of ecological land,and in combination with the practical situation of area,from the natural,social,economic and other factors to explore optimization by tianxin,ecological land use structure,perfect the function of technical means and policy measures.