Study On Eco-environment Effect Of Land Use Change In Hangzhou Bay

Land is the most basic natural resources,it plays an extremely important role in human survival and development.Land use change is the result of human activities and nature and the regional environment will respond to the change of land use.As an important part of the Yangtze River Delta urban agglomeration,the Hangzhou Bay area has a relatively rapid economic development and a high level of urbanization.The construction of the city is in a leading position in the country.The land has undergone tremendous changes,which has also produced a series of ecological environments.The problem seriously threatens people's survival and sustainable development.Under this large social background,this article scientifically analyzes the eco-environmental effects of land use changes in Hangzhou Bay to make the planning of the Land use more reasonable and the protection of the eco-environment more sustainable.In this article,7 cities and 47 districts and counties were selected as the example.This article is based on Landsat TM/OLI satellite image data and human and social statistics of Hangzhou Bay area in 2000,2005,2010 and 2015,four periods of land use data in the Hangzhou Bay area were calculated.At the same time,referring to previous studies,combining remote sensing and geographic information technology,and using research methods such as literature and comparative research methods and so on to study the eco-environmental effect of land use change in Hangzhou Bay area between 2000 and 2015.According to the results,some suggestions are given.The main results are as follows:(1)Generally speaking,the types of land use/cover in the Hangzhou Bay area are relatively rich.They are mainly cultivated land and forest land,and their combined areas cover more than 65%.During the past 15 years,cultivated land,forest land,grassland,unused land and water body in Hangzhou Bay area showed a decreasing state,while construction land showed an increasing state.From the perspective of the transition matrix,construction land was mainly transferred from cultivated land and forest land.Rapid economic development has led to the occupation of large amounts of cultivated land and forest land by construction land.(2)From the perspective of ecosystem service value,from 2000 to 2015,the ecosystem service value of Hangzhou Bay area showed a trend of first increase and then decrease.Among them,the ecosystem service value of the forest land is relatively large,and the proportion of each year is higher than 60%.At city scale,the ecosystem service value in Hangzhou,Ningbo,Shaoxing and Zhoushan increased first and then decreased from 2000 to 2015.At the sane time,the ecosystem service value in Shanghai,Jiaxing,and Huzhou has shown a continuous decrease between 2000 and 2015.At county scale,from 2000 to 2015,the ecosystem service value of per unit area was in a state of decline,among which the ecosystem service value of per unit area was less than 10,000 yuan /hm2,mainly concentrated in Shanghai and Jiaxing.(3)From the perspective of ecosystem health,the overall ecosystem health value of Hangzhou Bay area decreased from 2000 to 2015.At city scale,the ecosystem health status of each city has deteriorated significantly,with the ecosystem health value mainly concentrated between 0.5 and 0.7.By 2015,ecosystem health in all cities had reached historical lows.At county scale,the overall ecosystem health level showed a trend of improvement from the coast to the landlocked from 2000 to 2015.From 2000 to 2105,the number of districts and counties with relatively well and well level decreased from 32 in 2000 to 20 in 2015,and the area decreased by about 24.64%.The number of districts and counties with relatively weak and weak level increased from 1 in 2000 to 13 in 2015,and the area increased by about 16%.By 2015,districts and counties with ordinary or lower level of ecosystem health were mainly concentrated in the north of Shanghai,Jiaxing,Shaoxing,and Ningbo.Among them,the districts and counties along the coast of the Hangzhou Bay Greater Bay Area were all at ordinary or relatively weak level.