A Study For Ecosystem Service Balance Between Supply And Demand In Yulin City

The ecosystem could be definited as a kind of life support system, which is supporting people survivals and social developments. To some extent, human being bringed desturction to ecosystem at the time of asking for and enjoying various survies from natural resources, human beings bringed destruction as well. The former scholars mostly concentrated on the supply of ecosystem services. Recently, some of learners started to pay their attention on the status of supply and demand of ecosystem services. However, the establishment of the supply and demand index system cannot achieve a good mutual docking.This article took the main line of eco city construction, according to the 30m spatial resolution of TM remote sensing image data in Yulin City at the year of 2005,2009 and 2013, based on the valuation of ecosystem services in Yulin city in those years, the functional equivalence method was used to analyze the spatial and temporal variation characteristics of the Yulin City's ecosystem services, and from the human needs of service function, this paper improved the index system of original ecosystem services needs'assessment. Referring to the relevant indicators of eco city construction, the balance of supply and demand of ecosystem services in Yulin city was evaluated by functional equivalence. The results as follow:(1)Yulin City's ecosystematical service value is showing the growth trend, the whole value of Yulin City's ecosystem service respectively displayed the results as 69.43 × 108 Yuan, 259.26 × 108Yuan,775.65 × 108 Yuan in 2005,2009,2013 year, the function equivalent respetively showed as 227055.24,584196.96,1070334.50;(2) From the point of view of ecosystem service types, unit area of ecosystem service function equuvalent from the largest to small as water> forest land> grassland> plowland> bare land> construction land, therefore, water has the most important status;(3) From the time, it showed that the unit gridding average value reached III level as the intermediate level in the year of 2005, it touched V level as the advanced level in the year of 2009 and 2013, and the V level proportion achieved 28.70% in the year of 2013. However, on account of contruction land had rapidly increase those years, the I level as the lowest proportion had rapidly increased, and around to be 13.56%;(4) From spatial variation, the advanced equivalent mostly at Qingjian County, Suide County, Zizhou County, Mizhi County and Jia County, and east of Jingbian County, south of Shenmu County and the area of each hydrographic net throughed. The low level function equtvalent mostly distribute to a large area of contruction land, such as:middle of Shenmu County, south of Yuyang District, north of Hengshan County and north of Dingbian County;(5) the total equivalent weight of Yulin City's ecosystem service is 1070334.50, the demands' equivalent is 7275907, the ecological gap is showing a number as 6205572.5, it displayed that quantity demand is greater than the supply of ecosystem services, which is not conform to the request of Yulin City's sustinable development, and has yet to eninforce ecological remediation and protection;(6) for the current situation about the Yulin City ecosystematical service function's supply less than demand, this paer analyzed the open question about ecosysetm and come up with some ideas to ecological remediation and countermeasure.