The Study Of The Land Use Change And The Ecosystem Services Value In Xunyang County

In this paper, the study takes Xunyang County as the research area and combines with the remote sensing data and social economic data to analyze the nearly 15 years’land use data of Xunyang County, which is based on the table of equivalent value per unit area of ecosystem service value in 2015. It also uses per unit area of farmland yield, biomass and vegetation coverage in typical mountainous area ecosystem service value of Xunyang County to achieve the correction of downscale from the whole nation to the regional area and to the grid, mixed with wheat, corn, rice, and sweet potato in the study area economic value per unit area of the four major food crops to determine one equivalent factor of Xunyang County, whose per unit area economic service value is 942.70 yuan/hm2. Based on this, we can account its ecosystem value in 2000-2015 and analyze its changing rules and finally know the relationship between the land use and the ecosystem service value based on grey prediction model to predict its ecosystem service value in the next 10 years and put forward the decisions of the corresponding land use of Xunyang County and management suggestions on the basis of sustainable development.These main conclusions are as followings:(1) In 2000-2015, the land use change of Xunyang County presents a balanced tendency of "three increasing and three decreasing". During the 10th five-year period, the implement of reverting farmland to forestland (grassland) and the project of deverting water from the south to the north caused the largest reduction in cultivated land, while it caused the largest increase in water areas. However, during the 11th five-year period, the land use change presents the tendency of "four increasing and two decreasing", but the variation is not obvious.which means all kinds of land use area keeping a stable development tendency. But, during the 12th five-year period, six types of land use took place change dramatically in Xunyang County, especially the area of forestland dropped sharply.(2) During the research period, the comprehensive development level of various land use types in the whole county shows a gradually progressive momentum. And the degree of land use is at a medium or above level. However, the comprehensive utilization of forest land was reduced by increasing in 2000-2015, which means forestland goes into a recession period at that time.(3) Overall, Its ecosystem service value presents the shape of pyramid, namely it shows a slow reduction trend that increases first and then decreases in 2000-2015. The ecosystem service value of forestland, water area, and grassland increased substantially, which made the total value increased by 0.102 billion yuan. In the second five years, the study area of ecosystem service value continuously maintained on the rise.Compared the previous 5 years, the level of increase is slower slightly. In 2010-2015, though the ecosystem service value of farmland increased somehow, the loss of forestland’s ecosystem service value caused a sharply decreased tendency at that time, whose total value decreased by 0.16 billion yuan.(4) The maintain of bio-diversity and soil conservation of Xunyang County’s individual ecosystem always place the top2. In addition, farmland and grassland mainly service soil conservation, while farmland and grassland mostly service soil conservation, and forestland and unused land lie in the maintain of biodiversity. The service function of water area is mainly to keep water conservation, especially its entertainment and culture value plays an important role in the green industry, such as regional tourist development.(5) During the research period, the faster increased area of all towns in Xunyang County mainly lies in ecologically fragile area of Ba Mountain area and the river corridor of meadow, Xun river and Hanjiang River. It shows Xunyang County insists on the principle of "protection on the surface and key development" in ecologically fragile limitation area. At the same time, Xunyang County makes full use of land resources to the benefits of ecosystem environment in densely population area.(6)The correction between the land use and ecosystem service value in order: forestland>grassland>cultivated land>water area>construction> unused land, which shows forestland has a big effect on the regional ecosystem service value. The ecosystem service value will be on the rise in the next 10 years, respectively,7.479 billion yuan and 7.700 billion yuan. The accuracy verification shows the prediction results are reliable.