Ecosystem Services Evaluation Of Shiyanghe River Basin Based On RS And GIS Technology

Shiyanghe River Basin is one of the three inland rivers of Hexi Corridor in Gansu. The main ecological problems existing in Shiyanghe River Basin are water source conservation areas appeared to be breaking. The ability to retain earth and holding the water will decrease. Irrational exploit and use water resource, the water resources are serious shortage. Degeneration of grassland is very serious, the area had reduced. For the scale of the problem, to raise the awareness for ecological environment protection, to strengthen Shiyanghe River Basin's ecological restoration, there is great value in ecosystem services evaluation of Shiyanghe River Basin. Given the prominence of these issues, in order to raise people's awareness of protecting the ecological environment, strengthen ecological environment restoration in Shiyanghe River Basin, it is significant to estimate the value of ecosystem services.This paper takes Shiyanghe River Basin as research subject, based on RS and GIS, use remotely sensed data and meteorology data, by the Theory and Methods of ecosystem services evaluation, this paper carries out localization and quantitative evaluation on each term of services in the study area. The conclusions are as follows:(1)In quantity, the ecological service value per unit area in Shiyanghe River Basin is about 48.30 thousand Yuan/ (hm²·a), which is relatively low. In space distribution, the service valuations of forest ecosystem in Shiyanghe River Basin focus on the area near rivers upstream. The Downstream is low.(2) As the total amount of soil conservation in Shiyanghe River Basin, the forestland is the highest, followed by grassland. The high vegetation coverage type area can efficiently prevent and control the soil erosion.(3) Different ecosystems have different adjustment for the regional climate, either keeping cool or keeping warm. LST and DEM are similar to the regularity of temperature and elevation. There exists an obvious negative correlation linear relationship between LST and DEM. LST and NDVI have similar changing tendency. The main factors which affect surface temperature are vegetation coverage type and elevation.(4) According to the nature water holding capacity of different vegetation types, we get the value of water conservation. As the total amount of water conservation in Shiyanghe River Basin, the forestland is higher than grassland.(5)In the spatial distribution, NPP shows changing trend of first increase and then decrease. In the upper reaches of the Basin, the capability has great values which are CO₂ fixation and O₂ production, air purifying, new organic material production.With the form of currency represent the ecosystem services evaluation of Shiyanghe River Basin. According to the ecological service value per unit area in Shiyanghe River Basin, we divide the Basin into four major biochores: ecological friendly region, ecological balance region, ecological development region and ecological fragile region. The application of 3S technology in the estimate of ecosystem services value reflects that 3S technology it provides a preferable technique to quantitative and timely acquisition of the location information, data visualization and be quantitative. Width and depth of utilization of 3S in this field is expanding, which has a broad prospect and gigantic potentiality.