Assessing impact of land use change on ecosystem service value in Dasi River Basin of China based on an improved evaluation model.

The aim of this study was to provide a new method for dynamic and continuous assessment of ecosystem service value (ESV) and reveal the impact of land use change on ESV in Dasi River Basin within Jinan's startup area from replacing old growth drivers with new ones. Based on four remote sensing images from 2002 to 2020, four ecological indicators were extracted, and the ecological environmental quality index (EEQI) was obtained through the approach of principal component analysis (PCA). Then, the traditional ESV evaluation method was modified by using the EEQI, grain yield, the biomass factor of cropland ecosystem, and the consumer price index (CPI). Finally, the impact of land use change on ESV was further analyzed based on the improved evaluation model. The result showed that (1) during 2002-2020, the area of forestland, grassland, and built-up land showed an increasing trend. The area of cropland and bare land showed a decreasing trend, and the water body area showed a slightly decreasing trend. (2) The total ESV overall increased by 2.1759 × 10 yuan; the increased ESV from air quality regulation, maintain biodiversity, and climate regulation were the main reasons for the increased of total ESV, with contribution rates of 53.18%, 12.46%, and 11.29% respectively. (3) The sensitivity of ecosystem services to land use change showed a decreasing trend, and the order of elasticity index of different land use types was cropland > water body > forestland > grassland > bare land. The conversion of cropland and bare land to forestland was the main type of ESVs increase, with contribution rates of 18.35% and 10.13%, respectively. The cropland reclamation and built-up land expansion were the most significant land use changes that lead to the decline of ESV, with contribution rates of 20.14% and 19.03% respectively. (4) The ESV showed a significant positive auto-correlation in terms of spatial distribution. The area of high-high region was mainly distributed in water body, forestland, and its surrounding areas. The area of low-low region was mainly distributed in built-up land and wasteland areas where human disturbance is relatively serious. The high-low and low-high regions were affected by landscape transition process and randomly distributed around the low-low and high-high regions, respectively. This study cannot only put forward a new method for the dynamic continuous evaluation of ESV, but also provide a reference for the rational allocation of land resources in the startup area to realize the balanced development of regional environment and economy.