Abstract:
Ecosystem service value (ESV) is the bottom line of regional ecological security, and scientific assessment of ESV changes caused by land use change has far-reaching significance for building regional ecological security pattern and promoting sustainable development. Based on three periods of land use data from 2000 to 2020, this paper explored the impact of land use change on ecosystem service value in Chengdu by means of ESV equivalent factor, hotspots analysis and ecological contribution rate. The results showed that: (1) From 2000 to 2020, plowland and forest land were the main parts of Chengdu, and the area change was manifested as the reduction of plowland and grassland, and the expansion of the rest land. The land conversion was mainly from plowland to forest land and construction land. (2) ESV in Chengdu generally showed a trend of "first increase and then decrease", with a net increase of 203 million yuan in 20 years. In terms of ESV size, forest land > plowland > water area > grassland > unused land, the increase of ESV in forest land and water area was the main reason for the increase of ESV in Chengdu, and the sum of their ecological contribution rate was 53.66%. (3) The single ESV was dominated by regulation services, in which hydrological regulation and climate regulation were the core ecological functions of Chengdu, accounting for 57.52% of the total ESV. (4) The spatial difference of ESV in Chengdu was significant. The distribution pattern of hot and cold spots was " the west was hot, the middle was cold, and the east was not significant". The hot spots was concentrated near Longmen Mountain and water area in the west, while the cold spots was concentrated in the central urban area and shrinked towards the central urban area. These results indicated that forest and water ecosystems had a greater impact on the overall ESV. Therefore, it is the focus of environmental protection and ecological construction in Chengdu to implement reasonable and effective protection strategies and promote the development of land use structure towards the direction of ESV appreciation and preservation.