基于土地利用变化的长江上游生态系统服务价值核算及预测模拟

Accounting and Predicting Simulation of the Ecosystem Service Value in the Upper Reaches of the Yangtze River Based on Land Use Change

为研究长江上游地区土地利用变化对生态系统服务价值(ESV)的影响,基于GIS网格空间可视化表达技术,以土地利用和社会经济为数据源,采用土地利用动态度、ESV评估模型和空间自相关模型等方法,对研究区土地利用动态度和ESV时空变化特征及二者的相关性进行研究。结果表明,1)长江上游地区林地和草地是最主要土地利用类型,2000-2020年,林地、水域、建设用地、未利用地面积呈现增加趋势,其中建设用地面积在2020年较2000年增加148.66%,耕地和草地的面积呈现减少的趋势;2)在2050年未来气候情景下各类型土地利用变化差异较为显著,耕地、水域、建设用地和未利用地面积均减少,变化速度最快的是水域,而林地和草地面积呈增大趋势,未来2个不同气候情景下的土地利用综合变化速度稳定在0.80%~0.92%;3)长江上游地区土地利用存在很大开发潜力,2000-2020年及2050年未来气候情景下土地开发以中低强度为主,而高强度等级土地利用聚集分布于四川和重庆,特别在2050年未来2个气候情景下区域极核分布更为显著,需引起高度重视;4)研究区单位面积ESV以中和较高等级为主,总ESV稳定在80000亿元以上,呈先增后减的趋势,但空间分异较为显著,其中长江上游中部山地以及青藏高原部分区域单位面积生态系统服务价值较高,而四川、重庆主城区是较低和低级生态系统服务的集中分布区域,在未来气候变化下ESV呈下降趋势,中等排放情景ESV小于低排放情景ESV;5)ESV与综合土地利用强度呈正相关性,空间上主要以高-高聚集、高-低聚集和低-低聚集分布为主,高-高型主要分布于青藏高原和横断山脉的部分地区,高-低型集中分布于经济发展较快的四川、重庆地区,低-低型分布于草地广泛、经济发展较为落后的青藏西北地区。研究结果揭示了长江上游地区2000-2020年及未来气候变化下ESV与土地利用动态的时空演变规律及其相关性,可为制定科学合理的地区生态保护政策、建立生态保护修复的长效机制提供科学依据。

To explore the influence of land use change on ecosystem service value(ESV)in the upper reaches of the Yangtze River,the spatial and temporal change characteristics of land use dynamics and ESV in the study area and the correlation between them were investigated based on GIS grid spatial visual representation technology,using land use and socio-economy as data sources,and using land use dynamics,ESV assessment model and spatial autocorrelation model.The results showed that 1)forest and grass lands were the major land use types in the upper reaches of the Yangtze River,and the area of forest land,water area,construction land and unused land showed an increasing trend from 2000 to 2020,among which the area of construction land increased by 148.66%in 2020 compared with 2000,and the area of arable land and grassland showed a decreasing trend.2)Under the future climate scenario in 2050,the differences of land use changes of each type would be more significant,the area of cropland,water area,construction land and unused land all would decrease,and the fastest change would be in water area,while the area of forest and grass lands would present an increasing trend,and the comprehensive change rate of land use under two different climate scenarios in the future would be stable at 0.80%-0.92%.3)The land use in the study area had great development potential.The land development during 2000-2020 was mainly in low to medium intensity,so would be in the future climate scenarios of 2050.while the high intensity land use would be concentrated in Sichuan and Chongqing,especially in the future two climate scenarios of 2050,the regional extreme core distribution would be more significant,which needs to pay great attention.4)The ESV per unit area in the study area was mainly in medium and high levels,and the total ESV was stable above 8 trillion yuan,with a trend of increasing and then decreasing,but the spatial divergence was significant,among them,the value of ecosystem services per unit area was higher in the central mountainous areas in the upper reaches of the Yangtze River and some areas in the Qinghai-Tibet Plateau,while the main urban areas in Sichuan and Chongqing were the concentrated distribution areas with low and medium level ecosystem services,and the ESV would be decreasing under future climate change.5)ESV was positively correlated with integrated land use intensity,and spatially it was mainly distributed in high-high aggregation,high-low aggregation and low-low aggregation,high-high type mainly distributed in the Qinghai-Tibet Plateau and parts of the Hengduan Mountains,high-low type concentrated in the urban areas of Chongqing,Sichuan,where economic developed highly.The study reveals the spatial and temporal evolution patterns of ESV and land use dynamics in the upper reaches of the Yangtze River in 2000-2020 and under future climate change,which can provide scientific basis for formulating scientific and reasonable regional ecological protection policies and establishing long-term mechanisms for ecological protection and restoration.