内蒙古西部地区属我国北方干旱向半干旱区生态过渡带,其生态系统服务功能的时空演变及权衡协同关系对区域生态安全与可持续发展具有重要意义。基于1990、2000、2010、2020年4期内蒙古西部地区土地利用数据,综合运用生态系统服务与权衡的综合评估(InVEST)模型与修正风蚀方程(RWEQ)模型,从碳储量、土壤保持、防风固沙及生境质量等方面,定量分析内蒙古西部地区生态系统服务的时空分异特征,并采用Spearman相关分析揭示各生态系统服务间的权衡与协同关系。结果表明:1)1990—2020年,内蒙古西部地区土地利用结构相对稳定,以未利用地和草地为主,耕地、草地和水域间转化明显。2)生态系统服务空间分布主要由生态用地变化主导,碳储量先降后升,总量下降0.55%;土壤保持量先减后增,2020年达峰值1.21×10⁹t,高值区集中于草地、耕地和林地;防风固沙量的低值区在前期呈扩大趋势,但在2020年出现急剧缩小,高值区集中在中东部;生境质量先降后升,低值区占比超60%,高值区因林地退化持续缩减。3)生态系统服务之间的权衡协同关系复杂且呈现动态变化,整体协同关系增强、权衡关系减弱。碳储量与土壤保持呈稳定协同;生境质量与碳储量呈极强协同关系;防风固沙与土壤保持协同趋势显现,与碳储量和生境质量的关系由中度权衡转变为无显著相关。应加强未利用地、耕地与草地之间的转化调控,重点保护林地,以遏制生境质量高值区缩减,并依托服务间的协同关系统筹提升碳储量、土壤保持等功能。

For a transitional zone of arid and semi-arid ecosystems in northern China,the western region of Inner Mongolia plays a significant role in regional ecological security and sustainable development due to the spatiotemporal evolution and trade-off-synergy relationships of its ecosystem services.In response to the insufficient research on the 'long-term dynamic associations of multiple ecosystem services' in this arid-semiarid transition zone,this study conducted quantitative evaluations and relationship analyses.Using land use data for the years 1990,2000,2010,and 2020 in the western region of Inner Mongolia,and integrating the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) and Revised Wind Erosion Equation (RWEQ) models,we quantitatively analyzed the spatiotemporal differentiation of ecosystem services in western Inner Mongolia with carbon storage,soil retention,windbreak and sand fixation,and habitat quality,while Spearman correlation analysis was employed to reveal the trade-off and synergy relationships among ecosystem services.The results indicated that:1) In 1990—2020,the land use structure in western Inner Mongolia remained relatively stable,dominated by unused land and grassland,with significant conversions among cropland,grassland and water area.2) The spatial distribution of ecosystem services was primarily influenced by changes in ecological land use.Carbon storage initially declined and then increased,with a total decrease of 0.55%;soil retention first decreased and then increased,reaching a peak of 1.21×10⁹ t in 2020,with high-value areas concentrated in grasslands,croplands,and forest land;the areas with low windbreak and sand fixation expanded initially but sharply contracted by 2020,with high-value areas concentrated in the central-eastern region;habitat quality showed a decreasing-then-increasing trend,with low-value areas exceeding 60%,while high-value areas continued to shrink due to forest degradation.3) The trade-off and synergy relationships among ecosystem services were complex and dynamically changing,with overall synergy strengthening and trade-offs weakening.Carbon storage and soil retention exhibited stable synergies.There was a strong synergy between habitat quality and carbon storage.The synergistic trend of windbreak and sand fixation with soil conservation had emerged,and the relationship between carbon storage and habitat quality had shifted from weak trade-offs to no significant correlation.In the future,it is necessary to strengthen the regulation of conversions among unused land,cropland,and grassland with a focus on protecting forest land to prevent the reduction of high-value habitat areas,and to rely on the synergistic relationships among services to comprehensively enhance carbon storage,soil retention,and other functions.