基于过程模型的2000—2018年中国陆地生态系统服务时空动态及其权衡与协同分析

Spatio-temporal characteristic of terrestrial ecosystem services and their tradeoffs and synergies in China from 2000 to 2018 based on a process model

2000年以来,中国陆地生态系统经历了剧烈变化并显著改变了生态系统服务。深入理解近20年中国陆地生态系统服务的时空演变格局及其权衡与协同关系对生态系统管理和可持续发展具有重要的理论和实践意义。基于最新发展的遥感驱动的生态系统服务评估过程模型(CEVSA-ES),研究定量评估了2000—2018年中国4种生态系统服务(即净初级生产力、固碳、蓄水及土壤保持)的时空格局及其权衡与协同关系。结果发现:(1)净初级生产力、固碳、蓄水及土壤保持等服务在2018的全国总量分别为3.68 Pg C/a、0.43 Pg C/a、1015.71 km^(3)/a 208.18 Gt/a;东部季风区的生态系统服务显著高于西北内陆地区及青藏高原地区,特别是热带-亚热带地区主导了中国生态系统服务供给,其对全国尺度不同生态系统服务总量的贡献率均高于50%;(2)2000—2018年,全国净初级生产力、固碳、蓄水及土壤保持均呈增加趋势,年际变化速率分别为42.80 Tg C/a、13.42 Tg C/a、11.90 km^(3)/a、1.11 Gt/a,其中净初级生产力、固碳、蓄水呈显著增加趋势(P<0.05);针对不同气候区,热带-亚热带季风区主导了净初级生产力及固碳的增加趋势,蓄水在不同气候区均呈不显著增加趋势,土壤保持仅在温带大陆性气候区呈显著增加趋势;(3)2000—2018年中国净初级生产力、固碳、蓄水、土壤保持等服务两两之间均呈协同关系。净初级生产力是众多生态系统服务的基础,其与固碳、蓄水、土壤保持两两之间均呈现显著协同关系,这奠定了不同服务之间协同关系的基础;在空间上,两两生态系统服务之间呈协同关系的面积占全国总面积的比例均超过60%,其主要分布在中国北方及长江中下游地区。本研究有助于增强对生态系统服务变化的认知,提高生态系统服务评估结果的科学性,可为生态系统管理提供参考。

Through pursuit of rapid economic development,China has lifted hundreds of millions of people out of poverty science the“reform and opening up”.However,the patterns of human development that have dominated over the past decades have resulted in dangerous depletion of natural capital and uneven delivery of essential ecosystem services.To improve the ecological environment and improve people′s well-being,the Chinese government has implemented a series of ecological protection projects since 2000.,meanwhile,China has experienced drastic environmental changes.Chinese terrestrial ecosystem services have been significantly altered.A comprehensive understanding of the spatio-temporal patterns of ecosystem services and their trade-offs and synergies have importantly theoretical and practical significance for ecosystem management and sustainable development.Therefore,a newly developed process-based model(CEVSA-ES)integrating remote sensing data was used to simulate key ecosystem services(i.e.,net primary productivity,carbon sequestration,water retention,and soil retention)in the Chinese terrestrial ecosystem.Compared to the traditional terrestrial biosphere models,the main innovation of the CEVSA-ES model was the consideration of soil erosion processes and their impact on carbon cycling.The CEVSA-ES model also improved the carbon-water cycle algorithms.We analyzed the spatio-temporal characteristic of ecosystem services and their relationships based on the simulation results of CEVSA-ES model.The results showed that:(1)net primary productivity,carbon sequestration,water retention,and soil retention of the Chinese terrestrial ecosystem in 2018 were 3.68 Pg C/a,0.43 Pg C/a,1015.71 km^(3)/a,and 208.18 Gt/a,respectively.The ecosystem services in the eastern monsoon region were remarkably higher than those in the northwest region and Qinghai-Tibet Plateau.Especially.the subtropical-tropical monsoonal region dominated the national ecosystem services.(2)The net primary productivity,carbon sequestration,water retention,and soil retention all showed increasing trends in China from 2000 to 2018.Among them,the net primary productivity,carbon sequestration,water retention showed significant trends,with increase rates were 42.80 Tg C/a(P<0.01),13.42 Tg C/a(P<0.01),and 11.90 km^(3)/a(P<0.05),respectively.For different climatic regions,the tropical-subtropical monsoon region dominated the increasing trend of net primary productivity and carbon sequestration,water retention showed no significant increasing trend in all climatic regions,soil conservation only showed a significant increasing trend in the temperate continental region.(3)There were synergic relationships among different ecosystem services in China from 2000 to 2018.Productivity was the basis for many ecosystem functions and processes,therefore,there are significant synergic relationships between net primary productivity and other ecosystem services,which laid the foundation for synergies between ecosystem services.Spatially,the areas with synergistic relationship between the two ecosystem services accounted for more than 60%of the total area of the country,where mainly distributed in northern China and the middle and lower reaches of the Yangtze River.The results could enhance the understanding of changes in ecosystem services and provide references for ecosystem management.