山水林田湖草生态保护修复工程是生态系统恢复的有效措施,借助生态保护与修复提升生态系统固碳潜力,无疑是土地利用碳减排的新路径。基于山水林田湖草沙综合整治视角,从生态系统的格局和质量两个方面评估了第一批山水林田湖草生态保护修复工程的实施效果,并借助InVEST模型定量化地分析了工程实施前后的生态系统碳汇能力。结果如下:(1)山水林田湖草生态保护修复试点工程加速了各类生态系统间的相互转化,主要表现为城镇生态系统的增加、农田生态系统的减少;工程区植被覆盖度整体提高,NDVI值平均水平不断上升、高值区逐步扩大,劣质、低质生态系统改造成果显著,陆地生态系统质量有效提升。(2)试点区生态系统碳汇能力和潜力得到有效改善,工程累积增加碳汇面积22.68%,其中工程实施前期增加碳汇面积18.06%,中后期增加面积4.62%;工程实施后2018年碳汇总量增加32.74 Tg,2020年碳汇总量增加31.28 Tg,年均碳汇潜力的提升约1.24%;工程在增加生态系统质与量、碳汇潜力的巩固与提升上具有显著成效。分析结果表明,生态保护修复是实现"双碳"目标的必然选项,这也是生态保护修复在实现"双碳"目标中的基本定位。
The ecological protection and restoration project of mountains-rivers-forests-farmlands-lakes-grasslands system is an effective measure for ecosystem restoration. Enhancing the carbon sequestration potential of ecosystems with the help of ecological protection and restoration is undoubtedly a new path for land use carbon reduction. Based on the perspective of comprehensive improvement of mountains-rivers-forests-farmlands-lakes-grasslands system, this paper evaluates the implementation effect of the first batch of landscape, forest, field, lake and grass ecological protection and restoration projects from two aspects of ecosystem pattern and quality, and quantitatively analyzes the ecosystem carbon sink capacity before and after the project implementation with the help of InVEST model. The results are as follows: (1) the pilot project of ecological protection and restoration of mountains-rivers-forests-farmlands-lakes-grasslands system accelerated the mutual transformation of various ecosystems, mainly manifested in the increase of urban ecosystems and the decrease of farmland ecosystems. The overall vegetation cover in the pilot area has increased and the average NDVI value has been rising. The high value area has been gradually expanded, the transformation of poor quality and low quality ecosystems has achieved remarkable results, and the quality of terrestrial ecosystems has effectively improved. (2) The carbon sink capacity and potential of the ecosystem in the pilot area has been effectively improved. The project has increased the carbon sink area by 22.68% cumulatively, including 18.06% in the early stage of the project implementation and 4.62% in the middle and late stages. The total carbon sink increased by 32.74 Tg in 2018 and 31.28 Tg in 2020 after the project implementation, with an increase of 1.24% in the average annual carbon sink potential. The project has significant effectiveness in increasing the quality and quantity of the ecosystem and consolidating and improving the carbon sink potential. The analysis results show that ecological protection and restoration is an inevitable option to achieve the "double carbon" target, which is also its basic position in achieving the "double carbon" target.