多情景模拟区域土地利用变化对碳储量的影响

Multi-scenario simulation of the impact of regional land use change on carbon reserve

以洞庭湖生态经济区为例,利用InVEST模型评估1990~2020年土地利用变化带来的碳储量效应,耦合Markov-FLUS模型模拟2030年、2060年在自然演变、耕地保护、生态保护、综合保护四种情景下土地利用变化及其对碳储量的影响.结果表明:1990~2020年洞庭湖生态经济区呈现出耕地、林地和草地面积减少,水域、建设用地和未利用地的面积持续增加的特征.区域内整体碳储量较高,但随着土地利用变化,造成区域固碳能力和潜力有所降低,1990~2020年区域碳储量总共减少0.433×10^(6)t.在自然演变、耕地保护、生态保护和综合保护四种不同情景下,2030年、2060年区域均表现出建设用地的变化量较大,综合保护情景建设用地的增加量得到较好控制.2030年、2060年洞庭湖生态经济区自然演变情景碳储量分别为19.927×10^(6)t、19.696×10^(6)t,耕地保护情景为19.891×10^(6)t、19.903×10^(6)t,生态保护情景为19.952×10^(6)t、19.873×10^(6)t,综合保护情景为20.004×10^(6)t、19.949×10^(6)t,相比可知在综合考虑耕地与生态保护的情景下,区域碳汇能力较强.研究结果有助于构建高碳汇国土空间格局,可为实现区域碳平衡和土地利用结构优化提供依据.

Taking the Dongting Lake Ecological and Economic Zone as an example,this study uses the InVEST model to evaluate the effect of land use changes from 1990to 2020on carbon reserve.The study also uses the Markov-FLUS model to simulate the land use changes and their effects on carbon reserve in 2030 and 2060 under four scenarios:natural evolution,arable land conservation,ecological conservation,and comprehensive conservation.The results show that the ecological and economic zone of Dongting Lake from 1990 to 2020 shows a decrease in the area of arable land,forest land,and grassland and a continuous increase in the area of the watershed,construction land,and unused land.The overall carbon stock in the region is high,but the change in land use causes the regional carbon sequestration capacity and potential to decrease.The regional carbon stock decreases by 0.433×10^(6)t in total from 1990 to 2020.Under the four scenarios,the region shows a more significant change in construction land in 2030 and 2060.In the integrated scenario,the increase of construction land is better controlled.The carbon stocks in the Dongting Lake eco-economic zone in 2030 and 2060 are respectively 19.927×10^(6)t and 19.696×10^(6)t for the natural evolution scenario,19.891×10^(6)t and 19.903×10^(6)t for the arable land protection scenario,19.952×10^(6)t and 19.873×10^(6)t for the ecological protection scenario,and 20.004×10^(6)t and 19.949×10^(6)t for the comprehensive protection scenario.Considering a comprehensive assessment that takes into account both the utilization of arable land and the preservation of ecological systems,it becomes evident that the regional capacity for carbon sequestration demonstrates a significant degree of robustness.The study outcomes contribute to the establishment of a spatial arrangement of national land areas with a high carbon sink potential,thereby serving as a foundation for attaining regional carbon equilibrium and optimizing land use structure.