陕西渭北旱塬区生境质量及碳储量时空演变分析与模拟

Analysis and Simulation of the Spatiotemporal Evolution of Habitat Quality and Carbon Storage in the Weibei Dry Plateau Region of Shaanxi

探析生境质量与碳储量的时空格局演化规律,对建立陕西渭北旱塬区生态安全屏障、优化国土空间格局具有积极反馈作用.以渭北旱塬区为研究案例,基于PLUS模型模拟2035年不同发展情景下土地利用空间格局,并采用InVEST模型分析研究区1980~2020年及未来多情景下生境质量和碳储量分布特征.结果表明:①近40年间,研究区内生境质量低等级区面积扩大462.55 km^(2),碳储量共减少7.85×106 t,二者总体呈逐年下降趋势;②研究期间,生境质量降级区域集中在研究区东北部延安市域内,质量提升区域呈条状分布在靠近水源或海拔较高的地区.碳储量高值区集中分布在研究区内地势复杂、人口稀疏的区域,碳储量减少区域呈点状零散分布在研究区全域,未出现明显聚集现象;③2035年碳储量除自然发展情景外,其他状态碳储量均有不同程度减少.经济优先发展情景中生境质量低等级区面积20787.41 km^(2),是较模拟初期低等级区增速最快和高等级区减幅最大的模拟情景.研究结果可为研究区低碳绿色发展、生态修复提供决策参考和数据支撑.

Exploring the spatial and temporal pattern evolution of habitat quality and carbon storage has a positive feedback effect on establishing an ecological security barrier and optimizing the spatial pattern of national land in the WeiBei Arid Plateau Region of Shaanxi.This study took the Weibei Plateau Region as a case study,simulated the spatial pattern of land use for different development scenarios of 2035 based on the PLUS model,and used the InVEST model to analyze the characteristics of habitat quality and carbon storage distribution in the study area from 1980 to 2020 and under multi-scenarios in the future.The results showed that:①the area of the low-grade habitat quality area in the study area expanded by 462.55 km^(2),and the carbon stock decreased by 7.85×106 t over the past 40 years,both of which showed an overall decreasing trend yearly.②During the study period,the degraded habitat quality areas were concentrated in the northeastern part of the study area within Yan’an City,and the upgraded areas were distributed in strips near water sources or at higher elevations.The high carbon stock areas were concentrated in the complex terrain and sparsely populated areas in the study area,and the decreasing carbon stocked areas were scattered throughout the study area in a dotted pattern without obvious aggregation.③In 2035,carbon stock decreased to different degrees in all states except for the natural development scenario.In the economic priority development scenario,the habitat quality low grade area covered 20787.41 km^(2),which was the simulated scenario of the fastest growth rate of low-grade area and the largest reduction of high-grade area compared with the early stage of the simulation.The results of this study can provide decision references and data support for low carbon green development and ecological restoration in the study area.