基于PLUS-InVEST模型的陕南地区土地利用变化多情景模拟与碳储量评估

Land Use Change and Carbon Stock Assessment in Southern Shaanxi based on the PLUS-InVEST Model under Multiple Scenarios

在PLUS模型中纳入POI驱动因子并利用LASSO回归进行驱动体系筛选与精度验证,设定自然发展、经济保护与生态保护3种情景,利用筛选后的驱动因子模拟2030年各情景下陕南地区的土地利用格局,利用InVEST模型分析2000—2020年陕南地区碳储量的时空分异特征,探讨不同发展情景下土地利用变化对陕南地区碳储量的影响。结果表明:(1)2000—2020年,陕南地区的建设用地面积由23648.49 hm^(2)增长到78000.21 hm^(2),侵占了耕地、林地和草地的生存空间,使其分别减少了39415.05 hm^(2),8787.51 hm^(2)与17476.56 hm^(2),2030年3种发展情景下的建设用地均保持扩张的趋势。(2)在PLUS模型中加入POI驱动因子且利用LASSO算法筛选驱动因子有效提升了模型的精度与运行效率,模型的Kappa系数和OA系数分别提高了2.53%和0.20%,更精准地模拟了建设用地的分布情况。(3)2000—2020年陕南地区碳储量总量呈下降趋势,由2.1887×10^(9)t下降至2.1775×10^(9)t。2030年经济保护情景与自然发展情景的碳储量总量均小于2020年,生态保护情景下的碳储量总量最高,达到了2.1830×10^(9)t。(4)生态保护情景更有利于陕南地区的可持续发展策略,以陕南地区平均碳密度分区分布为基础,可为陕南地区分区发展与区域碳收支平衡提供参考,对未来不同情景下土地利用对区域碳储量的影响和双碳背景下的国土空间规划具有借鉴意义。

This study focuses on the southern Shaanxi region,incorporating POI-driven factors into the PLUS model and using LASSO regression for driver system selection and accuracy validation.Three scenarios,namely natural development,economic protection,and ecological protection,were set.After selecting the driving factors,the land-use pattern in southern Shaanxi in 2030 was simulated for each scenario.The InVEST model was then used to analyze the spatiotemporal differentiation of carbon storage from 2000 to 2020,exploring the impact of land-use changes on carbon storage in southern Shaanxi under different development scenarios.The results indicated:(1)From 2000 to 2020,construction land in southern Shaanxi increased from 23648.49 hm^(2)to 78000.21 hm^(2),encroaching on the living space of farmland,forest,and grassland,leading to respective reductions of 39415.05 hm^(2),8787.51 hm^(2),and 17476.56 hm^(2).In 2030,under all three development scenarios,construction land continues to expand.(2)Introducing POI-driven factors and using the LASSO algorithm in the PLUS model improved accuracy and operational efficiency,increasing the Kappa coefficient and OA coefficient by 2.53%and 0.20%,respectively.This enhancement enabled the model to simulate the distribution of construction land more accurately.(3)Carbon storage in southern Shaanxi decreased from 2.1887×10^(9)t in 2000 to 2.1775×10^(9)t in 2020.In 2030,under the three simulated scenarios,the total carbon storage in economic protection and natural development scenarios was lower than in 2020,with the ecological protection scenario having the highest total carbon storage at 2.1830×10^(9)t.(4)In 2030,the ecological protection scenario is more conducive to sustainable development in southern Shaanxi.The carbon density distribution map can serve as a reference for regional development and carbon balance,offering insights into the impact of land-use under different scenarios on regional carbon storage and spatial planning under a dual-carbon background.