基于PLUS-InVEST模型的昆明市多情景土地利用变化及碳储量响应研究

Research on Multi-Scenarios of Land Use Change and Carbon Storage Responses in Kunming Based on the PLUS-InVEST Model

摘要: 土地利用变化是影响区域生态系统碳储量的重要因素。本文以昆明市为研究区，基于2010、2015和2020年土地利用数据，以及自然、社会经济和交通区位等驱动因子，构建PLUS-InVEST耦合模型。研究分析2010~2020年土地利用变化特征，并模拟2030年自然发展、生态保护、城市扩张和耕地保护四种情景下的土地利用格局。在此基础上，评估不同情景下的碳储量响应差异。结果表明，2010~2020年，昆明市林地和建设用地面积增加，草地面积减少。土地利用变化主要表现为草地向耕地、林地和建设用地转化。2020年土地利用模拟结果的总体精度为91.34%，Kappa系数为0.8556，说明PLUS模型具有较好的模拟效果。2030年多情景模拟结果显示，生态保护情景下林地面积最大，城市扩张情景下建设用地扩张最明显。InVEST结果显示，2020年昆明市碳储量为346.417 Mt C。2030年，生态保护情景碳储量最高，为348.307 Mt C。城市扩张情景碳储量最低，为348.016 Mt C。这些结果表明，不同发展情景会改变土地利用结构，并进一步影响碳储量。保护林地等生态空间有利于提高区域碳储量，控制建设用地扩张有助于维持土地生态系统碳汇能力。

Abstract: Land use change is an important factor affecting carbon storage in regional ecosystems. Using Kunming as the study area, this study develops a coupled PLUS-InVEST model based on land use data from 2010, 2015, and 2020, together with natural, socioeconomic, and transport-location driving factors. Land use change from 2010 to 2020 was analyzed, and land use patterns in 2030 were simulated under four scenarios: natural development, ecological protection, urban expansion, and cropland protection. Differences in carbon storage responses under different scenarios were then evaluated. The results show that forest land and construction land increased from 2010 to 2020, while grassland decreased. Land use change was mainly characterized by the conversion of grassland to cropland, forest land, and construction land. The simulated 2020 land use map achieved an overall accuracy of 91.34% and a Kappa coefficient of 0.8556, indicating that the PLUS model performed well in simulating land use change. The multi-scenario simulation results for 2030 show that forest land was the largest under the ecological protection scenario, while the expansion of construction land was most pronounced under the urban expansion scenario. The InVEST results show that carbon storage in Kunming was 346.417 Mt C in 2020. In 2030, carbon storage was highest under the ecological protection scenario, reaching 348.307 Mt C, and lowest under the urban expansion scenario, at 348.016 Mt C. These results indicate that different development scenarios affect carbon storage by changing land use structure. Protecting ecological spaces such as forest land can increase regional carbon storage, while controlling construction land expansion can help maintain the carbon sink capacity of land ecosystems.