【摘要】 土地利用变化对生态系统碳储量的时空变化具有直接影响。由于以城市群为代表的快速城市化地区的主导功能并非提供固碳等生态系统服务，因而对其研究相对较少，更多关注流域、湿地、山地等重要生态保护地土地利用变化对碳储量的影响。然而，这类区域生态系统固碳具有变化过程快、变化程度强烈的特征，对碳储量具有重要影响，因而有待于进一步研究。本文利用InVEST模型分析成都平原经济区2000—2020年碳储量的时空演变，探究土地利用变化对碳储量的影响，利用PLUS模型预测2030年不同情景下土地利用变化和碳储量的时空变化。结果表明：(1)20年间，研究区土地利用变化显著，主要表现为建设用地翻倍增加，耕地面积大量减少。(2)2000—2010年碳储量小幅上升(0.18%),2010—2020年碳储量小幅下降(0.76%),生态系统固碳能力有所下降。其中，碳储量减少区主要位于各城市中心城区和雅安市西部的山地；碳储量减少主要源于建设用地快速扩张和耕地被大量占用；退耕还林虽增加了生态系统固碳能力，但林地开垦为耕地或转化为草地又抵消了退耕还林带来的碳储量增加。(3)经济优先的政策情景将导致建设用地侵占林地和耕地，部分质量较差的森林向草地转化，碳储量显著下降，且下降总量是前20年下降总量的1.7倍；严格限制新增建设用地政策和生态建设工程的实施，可增强生态系统固碳能力，并助力成都平原经济区“双碳”目标的实现。本研究可为成都平原经济区自然资源管理、国土空间规划及“双碳”目标的实现提供科学依据。更多还原

【Abstract】 Land use change has a direct impact on spatio-temporal changes in ecosystem carbon stocks(ECS). Since the dominant function of rapidly urbanizing regions represented by urban agglomerations is not the provision of ecosystem services such as carbon sequestration, relatively few studies of related had been carried out on them, with more attention being paid to the impact of land-use changes in important ecological reserves such as watersheds, wetlands and mountains on carbon stocks. However, carbon sequestration in ecosystems in such urbanizing regions is characterized by rapid and strong processes of change, with important implications for carbon stocks, and thus requires further study.In this study, it analyzed the spatio-temporal changes in carbon stocks in Chengdu Plain Economic Zone(CPEZ) from 2000 to 2020 using InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs) model, and examined how land use changes influenced these carbon stock changes. Then it predicted the spatio-temporal changes of land use with resulting changes in carbon stocks under different economic and ecological scenarios in 2030 using a PLUS model.It found that(1) There were a remarkable changes in land use in CPEZ, manifested by a nearly twofold increase in construction land and a substantial decrease in cropland from 2000 to 2020.(2) Carbon stocks increased slightly(0.18%), then followed by a decline(0.76%), with a net loss of 16.80×10~6 t from 2000 to 2020. This indicated that the Zone shifted from a carbon sink to a carbon source, and the carbon sequestration capacity declined. Spatially, the decrease in carbon stocks occurred mainly in the urban areas of CPEZ and the mountainous areas in the west of Ya’an city, which was mainly due to the rapid expansion of construction land and the large occupation of cultivated land. Although great efforts in afforestation and reforestation positively increased the carbon sequestration capacity of ecosystems, the reclamation of woodland for cultivated land or conversion to grassland unavoidably offset the increase.(3) Supposing a policy scenario of economy priority in CPEZ, it will lead to the encroachment of construction land into forested and cultivated land, the conversion of some of the poorer quality forests into grasslands, and a significant decline in carbon stocks, with the total decline being 1.7 times that of the total decline in the previous 20 years. The implementation of a policy of strictly restriction to the increase in construction land and ecological restoration by protection projects will enhance the capacity of the ecosystem to sequester carbon and help realize “Carbon Peak and Neutrality”target of the Chengdu Plain Economic Zone.This study can provide a scientific basis for natural resource management, territorial spatial planning and the realization of “Carbon Peak and Neutrality”target in the Chengdu Plain Economic Zone.更多还原