Modelling the potential impacts of urban ecosystem changes on carbon storage under different scenarios by linking the CLUE-S and the InVEST models

Carbon storage plays an important role in urban ecosystems. However, urban expansion leads to urban ecosystem changes and hence directly threatens carbon storage. Therefore, modelling the potential impacts of urban expansion on carbon storage is necessary. This study links the Conversion of Land Use and its Effects at Small regional extent (CLUE-S) model and the Integrated Valuation of Environmental Services and Tradeoffs (InVEST) model to analyze the potential impacts of urban expansion on carbon storage in Changsha-Zhuzhou-Xiangtan urban agglomeration from 2014 to 2023 under three urban expansion scenarios, namely Natural Increase Scenario (NIS), Cultivated Protection Scenario (CPS), and Ecological Protection Scenario (EPS). The results indicated (1) carbon storage of Changsha-Zhuzhou-Xiangtan urban agglomeration experienced a loss of 8.64 Tg from 1995 to 2009; (2) from 2014 to 2023, the carbon storage will experience the most loss of 8.54 Tg under the NIS, will experience the least loss of 7.12 Tg under the EPS, and will experience moderate loss of 7.92 Tg under the CPS; (3) the conversions of green land ecosystem and cultivated ecosystem to built-up ecosystem are the main cause of regional carbon storage loss in Changsha-Zhuzhou-Xiangtan urban agglomeration; (4) the carbon storage loss will primarily occur in the junction region of Changsha-Zhuzhou-Xiangtan urban agglomeration because every city is incline to expand toward other cities in an urban agglomeration system. We argue in favor of integrating multiple ecosystem services into urban land use planning to obtain a sustainable development.