Prediction of land use change and carbon storage in the context of land spatial planning:a case study of Maanshan City

The study explores the spatio-temporal evolution characteristics of land and carbon storage in Ma’anshan City under historical and future multi-scenarios, so as to scientifically and effectively formulate the policies for land use and strategies for carbon management, in hope of promoting high-quality sustainable development in the region. Based on land use data from 2000 to 2020 and the territorial spatial planning of Ma’anshan City, the PLUS model and the InVEST-Carbon model were coupled to simulate the spatio-temporal evolution of land use changes and carbon storage under natural development and planned policy development scenarios by 2030.The results indicate:(1)Over the 20 years, the main changes in land use in Ma’anshan City were the conversion of arable land, forest land, and grassland into construction land, showing a certain systemic tendency.The areas of arable land,forest land,and grassland decreased,while other land uses increased.The increase in construction land area was mainly due to the transfer from arable land. Under the natural development scenario, the historical land use change characteristics continued; under the planned policy development scenario, except for the increase in arable and forest land,other land uses decreased slightly.(2)Over the 20 years, the total carbon storage in Ma’anshan City decreased year by year, with a total loss of 6.42×10⁵t.The period from 2000 to 2010 saw the most carbon storage loss, totaling 5.62×10⁵t. High carbon storage areas were mainly distributed in higher altitude regions, while areas with increased carbon storage were mainly scattered in He County, Dangtu County, and Yushan District. The areas with decreased carbon storage were mainly concentrated in the central areas of various districts and counties. (3)Under the natural development and planned policy development scenarios in 2030, the carbon storage amounts will be 316.79×10⁵t and 318.30×10⁵t, respectively. Under the natural development scenario, regional carbon storage will continue to decline.Under the planned policy development scenario, due to the restrictions of planned policies on the uncontrolled expansion of construction land, arable land, forest land,and other high carbon density land types are protected, thus will lead to an increase in carbon storage capacity.The establishment of three control lines under the planned policy development scenario plays a key role in curbing urban carbon loss and is the best future development model for ensuring Ma’anshan’s carbon storage while guaranteeing economic development.