Multi-scenario Simulation Prediction Of Land Use Change In Gansu Province From A Low Carbon Perspective

The rapid expansion of China’s economy has resulted in significant fossil fuel consumption,making China the world’s largest carbon dioxide emitter.Research has shown that optimizing land use structures is crucial for mitigating carbon emission and achieving low-carbon development.However,compared with global research on this topic,studies on spatial morphology are underdeveloped,with limited focus on the environmental impact of regional and urban cases.To fill this research gap,this study takes Gansu Province as an example,establishing ecological land use constraints from a carbon balance perspective,based on the relationship between carbon emission and carbon absorption by ecological land in the region.Land economic efficiency is taken as the objective function,and land use scenarios are simulated under various types of land use constraints.The results of this research provide valuable scientific references for optimizing the land use structure of Gansu Province,aiming to achieve carbon peak emission goals.The main conclusions are summarized below:(1)Between 2000 and 2020,the land use area of Gansu Province demonstrate a general trend of reducing arable and unused land,while increasing construction,forest,grassland,and water areas.The most significant increase occurrs in construction land,indicating a growing urbanization trend.Unused land has served as the primary source of renewal for the province’s other land types,playing a crucial role in balancing land supply and demand.However,construction land has expanded at the expense of ecological land,with arable land suffering the most significant encroachment.(2)The primary factors influencing carbon emissions in Gansu Province are coal consumption,the share of the secondary industry,the urban population,urbanization rate,energy consumption intensity,and regional GDP,with energy consumption intensity having a negative effect and the rest of the indicators having a positive effect.According to model predictions,carbon emission in Gansu Province will continue to increase,peaking in 2029 with 188,767,300 tons,followed by 187,479,500 tons in 2030.Regarding carbon sequestration,the amount of carbon absorption by terrestrial ecosystems in Gansu Province is insufficient to meet the current demand,and the carbon-sequestration capacity of ecosystems has also decreased slightly compared to20 years ago,with a growing gap over time.The low-carbon scenario is the only scenario in which land use changes are projected to meet the carbon uptake necessary for terrestrial ecosystems.Moreover,in this scenario,the shift from unused land to grassland is most significant.(3)There are similarities in the land use patterns observed across different scenarios,particularly the transformation of grassland,which is concentrated in the northern and southern regions of Gansu Province.In contrast,the conversion of forest land and water is more scattered and fragmented and is primarily located around the Qilian Mountains in southwestern Gansu Province.The conversion of construction land is mainly achieved through expanding on existing land,resulting in the encroachment of surrounding land to expand its own area,with arable land being affected the most significantly,which suggesting that the conflict between arable land and building land will remain in the future.