Evolution and multi scenario simulation of land use carbon emission pattern in Hebei Province under carbon neutral target

Carbon emission has been posed a great challenge on the goals of carbon peaking and carbon neutrality. Low-carbon spatial pattern can be optimized to construct the national evolution of carbon emission from land use. In this study, the direct-, indirect-, and net carbon emissions were calculated for the land use in Hebei Province of China from 2000 to 2020, according to the carbon emission coefficients of land use types, energy consumption, and agricultural activities. The spatial pattern evolution was also achieved using GIS software and the PLUS model. Three development scenarios of land use patterns were simulated in the study area in 2030 and 2060. The carbon emissions were then calculated under different scenarios of ecosystem carbon sequestration management. The results were as follows: The direct carbon emissions from land use were remained basically stable at −2.43 million −2.5 million t/a in the study period, indicating the carbon absorption. Indirect- and net Carbon emissions from land use showed a continuous increasing trend ranging from 86.198 million t in 2000 to 267.142 million t in 2020. But the increasing speed decreased outstandingly, whereas, the net carbon emissions from land use depended mainly on the carbon emissions from energy consumption. There was the basically stable spatial distribution of grid units at the various levels of carbon emission. Specifically, the grid units of carbon absorption were concentrated in the Taihang Mountain area of Yanshan Mountain, while the grid units of low net carbon emission were distributed mainly in the southeast plain, the medium net carbon emission was found in the rural residential areas and the Bohai Rim region, and the high net carbon emission was in the surrounding cities of Shijiazhuang, Langfang, Baoding and some county central cities. There was a shrinking trend of space in the carbon absorption area and medium net carbon emission grid units. By contrast, an expanding trend in space was found in the low, medium high, and high net carbon emission grid units. The largest proportion was accounted in the carbon absorption areas and low net carbon emission grid units in the study area. But the net carbon emission often occurred in the middle and high net carbon emission areas and high net carbon emission grid units. The number of forest land, grassland, and unused land were remained basically stable under the natural development scenario. The number of cultivated land types was continued to decrease, whereas, there was an increase in the number of construction land and water areas. A wider distribution of forest and grassland was found to significant promote the number of waters around Bohai Sea under the priority development scenario of carbon sequestration, compared with the natural one. Furthermore, the scope of outward expansion shared the central cities of Shijiazhuang, Tangshan, Baoding City, whereas, the other big cities were shrunk slightly in space, indicating the intensive effect of construction land. The net carbon emissions of land use in 2030 and 2060 were 67.42% and 38.16% of those in 2020, respectively, under the natural development scenario. The direct carbon emissions from land use in 2030 and 2060 increased by 1.13% and 2.99%, respectively, under the priority development scenario of carbon increase. Alternatively, the indirect carbon emissions from land use in 2030 and 2060 decreased by 4.55% and 10.40%, respectively, under the priority development scenario of carbon emission reduction. The priority net carbon emissions of carbon emission reduction decreased by 4.64% and 10.85%, respectively, compared with the natural development scenario. Among the three scenarios, the priority scenario of carbon reduction presented the least net carbon emission from land use. The finding can also provide a strong reference to analyze evolution patterns of carbon emission for the carbon neutral target.