Land use change on the surface area and the influence on carbon

China has diversified landforms, the three-dimensional space area check is more accurate to help determine China's land use change and the caused carbon variations. This study explored a new method to check China's surface area and examine the terrestrial carbon changes for the period of 2000-2020. The results show that China's surface area increased by 13.9% compared with the planar area, with the increased area measuring 133 x 104 km2. The south and the west, especially the southwest, usually have a high area increasing rate. Woodland has the highest area increasing rate for all the provinces. 10% of the land had its land use type changed. Cropland, grassland and unused show total land area decrease, woodland, water, and impervious all increased. The mean increasing rate of land transfer on surface area varied between 1.39% and 38.84%. The total amount of land use-type change caused carbon loss reached-5907.44 x 104 t, of -3168.97 x 104 t from vegetation storage loss,-2738.77 x 104 t from NPP and water. There were only seven provinces show carbon increase, which were more located in the west. Per unit of woodland loss will cause higher carbon release than other land use types. Land use control need to be further strengthened, especially for the protection of woodland at mountain regions.

Automated summary

China's diversified landforms and the use of three-dimensional space area calculation have provided accurate information on China's land use change and carbon variations. This study introduced a new method to examine China's surface area and analyze the changes in terrestrial carbon from 2000 to 2020. The findings indicate a 13.9% increase in China's surface area compared to the planar area, with a total increase of 133 x 104 km2. The southwest region had the highest rate of area increase, particularly in woodland. The study also revealed a significant carbon loss due to land use change, with woodland experiencing the highest carbon release compared to other land types. The protection of woodland in mountainous regions requires further attention.