[Evaluating the Impacts of Urbanization on Terrestrial Carbon Stocks under Shared Socioeconomic Pathways in Guangdong Province].

Urbanization is a vital factor inducing the loss of terrestrial carbon stocks， and evaluating the impacts of urbanization on terrestrial carbon stocks under shared socioeconomic pathways can provide decision-making references for achieving the dual carbon goals and selecting low-carbon urban development models. In this study， terrestrial carbon stock loss resulting from urbanization and the spatiotemporal evolution of urbanization in Guangdong Province during 2020 to 2050 were systematically assessed under the shared socioeconomic pathways scenario framework. The results show that most of the newly added urban area occurs in western Guangdong and the Pearl River Delta， including Zhanjiang， Maoming， Guangzhou and Foshan. Urbanization stabilizes in 2047 or 2048 under all SSP scenarios except SSP1， under which urbanization ceases to expand by 2039. Secondly， the loss of terrestrial carbon stocks （measured by C） resulting from urban expansion in Guangdong ranges from approximately 2.60 to 4.43 Tg under the five typical SSPs scenarios. Among all the SSPs scenarios， the slowest urbanization rate and minimum loss of terrestrial carbon stocks occurs under SSP1， while the largest newly added urban area and the maximum loss of terrestrial carbon stocks occurs under SSP5. Thirdly， cropland is the primary land cover type encroached upon by urban expansion under all of the SSP scenarios， accounting for approximately 85% of the total newly added urban built-up area. Water body， shrubland， forest， and others account for about 9%， 4%， 1%， and less than 1%， respectively， of the other land cover types transformed to newly added urban area. Correspondingly， the loss of carbon stocked in cropland contributes about 90% of the total carbon stock loss induced by urbanization. Shrubland and forest share the remaining 10% carbon stock loss. Finally， soil carbon stock， which accounts for more than 98% of the total carbon loss， is the main source of the total carbon stock loss resulting from urbanization.