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Urban regeneration (UR) has been a leading concern in urban studies globally. China's rapid urbanization has undergone profound urban decay and social contestation, for which UR has emerged as a viable solution. However, UR is not without its drawbacks. It has caused emerging spatial and planning problems; however, few studies have explored the characteristics and issues of UR from the view of spatial analytics on the city scale. This study aims to depict the distribution characteristics of UR projects in Chinese cities and to reveal whether it meets the requirements of urban development from the planning perspective. The nearest neighbor index and its hierarchical clustering, as well as kernel density estimation are used in conjunction to investigate the spatial distribution characteristics; and the relationship between project distribution and each urban development indicator is explored using mixed spatial characteristics analyses, such as buffer analysis, space syntax, and heat mapping. Considering Shenzhen as the empirical study city, this research is based on all officially released data of implemented UR projects between 2010 and 2021. The findings imply that the UR projects in Shenzhen are mostly located in areas with higher economic development levels and accessibility with areas witnessing industrial restructuring and severe urban decay being prone to be designated for UR initiatives. The spatial distribution characteristics disclose the challenges inherent in the mix of top-down and market-driven UR approaches as well as the dilemma of the center-periphery pattern in UR implementation. Furthermore, the contradiction between the growing population and limited land resources as well as the barriers to industrial clustering formation are also revealed. This study enriches the methodological framework for spatial and visualization studies of urban regeneration in worldwide cities and sheds light on how to promote UR in regard to urban sustainability with ramifications for future urban development in other Chinese cities. [ABSTRACT FROM AUTHOR]

China's investments, financial incentives and deductions in terms of ecological conservation are based at the county level. Therefore, the monitoring and assessment of the effects of ecological conservation at the county level is important to provide a scientific basis for the assessment of the ecological and environmental quality at the county scale. This paper quantitatively estimated the dynamics of high-quality ecosystems and vegetation coverage over the past 15 years, and their relationships with the number of ecological conservation programs at the county level were analyzed. Then, the effects of ecological conservation measures on ecological changes at the county level and their regional suitability were assessed and discussed. The results showed that counties with a percentage of high-quality ecosystems greater than 50% were primarily distributed in northeastern China, southern subtropical China and the southeastern Qinghai-Tibet Plateau, and those with a percentage lower than 20% were mostly distributed in northwestern China, the southwestern karst region and the North China Plain. In recent decades, ecological conservation has focused on ecologically fragile regions; more than five ecological conservation programs have been implemented in most counties of the Three River Source Region in Qinghai Province, southeastern Tibet, western Sichuan, the Qilian Mountains, southern Xinjiang and other western regions, while only one or zero have been implemented in the eastern coastal area of China. Over the past 15 years, the proportional area of high-quality ecosystems has increased in approximately 53% of counties. The vegetation coverage of counties in the Loess Plateau, Huang-Huai-Hai Plain, Beijing-Tianjin-Hebei (Jing-Jin-Ji), Sichuan-Guizhou-Chongqing, and Guangdong-Guangxi provincial-level areas has increased significantly. However, it decreased in northern Xinjiang, central Tibet, central and eastern Inner Mongolia, the Yangtze River Delta and other regions. The relationships between the numbers of ecological conservation programs and the indicators of ecosystem restoration response, such as high-quality ecosystem and vegetation coverage, do not show positive correlations. These results suggest that ecological conservation programs should be planned and implemented according to the distribution patterns of high-quality ecosystems and that restoration measures such as afforestation should follow natural principles and regional differentiation under the background of climate change. [ABSTRACT FROM AUTHOR]

Due to the rapid urbanization in China, urban expansion has gradually shifted from large cities to small cities, causing spatiotemporal changes in the urban thermal environment. The differential thermal environmental characteristics of 334 cities at different hierarchy caused by urbanization are investigated in this study. Then, the spatiotemporal changes of land surface temperature (LST), albedo, and emissivity among urban areas and their surrounding buffer areas are analyzed during 2000–2015. We found that the urban warming effect is usually prominent in the daytime, with an obvious seasonal differentiation between 0.32 °C[0.27,0.38] in summer and -0.14 °C[-0.20,-0.07] in winter. The nighttime warming effect during summer resembles that in winter, in the range 0.23–0.25 °C. In addition, the number of cities with intensifying trends of the warming effect in summer daytime account for 50% of the total cities, but only 9% in winter nighttime, 23% in summer nighttime, and 25% in winter daytime. Large cities usually have obvious warming effects compared with small cities. But the highest warming effect is found in megacities during the daytime and in medium cities during the nighttime. In southern subtropical cities, the warming of urban zones is high in the daytime and low in the nighttime, while it is opposite in arid and semiarid regions, especially in winter. The negative correlations between the difference of surface albedo (emissivity) and LST in megacities and metropolitan areas emphasize that nighttime warming primarily results from radiation absorption and release affected by urbanization. This study may advance the understanding of the heterogeneity in the warming effects of different cities in China and support policy formulation and regulation to adapt to urban warming. [ABSTRACT FROM AUTHOR]

Blue Carbon (BC) strategy refers to the approaches that mitigate and adapt to climate change through the conservation and restoration of seagrass, saltmarsh and mangrove ecosystems and, in some BC programs, also through the expansion of seaweed aquaculture. The major losses of coastal habitats in combination with the commitments of China under the Paris Agreement provide unique opportunity and necessity to develop a strong Chinese BC program. Here, we (1) characterize China's BC habitats, examine their changes since 1950 along with the drivers of changes; (2) consider the expansion of seaweed aquaculture and how this may be managed to become an emerging BC resource in China, along with the engineering solutions required to enhance its potential; and (3) provide the rationale and elements for BC program in China. We find China currently has 1326–2149 km2 wild and 2–15 km2 created mangrove, saltmarsh and seagrass habitats, while 9236–10059 km2 (77–87%) has been lost since 1950, mainly due to land reclamation. The current area of farmed seaweed habitat is 1252–1265 km2, which is close to the area of wild mangrove, saltmarsh and seagrass habitats. We conclude that BC strategies have potentials yet to be fully developed in China, particularly through climate change adaptation benefits such as coastal protection and eco-environmental co-benefits of seaweed farming such as habitat creation for fish and other biota, alleviation of eutrophication, hypoxia and acidification, and the generation of direct and value added products with lower environmental impact relative to land-based production. On this basis, we provide a roadmap for BC strategies adjusted to the unique characteristics and capacities of China. Blue Carbon (BC) plays important roles in climate change mitigation/adaptation. In this paper, we 1) characterize China's BC habitats and examine their changes since 1950 along with the drivers of changes; 2) consider the expansion of seaweed aquaculture and how this may be managed to become an emerging BC resource in China, along with the engineering solutions required to enhance its potential; 3) provide the rationale and elements for BC program in China; and 4) draw a roadmap for BC strategies adjusted to the unique characteristics and capacities of China.Porphyra farm in Dongtou, Wenzhou city, Zhejiang province, China. Image 1 • China's Blue Carbon (BC) habitats, changes and the drivers of changes since 1950. • Potential BC resources, seaweed aquaculture expansion with engineering solutions. • BC Benefits for climate adaptation and co-benefits for environment and economy. • Great potential of China's BC strategies through climate change adaptation benefits. • A roadmap for BC strategies adjusted to the China's characteristics and capacities. [ABSTRACT FROM AUTHOR]