Spatial Heterogeneity and Attribution Analysis of Urban Thermal Comfort in China from 2000 to 2020

Estimating the Amount of the Wild Artemisia annua in China Based on the MaxEnt Model and Spatio-Temporal Kriging Interpolation

In order to determine the distribution area and amount of Artemisia annua Linn. (A. annua) in China, this study estimated the current amount of A. annua specimens based on the field survey sample data obtained from the Fourth National Census of Chinese Medicinal Resources. The amount was calculated using the maximum entropy model (MaxEnt model) and spatio-temporal kriging interpolation. The influencing factors affecting spatial variations in the amount were studied using geographic probes. The results indicated that the amount of A. annua in China was about 700 billion in 2019. A. annua was mainly distributed in the circular coastal belt of Shandong Peninsula, central Hebei, Tianjin, western Liaoning, and along the Yangtze River and in the middle and lower reaches of Jiangsu, Anhui, and the northern Chongqing provinces. The main factors affecting the amount are the precipitation in the wettest and the warmest seasons, the average annual precipitation, and the average temperature in the coldest and the driest seasons. The results show that the amount of A. annua is strongly influenced by precipitation and temperature.

Impact of digital economy on ecological resilience of resource-based cities: spatial spillover and mechanism

Resource-based cities, which are widely distributed in China, contribute significantly to China's sustainable development. The digital economy and the construction of ecological civilization are central issues in the sustainable development of resource-based cities, and it is necessary to analyze the impact of the digital economy on the ecological resilience of resource-based cities. Thus, this paper measures ecological resilience of 117 resource-based cities from 2011 to 2020 using the entropy weight TOPSIS (technique for order preference by similarity to ideal solution; see Table 1 for a list of acronyms) method and empirically investigates the impact and mechanism of digital economy on ecological resilience using the spatial Durbin model (SDM) and intermediary effect model. The results show that the ecological resilience of resource-based cities has a certain upward trend, with a stepwise distribution pattern from east to west. There is a significant positive correlation between ecological resilience of resource-based cities, showing the phenomenon of club convergence which is primarily dominated by high-high (H-H) and low-low (L-L). The digital economy has a significant spatial spillover effect, which promotes ecological resilience of resource-based cities in the local and adjacent regions. A mechanism analysis reveals that technological innovation and industrial structure are mediators between digital economy and ecological resilience of resource-based cities, with significant heterogeneity in region and growth cycle. Among them, the intermediary role of technological innovation is stronger. Following the above findings, this paper proposes policy suggestions related to digital economy evolution and ecological resilience enhancement. This paper further enriches the literature on the ecological resilience and provides a theoretical basis for government policy-making.

Temporal and spatial effects of large airport construction and operation on the local thermal environment

New construction has resulted in impervious surfaces increasingly replacing natural landscapes, altering surface radiation, thermal properties, and humidity in urban areas. Based on Landsat-8 data, the temporal and spatial impacts of the construction of Dalian Jinzhouwan Airport and Beijing Daxing Airport on the thermal environment were studied. The local thermal gradient (LTG) of the airport before and after construction is compared. The results showed that after the completion of the airport, the LTG value of Daxing Airport increased by 0.033 and that of Jinzhou Bay Airport increased by 0.009. After the airport operation, LTG values increase again. Daxing Airport added another 0.053, and Jinzhou Bay Airport added another 0.127. Two land classification models (land use type, LUT; local climate zone, LCZ) were used to explore the relationship between land use type and LTG. The results show that the increase of alloy buildings after the completion of the airport has a great influence on the thermal environment of the two study areas. The operation of airports will further enhance this effect. Our study can provide a reference for the influence of large-scale traffic construction on the urban thermal environment.