Distribution, sources and influencing factors of heavy metals in the Ledong Sea, South China Sea.

The Ledong Sea Area is located on the southwest side of Hainan Island. In recent years, with the development of industrialization and urbanization, the problem of heavy metals in marine sediments has gradually become a global problem, and research on this topic is of great significance for nearshore environmental protection and coastal management. This paper analysed the heavy metal content of 97 surface sediments in the Ledong Sea, indicating unpolluted to moderately polluted and low to moderate risk.

Sedimentary records of environmental evolution in Dongzhai Port mangrove swamps (South China) over the last hundred years: Insights from corrections of grain-size effects.

Mangrove sediments play a vital role in the biogeochemical processes of elements by behaving as both sources and/or sink for nutrients and trace metals. Under the combined impacts of grain-size effects and human activities, it is difficult to accurately assess the sources and degree of pollutants. For this purpose, two cores were collected from a mangrove swamps of Dongzhai Port (South China) and analyzed for temporal distributions of grain size, nutrients, major and trace elements, and Pb activities.

Quantitative evaluation of impacts of the steadiness and duration of urban surface wind patterns on air quality.

The complexity and heterogeneity of urban land surfaces result in inconsistencies in near-surface winds, which in turn influence the diffusion and dispersion of air pollutants. In this study, we classified urban surface wind fields, quantified their steadiness, duration, and influence on air quality using hourly wind observations from 50 meteorological stations, as well as hourly PM and NO concentrations from 18 monitoring stations during 2017-2018 in Shenzhen, a mega city in southern China. We found that the K-means clustering technique was reliable for distinguishing surface wind patterns within the city.

Marine heatwaves impair the thermal refugia potential of marginal reefs in the northern South China Sea.

Frequent marine heatwaves (MHWs), concurrent with climate warming, threaten global low-latitude, pristine coral reefs, leading to growing interest in identifying marginal coral reefs (relatively high-latitude and/or turbid reef environments) that can serve as thermal refugia from mass coral bleaching. However, the thermal refugia potential of marginal reefs remains controversial. We evaluated the thermal refugia potential of inshore reefs in the northern South China Sea (nSCS), a globally typical marginal reef system, by characterizing the long-term trend of MHW intensity and frequency and assessing thermal stress during a mass bleaching event in summer 2020.