High summer background O levels in the desert of northwest China.

Generally speaking, the precursors of ozone (O), nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions, and thus O concentrations are relatively low. However, high summer background concentrations of about 100 µg/m or 60 ppb were found in the Alxa Desert in the highland of northwest China based on continuous summer observations from 2019 to 2021, which was higher than the most of natural background areas or clean areas in world for summer O background concentrations. The high O background concentrations were related to surface features and altitude.

Quantitative analysis of influencing factors to aerosol pH and its responses to PM and O pollution in a coastal city.

Aerosol acidity (pH) plays an important role in the multiphase chemical processes of atmospheric particles. In this study, we demonstrated the seasonal trends of aerosol pH calculated with the ISORROPIA-II model in a coastal city of southeast China. We performed quantitative analysis on the various influencing factors on aerosol pH, and explored the responses of aerosol pH to different PM and O pollution levels.

Development of an automated photolysis rates prediction system based on machine learning.

Based on observed meteorological elements, photolysis rates (J-values) and pollutant concentrations, an automated J-values predicting system by machine learning (J-ML) has been developed to reproduce and predict the J-values of OD, NO, HONO, HO, HCHO, and NO, which are the crucial values for the prediction of the atmospheric oxidation capacity (AOC) and secondary pollutant concentrations such as ozone (O), secondary organic aerosols (SOA). The J-ML can self-select the optimal "Model + Hyperparameters" without human interference. The evaluated results showed that the J-ML had a good performance to reproduce the J-values where most of the correlation (R) coefficients exceed 0.

Study of spatiotemporal variation and annual emission of CH in Shaoxing Yangtze River Delta, China, Using a portable CH detector on the UAV.

Methane (CH) is the second greenhouse gas and has a profound impact on global climate change due to its high global warming potential and concentration. By 2022, the CH concentration was approximately 1.9 ppm, which was 264% of the pre-industrial level.

Interpreting hourly mass concentrations of PM chemical components with an optimal deep-learning model.

PM constitutes a complex and diverse mixture that significantly impacts the environment, human health, and climate change. However, existing observation and numerical simulation techniques have limitations, such as a lack of data, high acquisition costs, and multiple uncertainties. These limitations hinder the acquisition of comprehensive information on PM chemical composition and effectively implement refined air pollution protection and control strategies.

The source and dissemination of ARGs in pristine environments: Elucidating the role of migratory birds in the Arctic.

Antibiotic resistance genes (ARGs) are a class of emerging contaminants that significantly threaten public health. In this work, the profiles of ARGs and microbial communities in the soil, sediment, migratory bird, and local deer fecal samples collected from the Arctic were characterized using a metagenomic approach. The results retrieved the baseline profiles of ARGs and identified the role of migratory birds in disseminating ARGs in the Arctic.

Pollution Characteristics and Ecological Impact of Screening Analysis of Fishing Port Sediments from Dalian, North China.

Environmental pollution from synthetic chemical mixtures has significant adverse impacts on marine ecosystems. However, identifying the main constituents of chemical mixtures that pose ecological threats is challenging due to the necessity of an integrated workflow for comprehensive identification and toxicological prioritization of pollutants. Here, an all-in-one mass spectrometric strategy integrating target, suspect, and nontarget analysis was used to investigate organic pollutants of concern in fishing port sediments, with 355 pollutants (32 from target analysis, 118 from suspect screening and 205 from nontarget analysis) identified in 11 categories.

Seasonal and long-term variations of nutrients in Liaodong Bay, China: Influencing factors and ecological effects.

Nutrients are essential for marine primary productivity and have a critical role in maintaining the structure and function of marginal. Variations in nutrient levels in sea ecosystems can influence ecological disturbances significantly. The Liaodong Bay (LDB) is a semi-enclosed marginal sea in northern China.

Occurrence status, source analysis and risk assessment of polycyclic aromatic hydrocarbons in intertidal surface sediments of typical mangrove wetlands in Guangxi Province, China.

This study investigated the occurrence status, sources, and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in sediments from three typical mangrove areas in Guangxi Province, China. Results showed that the PAH content in the three studied regions ranged from 39.76 ng·g to 164.

[Predictive Model for O in Shanghai Based on the KZ Filtering Technique and LSTM].

In this study, a Kolmogorov-Zurbenko （KZ） filter was proposed to decompose the original ozone （O） sequence to improve the accuracy of ozone long-term series prediction and select relevant meteorological features. Furthermore, the enhanced maximal minimal redundancy （mRMR） feature selection technique was combined with the support vector regression （SVR） approach to select the most illuminating meteorological features. Subsequently, from May to August 2023, during high ozone concentration periods, a long short-term memory network （LSTM） was utilized to assess and predict high ozone concentration periods at the monitoring stations of Jingan （urban area）, Pudong-Chuansha （suburban area）, and Dianshan Lake （suburban area） in Shanghai.

[Analysis of Ozone Pollution and Precursor Control Strategies in the Pearl River Delta During Summer and Autumn Transition Season].

To analyze the causes of ozone pollution in the Pearl River Delta （PRD） Region during the summer and autumn transition seasons, a case study was carried out in Guangzhou, which is located in the center of the PRD Region, to analyze the ozone photochemical production and destruction pathways as well as emission reduction scenarios using a box model based on comprehensive observation. The results showed that the stagnant meteorological conditions and high temperature during the observation period were suitable for the photochemical production of ozone, which led to widespread and prolonged ozone pollution. Aromatic hydrocarbons （AHs） contributed the most to the ozone formation potential （OFP）, and /-xylene, toluene, and -xylene were the major three VOC species contributing to the OFP.

Spatiotemporal Analysis of Complex Emission Dynamics in Port Areas Using High-Density Air Sensor Network.

Cargo terminals, as pivotal hubs of mechanical activities, maritime shipping, and land transportation, are significant sources of air pollutants, exhibiting considerable spatiotemporal heterogeneity due to the complex and irregular nature of emissions. This study employed a high-density air sensor network with 17 sites across four functional zones in two Shanghai cargo terminals to monitor NO and NO concentrations with high spatiotemporal resolution post sensor data validation against regulatory monitoring stations. Notably, NO and NO concentrations within the terminal surged during the night, peaking at 06:00 h, likely due to local regulations on heavy-duty diesel trucks.

Phylogenomic Analysis of Dichrocephala benthamii and Comparative Analysis within Tribe Astereae (Asteraceae).

Dichrocephala benthamii C. B. Clarke has long been used as traditional Chinese medicine.

A comparative study on contamination profiles of liquid crystal monomers (LCMs) between outdoor and indoor dusts, and the assessment of health risk of human exposure.

Liquid crystal monomers (LCMs) are ubiquitous in various environmental samples, which has led to increasing concerns regarding their potential health risks to humans and wildlife. However, the comparison of the contamination patterns of LCMs between indoor and outdoor environments has rarely been studied. In this study, 35 LCMs were investigated in n = 55 dust samples collected from indoor (n = 20) and outdoor (n = 35) spaces in Yulin, Northwest China.

Quantitatively unveiling the role of coastal wetlands in regulating eutrophication and enhancing water environmental capacity.

Human activities have intensified the global challenge of coastal eutrophication. Recently, water resource managers have encountered difficulties in formulating precise pollutant reduction strategies to mitigate coastal eutrophication. Despite the recognized importance of coastal wetlands and pollution sources in influencing coastal nutrient levels, accurately quantifying their impact remains difficult.

Education and technological innovation in mitigating CO emissions and fostering green economic growth in China: Marginal effects and policy threshold analyses.

This study makes a significant contribution to China's ambitious goals of achieving carbon dioxide (CO) neutrality and transitioning to green economic growth (GEG), and integrating the theoretical framework of the impact, population, affluence, and technology (IPAT) theory, with real-world application to reduce CO and promote GEG for sustainable development. Furthermore, the study examines the ongoing theoretical debate on whether an inverted U-shaped environmental Kuznets curve (EKC) exists between technological innovations (TI) in environment-related fields and CO emissions in China, using data from 1990 to 2020 and employing the threshold instrumental variable two-stage least-squares (Th-IV2SLS) model. The findings indicate that all the variables representing education contribute to reducing CO emissions.

In-situ online investigation of biogenic volatile organic compounds emissions from tropical rainforests in Hainan, China.

Biogenic volatile organic compounds (BVOCs) emitted by tropical plants represent a significant proportion of global emissions, but the in-situ BVOC measurements in tropical rainforests are extremely sparse. Herein, a vehicle-mounted mobile monitoring system was developed for in-situ online investigations of BVOC emissions from thirty representative tree species in the tropical rainforests of Hainan Island, southern China. The results showed that monoterpenes were the primary BVOCs emitted from most broadleaf trees.

Spatial heterogeneity of the integrated risks of urban heat stress and flooding strike.

Clarifying the spatial heterogeneity of the multiple climate-related risks has increasingly become a prerequisite for urban risk management and sustainability. As the datasets become more detailed in social attribute's representation at the fine scale within-city level, in contrast to those at a coarse region level, there is a continuous need to examine the spatial heterogeneity of integrated risk assessment. In this study, we applied the hazard-exposure-vulnerability framework to investigate the spatial variations of the integrations of urban heat stress and flooding strikes at the street block scale within Shenzhen, China.

Typical Marine Ecological Disasters in China Attributed to Marine Organisms and Their Significant Insights.

Owing to global climate change or the ever-more frequent human activities in the offshore areas, it is highly probable that an imbalance in the offshore ecosystem has been induced. However, the importance of maintaining and protecting marine ecosystems' balance cannot be overstated. In recent years, various marine disasters have occurred frequently, such as harmful algal blooms (green tides and red tides), storm surge disasters, wave disasters, sea ice disasters, and tsunami disasters.