Macrogenomic analysis of tolerance and degradation mechanisms of polycyclic aromatic hydrocarbon in carbon and nitrogen metabolic pathways and associated bacterial communities during endogenous partial denitrification.

The effective production of NO-N through endogenous partial denitrification (EPD) provides a promising perspective for the broader adoption and application of anaerobic ammonia oxidation. However, the accumulation of polycyclic aromatic hydrocarbons (PAHs) in the environment may worsen the operational challenges of the EPD system. This study evaluated the resilience of the EPD system to the toxic impacts of phenanthrene (PHE) and anthracene (ANT) through macrogenomic analysis.

Response of a simulated aquatic fungal community to nanoplastics exposure and functional consequence on leaf decomposition.

Nanoplastics pose a potential threat to a wide variety of aquatic organisms. Despite the awareness of this existing hazard, the impact of nanoplastics on natural fungal communities remains a research gap. In this study, five dominant fungi species, isolated from a stream ecosystem, were used to explore the effects of different nano-polystyrene (nano-PS) particles concentrations on a simulated fungal community.

Hourly emissions of air pollutants and greenhouse gases from open biomass burning in China during 2016-2020.

Open biomass burning (OBB) is a significant source of air pollutants and greenhouse gases that have contributed to air pollution episodes in China in recent years. An accurate emission inventory is critical for the precise control of OBB. Existing OBB emission datasets are commonly based on MODIS observations, and most only have a daily-scale temporal resolution.

Polystyrene size-dependent impacts on microbial decomposers and nutrient cycling in streams.

The particle size of plastic is one of the most important factors influencing its ecotoxicity, but we are unclear about the effect of polystyrene (PS) particle size on microbial decomposers and consequent nutrient cycling in streams. Here, using microcosm experiments, we assessed how three PS sizes (50 nm, 1 μm, and 20 μm) influenced the process and consequences of leaf litter decomposition. Under acute exposure to 1 μm and 20 μm PS, fungal biomass significantly decreased, but microbial biomass significantly increased, indicating compensations may work between fungi and other microbial decomposers.

Developing a model-ready highly resolved HONO emission inventory in Guangdong using domestic measured emission factors.

Nitrous acid (HONO) plays an important role in the budget of hydroxyl radical (OH) in the atmosphere. However, current chemical transport models (CTMs) typically underestimate ambient concentrations of HONO due to a dearth of high resolution primary HONO emission inventories. To address this issue, we have established a highly resolved bottom-up HONO emission inventory for CTMs in Guangdong province, utilizing the best available domestic measured emission factors and newly obtained activity data.

A meteorologically adjusted ensemble Kalman filter approach for inversing daily emissions: A case study in the Pearl River Delta, China.

The conventional Ensemble Kalman filter (EnKF), which is now widely used to calibrate emission inventories and to improve air quality simulations, is susceptible to simulation errors of meteorological inputs, making accurate updates of high temporal-resolution emission inventories challenging. In this study, we developed a novel meteorologically adjusted inversion method (MAEInv) based on the EnKF to improve daily emission estimations. The new method combines sensitivity analysis and bias correction to alleviate the inversion biases caused by errors of meteorological inputs.

Near-real-time estimation of hourly open biomass burning emissions in China using multiple satellite retrievals.

Open biomass burning (OBB) is an important source of air pollutants and greenhouse gases, but its dynamic emission estimation remains challenging. Existing OBB emission datasets normally provide daily estimates based upon Moderate Resolution Imaging Spectroradiometer (MODIS) retrievals but tend to underestimate the emissions due to the coarse spatial resolution and sparse observation frequency. In this study, we proposed a novel approach to improve OBB emission estimations by fusing multiple active fires detected by MODIS, Visible Infrared Imaging Radiometer onboard the Suomi National Polar-orbiting Partnership (VIIRS S-NPP) and Himawari-8.

Dual-carbon isotope constraints on source apportionment of black carbon in the megacity Guangzhou of the Pearl River Delta region, China for 2018 autumn season.

Black carbon (BC) aerosol negatively affects air quality and contributes to climate warming globally. However, little is known about the relative contributions of different source control measures to BC reduction owing to the lack of powerful source-diagnostic tools. We combine the fingerprints of dual-carbon isotope using an optimized Bayesian Markov chain Monte Carlo (MCMC) scheme and for the first time to study the key sources of BC in megacity Guangzhou of the Pearl River Delta (PRD) region, China in 2018 autumn season.

An updated model-ready emission inventory for Guangdong Province by incorporating big data and mapping onto multiple chemical mechanisms.

An accurate characterization of spatial-temporal emission patterns and speciation of volatile organic compounds (VOCs) for multiple chemical mechanisms is important to improving the air quality ensemble modeling. In this study, we developed a 2017-based high-resolution (3 km × 3 km) model-ready emission inventory for Guangdong Province (GD) by updating estimation methods, emission factors, activity data, and allocation profiles. In particular, a full-localized speciation profile dataset mapped to five chemical mechanisms was developed to promote the determination of VOC speciation, and two dynamic approaches based on big data were used to improve the estimation of ship emissions and open fire biomass burning (OFBB).

Identification of long-term evolution of ozone sensitivity to precursors based on two-dimensional mutual verification.

Tropospheric ozone pollution has been continuously worsening in China during the past decade. Identification of long-term evolution of ozone sensitivity to precursors is essential to evaluating the impact of emission reduction measures on ozone pollution. Traditional observation-based model and 3-d numerical model are not suitable for analyzing long-term variation of ozone sensitivity to precursors.

Regional discrepancies in spatiotemporal variations and driving forces of open crop residue burning emissions in China.

As a major source of secondary organic aerosol, open crop residue burning (OCB) emits a large number of trace gases and particulates to the atmosphere. Extensive OCB is detected during harvest seasons in most regions of China. Emissions from OCB have been widely investigated in China, but few studies have focused on regional discrepancies in spatiotemporal variations with a long timescale.

Refined 2013-based vehicle emission inventory and its spatial and temporal characteristics in Zhengzhou, China.

Vehicle emission is becoming one of the most important pollution sources because of the increase in vehicle population and activity in China. A more reasonable and complete vehicle emission inventory in Zhengzhou for the year 2013 was developed in this study. This inventory is suitable for local emission factors and vehicle kilometers of travel.