Spatiotemporal Variation Assessment and Improved Prediction Of Cyanobacteria Blooms in Lakes Using Improved Machine Learning Model Based on Multivariate Data.

Cyanobacterial blooms in shallow lakes pose a significant threat to aquatic ecosystems and public health worldwide, highlighting the urgent need for advanced predictive methodologies. As impounded lakes along the Eastern Route of the South-to-North Water Diversion Project, Lakes Hongze and Luoma play a key role in water resource management, making the prediction of cyanobacterial blooms in these lakes particularly important. To address this, satellite remote sensing data were utilized to analyze the spatiotemporal dynamics of cyanobacterial blooms in these lakes.

Dynamic changes of leachates of aged plastic debris under different suspended sand concentrations and their toxicity.

Plastic pollution in aquatic environments poses significant ecological risks, particularly through released leachates. While traditional or non-biodegradable plastics (non-BPs) are well-studied, biodegradable plastics (BPs) have emerged as alternatives that are designed to degrade more rapidly within the environment. However, research on the ecological risks of the leachates from aged BPs in aquatic environments is scarce.

Effects of reduced flow gradient on benthic biofilm communities' ecological network and community assembly.

The intensification of human activities has led to flow reduction and cut-off in most global rivers, seriously affecting riverine organisms and the biogeochemical processes. As key indicators of river ecosystems' structure and function, benthic biofilms play a critical role in driving primary production and material cycling in rivers. This research aimed to investigate the characteristics of microbial communities' complexity and stability during river flow reduction.

Distinct effects of flow intermittency on the benthic microbial diversity and their denitrification on different substrates.

Global climate change has significantly increased the duration of droughts in intermittent rivers, impacting benthic microbial-mediated biogeochemical processes. However, the response mechanisms of biofilms on different substrate types to alternating dry and wet conditions and their related ecosystem functions remain poorly understood. This study uses high-throughput sequencing and enzyme assays to investigate the impact of gradient drought stress on microbial diversity and functional changes of biofilm communities inhabiting on gravel, cobblestone, and sediment.

Long-term performance and mechanism of in-situ biogenetic sulfidated zero-valent iron for enhanced nitrate reduction.

The biogenetic sulfidation of zero-valent iron (BS-ZVI) by sulfate-reducing bacteria (SRB) has been demonstrated to enhance the reactivity of ZVI. However, long-term performance of BS-ZVI and related mechanism were still unknown. Therefore, columns containing sponge iron and SRB are built to prepare BS-ZVI in-situ and study its long-term performance.

The selective occurrence of ripening effect makes the cotransport of various sized nanoplastics in seawater-saturated and freshwater-saturated porous media significantly different.

We explored the coadsorption and cotransport (single, binary, and ternary systems) of varying sized (50, 200, and 500 nm) Polymethylmethacrylate (PMMA) nanoplastics (NPs) with different concentration ratios in freshwater-saturated and seawater-saturated porous media. It was found that ripening effect occurred selectively, with ripening more likely to occur in seawater relative to freshwater, resulting in significantly different cotransport and coadsorption of varying sized NPs in freshwater-saturated and seawater-saturated porous media. In freshwater, there was no obvious ripening effect happening.

Intensified river salinization alters nitrogen-cycling microbial communities in arid and semi-arid regions of China.

Freshwater salinization is receiving increasing global attention due to its profound influence on nitrogen cycling in aquatic ecosystems and the accessibility of water resources. However, a comprehensive understanding of the changes in river salinization and the impacts of salinity on nitrogen cycling in arid and semi-arid regions of China is currently lacking. A meta-analysis was first conducted based on previous investigations and found an intensification in river salinization that altered hydrochemical characteristics.

Climate warming promotes collateral antibiotic resistance development in cyanobacteria.

Both cyanobacterial blooms and antibiotic resistance have aggravated worldwide and posed a great threat to public health in recent years. As a significant source and reservoir of water environmental resistome, cyanobacteria exhibit confusing discrepancy between their reduced susceptibility and their chronic exposure to antibiotic mixtures at sub-inhibitory concentrations. How the increasing temperature affects the adaptive evolution of cyanobacteria-associated antibiotic resistance in response to low-level antibiotic combinations under climate change remains unclear.

Statuses, shortcomings, and outlooks in studying the fate of nanoplastics and engineered nanoparticles in porous media respectively and borrowable sections from engineered nanoparticles for nanoplastics.

This review discussed the research statuses, shortcomings, and outlooks for the fate of nanoplastics (NPs) and engineered nanoparticles (ENPs) in porous media and borrowable sections from ENPs for NPs. Firstly, the most important section was that we reviewed the research statuses on the fate of NPs in porous media and the main influencing factors, and explained the influencing mechanisms. Secondly, in order to give NPs a reference of research ideas and influence mechanisms, we also reviewed the research statuses on the fate of ENPs in porous media and the factors and mechanisms influencing the fate.

Spatiotemporal dynamics and modeling of thiacloprid in paddy multimedia systems with the effect of wetting-drying cycles.

The widespread presence of thiacloprid (THI), a neonicotinoid, raises concerns for human health and the aquatic environment due to its persistence, toxicity, and bioaccumulation. The fate of THI in paddy multimedia systems is mainly governed by irrigation practices, but the potential impacts remain poorly documented. This study investigated the effects of water management practices on THI spatiotemporal dynamics in paddy multimedia systems by combining soil column experiments and a non-steady-state multimedia model.

Characterization of the dynamic aging and leached dissolved organic carbon from biodegradable and conventional plastics under photooxidation.

Biodegradable plastics have been regarded as promising candidates in the struggle against plastic pollution. However, the aging and dynamic leaching process of biodegradable and conventional plastics under photooxidation is still unclear. Herein, three types of non-biodegradable plastics (polypropylene, polyethylene, and polyethylene terephthalate), and two types of biodegradable plastics (polylactic acid and cornstarch-based plastics) were treated with 21 days of photooxidation followed by 13 days of dark conditions.

Transformation of Biofilm to Carbon Sinks after Prolonged Droughts Linked with Algal Biodiversity Change.

Global climate change significantly increased the duration of droughts in intermittent rivers, impacting benthic microbial-mediated biogeochemical processes. However, the impact of prolonged droughts on the carbon contribution of intermittent rivers remains poorly understood. In this study, we investigated the potential effects of varying drought gradients (ranging from 20 to 130 days) on benthic biofilms community structure (algae, bacteria, and fungi) and their carbon metabolism functions (ecosystem metabolism and carbon dioxide (CO) emission fluxes) using mesocosm experiments.

Optimal allocation of agricultural water and land resources integrated with virtual water trade: A perspective on spatial virtual water coordination.

Agricultural production consumes the majority of global freshwater resources. The worsening water scarcity has imposed significant stress on agricultural production when regions seek food self-sufficiency. To seek optimal allocation of spatial agricultural water and land resources in each water function zone of the objective region, a multi-objective optimization model was developed to tackle the trade-offs between the water-saving objective and the economic benefit objective considering virtual water trade (VWT).

Effects of released organic components of solid carbon sources on denitrification performance and the related mechanism.

Here, a hybrid scaffold of polyvinyl alcohol/sodium alginate (PVA/SA) was used to prepare solid carbon sources (SCSs) for treating low carbon/nitrogen wastewater. The four SCSs were divided into two groups, biodegradable polymers group (including polyvinyl alcohol-sodium alginate (PS) and PS-PHBV (PP), and blended SCSs (PS-PHBV-wood chips (PPW) and PS-PHBV-wheat straw (PPS)). After the leaching experiments, no changes occurred in elemental composition and functional groups of the SCSs, and the released dissolved organic matter showed a lower degree of humification and higher content of labile molecules in the blended SCSs groups using EEM and FT-ICR-MS.

Antibiotics can alter the bacterial extracellular polymeric substances and surface properties affecting the cotransport of bacteria and antibiotics in porous media.

Currently, studies on the environmental impact of antibiotics have focused on toxicity and resistance genes, and gaps exist in research on the effects of antibiotics entering the environment on bacterial surface properties and the synergistic transport of antibiotics and bacteria in porous media. To fill the gaps, we investigated the interactions between bacteria and antibiotics in synergistic transport in saturated porous media and the effects of media particle size, flow rate, and ionic concentration on this synergistic transport. This study revealed that although synergistic transport was complex, the mechanism of action was clear.

Surface modification significantly changed the effects of nano-polystyrene on sediment microbial communities and nitrogen metabolism.

Nanoplastics are ubiquitous in the natural environment, and their ecological risks have received considerable attention. Surface modification is common for nanoplastics and an essential factor affecting their toxicity. However, studies on the potential effects of nanoplastics and their surface-modified forms on functional communities in aquatic systems are still scarce.

A quaternary ammonium salt grafted tannin-based flocculant boosts the conjugative transfer of plasmid-born antibiotic resistance genes: The nonnegligible side of their flocculation-sterilization properties.

This study developed dual-function tannin-based flocculants, namely tannin-graft-acrylamide-diallyl dimethyl ammonium chloride (TGCC-A/TGCC-C), endowed with enhanced flocculation-sterilization properties. The impacts of these flocculants on proliferation and transformation of antibiotic resistance genes (ARGs) among bacteria during the flocculation-deposition process were examined. TGCC-A/TGCC-C exhibited remarkable flocculation capacities towards both Escherichia coli and Staphylococcus aureus, encompassing a logarithmic range of initial cell density (10-10 CFU/mL) and a broad pH spectrum (pH 2-11).

Combined effects of bacteria and antibiotics on surface properties and transport of nanoplastics in porous media.

Currently, research on the individual effects of bacteria and antibiotics on the transport of nanoplastics (NPs) in porous media is in its infancy, while research on their combined effect is absent. It is well known that bacteria and antibiotics also interact with each other, so this synergistic transport of bacteria, antibiotics, and NPs in porous media must be very interesting. For exploring this aspect, we investigated the individual and combined effects of bacteria and antibiotics on the transport of polystyrene NPs (PS-NPs) in saturated porous media.

Influence of humate on the degradation of chloramphenicol by sulfidated ferrihydrite under dynamic anoxic/oxic environments: A combined DFT calculation and experimental study.

Sulfidation of ferrihydrite is known to affect the degradation of contaminants, but little was known about the role of natural organic matter (NOM) in antibiotics degradation by sufidated ferrihydrite under redox-dynamic conditions. Here, a typical antibiotic (i.e.

Long-term effects of Ag NPs on denitrification in sediment: Importance of Ag NPs exposure ways in aquatic ecosystems.

The widespread use of silver nanoparticles (Ag NPs) inevitably leads to their increasing release into aquatic systems, with studies indicating that the mode of Ag NPs entry into water significantly affects their toxicity and ecological risks. However, there is a lack of research on the impact of different exposure ways of Ag NPs on functional bacteria in sediment. This study investigates the long-term influence of Ag NPs on denitrification process in sediments by comparing denitrifies responses to single (pulse injection of 10 mg/L) and repetitive (1 mg/L × 10 times) Ag NPs treatments over 60-day incubation.

Transport of polystyrene nanoplastics in porous media: Combined effects of two co-existing substances.

Both surfactants and natural organic matters (NOMs) are substances commonly found in aqueous environments, and their effects on the transport of nanoplastics that is gradually gaining widespread attention in porous media are currently in their infancy, while their combined effects are absent. We investigated innovatively the combined effect of surfactants and NOMs on the transport of polystyrene nanoplastics (PS-NPs) in saturated porous media. Adsorption tests of surfactants and NOMs onto PS-NPs, adsorption tests of PS-NPs onto quartz sand, and transport tests of PS-NPs in saturated quartz sand were conducted.

Influence of natural organic matters on fate of polystyrene nanoplastics in porous media.

Natural organic matters (NOMs) are widely present in aqueous environments. The effect of NOMs on the fate of nanoplastics that are gradually receiving widespread attention in porous media needs to be noticed, but relevant research is lacking. To fill this gap, the present study focused on elucidating the influence of NOMs and metal cations with varying concentrations upon the transport, long-term release, and particle fracture of polystyrene nanoplastics (PS-NPs) in saturated porous media.