环境科学与技术最新文献

The extensive application of plastic products in daily human life has led to the accumulation of microplastics (MPs) in agricultural soil. However, little is known about the cross-generational toxicity of MPs on terrestrial invertebrates. In this study, two-generational Eisenia fetida was exposed to low-density polyethylene (LDPE, 0-5%, w/w) for 98 days to reveal the cross-generational toxicity and the underlying mechanisms. Results showed that LDPE-MPs not only perpetrated deleterious effects on the development, hatchability, and fecundity of the F0 generation but also stimulated the antioxidant defense activity, inhibited lipid peroxidation, and disordered neurotransmission in F1 generation individuals. The susceptibility of the epidermal-intestinal barrier to LDPE-MPs was dose-dependent. According to the transcriptomic analysis, the cross-generational earthworms confirmed significant perturbances in the cell cycle, neural activity-related pathways, and amino acid metabolism pathways (p < 0.05). Nevertheless, the metabolomic profile of F1 generation individuals exhibited significant hyperactive responses in glutathione metabolism and alanine, aspartate, and glutamate metabolism (p < 0.05). This study provides a comprehensive knowledge of LDPE-MPs toxicity on cross-generational earthworms and highlights the hyperactive responses in the antioxidant defense performance of the offsprings. Our findings also underscore the necessity for long-term investigations in assessing the adverse impacts of emerging pollutants.

Environmental contaminants pose a significant selection pressure across taxa, potentiating evolved resistance to chemicals. However, rapid evolution may alter molecular and physiological homeostasis leading to trade-offs. To elucidate molecular underpinnings of evolved chemical resistance, we compared liver gene expression and methylation profiles in polycyclic aromatic hydrocarbon (PAH)-adapted Atlantic killifish (Fundulus heteroclitus) in the Republic site (RP), Elizabeth River, Virginia with PAH-sensitive Kings Creek (KC) fish. We found 1607 differentially expressed and 2252 alternatively spliced genes between RP and KC, with highly enriched genes involving lipid and amino acid metabolism, respectively. While 308 genes had differentially methylated regions, only 13 of these genes were differentially expressed. The aryl hydrocarbon receptor 2b gene (ahr2b) was differentially methylated and expressed, as well as alternatively spliced signifying its critical role in mediating PAH tolerance. Notably, the intrapopulation coefficient of variation (CoV) was lower in 82% of 17,566 expressed genes in RP fish compared to KC fish. Among other pathways, these genes with low CoV were highly enriched in bioenergetic processes inferring reduced metabolic physiological variation as a population in RP fish. Altered metabolic gene expression and overall reduced gene expression variance in RP fish warrant further studies on fitness trade-offs including altered susceptibility to other stressors associated with rapid adaptation to anthropogenic pressures.

Urban greening (UG) affects local climate by altering surface energy balance, while long-term UG cooling potential, patterns, and contribution to curbing urban warming remain unclear. Here, we designed an novel statistical model to evaluate the cooling potential of UG (CPUG) and created the first CPUG map for China. By exploring the trends in observed and simulated urban surface temperatures (UST), we quantified the CPUG of 0.20 K over the past two decades, which slowed down the warming trend by 14.17% in Chinese cities. We found that the CPUG varied significantly between the urban core and sprawl areas. Specifically, the CPUG in the urban core was approximately 1.01 K, and it contributed to curbing urban warming by 56.08%, which was more than 7.2 times higher than in the sprawl areas, where the CPUG was only 0.14 K and contributed to curbing urban warming by 9.93%. We further revealed that urbanization and major ecological restoration projects are the key factors influencing CPUG, emphasizing the need for anthropogenic vegetation management to curb urban warming. The proposed model in this study provides a powerful tool for quantitatively assessing the impact of long-term UG trends on urban warming. The results of the study are an important reference for building climate-adaptive cities.

Membrane-based desalination is essential for mitigating global water scarcity; yet, the process is energy-intensive and heavily reliant on fossil fuels, resulting in substantial carbon emissions. To address the challenges of treating seawater, produced water, brackish groundwater, and wastewater, we have developed a thin air gap membrane distillation (AGMD) system featuring a novel slippery condensing surface. The quasi-liquid slippery surface facilitates efficient condensate water droplet removal, allowing for the implementation of a 1 mm thin air gap. This advancement has led to a 2-fold increase in permeate flux without lowering the thermal efficiency while preventing permeate flooding. Furthermore, the thin AGMD system, employing a cost-effective zirconium nitride/poly(vinylidene fluoride) (ZrN-PVDF) composite membrane, has been demonstrated for solar-driven desalination. Experimental results indicate that reducing the air gap from 2 to 1 mm enhances the permeate flux by 150%.

A solar-driven thin air gap membrane distillation system has been developed to boost clean water production by 150%, promising great potential in high-salinity and unconventional water purification.

Natural gas (NG) is expected to provide a substantial portion of electricity generation in many jurisdictions for the foreseeable future. Postcombustion carbon capture and storage (CCS) effectively abates direct CO₂ emissions; however, indirect NG supply chain emissions in most jurisdictions are incompatible with climate change mitigation goals. This life cycle assessment evaluates specific opportunities to reduce the carbon footprint of combined cycle gas turbine (CCGT) generation with CCS using existing low-emission NG production practices, technologies, and processes combined with emerging CCS techniques to achieve high CO₂ capture rates and mitigate startup emissions. We find baseload life cycle greenhouse gas (GHG) emission intensity ranges from 22 to 62 kgCO₂e/MWh for 95–98.5% CO₂ capture, within the range of published estimates for wind and photovoltaic power and considerably below prior estimates of CCGT with CCS. Low-emission NG production practices reduce other environmental impacts, which are dominated by combustion-related air pollution. We also show how interim solvent storage can effectively mitigate emissions from CCGT start/stop cycles. This work highlights the importance of mitigating both CO₂ and methane emissions from NG supply chains and proposes a more nuanced discussion regarding the potential contribution of NG to the future energy supply. A surrogate model is provided to estimate life cycle GHG emissions for CCGT with CCS and user-input parameters.

First LCA of electricity generation from natural gas with best practices in supply chain emissions; shows carbon footprint could be comparable to wind turbines and 63–71% lower than photovoltaics.