In the region of large gas fields, extensive research has been conducted on earthquakes induced by industrial production in shale gas fields. However, limited attention has been given to the impact of post-earthquake events on shale gas reservoir leakage and fault activation. The Luxian MS 6.0 earthquake, which occurred on 16 September 2021 in the Luzhou shale gas field, has raised concerns about post-earthquake shale gas leakage. Postearthquake measurements of soil gases (Rn, CO2, CH4, and H2) and isotopic analyses (delta 13CCO2, delta 13CCH4 and delta DCH4) in the Luzhou shale gas field area reveal that the Huayingshan fault zone, a natural pathway for shale gas leakage, was not activated by the Luxian earthquake and did not exhibit any further shale gas leakage after the 2021 earthquake. Furthermore, the seismogenic fault, which was impacted by the earthquake, did not damage the shale gas reservoir, causing shale gas leakage. This study provides an important foundation for future research on shale gas extraction and seismic activity in the region.

The urgency of protecting ecosystems and their recovery from contamination has been highlighted in several recent European strategies because Europe's biodiversity and landscapes are declining rapidly due to different human pressures. Despite the existence of EU and national laws addressing environmental contamination, practical procedures are often missing. For example, competent authorities must deal promptly and effectively with environmental accidents, noncompliance, and criminal offenses but relevant tools that facilitate these processes are often lacking. For example, thorough planning is crucial for effective investigation and assessment to improve environmental damage assessments in line with the European Environmental Liability Directive (ELD, 2004/35/EC). With regard to soils, a specific European legislation for their protection, the European Soil Monitoring Law, is currently being developed. However, it is crucial that this law bridges the gaps between existing chemical regulations and that it aligns with current European strategies for environmental protection and sustainability. Continuous feedback of soil monitoring results to regulatory frameworks will be essential. This feedback loop ensures that chemical regulations are relevant and effective in protecting soil health. In this context, development and sharing of effective and practical procedures for recovering ecosystems from contamination are crucial. This was the case at the RemTech Europe meeting, which was held online and onsite in Ferrara, Italy, in September 2022. The discussion covered all aspects of environmental contaminants. It ranged from the basic understanding of these contaminants to the various types that pose a threat to organisms, studies of their environmental fate, detection methods, and sustainable practices for contaminant management. The special series dedicated to RemTech Europe 2022 is particularly relevant to these purposes and resulted in six articles that were selected from oral presentations. The articles emphasize the need for integrated approaches to risk management and remediation to address the problems of soil, sediment, and groundwater contamination. Integr Environ Assess Manag 2024;00:1-5. (c) 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Microscale alterations in soil physical characteristics resulting from long-term soil health practices can contribute to changes in soil nitrous oxide (N2O) emissions. In this study, we investigated soil N2O emissions in relation to pore characteristics influencing soil gas diffusivity under long-term tillage and cover cropping practices. Intact soil cores from tillage (conventional tillage, Conv. T versus no tillage, NT) and cover crop (hairy vetch, HV versus no cover crop, NC) treatments were used for N2O measurements and computed tomography (CT) scanning. Using X-ray CT technique with a resolution of 59 mu m, pore structure parameters including macroporosity, number of macropores, anisotropy, fractal dimension, tortuosity, and connectivity were determined. The results showed that Conv. T and HV emitted significantly higher N2O than NT and NC, respectively. A similar trend was observed for macroporosity, Conv. T soils had 27.4 % higher CT-derived macroporosity than the NT soils and HV increased macroporosity by 31.1 % over the NC treatment. The number of macropores and fractal dimension were significantly higher whereas degree of anisotropy was significantly lower under HV compared to NC. In the upper 3 cm of soil, HV had a connected porosity, whereas the pores were disconnected and isolated in NC. These CTderived properties; however, were not impacted by tillage treatments. N2O emissions were positively and significantly correlated to relative soil gas diffusivity, CT -derived macroporosity, number of macropores, and fractal dimension. Our results demonstrated that soil macroporosity and relative gas diffusivity could lead to improved understanding and predictability of N 2 O emissions under high soil moisture conditions.

Ongoing studies conducted in northern polar regions reveal that permafrost stability plays a key role in the modern carbon cycle as it potentially stores considerable quantities of greenhouse gases. Rapid and recent warming of the Arc-tic permafrost is resulting in significant greenhouse gas emissions, both from physical and microbial processes. The po-tential impact of greenhouse gas release from the Antarctic region has not, to date, been investigated. In Antarctica, the McMurdo Dry Valleys comprise 10 % of the ice-free soil surface areas in Antarctica and like the northern polar regions are also warming albeit at a slower rate.The work presented herein examines a comprehensive sample suite of soil gas (e.g., CO2, CH4 and He) concentrations and CO2 flux measurements conducted in Taylor Valley during austral summer 2019/2020. Analytical results reveal the presence of significant concentrations of CO2, CH4 and He (up to 3.44 vol%, 18,447 ppmv and 6.49 ppmv, respec-tively) at the base of the active layer. When compared with the few previously obtained measurements, we observe increased CO2 flux rates (estimated CO2 emissions in the study area of 21.6 km2 approximate to 15 tons day-1). We suggest that the gas source is connected with the deep brines migrating from inland (potentially from beneath the Antarctic Ice Sheet) towards the coast beneath the permafrost layer. These data provide a baseline for future investigations aimed at monitoring the changing rate of greenhouse gas emissions from Antarctic permafrost, and the potential origin of gases, as the southern polar region warms.

Climate warming and subsequent permafrost thaw may result in organic carbon and nutrient stores being metabolized by microbial communities, resulting in a positive feedback loop of greenhouse gas (GHG) soil emissions. As the third most important GHG, understanding nitrous oxide (N2O) flux in Arctic mineral ice-wedge polygon cryosols and its relationship to the active microbial community is potentially a key parameter for understanding future GHG emissions and climatic warming potential. In the present study, metatranscriptomic analyses of active layer Arctic cryosols, at a representative ice-wedge polygon site, identified active nitrogen-fixing and denitrifying bacteria that included members of Rhizobiaceae, Nostocaceae, Cyanothecaceae, Rhodobacteraceae, Burkholderiaceae, Chloroflexaceae, Azotobacteraceae and Ectothiorhodospiraceae. Unique microbial assemblages with higher proportion of Rhodobacteriales and Rhocyclales were identified by targeted functional gene sequencing at locations with higher (P = 0.053) N2O emissions in the wetter trough soils compared with the dryer polygon interior soils. This coincided with a higher relative abundance of the denitrification nirS gene and higher nitrate/nitrite concentrations in trough soils. The elevated N2O flux observed from wetter trough soils compared with drier polygon interior soils is concerning from a climate warming perspective, since the Arctic is predicted to become warmer and wetter.