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Understanding the relationship between soil moisture and vegetation is crucial for future projections of ecosystem and water resources. While their hysteresis loop relationship, which arises from their asynchrony in intra-annual variation, remains underexplored. This study used the hysteresis loop type and area (Ah) to characterize the relationship between root zone soil moisture (RZSM) and normalized difference vegetation index (NDVI) across China from 1986 to 2015, and examined its ecological implications. The results identified four types of hysteresis loops. The clockwise loop, with a delayed single peak of RZSM relative to NDVI, was primarily found in north China and the Qinghai-Tibet Plateau, indicating severe water limitation during early growth period. The counterclockwise loop, with an advanced single peak of RZSM relative to NDVI, was common in southeast China's forest, suggesting a shift towards energy limitation. The 8-shaped loop, resulting from double peaks in either RZSM or NDVI due to climate change (e.g., snowmelt) and human disturbance (e.g., irrigation and crop harvest), was observed in northwest China's glaciers and croplands in south and northeast China. The multicrossed loop, marked by multimodal intra-annual variations in both RZSM and NDVI, was predominantly found in northwest China's barren lands. Additionally, from 1986 to 2015, this study observed a shift from 8-shaped or multi-crossed loops to clockwise or counterclockwise loops in some regions like the Yellow River Basin, implying a trend of revegetation. Furthermore, a higher Ah generally indicated more severe water limitation or greater mismatch between RZSM and NDVI. Significant changes in Ah, such as increases in the Yellow River Basin, suggested intensified water limitations, while decreases in southeast and northwest China pointed to an earlier peak of the growing and rainy seasons. This study provides insights into the dynamic interactions between soil moisture and vegetation, offering valuable guidance for ecological management across diverse ecosystems.

期刊论文 2025-09-15 DOI: 10.1016/j.agrformet.2025.110714 ISSN: 0168-1923

Climate change is transforming the ice-free areas of Antarctica, leading to rapid changes in terrestrial ecosystems. These areas represent <0.5% of the continent and coincide with the most anthropogenically pressured sites, where the human footprint is a source of contamination. Simultaneously, these are the locations where permafrost can be found, not being clear what might be the consequences following its degradation regarding trace element remobilisation. This raises the need for a better understanding of the natural geochemical values of Antarctic soils as well as the extent of human impact in the surroundings of scientific research stations. Permafrost thaw in the Western Antarctic Peninsula region and in the McMurdo Dry Valleys is the most likely to contribute to the remobilisation of toxic trace elements, whether as the result of anthropogenic contamination or due to the degradation of massive buried ice and ice-cemented permafrost. Site-specific locations across Antarctica, with abandoned infrastructure, also deserve attention by continuing to be a source of trace elements that later can be released, posing a threat to the environment. This comprehensive summary of trace element concentrations across the continent's soils enables the geographical systematisation of published results for a better comparison of the literature data. This review also includes the used analytical techniques and methods for trace element dissolution, important factors when reporting low concentrations. A new perspective in environmental monitoring is needed to investigate if trace element remobilisation upon permafrost thaw might be a tangible consequence of climate change.

期刊论文 2025-09-01 DOI: 10.1016/j.earscirev.2025.105171 ISSN: 0012-8252

Emerging contaminants and climate change are major challenges that soil organisms are facing today. Triclosan (TCS), an antibacterial agent, is widespread and hazardous in terrestrial environments, but there is a lack of information on how its toxicity will change because of climate change. The aim of the study was to evaluate the short-term effects of increased temperature, decreased soil moisture content (drought), and their complex interaction on triclosan-induced biochemical changes in Eisenia fetida (as well as growth and survival). Four different treatments were used in TCS-contaminated soil tests with E. fetida (10-750 mg TCS kg-1): C (21 degrees C + 60 % water holding capacity (WHC)), D (21 degrees C and 30 % WHC), T (25 degrees C + 60 % WHC), and T + D (25 degrees C + 30 % WHC). The more prominent TCS effect on the survival was seen only after two weeks and at the high TCS concentrations, though a negative effect on weight growth was recorded after one week of exposure at all tested TCS concentrations and climate conditions. Under standard (C) conditions, an activated E. fetida antioxidative system effectively reduced the oxidative stress induced by TCS. Changes in the climatic conditions influenced E. fetid a's biochemical response to TCS-induced oxidative stress. Despite the enhanced activity of antioxidant enzymes, the combination of drought (D) and TCS caused significant lipid peroxidation in E. fetida. Under elevated temperature, E. fetida experienced oxidative stress and a considerable rise in lipid peroxidation due to insufficient activation or inhibition of antioxidant enzymes.

期刊论文 2025-09-01 DOI: 10.1016/j.envres.2025.121923 ISSN: 0013-9351

The incorporation of PCMs in energy piles holds significant potential for revolutionising thermal management in construction, making them a crucial component in the development of next-generation systems. The existing literature on PCM-integrated energy piles largely consists of isolated case studies and experimental investigations, often focusing on specific aspects without providing a comprehensive synthesis to guide future research or practical applications. To date, no review has been conducted to consolidate and evaluate the existing knowledge on PCMs in energy piles, making this review the first of its kind in this field. Up until now, this gap in research has limited our understanding of how PCM configurations, thermal properties, and integration methods impact the thermal and mechanical performance of these systems. Through thoroughly analysing the current research landscape, this review discovers key trends, methodologies, and insights. The methodology used here involved a systematic search of the existing SCI/SCIE-indexed literature to ensure a structured review. Based on the SLR findings, it is evident that current research on PCMs in energy piles is focused on improving thermal efficiency, heat transfer, and compressive strength. Furthermore, precise adjustments in melting temperature significantly impact efficiency, with PCM integration boosting thermal energy extraction by up to 70 % in some cases, such as heating cycles, and saving up to 30 % in operational costs. PCMs also reduce soil temperature fluctuations, improving structural integrity through minimising axial load forces. However, challenges remain, including reduced mechanical strength due to voids and weak bonding, high costs, and complexities such as micro-encapsulation. We acknowledge that there are gaps in addressing certain key factors, including thermal diffusivity; volume change during phase transitions; thermal response time; compatibility with construction materials; interaction with soil, creep, and fatigue; material compatibility and durability; and the long-term energy savings associated with PCM-GEP systems.

期刊论文 2025-09-01 DOI: 10.1016/j.applthermaleng.2025.126630 ISSN: 1359-4311

With changing climate and increased frequency of wet weather extremes, increased attention is being directed towards understanding the resilience of agroecosystems and the goods and services they deliver. The world's most instrumented and monitored farm (the North Wyke Fam Platform - a UK National Bioscience Research Infrastructure) has been used to explore the resilience of sediment loss regulation delivered by lowland grazing livestock and arable systems under conventional best management. The robustness of water quality regulation was explored using exceedance of modern background (i.e. pre-World War II) net soil loss rates (i.e., sediment delivery) during both typical (2012-13, 2015-16) and the most extreme (2013-14, 2019-20, 2023-24) winters (December - February, inclusive), in terms of seasonal rainfall totals, over the past similar to decade. Exceedances of maximum modern background sediment loss rates from pasture were as high as 2.4X when scheduled ploughing and reseeding for sward improvement occurred immediately prior to the winters in question. Exceedances of maximum modern background sediment loss rates in the arable system (winter wheat and spring oats) were as high as 21.7X. Over the five monitored winters, the environmental damage costs for cumulative sediment loss from the permanent pasture system ranged from pound 163-203 and pound 197-245 ha(-1) to pound 321-421 and pound 386-507 ha(-1). Over the same five winters, environmental damage costs for cumulative sediment loss from catchments subjected to reseeding and, more latterly, arable conversion, ranged between pound 382-584 and pound 461-703 ha(-1) to pound 1978-2334 and pound 2384-2812 ha(-1). Our data provide valuable quantitative insight into the impacts of winter rainfall and land use on the resilience of sediment loss regulation.

期刊论文 2025-09-01 DOI: 10.1016/j.agee.2025.109713 ISSN: 0167-8809

Investigating water ice content at different locations on the Moon is crucial for crewed space missions and serves as a foundation for establishing lunar bases, which necessitates lunar soil sampling to gather information. Aiming to minimize the water ice loss caused by heat generation during drilling, this paper proposes a water ice highconservation sampling system based on frozen CO2 spray cooling. The thermodynamic and hydrodynamic models of the frozen CO2 generation subsystem and heat exchange subsystem are established. The impact of design parameters, flow and thermal conditions, and operation modes on water content has been analyzed. The spray cooling method indirectly affects the lunar soil temperature by reducing the drill bit temperature to increase the water conservation ratio (WCR) during drilling. The method combines frozen CO2 sublimation heat flow and jet cooling flow. Jet cooling is closely associated with the temperature difference between the fluid and the drill bit, as well as the flow velocity. Meanwhile, sublimation heat flow depends on the temperature difference between the drill bit and the saturation temperature of frozen CO2, along with the content of frozen CO2. Jet cooling is predominant at lower mass flow rates, while sublimation cooling prevails at higher rates. In addition, the time the lunar soil is at low-sublimation temperature is an important factor in WCR. Thus, to increase WCR, one can enhance flow velocity by reducing the nozzle diameter, raise sublimation heat flow by increasing mass flow and lowering the initial temperature, and maintain lunar soil at low-sublimation temperatures by increasing cooling time, duty ratio and decreasing the cooling period. Among others, increasing the cooling time has the most significant effect. The increasing slopes of WCR with cooling durations are about 20 %/100 s (at 0.4 g/s, liquid CO2) and 10 %/100 s (at 0.1 g/s, liquid CO2). However, the cooling time should not exceed the drilling time. This study provides an effective water ice conservation system that is useful for other planetary sampling missions.

期刊论文 2025-09-01 DOI: 10.1016/j.applthermaleng.2025.126629 ISSN: 1359-4311

Small modular reactors (SMRs) are an alternative for clean energy solutions in Canada's remote northern communities, owing to their safety, flexibility, and reduced capital requirements. Currently, these communities are heavily reliant on fossil fuels, and the transition to cleaner energy sources, such as SMRs, becomes imperative for Canada to achieve its ambitious net-zero emissions target by 2050. However, applying SMR technology in permafrost regions affected by climate change presents unique challenges. The degradation of permafrost can lead to significant deformations and settlements, which can result in increased maintenance expenses and reduced structural resilience of SMR infrastructure. In this paper, we studied the combined effect of climate nonstationarity in terms of ground surface temperature and heat dissipation from SMR reactor cores for the first time in two distinct locations in Canada's North: Salluit in Quebec and Inuvik in the Northwest Territories. It was shown that these combined effects can make significant changes to the ground thermal conditions within a radius of 15-20 m around the reactor core. The change in the ground thermal conditions poses a threat to the integrity of the permafrost table. The implementation of mitigation strategies is imperative to maintain the structural integrity of the nuclear infrastructure in permafrost regions. The thermal modeling presented in this study paves the way for the development of advanced coupled thermo-hydromechanical models to examine the impact of SMRs and climate nonstationarity on permafrost degradation.

期刊论文 2025-09-01 DOI: 10.1061/JCRGEI.CRENG-804 ISSN: 0887-381X

With polar amplification warming the northern high latitudes at an unprecedented rate, understanding the future dynamics of vegetation and the associated carbon-nitrogen cycle is increasingly critical. This study uses the dynamic vegetation model LPJ-GUESS 4.1 to simulate vegetation changes for a future climate scenario, generated by the EC-Earth3.3.1 Earth System model, with the forcing of a 560 ppm CO2 level. Using climate output from an earth system model without coupled dynamic vegetation, to run a higher resolution dynamic vegetation standalone model, allows for a more in depth exploration of vegetation changes. Plus, with this approach, the drivers of high latitude vegetation changes are isolated, but there is still a complete understanding of the climate system and the feedback mechanisms that contributed to it. Our simulations reveal an uneven greening response. The already vegetated Southern Scandinavia and western Russia undergo a shift in species composition as boreal species decline and temperate species expand. This is accompanied by a shift to a carbon sink, despite higher litterfall, root turnover and soil respiration rates, suggesting productivity increases are outpacing decomposition. The previously barren or marginal landscapes of Siberia and interior Alaska/Western Canada, undergo significant vegetation expansion, transitioning towards more stable, forested systems with enhanced carbon uptake. Yet, in the previously sparsely vegetated northern Scandinavia, under elevated CO2 temperate species quickly establish, bypassing the expected boreal progression due to surpassed climate thresholds. Here, despite rising productivity, there is a shift to a carbon source. The deeply frozen soils in central Siberia resist colonisation, underscoring the role of continuous permafrost in buffering ecological change. Together, these results highlight that CO2 induced greening does not always equate to enhanced carbon sequestration. The interplay of warming, nutrient constraints, permafrost dynamics and disturbance regimes creates divergent ecosystem trajectories across the northern high latitudes. These findings illustrate a strong need for regional differentiation in climate projections and carbon budget assessments, as the Arctic's role as a carbon sink may be more heterogeneous and vulnerable than previously assumed.

期刊论文 2025-09-01 DOI: 10.1016/j.ecolmodel.2025.111193 ISSN: 0304-3800

Use of forest biomass may induce changes in the aerosol emissions, with subsequent impacts on the direct and indirect climate effects of these short-lived climate forcers. We studied how alternative wood use scenarios affected the aerosol emissions and consequent radiative forcing in Finland. In all alternative scenarios, the harvest level of forest biomass was increased by 10 million m3 compared to the baseline. The increased biomass harvest was assigned to four different uses: (i) to sawn wood, (ii) to pulp-based products, (iii) to energy biomass combusted in small-scale appliances or (iv) to energy biomass combusted in medium-to-large scale boilers. Aerosol emissions (black carbon (BC), organic carbon (OC) and sulphur dioxide (SO2)) under these scenarios were estimated using displacement factors (DFs). The global aerosol-climate model ECHAM-HAMMOZ was used to study instantaneous radiative forcing due to aerosol-radiation interactions (IRFARI) and effective radiative forcing (ERF), based on the differences in aerosol emissions between the alternative wood use scenarios and the baseline scenario. The results indicated that the use of sawn wood and energy biomass combusted in medium- to large-scale boilers decreased radiative forcings, implying climate cooling, whereas the increased use of pulpwood increased them. Energy biomass combustion in small-scale appliances increased IRFARI by 0.004 W m-2 but decreased ERF by -0.260 W m-2, specifically due to a strong increase in carbonaceous aerosols. Alternative use of forest biomass notably influenced aerosol emissions and their climate impacts, and it can be concluded that increased forest biomass use requires a comprehensive assessment of aerosol emissions alongside greenhouse gases (GHGs). Given the consequent reduction in radiative forcing from aerosol emissions, we conclude that the greatest overall climate benefits could be achieved by prioritising the production of long-lived wood-based products.

期刊论文 2025-08-21 DOI: 10.1111/gcbb.70041 ISSN: 1757-1693

Land-cover changes and new ecosystem trajectories in Interior Alaska have altered the structure and function of landscapes, with regional warming trends altering carbon and water cycling. Notably, these changes include the increased distribution of tall woody vegetation, trees and shrubs, in landscapes that historically only supported low shrub vegetation cover. In Denali National Park, Alaska, this phenomenon has altered primary succession pathways towards tundra ecosystems with the establishment and expansion of balsam poplar (Populus balsamifera) trees. In this study, we examine how snow, soil, and vegetation processes interact within this altered successional pathway towards further landscape change following glacial recession. In a sequence of outflow terraces, we found that variations in snow depth, functional soil depth, leaf area index, overstory height, and understory height were all significantly correlated with each other, with those effects largely explained by the presence of poplar. Poplar-dominated plots had deeper snowpacks, deeper functional soil depths, taller overstory and shrub heights, and greater LAI than in non-poplar plots of the same landscape age. These findings suggest a feedback cycle where the establishment of taller vegetation (here, poplar) alters ecosystem processes in the following notable ways: taller vegetation is able to trap more snow by reducing wind exposure and limiting sublimation; this snow provides water through additional snowmelt and insulation, keeping soils warmer and lessening permafrost development, leading to deeper functional soil depths. This feedback demonstrates poplar's ability to modify the environment as an ecosystem engineer, engineering a trajectory away from the otherwise expected permafrost-underlain tundra.

期刊论文 2025-08-19 DOI: 10.1002/ece3.71974 ISSN: 2045-7758
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