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Arsenic (As) and cadmium (Cd) are prevalent in paddy soils, posing potential threats to food safety and public health. The concentrations of soluble ​As and Cd are sensitive to moisture-driven changes in soil pH and Eh, which is rarely described at the critical dry-wet interface. Here, tempo-spatial changes of soluble As and Cd were captured by In-situ Porewater Iterative samplers at the capillary fringe that extended from saturated to unsaturated moisture gradient at the millimeter scale (60 ​mm profile in depth) through two episodic dry-wet cycles (55 days in total). The As and Cd concentrations showed less significant fluctuation in second cycle compared to the initial dry-wet cycle. The study also revealed at the capillary fringe profile (20–40 ​mm), the As concentrations increased from 4.6 μg L−1 in unsaturated soils to 13.5 μg L−1 in saturated soils, while Cd decreased from 3.3 to 0.2 μg L−1. This observed correlation was aligned with the vertical changes in soil Eh (+287 to +381 ​mV) and pH (3.42 to 6.07). This study found a distinct zone characterized by low As and low Cd concentrations, typically situated approximately 10–30 ​mm beneath the capillary fringe. Upon further analysis, it was determined that soil with an Eh of 249 ​mV and a pH of 4.3 potentially serves as an optimal environment for decreasing As and Cd levels in porewater. These findings suggest that it is feasible to reduce As and Cd concentration in the soil by implementing appropriate depth-controlled water management techniques.

Casehardening (σi) is an internal stress-related phenomenon that develops in kiln-dried wood materials, causing shape distortion. This study focuses on the impact of drying schedule and wood parameters (e.g., density, moisture) on σi. Results indicated that the wood's final moisture content level has the highest impact when it is above 15%. However, the wood moisture gradient is the most influential factor when wood's moisture content is below 15%. Drying schedule aggressiveness and post-drying treatments also affect σi; an aggressive drying schedule followed by conditioning remarkably reduces σi occurrence.

Urban wetlands play a crucial role in the regional carbon balance and regulation of greenhouse gas (GHG) emissions; however, the effects of restoration year and moisture gradient on methane (CH 4 ) fluxes during wetland restoration and their driving mechanisms are unclear. This study investigated CH 4 fluxes, environmental factors, and methanogenic communities in urban wetlands under different restoration years (2 years, 9 years, and natural wetland without restoration) and moisture gradients (perennial waterlogging, seasonal waterlogging, and no surface waterlogging) to reveal the spatial and temporal variation characteristics of CH 4 fluxes in urban wetlands and their regulatory mechanisms. The results indicated that wetlands with short-term restoration (2 years) exhibited significantly higher CH 4 fluxes under conditions of sufficient moisture (such as perennial waterlogging), whereas wetlands with long-term restoration (9 years) exhibited lower CH 4 fluxes. Furthermore, the average CH 4 fluxes under seasonal waterlogging (1.80 mg m -2 ·h -1 ) and no surface waterlogging gradients (0.04 mg m -2 ·h -1 ) were significantly lower than that under perennial waterlogging gradient (87.36 mg m -2 ·h -1 ). Variations in CH 4 flux were significantly regulated by key environmental factors (soil water content, soil organic matter, and soil temperature) and specific methanogenic communities (Methanospirillum and Methanoregula). Moreover, methanogenic communities can be altered by environmental factors that vary with restoration years and moisture gradients, leading to differences in wetland CH 4 fluxes. The results provide a new perspective on the spatial and temporal variations in CH 4 emissions from urban wetlands and identify key regulatory factors affecting CH 4 fluxes, providing a reference for evaluating the restoration effects of urban wetlands and improving governance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier Inc. All rights reserved.)

Water resources are essential for desert oases and are key drivers of local ecological processes critical to the growth of desert vegetation. In this study, the oasis in the hinterland of the Taklamakan Desert, China, was selected as the research subject. Using high-precision classification of oasis vegetation through machine learning, surface water within the oasis was identified and extracted from multi-year Landsat remote sensing data. The spatial distribution patterns of the main community-building species, Populus euphratica and Tamarix ramosissima, were studied under different moisture gradients using environmental covariates and measured groundwater depth to invert its spatial distribution and K-mean clustering to construct surface water and groundwater moisture gradients. The results indicated that the classification accuracy for the two species reached 0.917. Gradients 1-5 were used to categorize the water resources, dividing surface water and groundwater into five gradients. Gradient 3 exhibited the optimal moisture conditions, with a high surface water distribution frequency (0.017) and shallow groundwater depth (3.158 m), while Gradient 4 showed the least optimal moisture conditions, characterized by a low surface water distribution frequency (0.008) and deep groundwater depth (4.820 m). The water gradient decreased in the following order: Gradient 3 > Gradient 5 > Gradient 1 > Gradient 2 > Gradient 4. The optimum gradients for growth of P. euphratica and T. ramosissima were gradients 5, 1, and 2. The normalized vegetation index spatial distribution patterns of the two species were consistent with that of the moisture gradient. Tamarix ramosissima was found to be more tolerant to salinity and drought than P. euphratica. Overall, this study provides valuable information on the effect of the spatial distribution of water resource gradients on oasis vegetation and can guide future water delivery policies in oases., Competing Interests: Declaration of competing interest The authors declare that they have no competing financial interests or personal relationships that may have influenced the work reported in this study., (Copyright © 2024 Elsevier B.V. All rights reserved.)

High-mountain plant communities are strongly determined by abiotic conditions, especially low temperature, and are therefore susceptible to effects of climate warming. Rising temperatures, however, also lead to increased evapotranspiration, which, together with projected shifts in seasonal precipitation patterns, could lead to prolonged, detrimental water deficiencies. The current study aims at comparing alpine plant communities along elevation and water availability gradients from humid conditions (north-eastern Alps) to a moderate (Central Apennines) and a pronounced dry period during summer (Lefka Ori, Crete) in the Mediterranean area. We do this in order to (1) detect relationships between community-based indices (plant functional leaf and growth traits, thermic vegetation indicator, plant life forms, vegetation cover and diversity) and soil temperature and snow duration and (2) assess if climatic changes have already affected the vegetation, by determining directional changes over time (14-year period; 2001-2015) in these indices in the three regions. Plant community indices responded to decreasing temperatures along the elevation gradient in the NE-Alps and the Apennines, but this elevation effect almost disappeared in the summer-dry mountains of Crete. This suggests a shift from low-temperature to drought-dominated ecological filters. Leaf trait (Leaf Dry Matter Content and Specific Leaf Area) responses changed in direction from the Alps to the Apennines, indicating that drought effects already become discernible at the northern margin of the Mediterranean. Over time, a slight increase in vegetation cover was found in all regions, but thermophilisation occurred only in the NE-Alps and Apennines, accompanied by a decline of cold-adapted cushion plants in the Alps. On Crete, xeromorphic shrubs were increasing in abundance. Although critical biodiversity losses have not yet been observed, an intensified monitoring of combined warming-drought impacts will be required in view of threatened alpine plants that are either locally restricted in the south or weakly adapted to drought in the north., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)