Microbial mechanisms regulate soil carbon dynamics under nitrogen addition in mangrove wetlands of Dongzhai Harbor, Southern China.

Coastal marsh conversion to paddy fields leads to a more pronounced stimulation of temperature sensitivity of soil microbial respiration in higher-latitude regions.

Antibiotic resistance genes across divergent wetland types: Profiles, driving mechanisms, and risk assessment.

Spatiotemporal reorganization of coastal wetlands along the Pakistan coast under climatic variability and human modification (2019-2024)

• Soil physicochemical traits and microbes characterized along a salinity gradient • Salinity, sulfur, and iron shape microbial structure across wetlands • Sulfur-reducing bacteria dominate highly saline soils • Salinization lowers CH 4 but increases CO 2 emissions Coastal wetlands play a critical role in carbon sequestration, biogeochemical cycling, and ecosystem stability. These habitats support diverse microbial communities that regulate organic matter decomposition and greenhouse gas fluxes, influencing climate-related feedback mechanisms. However, rising sea levels and saltwater intrusion may disrupt microbial processes, particularly those associated with the sulfur cycle and methane dynamics. Here, we characterize soil physicochemical properties and microbial communities along a salinity gradient in three temperate coastal wetlands to assess the impact of salinity on organic matter decomposition and greenhouse gas emissions. Using full-length Oxford Nanopore MinION 16S rRNA amplicon sequencing, we analyzed microbial communities across freshwater, brackish, and saline wetland soils. Our results indicate that sulfur-reducing bacteria dominate salinized sites, while brackish environments are characterized by obligate anaerobic taxa involved in sulfate reduction, fatty acid degradation, and denitrification. These microbial assemblages contribute to lower CH 4 emissions but increased CO 2 fluxes in the brackish areas, highlighting key microbial-mediated trade-offs in wetland carbon cycling. By integrating microbial diversity, and metabolic functions with soil geochemistry, this site-specific but ecologically meaningful case study improves our understanding of microbe-soil interactions in temperate wetland ecosystems facing increased salinization due to climate change.

The natural protection offered by saltmarsh and mangrove wetlands is increasingly recognised and there is widespread interest in understanding this phenomenon to assist nature-based coastal interventions. Roughness plays a fundamental role in shallow-water hydrodynamic process and hence is a critical parameter for simulating flow over coastal vegetation and the resulting dynamics of surge and wave attenuation. This study provides a comprehensive review of our understanding of the Manning’s coefficient (T/L 1/3 ) in saltmarsh and mangroves. The literature was screened using a rigorous selection procedure to identify studies relevant to saltmarsh and mangrove hydrodynamics and bed roughness. Considering all the numerical, laboratory and field studies that used Manning’s coefficient in saltmarsh and mangrove ecosystems, 36 papers were identified and assessed. The results indicate an interquartile range of Manning’s coefficient (s/m 1/3 ) from 0.04 to 0.08 for saltmarshes and 0.10 to 0.14 for mangroves, providing indicative ‘global’ estimates for these two coastal wetland types. Geographic location, tidal range and temperature showed no statistical relationship, supporting the use of global indicative values. However, statistical testing reveals that the Manning’s coefficient for saltmarshes and mangroves do show significant cross-shore variability with increasing values from the seaward to landward direction. This should be considered and further assessed, especially in more detailed studies. Hence, this analysis provides an indicative ‘global’ constant estimate of Manning’s coefficient for saltmarshes and mangroves, as well as suggestions for more systematic future research on wetland roughness. • A global review of Manning’s number in saltmarsh and mangrove wetlands is presented. • Global assessment of supporting nature based solutions restoring coastal wetlands • Indicative Manning’s values: 0.04–0.08 for saltmarsh and 0.10–0.14 for mangroves. • No statistical link found between Manning’s number and location, tide or temperature. • Cross-shore variability of roughness is significant and needs further investigation.

Ecological impacts of herbicide control in a protected coastal wetland of Chongming Island (Yangtze River Estuary, eastern China) assessed using macrobenthic indicators.

Ecological water replenishment enhances nitrogen removal potential in coastal wetlands by mediating root exudate composition and sediment chemistry.

Biomass prediction and invasion assessment of Spartina alterniflora driven by remote sensing big data.

Water variability impacts on conifer growth: Evaluating three multiscalar indices to clarify climate–growth relationships in northwestern Patagonia

Distribution pattern and influencing factors of soil stable carbon isotopes in global coastal wetlands

Coastal wetlands act as significant natural sources of the potent greenhouse gas, methane (CH4). While burrowing benthos such as crabs are recognized as important regulators of biogeochemical processes in these ecosystems, their specific impacts on CH4 oxidation and the underlying mechanisms remain poorly understood. Here, we demonstrate that crab bioturbation substantially enhances potential aerobic and anaerobic CH4 oxidation within burrow systems. This stimulatory effect exhibits distinct spatial heterogeneity, diminishing with an increase in the distance from the burrow walls. We found that this heterogeneity is driven by the three-dimensional burrow architecture, which establishes steep gradients in physicochemical conditions, electron-acceptor availability, and the abundance of CH4-oxidizing microorganisms. Furthermore, total organic carbon, salinity, the Fe2+/Fe3+ ratio, and nutrient contents were identified as key environmental predictors of the CH4 oxidation dynamics. These findings advance the mechanistic understanding of CH4 sinks in complex coastal habitats and provide a critical scientific basis for accurately assessing wetland carbon budgets in the context of global climate change.

Iron plaque drives mangrove arsenic detoxification and root adaptation in coastal wetland Avicennia marina seedlings.

Coastal wetlands are highly sensitive groundwater-dependent ecosystems whose sustainability is strongly influenced by groundwater-surface water interactions. The Anzali Wetland in northern Iran is hydraulically connected to the shallow Foumanat coastal aquifer and receives inflow from multiple rivers and tributaries. In this study, the integrated MIKE SHE-MIKE 11 modeling framework was applied to simulate coupled hydrological processes and evaluate the relative impacts of groundwater abstraction and river-flow variations on wetland sustainability. The model was calibrated and validated using hydrometeorological, groundwater-level, and river-discharge data, demonstrating satisfactory performance in reproducing regional hydrological dynamics. Four diagnostic stress-test scenarios were developed to assess the effects of groundwater abstraction (± 30%) and river-discharge variations (± 50%) under wet, normal, and dry hydrological conditions. The results showed that groundwater abstraction is the dominant factor controlling groundwater levels and wetland-aquifer hydraulic connectivity. A 30% increase in pumping caused groundwater-level declines of up to 1.38m near the wetland and intensified downward hydraulic gradients, promoting seepage losses from the wetland toward the aquifer. In contrast, reducing pumping by 30% increased groundwater levels by up to 1.56m and partially restored more favorable hydraulic conditions between the wetland and aquifer. Although river inflows contributed locally to groundwater recharge near hydraulically connected channels, river-discharge variations produced only localized effects and could not compensate for the regional impacts of groundwater abstraction. The findings demonstrate that sustainable protection of the Anzali Wetland depends primarily on sustainable groundwater management rather than on surface-water regulation alone, highlighting the need for integrated groundwater abstraction control and aquifer-recharge strategies under increasing climatic and anthropogenic stress.

The contamination of wheat by aflatoxins, mainly resulting from fungal development during storage, represents a significant public health concern due to their well-documented carcinogenic effects. This study aimed to quantify aflatoxin contamination levels (AFB1, AFB2, AFG1, and AFG2) in Triticum durum wheat samples stored in four regions of Morocco, characterised by climatic conditions ranging from semi-arid to sub-humid. Aflatoxin B1 (AFB1) was detected in 27% of the analysed samples, with quantifiable concentrations ranging from 0.025 to 20.95 µg/kg. Among the AFB1-contaminated samples, 58% exceeded the regulatory limit. Traces of aflatoxin B2 (AFB2) and aflatoxin G2 (AFG2) were also detected in some samples. Aflatoxin occurrence appeared to be associated with regional climatic conditions, with higher contamination levels observed in humid coastal areas than in semi-arid regions. Molecular analysis of wheat samples corroborated the findings obtained by HPLC with fluorescence detection (HPLC-FLD) by revealing the presence of multiple Aspergillus species, including A. flavus (19.4%), A. aflatoxiformans (11.6%), A. versicolor (5.2%), A. nidulans (4.9%), and A. nomius (3.1%). Furthermore, the key genes involved in aflatoxin biosynthesis, aflR and omtA, were detected in all identified aflatoxigenic strains using multiplex PCR. Moreover, AFB1, the most toxic aflatoxin, was consistently detected in bread samples prepared from contaminated wheat grain. Although its concentration decreased by 40% to 70% during the baking process, the toxin remained present at concerning levels, underscoring the persistent health risk associated with aflatoxin contamination. These findings highlight the need for enhanced monitoring and control measures throughout the wheat production and storage chain to mitigate potential health hazards.

ABSTRACT Capsule Artificial nests are often used in ecological studies, but our research on Estonian coastal grasslands shows they differ significantly from natural nests in predation rates and predator identity, highlighting the importance of studying natural nests whenever possible. Aims Artificial nests may serve as an alternative to natural ones in studies of nest predation, but it is crucial to evaluate their suitability within specific local contexts. Methods We conducted a comparative analysis of daily survival rates between artificial and natural nests of waders in coastal grassland habitat in Estonia over two breeding seasons. Additionally, we employed camera traps to identify predators on a subset of nests. Results Our findings reveal discrepancies in nest survival and observed predators between artificial and natural nests, as well as annual differences. These results indicate that, at least in our study area, artificial nests are not an adequate substitute for natural nests when studying nest survival or when identifying nest predators. Conclusions Consistent with previous authors’ conclusions, we encourage ornithologists to invest time and effort in locating and studying natural nests whenever it is feasible to do so.

BackgroundUnderstanding the vertical distribution and storage of soil organic carbon (SOC) in arid coastal salt marshes is essential for assessing their role in blue-carbon sequestration. This study examines SOC patterns in marshes dominated by Arthrocnemum macrostachyum, Halocnemum strobilaceum, and Salicornia fruticosa, as well as unvegetated areas. Using 200 soil cores (2,000 samples), we applied allometric, exponential, and sigmoid models to predict volumetric SOC density (SOCv; kg C/m³) and cumulative SOC stocks (SOCc; kg C/m²) across depth profiles.ResultsSOC content showed an inverse exponential relationship with soil bulk density across vegetation types, consistent with patterns documented in other salt-marsh and coastal wetland systems. The allometric model provided the best SOCv predictions for A. macrostachyum, whereas the sigmoid model performed best for H. strobilaceum, S. fruticosa, and unvegetated sites, based on mean normalized average error (MNAE), mean normalized bias (MNB), and residual mean squares (RMS). All three models accurately reproduced SOCc for within-core depth extrapolation, with no significant differences between measured and predicted values within the validation dataset.ConclusionsThis study provides an improved understanding of SOC dynamics in arid coastal salt marshes and demonstrates the utility of depth-based mathematical models for predicting SOC storage. These findings support local-scale efforts to evaluate carbon-sequestration potential, though broader spatial validation across heterogeneous landscapes remains necessary.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12870-026-09221-2.

Simulating ecosystem resilience: Tipping point evasion driven by adaptive plant-pollinator interaction.

The continued loss and degradation of wetlands pose major challenges to global waterbird conservation. In response, large-scale wetland restoration projects have been widely implemented worldwide, yet their long-term ecological effectiveness has not been sufficiently evaluated. Here, we assessed the long-term impacts of wetland restoration on waterbird communities at Chongming Dongtan Wetland, China, using 17 years of monitoring data spanning pre-restoration, restoration, and post-restoration phases. Our results suggest that the Ecological Control of Spartina alterniflora and Improvement of Bird Habitats substantially enhanced waterbird diversity, with both species richness and total abundance increasing significantly after restoration. Restored artificial wetlands supported particularly high abundances of waterbirds, confirming their role as critical supplementary habitats alongside natural tidal flats. Notably, different waterbird guilds exhibited pronounced seasonal shifts in habitat use: the Anatidae predominated during the wintering period, whereas Waders dominated during spring and autumn migrations, and the degree of reliance on artificial versus natural wetlands varied markedly between guilds and across seasonal cycles. Beyond local effects, we detected a clear spillover effect, whereby increases in waterbird abundance and species richness were also observed in adjacent non-restored natural intertidal mudflats following restoration. In addition, several threatened and nationally protected species were recorded exclusively during the post-restoration phase, indicating improved habitat suitability for conservation-priority taxa. Overall, our findings highlight that wetland restoration can generate both local and landscape-scale biodiversity benefits, emphasizing the importance of incorporating habitat heterogeneity, seasonal habitat requirements, and spillover effects into coastal wetland restoration and management strategies.

Vegetation succession enhances soil organic carbon sequestration by modulating microbial carbon cycling genes in coastal marshes, eastern China.