Wetland loss and degradation over the past century have led to significant population declines in many waterbird species. Although wetland restoration is an effective measure for improving habitat quality and protecting threatened waterbirds, some projects failed to achieve their conservation targets. To enhance the effectiveness of restoration for waterbirds, this study proposes a four-step framework: 1) Determine the necessity and targets of restoration; 2) Develop and implement restoration measures based on the habitat requirements of conservation targets; 3) Conduct monitoring on waterbirds and their habitats and evaluate the effectiveness of restoration practice; 4) Apply adaptive management based on evaluation results to maximize restoration effectiveness. We applied this framework to the Chongming Dongtan wetland restoration project in the Yangtze Estuary, China. Using topographic modification, vegetation management, planting edible plants, and water level regulation, the project constructed foraging, high-tide roosting, and ground-nesting sites for waterbirds. Waterbird surveys, GPS tracking and camera traps were used to assess restoration effectiveness. The results showed that both species richness and abundance of waterbirds increased across four seasons in the restoration area. However, waterbird community significantly differed between the restoration area and the natural intertidal wetland. GPS tracking indicated that the restoration area was the main habitat for tagged birds in summer and winter. Moreover, breeding success rate within the restoration area was low due to flooding and nest predation. We recommend enhancing habitat quality for threatened species, adjusting water levels, and controlling predators. These findings provide guidance for wetland restoration practices aimed at waterbird conservation.

Coastal reclamation poses a significant threat to the ecological integrity and sustainability of China's coastal zone, prompting the implementation of stricter regulatory controls in recent years. However, a comprehensive understanding of long-term reclamation dynamics and the effectiveness of conservation initiatives over the past few decades remains limited. This study first quantified reclaimed areas and analyzed their spatial variability across multiple spatiotemporal scales using remote sensing-based land use and land cover change dataset (1990-2020). We then evaluated long-term trends in reclamation activities in relation to economic growth and policy interventions, which were hypothesized as primary drivers of reclamation dynamics. Our results indicate that land reclamation occurred extensively across all coastal regions, with the largest cumulative reclaimed areas concentrated in Shandong, Liaoning, and Jiangsu provinces. Each of these provinces exceeded 1,800 km2, collectively accounting for approximately 11,592.0 km2 of reclaimed land from 1990 to 2020. Reclamation expanded rapidly during 2000-2012 (40.9 km2 /yr), followed by a pronounced decline post-2012 (- 38.0 km2 /yr). This transition coincided with the implementation of policy-driven conservation measures, including the establishment of protected areas. Nevertheless, substantial spatial heterogeneity in reclamation patterns persisted, which reflected the influence of local development priorities and the variable effectiveness of regional conservation strategies. These findings suggest that China's coastal zone is undergoing a transformative shift from land-dependent development toward greener and more sustainable pathways. This study provides robust scientific evidence to support coastal management and offers critical insights for policymakers and stakeholders addressing coastal sustainability challenges at both regional and global scales.

Salt marsh soil organic carbon (SOC) is a key blue carbon pool affected by both disturbance and restoration; yet its long-term global dynamics remains poorly understood. Here we provide the global assessment of surface SOC changes in salt marshes from 2002 to 2019, combining multi-source remote sensing imagery with the machine learning calibrated by field observations. We find a net global SOC loss of 0.52 million tonnes, primarily driven by declines in North America and Oceania, which are only partially offset by gains in Asia and South America. The United States alone accounts for ~60% of the global loss, equivalent to 6.2 million tonnes of CO2 if fully released. Losses are concentrated in mature salt marshes with large SOC storage, while gains occur primarily in newly formed salt marshes with relatively low SOC density. These patterns suggest that global restoration efforts are failing to keep pace with degradation. To avert irreversible climate and ecological damage, the protection of mature, carbon-rich salt marshes must become a core component of global climate strategies.

Artificial reefs (ARs) are widely deployed as engineered coastal structures to enhance habitat complexity and support marine resource management, yet their impacts on marine viral ecology remain poorly understood. Viruses regulate microbial communities and biogeochemical processes, and their functional traits are sensitive to environmental change. Here, we investigated how artificial reefs influence viral community composition, functional gene profiles, and virus-environment interactions across paired reef and non-reef sites in coastal shelf systems. Using an integrated viromic and metagenomic approach, we compared viral assemblages in both seawater and sediments under artificial reef influence. ARs significantly modified seawater physicochemical conditions, including pH, sulfate concentration, dissolved oxygen, and salinity, whereas sediment properties remained largely unchanged. These environmental differences coincided with distinct virus-environment association patterns across habitats. Notably, artificial reefs were associated with viral functional profiles characterized by a reduced genomic representation of lysis-related genes and an increased representation of genes involved in DNA replication and nucleotide metabolism. Network analyses further showed differences in the balance of positive and negative virus-host correlations between AR and non-AR sites. Together, these results indicate that engineered coastal structures are linked to habitat-specific patterns in viral functional traits and virus-host associations. Our findings highlight viruses as sensitive indicators of anthropogenic habitat modification and underscore the importance of incorporating viral dynamics into assessments of microbial and biogeochemical responses in engineered coastal ecosystems.

Natural forest conversion profoundly alters soil respiration, yet its differential effects on autotrophic and heterotrophic components and their temperature sensitivity (Q10) remain unresolved globally. Here we synthesize 452 paired observations from 164 field studies, showing that soil respiration declines by 7.0% following forest conversion, primarily driven by a pronounced reduction in autotrophic respiration (-26.8%), whereas heterotrophic respiration exhibits no consistent response. Although Q10 does not shift significantly across all conversions, it increases markedly following conversion to agriculture (+8.8%) and grassland (+11.8%). Both soil respiration suppression and Q10 elevation are transient, converging toward adjacent forest levels within approximately 30 years. Variations in soil respiration reflect the opposing influences of soil organic carbon loss and post-conversion soil warming, whereas Q10 responses are strongly modulated by initial soil clay content and pH. Our findings underscore the need to incorporate component-resolved and context-dependent soil respiration and Q10 into Earth system models to improve projections of long-term carbon-climate feedbacks under land-use change.

Soil fungi are highly diverse and functionally pivotal in terrestrial ecosystems, yet the biogeographical patterns in anoxic wetlands remain poorly understood. Here, we synthesized a global dataset comprising 1,276 fungal amplicon sequencing samples from 239 sites and 311 biomass samples from 118 sites across natural wetlands. Using machine learning models, we identified key environmental drivers and resolved the global distribution patterns of fungal diversity and biomass. We found that fungal diversity peaked in inland wetlands, followed by coastal wetlands and peatlands. Notably, fungal amplicon sequence variants (ASVs) richness reached its maximum in mid-latitude regions (30–60°N) and was driven primarily by temperature variability and vegetation characteristics. In contrast, fungal biomass peaked in high-latitude (>60°N) regions and was positively associated with soil organic carbon (SOC) in anoxic wetlands. These findings refine our global understanding of mycological patterns and reveal predictable shifts in fungal communities along climatic, vegetation, and soil environmental gradients in anoxic wetlands.

Coastal salt marshes in China, one of the few countries to achieve net salt marsh gains in recent decades, are important blue carbon ecosystems. However, the lack of national-scale assessments of salt marsh changes and associated soil organic carbon (SOC) dynamics limits our understanding of their climate mitigation potential. Here we show how remote sensing and machine learning quantify changes in salt marsh area and surface SOC across China. Net salt marsh expansion is associated with overall gains in surface SOC, primarily through the conversion of aquacultural ponds, agricultural land and seawater areas, but these gains vary substantially across regions and periods. Salt marsh expansion and protection, particularly within protected areas, are associated with enhanced surface SOC. These findings highlight the importance of conserving existing salt marshes and restoring degraded areas to strengthen coastal carbon sinks. Our approach provides a scalable framework for monitoring spatially explicit SOC changes and supports the integration of salt marshes into national carbon management and broader blue carbon strategies. Net salt marsh expansion enhanced surface soil organic carbon, mainly through conversion of aquaculture ponds, agricultural land and seawater areas, despite spatial and temporal variability, based on remote sensing and machine learning analysis of land use and land cover data from China.

Abstract Plant functional traits offer a mechanistic framework for understanding how plant communities respond to environmental change and shape ecosystem functioning. However, despite rapid advances over the past decades, the role of functional traits in driving wetland ecosystem functioning remains less well understood than in terrestrial systems, thereby limiting effective wetland conservation and restoration. In this review, we synthesize existing evidence on how plant functional traits and functional diversity influence key wetland ecosystem functioning, such as productivity, carbon cycling and nutrient cycling. We find that functional traits are key regulators of ecosystem functioning; therefore, targeted restoration should prioritize species with specific traits. We also call for coordinated actions across local and landscape scales to manage potential trade-offs among restoration objectives and enhance ecosystem multifunctionality. Clarifying the roles of functional diversity and wetland-specific flooding-adaptive traits in driving ecosystem functioning is identified as an important focus for future work. Moreover, a deeper understanding of how functional traits and diversity regulate wetland ecosystem functioning requires more manipulative experiments. This review highlights the role of plant traits in mechanistically linking vegetation dynamics to ecosystem functioning in wetlands.

Flash droughts (FDs) develop rapidly and can strongly affect ecosystem functioning and water resources. However, their spatiotemporal variability in China and their effects on diverse ecosystems remain poorly characterized. In this study, the frequency of FD events during the growing season in China from 2001 to 2023 and their key driving interaction mechanisms were systematically analyzed. Using multisource remote-sensing indicators, including the leaf area index, potential evapotranspiration, and gross primary productivity, we quantitatively assessed response timing and impact intensity across different ecosystems. Furthermore, we projected future FD changes in China for 2000–2100 under different climate scenarios. The results reveal that FD frequency varies across different ecosystems in China, with the highest occurrence in humid regions (mean = 6.98 events) and the lowest in arid regions (6.13). Driver analysis indicates that drought risk increases notably under high temperatures and low precipitation. Furthermore, soil moisture dynamics exhibit a two-phase evolutionary pattern of “rapid depletion followed by differential recovery”, whereas ecosystem indicators demonstrate a “transient enhancement followed by persistent decline” response pattern. Compared to arid regions dominated by short vegetation, humid-forest ecosystems exhibit faster response times and greater intensity reactions to FD. The Coupled Model Intercomparison Project Phase 6 (CMIP6) multimodel ensemble projections indicate the most severe future conditions under the RCP5-8.5 scenario. These findings underscore how climate change threatens vegetation ecosystem stability and highlight the urgent need for effective mitigation policies and sustainable management strategies to protect terrestrial vegetation ecosystems.

Wetlands constitute a major global carbon sink and play a pivotal role in climate change mitigation. While data syntheses, modeling studies, and manipulative experiments consistently show high variability in soil organic carbon (SOC) under changing hydrological regimes, long-term field-based evidence from natural wetlands is still lacking. Here, we conducted a decade-long in-situ observation in the Poyang Lake wetland, China, to assess the influence of hydrologic variability on SOC and to elucidate the underlying mechanisms. Results showed that hydrological conditions emerged as the key driver of SOC variation, accounting for 66.07% of the variance, compared with 19.46% explained by climate and 14.47% by soil properties. Hydrological regimes characterized by shortened flooding duration, increased water-level fluctuation, and drier soil conditions were associated with accelerated SOC loss. Structural equation modeling revealed that hydrological variability indirectly regulated SOC via plant-microbial pathways, with microbial carbon use efficiency and oxidase acting as important mediators. Moreover, SOC in mid-elevation wetlands proved vulnerable to changing hydrological conditions, highlighting an elevation-dependent response. Overall, these findings provide robust empirical evidence that hydrological variability is the dominant regulator of wetland SOC dynamics, offering critical insights for refining carbon-climate feedback predictions and informing hydrology-based wetland management strategies.

Salt marshes produce substantial amounts of plant litter, playing a vital role in the long-term accumulation of soil organic carbon. However, the influences of plant litter on soil respiration in salt marshes remain largely unclear, especially when global salt marshes are threatened by plant invasion. We conducted a field experiment to examine how litter removal impacts soil respiration through soil physicochemical properties (temperature, moisture, pH, salinity, inorganic nitrogen, organic carbon) and plant growth (height, density, aboveground biomass) in native Phragmites australis and exotic Spartina alterniflora salt marshes. The results indicated that litter removal had contrasting effects on soil respiration in the before and after S . alterniflora invasion. In P. australis marshes, litter removal decreased soil respiration by 38.3% due to increased soil salinity, while in S . alterniflora , it enhanced soil respiration by 25.9% through increased AGB. Although the litter removal can affect level of soil inorganic nitrogen, pH and organic carbon, these are not the main factors that alter soil respiration. The study highlights that plant litter plays a crucial role in driving Rs in salt marshes, and the processes change with plant invasion. In the future, to accurately predict the carbon cycle process of salt marshes, it is necessary to comprehensively consider the complex relationships among vegetation types, litter, and soil properties.

Wetlands, among Earth's most carbon-dense ecosystems, are vital for climate change mitigation. While plant diversity has been widely shown to increase soil carbon storage in terrestrial ecosystems, its influence in natural wetlands remains unclear. Here, using data from 1,268 natural wetlands surveyed in the US National Wetland Condition Assessment (NWCA), we examined how trait-based plant diversity (functional diversity) and composition (functional identity) affect soil carbon storage. We show that functional diversity had a minimal effect on carbon stocks, and its influence was weakened by elevated soil nutrient availability and non-native plant stress. In contrast, soil carbon storage was generally greater in wetlands dominated by larger, slow-growing and highly hydrophytic plants. Moreover, the benefits of functional identity were contingent on higher water levels and lower human disturbance. These findings suggest that the conservation and restoration of wetlands dominated by large, conservative and hydrophytic species under hydric conditions could help achieve climate change mitigation goals.

Soil carbon greenhouse gas (GHG) emissions are integral to climate security worldwide. Global change is known to impact soil GHG emissions; yet, the contribution of an increasing number of global change factors (GCFs) to the rates of carbon GHG emissions remains virtually unknown, challenging our capacity to forecast the trajectory of climate change. Here, we synthesize 1803 observations on soil CO 2 and CH 4 fluxes across 21 types of GCFs spanning a wide range of ecosystems (i.e., forests, grasslands, farmland, wetlands, tundras, and deserts) and found that an increasing number of GCFs will result in significant increases in CO 2 and CH 4 emissions. The impacts of GCFs on GHG emissions were largely explained by climate, biome types, and GCF-induced changes in soil moisture, providing potential tools for managing global change. Our work provides critical insights, emphasizing that the number of global change stressors needs to be immediately reduced to help minimize the negative impacts of carbon greenhouse gas emissions on climate change.

Changes in the distribution of soil organic carbon (SOC) fractions - particulate organic carbon (POC; unprotected carbon) vs. mineral-associated organic carbon (MAOC; protected carbon) - affect SOC storage and stability. Here, we compile a SOC fraction dataset from 7219 soil samples across six continents. From 2000 to 2022, POC increases by 21.8% while MAOC decreases by 5.3%, leading to a net gain of 11.0% in SOC storage and a 29.1% increase in the POC/MAOC ratio. However, relative to undisturbed natural ecosystems, SOC declines in planted forests, grazed grasslands, and croplands with management practices such as heavy grazing and conventional tillage, primarily due to rapid declines in POC. Our results highlight that the global increase in SOC is mainly driven by POC, but warn of decreasing SOC stability associated with climate change and human activities. Thus, maintaining soil carbon sinks requires targeted strategies focusing on POC.

The functional trait diversity of plant communities regulates the effects of biodiversity on ecosystem functioning and stability. However, the role of functional trait diversity in explaining ecosystem productivity and stability in natural wetlands remains unclear. Using vegetation data from 1139 sites across U.S. wetlands, we examine the associations of functional diversity (trait dispersion within a community) and functional identity (community-level trait values) of plant size traits and resource economics traits with satellite-derived productivity and temporal stability at continental scales. Community-level plant size shows the strongest association with productivity and stability, which is consistent across different wetland types and levels of anthropogenic disturbance. While functional diversity is generally positively correlated with productivity and stability, these relationships vary substantially across environmental contexts. Notably, weaker correlations are observed under higher levels of anthropogenic disturbances. These findings suggest that wetland conservation and restoration efforts should focus on increasing functional diversity and prioritizing large dominant species to increase productivity and stability.

Ecosystem respiration (ER) is the largest contributor to terrestrial carbon loss. ER responds positively to increasing temperature, so a warming world is hypothesized to lead to additional CO2 release, potentially further exacerbating climate warming. The long-term influence of thermal changes on this carbon-climate feedback, however, remains unresolved. Here, by compiling data from 221 eddy covariance sites worldwide, we observe decreases in the temperature sensitivity and reference respiration rates of ER with increasing mean annual temperature, suggesting that ER adapts to temperature changes. Our results further reveal that thermal adaptation would eliminate 17.91-31.41% of the anticipated increase in the respiration of unadapted ecosystems under future warming scenarios, equivalent to a net carbon loss of 0.85-11.83 Pg C per year. The increase in respiration rates of terrestrial ecosystems in response to climate warming may thus be lower than predicted, with important consequences for modulating future terrestrial carbon-climate feedback.

While the alerting effects of microbe-induced plant volatiles (MIPVs) to biotic stressors have been extensively studied, the ecological functions of MIPVs responding to abiotic stressors have received less attention. Using an interplant communication assay setup, we employed Phytolacca americana as a study species to investigate whether heavy metal-induced MIPVs released by the emitter plants contribute to metal tolerance in neighboring receiver plants. We found that high levels of manganese (Mn) stress increased the total MIPV emissions of plants cultivated in non-sterilized soil, in contrast to volatile organic compounds emitted by plants in sterilized soil. MIPVs produced by the Mn-stressed plants notably altered the hormonal profiles of the receiver plants, leading to increased similarity in soil microbial assembles and modification of competitive, stress-tolerant, ruderal strategies. Consequently, the receiver plants exhibited enhanced tolerance to subsequent Mn stress, as evidenced by improved growth performance, increased antioxidant enzyme activities and reduced membrane damage. By unraveling the mechanism underlying MIPV-mediated tolerance priming for neighboring plants, we reveal a key signal role of soil microorganisms involved in plant-plant communication. This study represents one of the initial efforts to elucidate the alerting effects of MIPVs induced by heavy metal stress on neighboring plants and its ecological consequences.