Ye Zhang, Yixue Hong, Xibin Sun, Weina Jia, Hao Chen
2026, 19 (4): rtaf223.
Extreme drought events are projected to increase in frequency and severity, posing serious threats to the stability of forest ecosystems. Forest drought resilience—an essential indicator of ecosystem stability and carbon sequestration potential under climate change—remains poorly understood in terms of its spatial distribution and variation across plant functional types. Here, we assessed global patterns and underlying drivers of forest drought resilience across latitudinal gradients, plant functional types (angiosperms vs. gymnosperms), and taxonomic ranks, using generalized linear models that integrate 282 tree-ring chronologies with satellite environmental and biotic data. Results showed that high-latitude forests had significantly lower drought resilience than those in mid- and low-latitude regions, primarily due to the combined constraints of limited water availability and low temperature. Angiosperm-dominated forests exhibited higher drought resilience than gymnosperm-dominated forests, with the former mainly driven by nutrients and heat, but the latter more constrained by water availability and species diversity. Forest drought resilience also differed among specific taxonomic ranks. Notably, the angiosperm genus Quercus exhibited high drought resilience, while some gymnosperm genera, such as Tsuga and Juniperus, also demonstrated strong drought tolerance through distinct physiological and morphological adaptations. These findings reveal that forest drought resilience is jointly shaped by climatic constraints and biotic traits, with clear latitudinal and phylogenetic differences. Recognizing these patterns can inform region-specific forest management and conservation strategies aimed at enhancing ecosystem stability under intensifying climate change.
Hao Liu, Lijuan Cui, Wei Li, Guangxuan Han, Jihua Wu, Bo Li, Ming Nie
2026, 19 (4): rtag125.
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.
Plant functional traits provide a mechanistic basis for linking vegetation dynamics to ecosystem functioning. This review summarizes the important roles of functional traits and functional diversity in regulating wetland productivity, carbon cycling, and nutrient cycling, and provides guidance for wetland conservation and restoration from local to landscape scales. Current research remains limited by insufficient experimental evidence and the narrow coverage of traits and ecosystem functions. Future studies should further strengthen the mechanistic understanding of how functional traits regulate wetland ecosystem functioning.
He Lyu, Xue-Qian Zhang, Jian Su, Ming-Kai Jiang
2026, 19 (4): rtag033.
Anthropogenic global change profoundly affects terrestrial ecosystem structure and function, creating an urgent and persistent need to accurately predict future ecosystem states. Field-based manipulative experiments provide critical mechanistic insights into these impacts but are inherently limited in spatio-temporal scope. Conversely, process-based models can extrapolate to broader scales but often contain simplified or unrealistic mechanisms that lead to uncertain projections. Data-model integration has emerged as an essential approach to bridging this gap, testing model assumptions against empirical evidence and guiding experimental design via model-based hypotheses. This review synthesized progress in integrating manipulative experiments with process-based models across three key global change drivers: elevated CO2, climate change (warming and altered rainfall) and nutrient manipulation. We demonstrated how this integration reduced key uncertainties in processes such as photosynthesis, carbon-nutrient coupling and soil biogeochemistry, whilst exposing persistent gaps in plant hydraulics, microbial dynamics and multifactorial stresses. These advances were most pronounced in representing CO2 fertilization effects, including improved stomatal optimization theory, dynamic carbon allocation schemes and coupled carbon-nitrogen-phosphorus cycling. By contrast, its application to warming, rainfall change and multi-nutrient interactions remained underdeveloped. To catalyze future progress, we propose specific strategies to foster a more synergistic cycle of knowledge co-production. These include prioritizing the quantification of mechanism-specific data to develop dynamic model formulations, systematically using multi-site experimental networks to benchmark and refine model processes across scales, and strategically employing models to design targeted experiments. Ultimately, these strategies are indispensable for developing more realistic models and achieving predictive understanding of ecosystem responses to global change.
This review synthesizes advances in integrating global change manipulative experiments with process-based models, identifies persistent knowledge gaps in key ecological processes, and proposes targeted strategies to improve predictive understanding of terrestrial ecosystem responses to global change.
Yanze Ma, Rong Cao, Evgenios Agathokleous, Yansen Xu, Longxin He, Zhaozhong Feng
2026, 19 (4): rtag083.
Tropospheric ozone (O3) is a major air pollutant that threatens wheat production. However, the mechanisms underlying cultivar-specific responses remain unclear, particularly how stomatal traits and leaf structural characteristics contribute to differences in O3 sensitivity among cultivars. A field experiment was conducted using 13 winter wheat (Triticum aestivum L.) cultivars exposed to ambient (A-O3) or elevated (E-O3, 1.5 times A-O3) O3 treatment in a Free-Air O3-Concentration Enrichment system (O3-FACE). Elevated O3 significantly increased stomatal density on both adaxial and abaxial leaf surfaces, with a stronger response on the adaxial side, indicating independent regulation between surfaces. At the anthesis stage, stomatal and pore width significantly increased under E-O3, whereas their length was not affected. Elevated O3 significantly reduced adaxial epidermal thickness, abaxial epidermal thickness, mesophyll tissue thickness, and total leaf thickness during grain filling, with significant O3 × cultivar interactions for all traits except abaxial epidermal thickness. Cultivars were classified into sensitive, intermediate, and tolerant groups. Sensitive cultivars exhibited significant reductions in leaf structure, whereas tolerant cultivars largely maintained or even enhanced structural integrity. Overall, cultivar sensitivity to O3 was not directly associated with stomatal traits but rather with the ability to preserve leaf anatomy. These findings suggest that maintaining flag leaf structure is critical for improving wheat resilience to rising O3 levels.
This study demonstrates that wheat cultivar sensitivity to O3 is primarily determined by the capacity to maintain leaf anatomical integrity, providing a mechanistic basis for selecting O3-tolerant cultivars.
Yi Zhu, Yunzhuo Wen, Lu Bai, Guodong Han, Jinglei Tang, Zijian Ye, Zhiqiang Qu, Guijie Zhang, Haiyan Ren
2026, 19 (4): rtag088.
Plant-microbe interactions are strongly influenced by global environmental change, but bacterial responses in diversity, assembly and cross-interface connectivity across multiple plant-soil interfaces remain poorly understood. Here, we investigated bacterial communitiated interface-specific responses in bacterial community structure, assembly processes and the contributions of different interfaces to leaf endophytic bacterial communities. We found that interface identity plays the dominant role in shaping bacterial phylogenetic α- and β-diversity, with soil communities exhibiting higher diversity than phyllosphere communities. Nitrogen addition significantly reduced phylogenetic α-diversity and resulted in a more stochastic phylogenetic structure in bulk soil, whereas warming enhanced phylogenetic clustering in rhizosphere soil. Notably, warming increased phylogenetic dispersion and β- diversity of leaf epiphytic bacteria but decreased β-diversity in rhizosphere soil, indicating contrasting above- and belowground responses. Community assembly across interfaces was dominated by homogeneous selection, with stochastic processes contributing in an interface-dependent manner. Leaf endophytic communities remained remarkably stable, suggesting strong host filtering. Microbial source tracking revealed that warming and N addition increased soil-derived contributions to leaf endophytes, with over 70% of the community originating from soil under global change treatments. Overall, our results demonstrate that long-term warming and N addition drive interface-specific bacterial assembly and enhance soil to leaf microbial connectivity, highlighting the importance of a multi-interface perspective in understanding microbial responses to global change.
Global change may reshape bacterial communities across plant–soil interfaces in dryland grasslands. Based on an 18-year field manipulative experiment, this study shows that long-term warming and nitrogen addition exert interface-dependent effects on plant-soil bacterial communities in a desert steppe. Soil bacterial communities are more sensitive to these global change drivers, whereas leaf-associated communities, particularly leaf endophytes, remain comparatively buffered and strongly regulated by host filtering. Meanwhile, warming and nitrogen addition enhance soil-to-leaf microbial connectivity, highlighting the importance of a multi-interface perspective for understanding microbial responses to global change.
Wenying Wang, Yuanming Xiao, Guoying Zhou, Xiaoyun Wang, Bo Fan, Jiaxin Xu
2026, 19 (4): rtaf198.
Root exudates play a crucial role in the communication and interaction between plants and soil. However, the responses of carbon (C), nitrogen (N) and phosphorus (P) exudation rates and their stoichiometric ratios to multifunctional group species reseeding in severely degraded alpine meadows remain poorly understood. This study was conducted in a severely degraded alpine meadow and four species composition treatments were established: grass mixtures, grass + legume mixtures, grass + legume + sedge mixtures and grass + legume + forb mixtures. The results showed that among the four reseeding treatments, the grass + legume + sedge mixture exhibited the lowest root C exudate rate and total exudate capacity, while N and P exudation rates, as well as their total exudate capacities, did not differ significantly between treatments. The carbon-to-phosphorus (C:P) ratio of root exudate was lowest in the grass + legume + sedge mixture, while the carbon-to-nitrogen (C:N) and nitrogen-to-phosphorus (N:P) ratios showed no significant differences among the four reseeding treatments. Root C and P exudation rates, as well as the C:N and N:P ratios, were significantly correlated with plant diversity, aboveground biomass, total biomass, soil organic matter and electrical conductivity. Variation partitioning analysis showed that root C exudate rate was most strongly influenced by biomass, whereas N and P exudate rates were more strongly affected by plant diversity. These findings suggest that species reseeding patterns significantly influence root exudates and their stoichiometric characteristics and contribute to understand the trajectories of soil microbes and soil health under reseeding.
This study investigates severely degraded alpine meadows. By analyzing the carbon, nitrogen, and phosphorus secretion rates in root exudates, along with their stoichiometric characteristics, we found that mixed sowing treatments led to a reduction in community-level root carbon and phosphorus secretion rates, as well as a decrease in the carbon-to-nitrogen ratio. This reduction can be attributed to enhanced microenvironments and increased interspecific competition. These findings are crucial for understanding the soil ecological processes mediated by root exudates during the restoration of degraded alpine meadows on the Qinghai-Tibet Plateau.
Xiuzhen Shi, Yaqi Shao, Zhijie Yang, Francis Q. Brearley, Manuel Esteban Lucas-Borja, Ding Feng, Yajun Shao, Jianqing Wang
2026, 19 (4): rtag003.
Nitrification is a crucial biogeochemical process that regulates soil inorganic nitrogen forms and triggers soil nitrogen losses. While the prevailing paradigm focuses on the role of functional microbial guilds that drive soil nitrification, a clear mechanistic link between tree species and soil nitrification remains to be established in forest ecosystems. With a common garden experiment, we examined the impacts of the leaf economics spectrum, tree phenology, and symbiotic fungal associations on soil nitrification across 12 subtropical tree species in January and September. Our results revealed that soil potential nitrification rates, ranging from -2.13 to 1.96 mg N kg-1 d-1, varied among different tree species. Liquidambar formosana exhibited the highest soil nitrification rate, while Lindera communis and Elaeocarpus decipiens had the lowest soil nitrification rates at both sampling times. Leaf traits were stronger predictors of soil nitrification than soil variables. In particular, acquisitive tree species characterized by greater specific leaf area and lower leaf dry matter content significantly promoted soil nitrification. Deciduous tree species exhibited significantly higher soil potential nitrification rates than those of evergreen tree species. Structural equation models showed that the leaf economics spectrum positively affected litter N content, which in turn increased soil ammonium availability and subsequently promoted ammonia-oxidizing archaeal abundance, ultimately facilitating soil nitrification. Taken together, our study demonstrates a leaf trait-based framework for linking tree species to ecological processes and emphasizes that the choice of tree species based on the leaf economics spectrum plays a vital role in predicting ecosystem functioning.
Our study reveals that the leaf economics spectrum facilitates soil nitrification via cascading effects on litter N content, soil ammonium availability, and ammonia-oxidizing archaea abundance, and establishes a leaf trait-based framework for linking tree species to ecological processes.
Xingyun Huang, Fangyuan Guan, Zhe Lu, Guoming Qin, Yongxing Cui, Tao Li, Evans Asenso, Ruichang Shen, Benjamin J. Wainwright, Jingwei Shi, Lulu Zhang, Hui Li, Jingfan Zhang, Jinge Zhou, Ruyi Ding, Hua He, Faming Wang
2026, 19 (4): rtaf230.
While mangrove restoration has a great potential for enhancing soil organic carbon (SOC) sequestration in coastal wetlands, microbial-mediated SOC decomposition introduces huge uncertainty to this process. Microbial carbon use efficiency (CUE) is a crucial trait for microorganisms controlling SOC turnover, but how mangrove restoration could affect microbial CUE remains unclear. Here, we investigated the effects of mangrove restoration on microbial CUE in a typical restored mangrove wetland and further explored its connection to microbial necromass carbon (MNC) content. Our results revealed mangrove restoration increased microbial CUE by 37.84%–56.76% due to an increase in organic carbon quality and a shift in microbial community structure from fast-growing r-strategist (bacteria-dominated including Proteobacteria and Bacteroidota) to slow-growing K-strategist (fungal taxa and bacterial phyla such as Actinobacteriota, Acidobacteriota, and Chloroflexi). Microbial CUE was also positively correlated with MNC, explaining 73% and 69% variations in fungal and bacterial necromass C, respectively. These findings indicate that mangrove restoration enhances SOC sequestration not only through increased plant-derived carbon input but also by elevating microbial CUE and promoting MNC accumulation. Although bacterial necromass carbon showed a higher percentage increase, fungal necromass constituted the dominant portion of the accrued microbial-derived carbon pool, underscoring the critical role of fungal communities in the formation of stable SOC. Our study highlights the significant role of microbial processes in promoting SOC accumulation during mangrove restoration. These results emphasize the importance of incorporating microbial processes into coastal wetland restoration strategies to maximize C sequestration.
Mangrove restoration significantly enhances microbial carbon use efficiency and promotes microbial necromass carbon accumulation by improving organic carbon quality and driving a shift in microbial community from r-strategists to K-strategists. These findings highlight the importance of incorporating microbial processes into restoration strategies to maximize soil organic carbon sequestration in coastal wetlands.
Danielle Begley-Miller, Duane R. Diefenbach, Marc E. McDill, Patrick J. Drohan, Autumn E. Sabo, Justin Zweck, Christopher S. Rosenberry, Bret D. Wallingford, Emily J. Domoto
2026, 19 (4): rtaf225.
In eastern North America, cucumber-root (Medeola virginiana) is a widely distributed perennial forest herb that has been used as an ecological indicator of white-tailed deer (Odocoileus virginiana) browsing due to its predictable responses to deer exclusion (i.e. increased height, abundance). However, cucumber-root is less likely to occupy sites with high concentrations of soil manganese (Mn), which may limit its utility as an indicator under limiting soil conditions. We examined responses of cucumber-root total counts and flowering abundance to deer exclusion, competitive release from surrounding vegetation, and soil application of dolomitic limestone to determine the relative effects of these treatments over 7 years (2014–2021). Prior to treatment, initial total and flowering abundance were best explained by soil extractable Mn concentration. Post-treatment, fencing best explained increases in total counts, but flowering abundance was most affected by soil extractable Mn and pH. Initial soil Mn concentrations determined the effectiveness of dolomitic limestone application; microplots with moderate to high soil Mn (>6 cmolc kg-1) had increased flowering with increased pH, while flowering decreased on microplots with initially low soil Mn concentrations (<6 cmolc kg-1). We suspect changes to soil chemistry from liming affected plant stress, but that stress was either alleviated or intensified depending on initial soil Mn concentrations. Herbivory is an important driver of plant abundance across our study area but flowering response, a critical component of plant demography, seems to be driven by soil Mn. Cucumber-root may have limited utility as an indicator because soil chemistry mediates flowering responses to deer exclusion.
Cucumber-root (Medeola virginiana) has been used as an ecological indicator of white-tailed deer (Odocoileus virginiana) herbivory due to its wide geographic distribution and seemingly predictable responses to deer exclusion. We found that in addition to herbivory, cucumber-root was negatively affected by high levels of soil Mn, which may limit its utility as an indicator of deer impact on sites with limiting soil conditions. Applied soil amendments of dolomitic limestone to improve soil conditions did not consistently increase abundance or flowering. Liming was only beneficial when soil Mn was high and likely phytotoxic, further supporting the importance of Mn in influencing the abundance and distribution of cucumber-root.