Functional traits are widely used to predict species redistribution under climate change because traits determine how plants interact with the environment and shape population dynamics, which ultimately drive range shifts. However, traits still have limited ability to predict range shifts, as the pathways linking traits to demographic processes and subsequently to range shifts are poorly understood. Using 15 years of forest census data for 74 tree species and key functional traits representing distinct ecological strategies (e.g., specific leaf area and wood density), we found that tree elevational range shifts were driven primarily by recruitment rather than mortality. Functional traits influenced range shifts through specific pathways: species with higher structural investment (e.g., high wood density) exhibited higher recruitment rates at upper elevations and shifted upward, whereas resource acquisition traits (e.g., specific leaf area) directly accelerated the upward shift of range centers. Our findings demonstrated the complex pathways that traits mediate tree range shifts and highlight recruitment as the crucial process for improving trait-based predictions of tree range shifts. Ultimately, our framework provides forest managers with an actionable, trait-based tool to guide species selection, assisted migration, and proactive conservation in warming climates.

The global decrease in species diversity from low to high latitudes is among the most robust biogeographic patterns1,2. There is continuing debate on the contribution of conspecific negative density dependence (CNDD) to the latitudinal diversity gradient evident for trees3,4. Theory suggests that CNDD based on pairwise interactions alone is not sufficient to explain the intricacies of diverse communities, because higher-order interactions (HOIs) may greatly modify these interactions5,6. However, there has been a lack of empirical studies investigating how HOIs intertwine with pairwise interactions and how they may contribute to the latitudinal tree diversity gradient. Here we examined both pairwise interactions and HOIs across 32 large permanent forest plots, most in the northern hemisphere. We detected evidence of HOIs in 40% of the 1,543 species-plot combinations for tree growth, and 23% of the 1,340 such combinations for tree survival, with the strength of these interactions declining with latitude. HOIs were found to benefit rare species but disadvantage common species, suggesting a potential mechanism promoting species diversity. This stabilizing effect weakened towards higher latitudes, consistent with the latitudinal tree diversity gradient. Our findings reveal an important interplay between pairwise interactions and HOIs in promoting the latitudinal tree diversity gradient and help to clarify the contribution of CNDD to this biogeographic pattern.

Climate change is exacerbating tree mortality worldwide, threatening the stability of forest soil organic carbon (SOC) stocks. However, how SOC responds to tree mortality amid co-occurring disturbances remains mechanistically unresolved. Here, we demonstrate that topography spatially decouples the canopy-opening and detrital-legacy effects of tree mortality and transforms these co-occurring disturbances into distinct selective pressures on soil microbial communities, thereby driving SOC toward contrasting fates through divergent microbial strategies for carbon and energy acquisition. On ridges, canopy-opening effects co-select for exo-enzyme and aerobic-respiration traits, alongside SOC loss associated with reduced heavy-fraction organic carbon. In valleys, detrital-legacy effects promote light-fraction-associated SOC gain while co-enriching endo-enzyme and anaerobic-respiration traits, potentially strengthening SOC retention. By integrating amplicon sequencing with genome-informed functional traits, our study provides genomic evidence for the microbial mechanisms underlying divergent SOC responses to tree mortality and highlights the potential of genome-based microbial traits for predicting ecosystem-scale biogeochemical processes. Topography spatially decouples the canopy-opening and detrital-legacy effects of tree mortality, creating distinct pressures on soil microbes that drive soil carbon toward contrasting fates through divergent microbial strategies.

Abstract Population stability (PS) of functionally important species underpins ecosystem resilience, yet the mechanisms that maintain PS under heterogeneous nitrogen (N) conditions remain elusive, particularly for legumes in (sub)tropical forests. Legumes can stabilize their population performance through high abundance or symbiotic N2 fixation, but how soil N “chooses” between these strategies is unknown. In a 20-ha subtropical forest plot, the sole dominant legume Ormosia glaberrima, with >2,500 individuals recorded over 15 years, provides an ideal system to test these pathways. We quantified PS from long-term demography as the inverse of inter-period variation in basal area growth, and assessed biological N fixation (BNF) ability using the N stable isotope natural abundance method. Structural equation modeling (SEM) was applied to disentangle the direct and indirect effects of soil N, abundance, and BNF ability on PS. Results showed no significant direct effect of soil N on the PS of O. glaberrima. Instead, it was positively correlated with abundance (R2adj =0.22, P < 0.001) and negatively related to BNF ability (R2adj =0.26, P < 0.001). SEM explained 34% of the variation in PS and revealed opposing mediating pathways. Elevated soil N indirectly enhanced PS by increasing abundance (β = 0.27) but reduced PS by suppressing BNF ability (β = -0.15). These findings reveal a context-dependent “abundance-fixation trade-off” as a novel mechanism regulating long-term legume population performance, with important implications for forest management aimed at maintaining ecosystem stability under global N deposition.

The search for simple principles that underlie the spatial structure and dynamics of plant communities is a long-standing challenge in ecology1–6. In particular, the relationship between species coexistence and the spatial distribution of plants is challenging to resolve in species-rich communities7–9. Here we present a comprehensive analysis of the spatial patterns of 720 tree species in 21 large forest plots and their consequences for species coexistence. We show that species with low abundance tend to be more spatially aggregated than more abundant species. Moreover, there is a latitudinal gradient in the strength of this negative aggregation–abundance relationship that increases from tropical to temperate forests. We suggest, in line with recent work10, that latitudinal gradients in animal seed dispersal11 and mycorrhizal associations12–14 may jointly generate this pattern. By integrating the observed spatial patterns into population models8, we derive the conditions under which species can invade from low abundance in terms of spatial patterns, demography, niche overlap and immigration. Evaluation of the spatial-invasion condition for the 720 tree species analysed suggests that temperate and tropical forests both meet the invasion criterion to a similar extent but through contrasting strategies conditioned by their spatial patterns. Our approach opens up new avenues for the integration of observed spatial patterns into ecological theory and underscores the need to understand the interaction among spatial patterns at the neighbourhood scale and multiple ecological processes in greater detail. A unified framework is presented that integrates observed spatial patterns of individual trees in forests with ecological processes into a novel coexistence theory.

The size, number, and distribution of forest canopy gaps vary significantly across spatial scales, yet their relationships with underlying drivers, such as large trees, topography, and soil properties, remain insufficiently comprehended. We utilized an unmanned aerial vehicle to measure forest gap patterns (size, number, and aggregation) at seven spatial scales (20-400 m) in four subtropical forests and quantified the effect of large trees, topography, and soil in shaping gap patterns using ground inventory data. Gap size and aggregation showed significant variation across scales. Large trees and topographic complexity were major factors of gap patterns, with their effects depending on scale. Large trees in two forests had a significantly negative effect on gap size and density at the 20-m scale, but this effect was weaker and positive at the 100-m scale. Topography had the strongest effect on gap aggregation at a small scale (20 m) and on gap size and density at a larger scale (100 m). These results underscore the importance of spatial scale in understanding forest dynamics and highlight how community-level factors shape canopy structure. Identifying scale-dependent drivers of gap patterns can inform gap-based restoration and conservation strategies. Forest managers can reduce gap clustering by protecting large trees, especially in wind-prone areas, helping to maintain canopy structure, promote species diversity, and enhance ecosystem resilience.

Abstract The functional basis of tree growth is often evaluated based on trunk diameter even though diameter is only one dimension of growth that may not be an integrative measure of resource allocation. We tested the hypothesis that growth—functional trait relationships are stronger when key sources of variation in tree growth are also accounted for, namely tree height and DBH, as well as size‐related variation in wood density and seed production using data from 3881 trees of 24 species in a subtropical forest using ordinary least square regression and standard major axis regression. Wood density varied with tree size for 14 of 24 species, generally increasing with size. For 18 of 24 species, the correlations of leaf mass per area and an index of photosynthetic investment (PI) with biomass growth was stronger than with diameter growth rate. Juveniles did not show stronger relationships than adults but biomass growth adding up with seed production showed stronger relationships with PI than biomass growth alone for three of eight species. Synthesis. Thus, our study helps resolve a paradox of trait‐based ecology, that is, weak growth—trait relationships, as stronger relationships emerged when accounting for more sources of intraspecific, among‐tree variation in resource allocation.

Host specialization plays a critical role in the ecology and evolution of plant-microbe symbiosis. Theory predicts that host specialization is associated with microbial genome streamlining and is influenced by the abundance of host species, both of which can vary across latitudes, leading to a latitudinal gradient in host specificity. Here, we quantified the host specificity and composition of plant-bacteria symbioses on leaves across 329 tree species spanning a latitudinal gradient. Our analysis revealed a predominance of host-specialized leaf bacteria. The degree of host specificity was negatively correlated with bacterial genome size and the local abundance of host plants. Additionally, we found an increased host specificity at lower latitudes, aligning with the high prevalence of small bacterial genomes and rare host species in the tropics. These findings underscore the importance of genome streamlining and host abundance in the evolution of host specificity in plant-associated bacteria along the latitudinal gradient. Our study provided empirical evidence for three fundamental predictions regarding the mechanisms of host specialization in plant-bacteria symbiosis, by a comprehensive assessment of the host specificity in leaf-associated bacteria along a latitudinal gradient. We revealed negative effects of genome size and host species abundance on the host specificity of leaf bacteria, consistent with the expectation that host specialization is accompanied by genome streamlining and is influenced by host abundance. Additionally, we demonstrated an increased host specificity at lower latitudes, in line with the decreased bacterial genome size and increased prevalence of rare host species in the tropics. These findings highlighted the interplay among host specificity, genome streamlining and host plant abundance in driving the latitudinal diversity gradient of plant-bacteria symbioses.image

Accurately estimating leaf functional traits across different species and canopy layers in subtropical evergreen broad-leaf forests remains a significant challenge due to the complexity of canopy structures and spectral noise. Although hyperspectral remote sensing holds substantial promise, existing methods struggle to deliver robust models capable of generalizing across diverse species and environmental conditions. This study aimed to develop a robust hyperspectral estimation approach for eight leaf traits across six species and three canopy layers, integrating successive projections algorithm (SPA) and random forest (RF) modeling. Utilizing 267 leaf samples and hyperspectral reflectance data acquired via a tower crane in Dinghushan National Nature Reserve, Guangdong Province, China, we demonstrated that the SPA-RF model, when applied to first derivative reflectance (FDR) data, significantly enhanced the accuracy and transferability of leaf trait estimations. The integration of SPA for wavelength selection and RF for modeling represented a robust approach, effectively mitigating the complexities introduced by species diversity and canopy heterogeneity. Leaf trait estimations derived from upper canopy layer samples generally yielded greater precision than those from lower and middle layers. Furthermore, species adapted to high-light environments (sun-tolerant) offered more accurate estimations than those adapted to low-light conditions (shade-tolerant). Among the eight leaf traits studied, flavonoid content, nitrogen balance index, and SPAD (relative leaf chlorophyll content) values emerged as more reliably estimated compared to carbon, nitrogen, phosphorus, equivalent water thickness, and specific leaf area. These findings illuminate the influence of canopy layer and species-specific traits on the precision of leaf trait estimations using hyperspectral remote sensing. The study’s insights emphasize the need for species- and canopy layer-specific approaches in ecological monitoring and conservation efforts.

Recent climate change has been shown to alter aspects of forest plant demography, such as growth and mortality, but less attention has been focused on how climate change alters the reproduction of plant populations through time. We hypothesized that the plant seed production would respond to climate change, and that the response would differ according to plant life form and functional traits. We tested this hypothesis by examining climate change from 2005 to 2020 and by determining the temporal trends of seed rain and seed production from plants with different life forms (e.g., herbs, vines, trees, palms) and of tree species with different statures as well as leaf, seed and wood traits during 2014-2020. We also tested the correlation between meteorological variables and time series of seed rain using cross correlation analysis. We found increasing wetness (lower vapor pressure deficit) through time but with decreasing minimum relative humidity, which is a pattern consistent with trends seen in many other parts of the world. During the study period, seed production of shrubs and relative contribution of woody vines to total seed rain decreased, while relative contribution of palms to total seed rain and tree species with more conservative leaf traits increased their contribution to total seed rain. Overall, these trends were well explained by the trends of meteorological variables and the responses of these life forms to climate change in previous studies. Additionally, the increasingly conservative leaf traits were also consistent with shifts in traits following recovery from disturbance. Our results suggest that a trait-based approach may help to unveil trends that are not readily apparent by examining seed counts alone. The compositional change found in the seed rain may indicate future shifts in forest species composition and should be incorporated into future studies of forest modelling and projections under climate change.

为探讨红树植物光适应的生理生态机制,通过遮荫控制试验对无瓣海桑(Sonneratia apetala)、秋茄(Kandelia candel)、木榄(Bruguiera gymnorrhiza)、桐花树(Aegiceras corniculatum)、老鼠簕(Acanthus ilicifolius)、卤蕨(Acrostichum aureum)、银叶树(Heritiera littoralis)、黄槿(Hibiscus tiliaceus)等8种红树植物的1 a生幼苗在不同生长光强(自然光强的100%、45%、30%、10%)下的叶绿素荧光参数进行了研究.结果表明,8 种红树植物在遮荫后光系统II最大光化学效率(Fv/Fm)和光系统II实际光化学效率(ΦPSII)总体呈上升趋势,而电子传递速率(ETR)则显著下降.无瓣海桑、秋茄、桐花树、银叶树和黄槿在全光照下表现出比其他3种植物更高的Fv/Fm,同时桐花树和银叶树的ΦPSII和ETR也显著高于木榄、老鼠簕和卤蕨.因此,无瓣海桑、秋茄、桐花树、银叶树和黄槿在高光辐射下具有更高的光能利用率,同时桐花树和银叶树能更好地利用高光并耗散过剩光能,适宜作为中上层树种或在郁闭度较低的林下种植.而木榄、老鼠簕和卤蕨在高光辐射下ΦPSII值均不足 0.2,ETR也仅为无瓣海桑等阳生物种的20%～33%,更适宜在光照条件较弱的林下种植.

Predicting and managing the structure and function of plant microbiomes requires quantitative understanding of community assembly and predictive models of spatial distributions at broad geographic scales. Here, we quantified the relative contribution of abiotic and biotic factors to the assembly of phyllosphere bacterial communities, and developed spatial distribution models for keystone bacterial taxa along a latitudinal gradient, by analyzing 16S rRNA gene sequences from 1453 leaf samples taken from 329 plant species in China. We demonstrated a latitudinal gradient in phyllosphere bacterial diversity and community composition, which was mostly explained by climate and host plant factors. We found that host-related factors were increasingly important in explaining bacterial assembly at higher latitudes while nonhost factors including abiotic environments, spatial proximity and plant neighbors were more important at lower latitudes. We further showed that local plant-bacteria associations were interconnected by hub bacteria taxa to form metacommunity-level networks, and the spatial distribution of these hub taxa was controlled by hosts and spatial factors with varying importance across latitudes. For the first time, we documented a latitude-dependent importance in the driving factors of phyllosphere bacteria assembly and distribution, serving as a baseline for predicting future changes in plant phyllosphere microbiomes under global change and human activities.

The search for simple principles underlying the complex spatial structure and dynamics of plant communities is a long-standing challenge in ecology[1][1]-[6][2]. In particular, the relationship between the spatial distribution of plants and species coexistence is challenging to resolve in species-rich communities[7][3]-[9][4]. Analysing the spatial patterns of tree species in 21 large forest plots, we find that rare species tend to be more spatially aggregated than common species, and a latitudinal gradient in the strength of this negative correlations that increases from tropical to temperate forests. Our analysis suggests that latitudinal gradients in animal seed dispersal[10][5] and mycorrhizal associations[11][6],[12][7],[13][8] may jointly generate this intriguing pattern. To assess the consequences of negative aggregation-abundance correlations for species coexistence, we present here a framework to incorporate the observed spatial patterns into population models[8][9] along with an analytical solution for the local extinction risk[14][10] of species invading from low abundances in dependence of spatial structure, demographic parameters, and immigration. For example, the stabilizing effect of the observed spatial patterns reduced the local extinction risk of species when rare almost by a factor of two. Our approach opens up new avenues for integrating observed spatial patterns into mathematical theory, and our findings demonstrate that spatial patterns, such as species aggregation and segregation, can contribute substantially to coexistence in species-rich communities. This underscores the need to understand the interactions between multiple ecological processes and spatial patterns in greater detail.### Competing Interest StatementThe authors have declared no competing interest. [1]: #ref-1 [2]: #ref-6 [3]: #ref-7 [4]: #ref-9 [5]: #ref-10 [6]: #ref-11 [7]: #ref-12 [8]: #ref-13 [9]: #ref-8 [10]: #ref-14

Mangrove forests have high ecological, social and economic values, but due to environmental changes and human activities, natural mangrove forests have experienced serious degradations and reductions in distribution area worldwide. In the coastal zones of southern China, an introduced mangrove species, Sonneratia apetala, has been extensively used for mangrove restoration because of its rapid growth and strong environmental adaptability. However, little is known about how soil microorganisms vary with the restoration stages of the afforested mangrove forests. Here, we examined the changes in soil physicochemical properties and microbial biomass, community structure and function, and network in three afforested S. apetala forests with restoration time of 7, 12, and 18 years and compared them with a bare flat and a 60-year-old natural Kandelia obovata forest in a mangrove nature reserve. Our results showed that the contents of soil salinity, organic carbon, total nitrogen, ammonium nitrogen, and microbial biomass increased, while soil pH and bacterial alpha diversity decreased with afforestation age. Soil microbial community structure was significantly affected by soil salinity, organic carbon, pH, total nitrogen, ammonium nitrogen, available phosphorus, and available kalium, and susceptibility to environmental factors was more pronounced in bacterial than fungal community structure. The relative abundances of aerobic chemoheterotrophy were significantly higher in 12- and 18-year-old S. apetala than in K. obovata forest, while that of sulfate-reducing bacteria showed a decreasing trend with afforestation age. The abundance of dung saprotroph was significantly higher in 12- and 18-year-old S. apetala forests than in the natural forest. With the increasing afforestation age, the modularity of microbial networks increased, while stability and robustness decreased. Our results suggest that planting S. apetala contributes to improving soil fertility and microbial biomass but may make soil microbial networks more vulnerable.

Diversity-biomass relationships (DBRs) often vary with spatial scale in terrestrial ecosystems, but the mechanisms driving these scale-dependent patterns remain unclear, especially for highly heterogeneous forest ecosystems. This study explores how mutualistic associations between trees and different mycorrhizal fungi, i.e., arbuscular mycorrhizal (AM) vs. ectomycorrhizal (EM) association, modulate scale-dependent DBRs. We hypothesized that in soil-heterogeneous forests with a mixture of AM and EM tree species, (i) AM and EM tree species would respond in contrasting ways (i.e., positively vs. negatively, respectively) to increasing soil fertility, (ii) AM tree dominance would contribute to higher tree diversity and EM tree dominance to greater standing biomass, and that as a result (iii) mycorrhizal associations would exert an overall negative effect on DBRs across spatial scales. To empirically test these hypotheses, we collected detailed tree distribution and soil information (e.g., nitrogen, phosphorus, organic matter, pH) from seven temperate and subtropical AM-EM mixed forest megaplots (16-50 ha). Using a spatial codispersion null model and structural equation modeling, we identified the relationships among AM or EM tree dominance, soil fertility, tree species diversity, and biomass and, thus, DBRs across 0.01- to 1-ha scales. We found the first evidence overall supporting the three aforementioned hypotheses in these AM-EM mixed forests: (i) In most forests, with increasing soil fertility, tree communities changed from EM-dominated to AM-dominated; (ii) increasing AM tree dominance had an overall positive effect on tree diversity and a negative effect on biomass, even after controlling for soil fertility and number of trees. Together, (iii) the changes in mycorrhizal dominance along soil fertility gradients weakened the positive DBR observed at 0.01- to 0.04-ha scales in nearly all forests and drove negative DBRs at 0.25- to 1-ha scales in four out of seven forests. Hence, this study highlights a soil-related mycorrhizal dominance mechanism that could partly explain why, in many natural forests, biodiversity-ecosystem functioning (BEF) relationships shift from positive to negative with increasing spatial scale.

Global environmental changes drive biodiversity loss and community compositional change. Yet whether and how both factors simultaneously impact biomass dynamics in natural ecosystems remains elusive, especially considering their multidimensional effects (e.g., taxonomic, functional, and phylogenetic) over spatial scales. To fill this knowledge gap, we generated an experimental spatial gradient using circular quadrats that vary in radius (2–30 m) in a subtropical forest on Dinghushan Mountain, China. Within each quadrat over 10 years, we calculated the changes in aboveground biomass (i.e., net Δbiomass), biodiversity (i.e., Δbiodiversity for richness, Shannon diversity, functional, phylogenetic), and community composition (i.e., β-diversity for taxonomic, functional, phylogenetic). Based on multi-model inference, we determined the most parsimonious relationships of Δbiomass as a function of Δbiodiversity and β-diversity and then quantified their standardized coefficients in response to the spatial gradient. Our results showed that Δbiomass, Δbiodiversity, and β-diversity decreased with quadrat size; the former at an accelerating rate and the latter at decelerating rates. While Δbiomass as a function of Δbiodiversity and β-diversity had low occurrences across the gradient, Δbiomass was strongly related to the change in functional dispersion (i.e., ΔFDis) and taxonomic β-diversity at larger spatial scales. Our results suggest scale-dependent influences of biodiversity loss and community compositional change on biomass dynamics in natural ecosystems. Further, our results highlight that multiple dimensions of biodiversity should be considered when predicting biomass dynamics at large spatial scales.

The restoration and reconstruction of mangrove wetland ecosystem is one of the key research fields in ecological restoration in the coastal zone of South China. In order to reveal the physiological and ecological strategies to light conditions of mangrove species, the characteristics of leaf soluble protein contents and activities of antioxidant enzymes in seedlings of eight mangrove species (Sonneratia apetala, Kandelia obovata, Bruguiera gymnorhiza, Aegiceras corniculatum, Acanthus ilicifolius, Acrostichum aureum, Heritiera littoralis and Hibiscus tiliaceus) under different light intensity treatments (100%, 45%, 30%, and 10% of natural light intensity) were studied using shading control experiment. The results were as follows: (1) Low light intensities had little effect on the leaf soluble protein contents of Bruguiera gymnorhiza, Acanthus ilicifolius and Acrostichum aureum, whereas the other five species showed a decreasing trend of leaf soluble protein contents with the decline in light intensity. (2) The activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX) in the leaves of Bruguiera gymnorhiza, Acanthus ilicifolius and Acrostichum aureum under 10% of natural light intensity treatment had no significant differences compared with the control, while the other five mangrove species showed a decreasing trend of all the five antioxidant enzyme activities. In conclusion, the results indicate that Bruguiera gymnorhiza, Acanthus ilicifolius and Acrostichum aureum are suitable to be planted under the forest with high canopy density, while Sonneratia apetala, Kandelia obovata, Aegiceras corniculatum, Heritiera littoralis, Hibiscus tiliaceus are suitable to be planted under the forest with lower canopy density or planted as middle and upper layer tree species in mangrove. The results of this study provide theoretical guidance for the optimal allocation of artificial mangrove communities.

Functional traits are good predictors of plant responses and adaptations to ever-changing environments. However, forecasting forest community dynamics is challenging because the relationships among different tree demographic properties (growth, mortality and recruitment) and how functional traits are associated with tree demography remain largely unknown. Here, in a 20-ha subtropical forest permanent plot, we quantified the rates of tree growth, mortality and recruitment across 53 dominant tree species (diameter at breast height; DBH >= 1 cm) from 2005 to 2020. Functional traits that are closely related to plant photosynthesis, nutrients, hydraulics and drought tolerance were measured. We found that tree growth rate (GR) varied independently from rates of tree mortality and recruitment. Hydraulic conductivity was positively correlated with GR (explaining 27% variation-the strongest relationship observed) whereas wood density was negatively correlated with GR. Leaf life span was negatively related to tree mortality. Species with high carbon assimilation rate, nutrient concentration and hydraulic conductivity had high recruitment rates. Leaf turgor loss point was unrelated to plant demography. Principal component analysis revealed that species with quick resource acquisition rates had high rates of growth and recruitment. Our results illustrate that the correlations among tree demographic properties were weak in this subtropical forest with monsoonal climate. Most notably, against expectations, there was no observed trade-off between growth and mortality. Individual functional traits explained up to 27% of each demographic rate. Variation in recruitment rate was aligned with traits indexing the leaf economic spectrum and also plant hydraulic variation. A better understanding of the role of disturbances on trait-demography relationships would help build a deeper and more nuanced understanding of the ecology of subtropical monsoon forests. Read the free Plain Language Summary for this article on the Journal blog.

AbstractIdentifying patterns and drivers of plant community assembly has long been a central issue in ecology. Many studies have explored the above questions using a trait‐based approach; however, there are still unknowns around how patterns of plant functional traits vary with environmental gradients. In this study, the responses of individual and multivariate trait dispersions of 134 species to soil resource availability were examined based on correlational analysis and torus‐translation tests across four spatial scales in a subtropical forest, China. Results indicated that different degrees of soil resource availability had different effects on trait dispersions. Specifically, limited resource (available phosphorus) showed negative relationships with trait dispersions, non‐limited resource (available potassium) showed positive relationships with trait dispersions, and saturated resource (available nitrogen) had no effect on trait dispersions. Moreover, compared with the stem (wood density) and architectural trait (maximum height), we found that leaf functional traits can well reflect the response of plants to nutrient gradients. Lastly, the spatial scale only affected the magnitude but not the direction of the correlations between trait dispersions and environmental gradients. Overall, the results highlight the importance of soil resource availability and spatial scale in understanding how plant functional traits respond to environmental gradients.