Understanding the degree to which the species diversity-productivity relationship (SDPR) is applicable to natural ecosystems-beyond modeling and experimental contexts - is of vital importance for comprehending the consequences of global biodiversity loss on terrestrial ecosystems. Two essential features of natural forests that have not received adequate attention in the SDPR are seasonality and species evenness. Here, we monitor the intraand inter-annual growths of 6,515 trees in a subtropical seasonal (temperature- and rainfall-seasonal) forest over a six-year period. We investigate whether evenness affects forest productivity independently or interacting with richness and how the underlying mechanisms shift with seasonality and soil properties, employing structural equation modeling. Our findings reveal a consistent decline in species diversity, functional diversity and forest productivity from the wet-warm season to the dry-cold season, with community traits shifting from acquisition to conservative strategies. Species richness increases but evenness decreases forest productivity-uneven communities are more productive, and the attenuation effect of evenness on productivity varies slightly across different seasons. Species richness and evenness jointly affect productivity through community-weighted means (CWM) of functional traits in the wet-warm season and through both functional diversity and CWM of functional traits in the dry-cold season, indicating that the mass ratio effect is predominant during the wet-warm season, whereas both niche complementarity and mass ratio effects jointly drive productivity in the dry-cold season. Soil water availability directly affects forest productivity in the wet-warm season and indirectly through CWM of functional traits in the dry-cold season. Our study, the first to elucidate the seasonal dynamics of the SDPR in subtropical forests. Our results highlight species evenness as a key component of species diversity regulating seasonal productivity dynamics in heterogeneous, species-rich natural forests. To enhance forest resilience under climate change (e.g., drought), management should prioritize maintaining moderate evenness, while strategically planting drought-tolerant species and acquisitive species of subtropical forest ecosystems.

Spring phenology is closely linked to plant growth and reproduction and is highly sensitive to environmental changes. For dioecious species, the temporal overlap between female and male flowering is critical for their successful pollination. However, it remains largely unclear whether males and females respond differently to climate change and how this may influence the phenological synchrony between the sexes. By conducting twig experiments, we investigated how the flower and leaf phenology of male and female individuals of a dioecious tree species, Cercidiphyllum japonicum, responded to the changes in temperature and photoperiod. Male individuals flowered and unfolded their leaves earlier than female individuals in most cases, reflecting sexual dimorphism in spring phenology. Elevated temperature significantly advanced the flowering and leaf unfolding in both sexes, while shortened photoperiod had no significant effect on either phenophase. The time interval between flowering and leaf unfolding tended to be shortened under warming in males but not in females. Interestingly, the flowering time of females was more sensitive to temperature than that of males. These findings suggest that spring warming may paradoxically enhance reproductive fitness in this species by reducing the flowering time gap between sexes, highlighting the critical need to consider sex-specific responses when predicting population dynamics under climate change.

Functional traits reflecting leaf structure and functions can show tradeoff or synergetic patterns. How these patterns exert an 'afterlife' effect on litter decomposition, or how such an effect is mediated by soil fauna, remains poorly understood. Here, using litter traits reflecting leaf growth, defence, size and shape, we tested a hypothetical framework addressing (i) the relationships between decomposition rate (k) and trait patterns (growth versus defence, chemical versus structural defence and size versus shape) and (ii) how the access of soil macro- and mesofauna to the litter alters these relationships. We conducted a litterbag decomposition experiment of 18 tree species in subtropical Hunan, China, for 13 months. Litterbags with mesh sizes of 0.07, 2 and 5 mm were used to mimic the cases of (i) excluding meso- and macrofauna, (ii) excluding macrofauna and (iii) including all fauna. For each species, 14 litter traits related to leaf growth and defence and 8 traits related to leaf size and shape were measured. We found a growth-defence space and a size-shape space among species: the former was driven by two orthogonal trait gradients reflecting the tradeoffs between mechanical and chemical defences, and between growth and overall defence, respectively; the latter was driven by two orthogonal trait gradients of size and shape, respectively. Among the four gradients, the defence category gradient spanning species with varying relative investments in mechanical versus chemical defences was the only one showing significant relationships with k, mainly due to the significant relationships between mechanical traits and k. The presence of meso- and macrofauna significantly increased k but could not significantly change the slope of the relationship between k and any of the trait gradients. Synthesis. We reveal that defence-related traits predominate over growth-related or size and shape traits in driving litter decomposition and that soil fauna play a marginal role in modifying such relationships, thereby enhancing our holistic understanding of trait-decomposition relationships. Our findings indicate that the contribution of relative investments in chemical versus mechanical defence to interspecific variation in leaf litter decomposition deserves broad investigation in different ecosystems. 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Herbivory is widely known to play a critical role in structuring plant communities. However, much less is known about what factors determine herbivory in forest ecosystems. Here, we monitored herbivory damage on more than 2000 seedlings in a subtropical forest (2022 and 2023), to identify the key biotic drivers of interspecific variation in seedling herbivory. We found a positive correlation between seedling height and herbivory, evidence for the “plant apparency” hypothesis. Both increasing proportion of herbivory on local conspecifics and conspecific adult density were associated with higher herbivory on focal seedlings, evidence for the Janzen-Connell hypothesis. Interestingly, interactions with ants, as an example of interspecific mutualisms, were found to increase herbivory damage, while decrease seedling mortality in the same research system, highlighting the pivotal role of biotic mutualisms in mediating plant-herbivore interactions. Furthermore, leaf functional traits accounted for the greatest proportion of variance in seedling herbivory, indicating that they served as the primary determinant regulating herbivory pressure at the seedling stage. Overall, our study provides insight into the intricate interplay of seedling height, Janzen-Connell effect and functional traits in determining seedling herbivory and consequently assembly of forest ecosystems. These findings advance our understanding of subtropical forest community dynamics and provide empirical support for evidence-based conservation strategies in such ecosystems.

Arbuscular mycorrhizal (AM) and ectomycorrhizal (EcM) fungi and their associated trees employ contrasting nutrient acquisition strategies, strongly impacting soil carbon cycling. However, little is known about how these impacts vary with topography in subtropical forests characterized by complex terrain where both AM and EcM trees co-occur. Here, we analyzed 972 soil samples from a 25-ha fully mapped subtropical forest plot to investigate the effects of mycorrhizal type and topography on soil carbon accumulation. Results reveal that the upper slope position harbors a higher abundance of EcM tree species. Both upper slope position and EcM tree dominance (percentage of the total basal area of ECM trees vs. all trees) positively affected aboveground biomass, forest floor thickness, and soil acidification, leading to higher soil carbon concentration and C:N ratio. Slope degree had minimal effect on AM/EcM tree distribution, but could strongly regulate the effects of tree mycorrhizal type on soil carbon concentration. The positive relationship between EcM tree dominance and soil carbon concentration was observed only on gentle slopes, but was negligible on steep slopes. Therefore, soil carbon accumulation in this subtropical forest are shaped by the combined effects of topography and tree mycorrhizal types. Our findings emphasize the importance of topography in regulating AM/EcM tree distribution and their impacts on soil carbon processes. Topographic attributes should be accounted for in future studies on mycorrhizal control over soil carbon and nutrient cycling.

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.

Studying spatial distribution patterns and intraspecific and interspecific associations of tree species is crucial for understanding the maintenance of biodiversity and offering insights into community dynamics and stability. The Shennongjia National Park, located in the transition zone between the (sub)tropics and the temperate climate, holds great significance for understanding how species interact with each other and coexist within forest communities. We used data from a fully mapped 25 ha montane deciduous broad-leaved forest dynamic plot at Shennongjia (SNJ) National Park, central China, to conduct a community-level evaluation of spatial distribution patterns and intraspecific and interspecific associations. We analyzed the spatial distribution patterns of 20 dominant species with univariate and bivariate g(r) functions, as well as intraspecific and interspecific associations across different life-history stages. We assessed the relative contributions of underlying processes in community assembly with three models: complete spatial randomness (CSR), heterogeneous Poisson (HP), and antecedent condition (AC). The results showed that all 20 tree species exhibited aggregated distribution patterns within a 100 m scale. After excluding the influence of environmental heterogeneity, the degree of aggregation decreased, and with the increasing spatial scale from 0 to 100 m, the distribution gradually shifted from aggregated to random or uniform appearance. Positive associations were common in different life-history stages. Negative associations were common across different species, while most of the intraspecific and interspecific associations turned out to be irrelevant when environmental heterogeneity was excluded. We concluded that habitat heterogeneity and dispersal limitation may primarily determine the spatial distribution of species in subtropical montane deciduous broad-leaved forests. This indicates that species distribution may align with environmental patterns, and interspecific correlations may exist. However, the exact responses of these species to environmental changes remain uncertain. Upcoming management approaches ought to concentrate on ongoing observation, which is crucial for mitigating how climate change might affect species distribution and community interactions, thus guaranteeing enduring stability and the conservation of biodiversity.

Berchemiella wilsonii (Schneid.) Nakai is one of the National Key Protected Wild Plants in China, and one of the 120 Plant Species with Extremely Small Populations in China. By combining PacBio HiFi sequencing, DNBSEQ sequencing and Hi-C sequencing, we have assembled a chromosome-scale, haplotype-resolved genome for B. wilsonii. The final assembled haplotype A and haplotype B genomes were 216.84 Mb and 217.69 Mb, anchored to 2n = 24 chromosomes, all chromosomal ends contain telomeric characteristic motifs (TTTAGGG), only haplotype A has one gap, both close to a T2T genome assembly, with contig N50 lengths of 18.24 Mb and 18.03 Mb, respectively. Further, BUSCO analysis showed an extremely high assembly completeness (98.9% complete BUSCO genes). The genome contains a total of 22,828 coding genes, of which 21,992 (96.34%) were functionally annotated. This is the first report of the genome of B. wilsonii and the high-quality genome will provide new insights into evolutionary history and taxonomic classification challenges of endangered plant species.

Understanding the mechanisms of species diversity maintenance is crucial for appreciating community assembly and predicting responses to global climate change. Niche differentiation is one of the most important mechanisms underlying biodiversity maintenance across ecosystems. However, direct evidence for niche differentiation remains scarce in subtropical speciose forests. In this study, a 25-ha (500 m × 500 m) subtropical montane deciduous broadleaved forest dynamics plot in Shennongjia national park was developed to assess species-habitat associations across life history stages. Five habitat types were identified using multivariate regression trees and mapped to 625 20 m × 20 m quadrats. Torus-translation randomization tests identified species-habitat associations across life forms and life stages. Out of 105 species, 81 were significantly associated with at least one habitat type and 65 associated with elevation or convexity (49 species with elevation and 36 with convexity). Across all life stages, saplings were most strongly related to low elevation habitats, while juveniles and mature trees most often correlated with the “low convex slope” habitat type. Canopy and shrub species were positively correlated with the “high convex slope” and “low convex slope” habitat types, respectively. In conclusion, niche differentiation during regeneration (based on topographic heterogeneity) is essential for stable multi-species coexistence and the maintenance of biodiversity in subtropical speciose forests. Future studies are needed to examine how demographic rates shift along environmental gradients of convexity and elevation, providing a more in-depth understanding of niche differentiation in forest ecosystems.

为探究濒危植物小勾儿茶(Berchemiella wilsonii)及变种毛柄小勾儿茶(B.wilsonii var.pubipetiolata)的种群结构及其动态特征，该研究以湖北、安徽、浙江现存有记录的小勾儿茶和毛柄小勾儿茶野生种群为研究对象，基于种群生态学调查绘制种群结构图，建立静态生命表，拟合存活曲线，分析种群生存力，计算种群动态变化指数，并进行时间序列预测分析。结果表明：(1)小勾儿茶种群结构为幼龄个体占比较高的金字塔型，但其幼体在成长过程中损耗较大，成体较少；毛柄小勾儿茶种群幼龄级个体缺乏，中龄级个体较多，成龄个体稀少，呈纺锤型结构。(2)模型检验发现，两个物种的存活曲线均趋近于Deevey-Ⅲ型，表明二者在幼龄级的死亡率较高且在Ⅵ龄级均达到峰值。(3)小勾儿茶种群的生存率和累积死亡率在Ⅱ龄级达到平衡，毛柄小勾儿茶则在Ⅵ龄级达到平衡，表明小勾儿茶更早进入衰退期。(4)种群动态指数显示，二者都属于易受外界干扰的增长型种群，对干扰具有较高的敏感性。(5)时间序列预测显示，在经历2个、4个、6个和8个龄级后，小勾儿茶种群的个体数在每个龄级中均有不同程度的增加，而毛柄小勾儿茶种群幼龄级个体缺乏，中龄级个体减少，成龄级个体增加，种群面临衰退。综上认为，对于二者应采取不同的保护对策，小勾儿茶种群幼苗死亡率高，应进行适当疏林提高光照促进幼苗存活，同时减少人为干扰；毛柄小勾儿茶幼龄级个体严重缺失，应加强人工繁育技术的研究，及时补充幼苗回归保育，避免种群衰退和实现物种多样性资源的保护利用。

Understanding the spatial distribution characteristics and underling mechanisms of taxonomic, phylogenetic and functional diversity is crucial for advancing global biodiversity conservation. Here, we investigated the latitudinal and longitudinal patterns of multifaceted biodiversity of montane forest in a biodiversity hotspot, South-Central China. Multiple linear regression and hierarchical analysis were used to identify the critical factors affecting biodiversity. The results concluded that the latitudinal patterns of taxonomic, phylogenetic, and functional diversity were congruent with the latitudinal diversity gradient from the equator to the poles. Climatic and edaphic factors, particularly precipitation, played a crucial role in spatial patterns of biodiversity. Climatic and edaphic variables simultaneously explained 48%-66% of the spatial variation of multidimensional diversity, except Rao’s phylogenetic quadratic entropy. There were significant associations among multiple measures of diversity in subtropical montane forests. High water availability and low seasonal variation underlie the greater coexistence of tree species at low latitudes. These results present robust evidence for congruent latitudinal patterns of taxonomic, phylogenetic, and functional diversity, and provide a striking explanation that the same filtering effects of precipitation result in positive relationships among multifaceted diversity. Species richness might be a reliable indicator of taxonomic, phylogenetic, and functional diversity, and may be reasonably applied for conservation planning and forest management in subtropical montane regions.

Successful ex situ conservation of plant populations requires a high degree of genetic representativeness. However, spatially biased sampling in ex situ conservation efforts may fail to capture all wild genetic clusters for species with range-wide genetic structure. To investigate the extent of spatially biased sampling in living collections and the coverage of wild genetic clusters in plant populations under ex situ conservation worldwide, we combined a global synthesis of ex situ conservation efforts with a case study of an endangered riparian plant species, Myricaria laxiflora. Our analysis of ex situ conservation worldwide revealed that the majority (82.6%) of ex situ populations fail to cover all wild genetic clusters, largely due to spatially biased sampling with low geographic coverage. Our case study of M. laxiflora showed that genetic diversity differed between the ex situ and upstream populations, while it was comparable between ex situ populations and other wild populations. However, current ex situ populations did not cover all wild genetic clusters, as the upstream genetic cluster was previously uncollected. Our study suggests that the failure to cover all wild genetic clusters in ex situ populations is a widespread issue, and ex situ populations with high genetic diversity can also fail to cover all wild genetic clusters. In future ex situ conservation programs, both the importance of high genetic diversity and the high coverage of wild genetic clusters should be prioritized.

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 regeneration of plants endemic to remote mountain areas is thought to be relatively unimpacted by human disturbances but rather dominated by abiotic factors, such as geography, climate, and soil. However, because human disturbances are accelerating the extinction of montane plants and the loss of montane forest, this balance may be shifting. Yet, the relative effects of abiotic factors and human disturbances to montane plant regeneration are still largely unclear. Here, we investigated the geographic pattern of regeneration (ratio of seedling and ratio of sprout) and assessed the impacts of abiotic and anthropogenic factors for an endangered montane tree species (Davidia involucrata) across its distribution range in China. We found that the ratio of seedling increased from south to north, whereas the ratio of sprout exhibited an opposite pattern, indicating that under climate warming this species may adopt sprout regeneration as a potential strategy to buffer population contraction at the southern edge. Moreover, while climatic factors were the main drivers of regeneration, anthropogenic factors were also important. Of note, the proportion of pasture land area had a significant positive effect on sprouting, with more sprout regeneration at grazed sites and a higher ratio of sprout at sites with a greater intensity of human disturbance. Our findings suggested that, in addition to climate change, human disturbance is also an important driving factor of the regeneration of plants native to remote mountain areas, and we emphasized that researchers and policymakers should take it into account when protecting endangered plants and managing forest biodiversity.

Over-splitting of plant taxa refers to the splitting of plant entities into an excess of small taxonomic units. The over-splitting of intraspecific taxa (e.g., variety) can challenge the legal delimitation of threatened species and the effective allocation of limited conservation resources. The dove tree (Davidia involucrata) has two varieties, namely D. involucrata var. involucrata and D. involucrata var. vilmoriniana, which are distinguished mainly by the appearance of trichomes on the leaf back or not. This traditional classification remains debated because of its minor visible morphological differences and the lack of genetic evidence. We collected range-wide morphological (trichome density and geometric morphometrics), whole-genome resequencing (genome-wide SNPs), and type specimen data to examine taxa boundaries. The leaf trichomes of this species complex are simple (unbranched) non-glandular, and the density varies continuously. Geometric morphometric analysis demonstrated that the leaf shape cannot be unambiguously separated. Within the phylogenetic tree, the two putative taxa were mixed. Population genetic structure analyses consistently revealed three well-supported genetic clusters, whose geographic distribution did not match those of the two putative taxa. Collectively, D. involucrata var. vilmoriniana is not genetically or morphologically differentiated from D. involucrata var. involucrata. The type specimens of the two varieties were collected from distant areas, indicating that their splitting might be caused by collection bias. Our study highlights the importance of integrative taxonomy approaches in unravelling the over-splitting of intraspecific ranks and providing empirical support for the abandonment of over-splitting varieties in wild plant taxonomy.

Seed mineral nutrition is essential for early seedling establishment, and varies under different environmental conditions. However, the intraspecific variation of multi-elements in seeds and the relative effects of climate and soil on seed elements remain unclear, even though understanding these factors is crucial for predicting plant reproductive responses to global changes. Here, we sampled seeds from Euptelea pleiospermum across 18 populations in China. We quantified the inter-population variation of 12 elements in the seeds and analysed their relationship with soil characteristics and climatic variables. We also explored the relationship of N and P concentrations between seeds and leaves. Results showed that seed elements were highly variable across different populations, with macroelements exhibiting lower variability than most of the microelements. Along the latitudinal gradient, the concentrations of K, Ca, Fe and Al in seeds increased, while the concentrations of C and Mn decreased. The stoichiometry of seed elements did not significantly correlate with latitude. Seed element concentrations were associated with both soil and climatic variables, and the influence of soil conditions on intraspecific variations is comparable to or even greater than climatic factors. However, seed stoichiometry was less related to environmental factors. Seeds had higher P but lower N than leaves, with no correlation between seed elements and leaf elements. Our findings suggest that mountain tree species respond to different local environments by adjusting seed element concentrations while maintaining relatively stable seed stoichiometry. We emphasize that, in addition to climate change, soil conditions should be considered when predicting the influence of environmental changes on the elemental composition of plant reproductive organs. (sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(Euptelea pleiospermum)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)18(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)12(sic)(sic)(sic)(sic)(sic)(C,N,P,K,Ca,Mg,Fe,Mn,B,Zn,Cu,Al)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)N,P(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic):(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)K,Ca,Fe(sic)Al(sic)(sic)(sic)(sic), (sic)C(sic)Mn(sic)(sic)(sic)(sic);(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic);(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)P(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)N(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)N,P(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic), (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).

It is well known that evergreen and deciduous species possess different functional traits and utilize different strategies in growth and adaptation to environments. However, little work has been done to elucidate whether leaf habits mediate the effect of trait-environment interactions on plant performance. In this study, our subjective was to illuminate whether relative growth rate of deciduous and evergreen species is influenced by multiple trait-environment interactions. We conducted measurements on eight leaf traits of 1230 individuals belonging to 25 species in a subtropical evergreen and deciduous broad-leaved mixed forest. Additionally, we collected data on topographic factors, edaphic variables and competition index. Subsequently, we employed generalized linear mixed model to analyze plant relative growth rate, considering high-order trait-environment interactions for both evergreen and deciduous species. We also visualized the effects of these interactions on growth patterns. Our results showed that leaf habits were divided by trait PC1 (41.8%) which was related to leaf lifespan and resource acquisition. Evergreen species tended to have greater interspecific variation compared to deciduous species. Notably, the inclusion of trait-environment interactions significantly improved growth predictions for both leaf habits, although explanatory power of deciduous models was always higher than that of evergreen species. Furthermore, we observed variability in the effects of trait-environment interactions on plant performance varied between leaf habits, leading to different optimal models for each leaf habit, even when they shared similar trait-environment context. These results indicated that difference of life history strategies between leaf habits could be reflected by trait-environment interactions. We emphasized the importance of leaf habits in explaining forest productivity and functions, and future research should focus on the effects of leaf habits on other demographic metrics to understand species coexistence in mixed forests.

The updated List of National Key Protected Wild Plants(LNKPWP)was released by National Forestry and Grassland Administration and Ministry of Agriculture and Rural Affairs of China in 2021.By integrating literature search,herbarium record,field investigation and expert consultation,we compiled the updated list,investigated the geographic distribution map,research progress,threatened status,and protection status of national key protected wild plants(NKPWP)in Hubei Province.The results are as follows:(1)There are 155 species on the LNKPWP in Hubei Province,of which 11 species are protected at Category Ⅰ and 144 species are protected at Category Ⅱ.(2)Geographic distribution of NKPWP in Hubei Province is uneven and concentrated in West and Southwest Hubei,with Shennongjia and Lichuan have the greatest numbers of NKPWP.(3)The most studied species are the species with economic value,flagship species and regional representative species.In addition,more than a third of the species(55 species)are almost unstudied.The research of NKPWP in Hubei Province focused on genetic diversity,genetic structure,future distribution prediction under global change conditions,and phylogeography,etc.(4)According to the Red List of China Biodiversity—Volume of Higher Plants,the NKPWP in Hubei Province contain 9 critically endangered species,30 endangered species,41 vulnerable species and 19 near-threatened species.The main threatened factors are direct mining or logging,habitat degradation or loss,and species intrinsic factors.(5)Until now,137(88.4％)species of NKPWP in Hubei Province are wholly or partially located in protected areas,and the remaining 18 species(11.6％)are completely located outside protected areas.A total of 93 species of NKPWP have been introduced and cultivated in Hubei Province,while the other 62 species have not been recorded under ex situ conservation.In addition,very few species have been reintroduced into the wild.(6)Up to now,although the distribution ranges of seven wild plants in Hubei Province(five of which are endemic to Hubei)are limited and they are negatively affected by internal causes and human interference,they have not been included in the LNKPWP.In addition,this study points out the knowledge gaps in the research and protection of NKPWP in Hubei Province,and puts forward specific research suggestions and protection strategies.

1. Ex situ conservation is an effective approach to prevent the extinction of endangered species. Biotic interactions (e.g. herbivory and pollination) are critical to ex situ conservation success, including plant establishment, survival and reproduction. However, shifts in biotic interactions between wild and ex situ populations are still poorly understood. 2. We compared herbivory and pollination characteristics between the only wild population (WP) and three ex situ populations (LP, local population, nearby WP; NP, north population, ca. 850 km; and SP, south population, ca. 750 km) of a critically endangered tree species (Sinojackia huangmeiensis) to explore the latitudinal changes in plant-invertebrate interactions. 3. Larvae of the Limacodidae family were the dominant herbivores in WP, LP and NP, while the only herbivore observed in SP was snail. Compared to WP, the leaf herbivory rate was unchanged in LP but decreased in NP and SP. Leaf defence traits (total phenols, tannins, leaf thickness and leaf dry matter content) increased or remained unchanged in the three ex situ populations. A pollinator (Apis cerana) of S. huangmeiensis was present in the four populations. NP and SP lacked some pollinators that were found in both WP and LP, but they shared one pollinator that was not observed in WP and LP. The pollinator visiting frequency increased in SP, while it did not change significantly in LP and NP. 4. Synthesis and applications. Our results suggested that both herbivory and pollination of Sinojackia huangmeiensis changed in ex situ populations, with complete or partial changes in herbivores, leaf herbivory rate, pollinators, pollinator visiting frequency and fruit set in the two distant ex situ populations. This work provides a unique empirical study of shifts in both antagonistic and mutualistic biotic interactions between wild and ex situ populations. We emphasized that it is essential to integrate herbivore and pollinator management in future ex situ conservation of plant species.