Understanding ecosystem carbon sequestration change and its environmental drivers is fundamental for revealing regional carbon sink patterns and ecosystem response processes, yet differences in carbon sequestration dynamics between ethnic autonomous and non-autonomous areas in western China remain insufficiently explored. Here, these two regional types were regarded as socio-ecological units with distinct environmental backgrounds, ecosystem compositions, land-use structures, and governance contexts. Using total carbon sink (TCS), net primary productivity (NPP), and multi-source data from 2001 to 2025, we combined trend analysis, ridge regression, and interpretable machine learning to investigate differences in carbon sequestration change, climate sensitivity, and driving mechanisms between the two regional types. The results showed that ecosystem carbon sequestration in western China increased significantly during 2001–2025, with TCS rising from 1.40 to 1.60 PgC·yr-1 and NPP increasing from 440 to 500 gC·m-2·yr-1. Ethnic autonomous areas constituted the dominant component of the regional carbon sink, with TCS increasing from 1.14 to 1.27 PgC·yr-1 and NPP increasing from 420 to 480 gC·m-2·yr-1, contributing 78.55% of the total NPP and 106.29% to interannual variability. In contrast, non-autonomous areas had lower total carbon sink values but higher mean NPP and steeper growth rates, with TCS increasing from 0.25 to 0.33 PgC·yr-1 and NPP increasing from 550 to 650 gC·m-2·yr-1. NPP in ethnic autonomous areas was more sensitive to precipitation and soil moisture, indicating stronger water limitation, whereas non-autonomous areas showed a more pronounced increase in temperature sensitivity and greater weakening in sensitivity to VPD and radiation. Analysis of driving mechanisms further revealed a climate-dominated pattern in ethnic autonomous areas and a more pronounced pattern of joint soil–climate control in non-autonomous areas. These differences reflect combined effects of administrative characteristics, environmental gradients, ecosystem composition, and land-use intensity, rather than administrative status alone.

Traits and their correlation networks can reflect plant adaptive strategies. However, variations in traits and trait correlation networks across heteromorphic leaves within species remain largely unexplored. In this study, we systematically quantified a diverse array of leaf traits—spanning morphology, anatomy, physiology and biochemistry—among the striped, lanceolate, ovate, and broadly ovate leaves of Populus euphratica, aiming to elucidate the adaptive differences across these various leaf types. We found that the four heteromorphic leaves showed significant differences in leaf traits. From striped leaves to broadly ovate leaves, leaf size, leaf thickness, water use efficiency and catalase content significantly increased, while specific leaf area showed the opposite pattern. Principal component analysis and cluster analysis revealed distinct aggregation and clear demarcation of the four leaf types, indicating substantial variations in trait compositions and their distinct ecological adaptations. Plant trait networks varied significantly across the four leaf types, with the broadly ovate leaves exhibiting a fragmented network structure that enhances their modularity. This suggests strong resilience to disturbances and is consistent with the characteristic foliage on mature trees. Regardless of leaf type, nitrogen and phosphorus consistently emerged as hub traits within plant trait networks, underscoring their fundamental role in driving physiological processes and influencing phenotypic expression. This study meticulously delineates the variations in both individual leaf traits and trait correlation networks across the heteromorphic leaves of P. euphratica, significantly deepening our understanding of plant adaptive strategies.

To investigate the adaptive characteristics of Ammopiptanthus mongolicus,a rare and endangered species native to the desert regions of Northwest China,under the context of climate change,we conducted a comprehensive analysis of the functional traits of natural A.mongolicus populations in gravelly habitats across Inner Mongolia,Ningxia Hui Autonomous Region,and Gansu Province.Based on self-calibrating Palmer Drought Severity Index(scPDSI),using regression analysis and one-way ANOVA,we assessed the drought conditions of the study sites and explored the functional traits of A.mongolicus and their adaptive responses to environmental factors.The study employed other methods,including GPS-based measurements of geographic coordinates and altitude,along with assessments of soil moisture,leaf structural traits,physiological and ecological indicators,and growth parameters.The results were as follows:(1)The intraspecific coefficient of variation in A.mongolicus ranged from 7.06％to 39.54％,with considerable variability observed in leaf morphology and structural composition.(2)As the study regions became increasingly humid,significant decreases were observed in leaf dry matter content,leaf thickness,petiole length,petiole dry weight,petiole fresh weight,and transpiration rate(P＜0.05),while significant increases were found in leaf fresh weight,leaf length,leaf shape index,and water use efficiency(P＜0.05).(3)The leaf functional traits of A.mongolicus were significantly influenced by environmental conditions,with key factors including soil sand content,average annual wind speed,soil clay content,and average annual potential evapotranspiration.(4)The plant trait networks(PTNs)of A.mongolicus exhibited a loosely structured yet locally clustered configuration in sandy habitats,while in gravelly habitats,traits were more coordinated.These findings suggest that the development of leaf traits in A.mongolicus is a complex process shaped by the interaction of multiple environmental factors.A.mongolicus adapts to different habitats by modulating trait modules,either coordinating traits as a whole or differentiating them into distinct modules to mitigate water stress in arid environments.In summary,A.mongolicus demonstrates distinct functional traits and adaptive strategies under varying environmental conditions,with these traits significantly influenced by environmental factors.This study provides scientific basis for the mechanisms of environmental adaptation in A.mongolicus and serves as a reference for formulating conservation and restoration strategies for this endangered species.

Endogenous metabolites play key functions in many important physiological and biochemical processes. The comprehensive in situ detection and direct imaging of metabolites in bio-tissues by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is very important for understanding complex and diverse biological processes and has become an essential aspect of spatial omics. In this work, 4-aminoazobenzene (AAB) was successfully screened and optimized as a new negative ion (-)MALDI matrix to enhance the in situ detection and imaging of metabolites in tissues using MALDI-MSI. Obviously, AAB exhibited superior properties in terms of ultraviolet absorption, background ion interference, matrix morphology, and metabolite ionization efficiency. AAB was used for in situ detection and imaging of metabolites in rat brain and germinating Chinese yew seed tissue sections, where 264 and 339 metabolite ion signals were successfully detected and imaged using (-)MALDI-MS, respectively. In addition, high-resolution imaging of mouse eyeball section using MALDI-timsTOF MSI with spatial resolution of up to 10 μm was successfully carried out, showing that AAB is an efficient (-)MALDI matrix for capturing high-resolution images of metabolites in biological tissue sections.

Jojoba (Simmondsia chinensis Schneider), the sole species in the Simmondsiaceae family, holds significant economic value. Understanding the mechanism of seed germination and post-germination is essential for jojoba breeding programs. For the first time, this study employed matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to comprehensively detect and image endogenous lipids in jojoba seeds during germination and post-germination. Meanwhile, a new method of lithium salt-doped 2-mercaptobenzothiazole (2-MBT) matrix was adopted to detect the wax ester in jojoba seeds. The spatial lipidomic analysis of MALDI-MS revealed the dynamics of lipid alterations during three stages of jojoba seed (stage I, quiescent seed; stage II, germination; stage III, post-germination). MALDI-MSI results demonstrated heterogeneous distributions of differential lipids and main wax esters (WEs) in unique tissue regions of the jojoba seed at different stages. For instance, at stages II and III, three phosphatidylcholines (PCs) (PC(36:2), PC(36:4), and PC(35:3)) are mainly localized in the cotyledons, while the other two PCs (PC(34:1) and PC(36:1)) were distributed in both cotyledons and embryonic axis. In contrast, three phosphatidylethanolamines (PE(36:1), PE(42:4), and PE(42:9)) are primarily distributed near the embryonic axis and phosphatidylserine (PS(32:0)) was found exclusively in the embryonic axis area at three stages. In addition, three phosphatidic acids (PA(40:7), PA(46:2), and PA(42:1)) displayed highly accumulated in the middle of the cotyledons at stages II and III. Besides, WEs are continuously degraded mainly in the cotyledons during germination and post-germination processes. This study offers new insights into lipid alterations from a spatial lipidomics perspective and can contribute to our understanding of the role of these specific lipids during jojoba seed germination and post-germination. These findings will deepen our understanding of the metabolic processes involved in jojoba seed germination and seedling development and have underlying implications for crop improvement and seed quality control.

1. Hydraulic traits are major determinants of plant fitness, thus exerting control over vegetation structure, function and distribution. Yet it remains unclear whether and how hydraulic traits respond to environmental stimuli (i.e. phenotypic variation of hydraulic traits; PVHT) and if the coordination between different hydraulic traits and the trait-climate relationship are affected by PVHT. 2. Here, we synthesized data of PVHT (maximum hydraulic conductivity and water potential inducing 50% loss of hydraulic conductivity) and potentially related morphological and anatomical traits (e.g. sapwood density, branch Huber value, mean and hydraulic weighted conduit diameter). We analysed the magnitude, direction and source of variation of the plastic response, as well as the influence of environmental factors on trait coordination. Additionally, we compared the intra- and inter-specific variation between key hydraulic traits and climate metrics (mean annual precipitation and mean annual temperature) at the site of growth, as well as across the population range. 3. PVHT was highly variable in both magnitude and direction, which was contingent on the environmental factor. The variation in PVHT mainly occurred at high taxonomic levels (i.e. family and genus), whereas phenology explained little variation for PVHT. Despite the high variability, trait correlation remained robust in the presence of environmental stimuli. Moreover, trait-climate relationships differed at inter-specific and intra-specific levels. The intra-specific variation of hydraulic traits in most species showed no correlation with climate metrics compared with the high correlation of hydraulic traits with climate metrics across species. 4. Our findings suggest that the high variability of PVHT does not affect the trait correlation which may be valuable in predicting vegetation dynamics under varying environments. The distinct trait-climate relationships highlight the need to unravel the driving force of PVHT, as well as the adaptive strategy across populations. Read the free Plain Language Summary for this article on the Journal blog.

Hydraulic traits dictate plant response to drought, thus enabling better understanding of community dynamics under global climate change. Despite being intensively documented in woody species, herbaceous species (graminoids and forbs) are largely understudied, hence the distribution and correlation of hydraulic traits in herbaceous species remains unclear. Here, we collected key hydraulic traits for 436 herbaceous species from published literature, including leaf hydraulic conductivity (Kleaf), water potential inducing 50 % loss of hydraulic conductivity (P50), stomatal closure (Pclose) and turgor loss (Ptlp). Trait variation of herbs was analyzed and contrasted with angiosperm woody species within the existing global hydraulic traits database, as well as between different growth forms within herbs. Furthermore, hydraulic traits coordination was also assessed for herbaceous species. We found that herbs showed overall more negative Pclose but less negative Ptlp compared with angiosperm woody species, while P50 did not differ between functional types, regardless of the organ (leaf and stem). In addition, correlations were found between Kleaf and P50 of leaf (P50leaf), as well as between Pclose, P50leaf and Kleaf. Within herbs, graminoids generally exhibited more negative P50 and Ptlp, but lower Kleaf, relative to forbs. Within herbs, no clear pattern regarding hydraulic traits-climate relationship was found. Our analysis provided insights into herb hydraulic, and highlighted the knowledge gaps need to be filled regarding the response of herbs to drought.

Plant samples with irregular morphology are challenging for longitudinal tissue sectioning. This has restricted the ability to gain insight into some plants using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Herein, we develop a novel technique termed electromagnetic field-assisted frozen tissue planarization (EMFAFTP). This technique involves using a pair of adjustable electromagnets on both sides of a plant tissue. Under an optimized electromagnetic field strength, nondestructive planarization and regularization of the frozen tissue is induced, allowing the longitudinal tissue sectioning that favors subsequent molecular profiling by MALDI-MSI. As a proof of concept, flowers, leaves and roots with irregular morphology from six plant species are chosen to evaluate the performance of EMFAFTP for MALDI-MSI of secondary metabolites, amino acids, lipids, and proteins among others in the plant samples. The significantly enhanced MALDI-MSI capabilities of these endogenous molecules demonstrate the robustness of EMFAFTP and suggest it has the potential to become a standard technique for advancing MALDI-MSI into a new era of plant spatial omics.

Low-molecular-weight (LMW) compounds are ubiquitous in living organisms and play essential roles in biological processes. The direct analysis of LMW compounds in biological tissues by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) could provide a more comprehensive understanding of their essential functions. Here, we evaluated 4-Nitrocatechol (4-NC) as a novel positive-ion matrix for enhancing in situ detection and imaging of LMW compounds from the rat liver, brain, and germinating Chinese-yew seed by MALDI-MS. Our results showed that the 4-NC possessed remarkable features, including strong ultraviolet absorption, uniform matrix crystal, excellent chemical stability, and fewer matrix-related background peaks. The use of 4-NC led to the successful detection of 232, 218, and 193 LMW compounds from the three abovementioned tissue sections, respectively. Also, the use of 4-NC improved the imaging quality of LMW compounds in tissue sections through MALDI-MSI and has the potential as a matrix for MALDI tissue imaging of LMW compounds.

Summary A novel metabolomics analysis technique, termed matrix‐assisted laser desorption/ionization mass spectrometry imaging‐based plant tissue microarray (MALDI‐MSI‐PTMA), was successfully developed for high‐throughput metabolite detection and imaging from plant tissues. This technique completely overcomes the disadvantage that metabolites cannot be accessible on an intact plant tissue due to the limitations of the special structures of plant cells (e.g. epicuticular wax, cuticle and cell wall) through homogenization of plant tissues, preparation of PTMA moulds and matrix spraying of PTMA sections. Our study shows several properties of MALDI‐MSI‐PTMA, including no need of sample separation and enrichment, high‐throughput metabolite detection and imaging (>1000 samples per day), high‐stability mass spectrometry data acquisition and imaging reconstruction and high reproducibility of data. This novel technique was successfully used to quickly evaluate the effects of two plant growth regulator treatments ( i.e. 6‐benzylaminopurine and N‐phenyl‐N′‐1,2,3‐thiadiazol‐5‐ylurea) on endogenous metabolite expression in plant tissue culture specimens of Dracocephalum rupestre Hance ( D. rupestre ). Intra‐day and inter‐day evaluations indicated that the metabolite data detected on PTMA sections had good reproducibility and stability. A total of 312 metabolite ion signals in leaves tissues of D. rupestre were detected, of which 228 metabolite ion signals were identified, they were composed of 122 primary metabolites, 90 secondary metabolites and 16 identified metabolites of unknown classification. The results demonstrated the advantages of MALDI‐MSI‐PTMA technique for enhancing the overall detection ability of metabolites in plant tissues, indicating that MALDI‐MSI‐PTMA has the potential to become a powerful routine practice for high‐throughput metabolite study in plant science.

The transition from deep dormancy to seed germination is essential for the life cycle of plants, but how this process occurs in the gymnosperm Chinese yew (Taxus chinensis var mairei), the natural source of the anticancer drug paclitaxel, remains unclear. Herein, we analyse the transcriptome, proteome, spatial metabolome, and spatial lipidome of the Chinese yew and present the multi-omics profiles of dormant and germinating seeds. Our results show that abscisic acid and gibberellic acid 12 homoeostasis is closely associated with gene transcription and protein translation, and the balance between these phytohormones thereby determines if seeds remain dormant or germinate. We find that an energy supply of carbohydrates from glycolysis and the TCA cycle feed into the pentose phosphate pathway during seed germination, and energy supplied from lipids are mainly derived from the lipolysis of triacylglycerols. Using mass spectrometry imaging, we demonstrate that the spatial distribution of plant hormones and phospholipids has a remarkable influence on embryo development. We also provide an atlas of the spatial distribution of paclitaxel C in Chinese yew seeds for the first time. The data from this study enable exploration of the germination mechanism of Chinese yew seeds across several omics levels.

Beihai Wetland is an important habitat stopping place on the Central Asia-India and East Asia-Australia routes of global migratory birds, and is one of the first announced 33 national key wetlands of China. Bird species inventory of Beihai Wetland is sorted out by using the method of sample line and sample point, combined with the field investigation records of bird watching websites and Beihai Wetland Management Institute. The results show that, in total, 188 bird species were recorded in Beihai Wetland. These birds belong to 17 orders, 54 families and 125 genera. Most species（110 species） belong to Passeriformes（accounting for 58.51% of the total）. There are 47 waterbirds, accounting for 25% of the total bird species. 31 bird species are in the List of State Key Protected Wild Animal Species. The value of G-F index of bird biodiversity in Beihai Wetland is 0.825, indicating that the species richness is at a high level. The results of AFR show that species similarity in the adjacent habitats is high and the distribution of bird species presents a certain natural transition phenomenon. The bird species richness in Beihai Wetland is high and the resources of rare and endangered bird species are rich, owing to the superior geographical location, diverse habitat types, high spatial heterogeneity and rich bird food sources, which is in line with the patch-corridor-matrix model in landscape ecology. Rich bird biodiversity also promotes the functional health and stability of Beihai Wetland ecosystem. Bird biodiversity and habitats in Beihai Wetland are playing a coupling relationship of mutual maintenance. The present study verified the significance of small wetland to bird biodiversity protection. It can provide important reference for the planning, management and development of wetlands.

Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is a powerful approach that has been widely used for in situ detection of various endogenous compounds in tissues. However, there are still challenges with in situ analysis of proteins using MALDI-MSI due to the ion suppression effects of small molecules in tissue sections. Therefore, tissue-washing steps are crucial for protein MALDI tissue imaging to remove these interfering molecules. Here, we successfully developed a new method named the concentration-descending washing strategy (CDWS) with methanol (MeOH), i.e., washing of biological tissue with 100%, 95%, and 70% MeOH solutions, for the enhancement of endogenous in situ protein detection and imaging in tissues using MALDI-MS. The method of MeOH-based CDWS (MeOH-CDWS) led to the successful in situ detection of 272 ± 3, 185 ± 4, and 134 ± 2 protein ion signals from rat liver, rat brain, and germinating Chinese-yew seed tissue sections, respectively. By comparison, 161 ± 2, 121 ± 1, and 114 ± 2 protein ions were detected by three commonly used methods, i.e., Carnoy's wash, ethanol (EtOH)-based CAWS (i.e., concentration-ascending washing strategy, 70% EtOH followed by 90% EtOH/9% AcOH), and isopropanol (iPrOH)-based CAWS (70% iPrOH followed by 95% iPrOH), respectively, in rat liver tissue sections, indicating that 68.9 ± 3.1%, 124.8 ± 3.3%, and 138.6 ± 4.4% more protein ion signals could be detected by the use of MeOH-CDWS than the three abovementioned washing strategies. Our results show that the use of MeOH-CDWS improves the performance of MALDI-MSI for in situ protein detection such as the number and intensity of proteins. The use of MeOH-CDWS improves the fixation of proteins and thus reduces the loss of proteins, which significantly reduces protein delocalization in tissue and enhances the performance of MALDI tissue imaging of protein. Thus, the use of MeOH-CDWS improves the quality of protein images in tissue sections through MALDI-MSI and has the potential to be used as standard practice for MALDI tissue imaging of proteins.

In this study, polyacrylamide gel (PAAG) was successfully used as a new embedding medium to provide the more effective maintenance of biological tissues during the sectioning process, enhancing the tissue imaging of metabolites via matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Herein, PAAG, agarose, gelatin, optimal cutting temperature compound (OCT), and ice media were used to embed rat liver and Atlantic salmon (Salmo salar) eyeball samples. These embedded tissues were then sectioned into thin slices and thaw-mounted on conductive microscope glass slides for MALDI-MSI detection to evaluate the embedding effects. The results showed that PAAG embedding has characteristics superior to those of commonly-used embedding media (e.g., agarose, gelatin, OCT, and ice) with the advantages of one-step operation without heating, a better performance of morphology maintenance, the absence of PAAG polymer-ion-related interference below m/z 2000, and the more efficient in situ ionization of metabolites, providing a significant enhancement of both the numbers and intensities of the metabolite ion signals. Our study demonstrates the potential of PAAG embedding as a standard practice for metabolite MALDI tissue imaging, which will lead to an expanded application scope of MALDI-MSI.

Drought-related tree mortality has become a major concern worldwide due to its pronounced negative impacts on the functioning and sustainability of forest ecosystems. However, our ability to identify the species that are most vulnerable to drought, and to pinpoint the spatial and temporal patterns of mortality events, is still limited. Model is useful tools to capture the dynamics of vegetation at spatiotemporal scales, yet contemporary land surface models (LSMs) are often incapable of predicting the response of vegetation to environmental perturbations with sufficient accuracy, especially under stressful conditions such as drought. Significant progress has been made regarding the physiological mechanisms underpinning plant drought response in the past decade, and plant hydraulic dysfunction has emerged as a key determinant for tree death due to water shortage. The identification of pivotal physiological events and relevant plant traits may facilitate forecasting tree mortality through a mechanistic approach, with improved precision. In this review, we (1) summarize current understanding of physiological mechanisms leading to tree death, (2) describe the functionality of key hydraulic traits that are involved in the process of hydraulic dysfunction, and (3) outline their roles in improving the representation of hydraulic function in LSMs. We urge potential future research on detailed hydraulic processes under drought, pinpointing corresponding functional traits, as well as understanding traits variation across and within species, for a better representation of drought-induced tree mortality in models.

本文通过测定砾质生境中三种不同生长阶段的蒙古沙冬青(Ammopiptanthus mongolicus)(大、中、小)的光合参数,探讨其光合作用变化特征,阐明蒙古沙冬青光合生理生态适应性.研究结果表明:(1)大、中、小蒙古沙冬青的光合作用日变化的净光合速率、气孔导度、胞间二氧化碳浓度、气孔限制值、蒸腾速率、水分利用效率之间存在异同:其中三者净光合速率、气孔导度、气孔限制值均呈"双峰"曲线;净光合速率与蒸腾速率的日均值为中>大>小,因此,中蒙古沙冬青表现出较强的生态适应性.(2)植物光合作用受多种生态因子影响,大、中、小蒙古沙冬青净光合速率与胞间二氧化碳浓度呈显著负相关,与气孔导度、蒸腾速率呈极显著正相关,与气孔限制值呈显著正相关.大蒙古沙冬青光合作用对大气湿度响应更敏感,而中和小型植株光合作用对光照响应更敏感.(3)蒙古沙冬青午间净光合速率的降低原因不同,小蒙古沙冬青为气孔限制,中蒙古沙冬青为非气孔限制,大蒙古沙冬青既有气孔限制又有非气孔限制.(4)中蒙古沙冬青在干旱砾质生境中采用高光合、高蒸腾的生态适应策略,而小蒙古沙冬青则采取低光合、低蒸腾的生态适应策略.该研究有助于理解荒漠植物在砾质生境下的光合生理生态适应性,为荒漠植物保护提供理论依据.

Recently, mass spectrometry imaging (MSI) has drawn more and more attention due to its continuous development and improvement as well as its vital role in the study of biological science. Many MSI-based strategies have been widely applied to the in situ qualitative and quantitative detection and the imaging of endogenous/exogenous molecules in tissues. Among them, matrix assisted laser desorption/ionization MSI (MALDI-MSI) and desorption electrospray ionization MSI (DESI-MSI) are generally regarded as the most commonly used two molecular imaging techniques. MSI, as a histology-based emerging molecular imaging technique, has significant advantages over other imaging techniques because it is a label-free technique which provides high sensitivity, high throughput, and molecular specificity derived from the use of mass spectrometers as detectors for a wide variety of ionized biomolecules in situ within a tissue section. But it still has obvious shortcomings in the in situ analysis of low-polarity and neutral biomolecules. The application of chemical derivatization technology in MSI is one of the most important approaches to overcome these deficiencies of MS molecular imaging. This review provides an overview of various chemical derivatization techniques used in MS analysis, such as esterification derivatization, acylation derivatization, addition reaction derivatization, substitution derivatization, oxidative derivatization, and other derivatizations, and highlights the application of these chemical derivatization methods in the in situ detection and imaging of biomolecules in tissues by MALDI-MSI and DESI-MSI. It can be predicted that with the advance progress of chemical derivatization technology, the application scope of MSI will be further expanded in the fields of spatial metabolomics, spatial lipidomics, spatial proteomics, and spatial glycomics.

In arid and semi-arid regions worldwide, grassland plant species richness is highly sensitive to climate change. Studies assessing local grassland richness patterns have yielded inconsistent trends toward climate change, partly due to differences in recording approaches, environmental conditions, and local flora. Remote sensing presents a valuable opportunity to investigate plant richness–climate change relationships in grasslands across large environmental gradients. Based on spectral diversity indices extracted from Landsat satellite imagery, we explore how plant diversity responds to climate change and aim to determine the major climatic drivers of plant diversity patterns in ten grassland nature reserves worldwide. Plot‐level plant richness was correlated with 19 bioclimatic variables through stepwise linear regression for each climate change scenario in every nature reserve. The performance of the models was assessed according to the model accuracy. We used the fitted models between climatic variables and plant richness from 1990 to 2000 to predict plant richness in 2050 and 2070 under 33 climatic change scenarios for 1120 plots in each reserve. A general tendency toward a decrease in the plot-level plant richness and beta (β)-diversity in the future decades were observed in most cases, although there also were some opposite trends in plant richness. The dominant bioclimatic predictors involved in predictive models varied across sites. Spectral plant richness responses diverge geographically, while β-diversity generally declines under climate change scenarios. Over the next decades, the expected homogeneities in plant species across grasslands encountered on different continents will likely lead to the dominance of climate generalist species. Policy-makers and conservationists therefore need to urgently develop strategies to ensure plant survival, particularly that of locally endemic species under predicted climatic scenarios; human assistance may be required when adjusting their distribution ranges.

The survival and performance of urban forests are increasingly challenged by urban drought, consequently compromising the sustainability and functionality of urban vegetation. Plant-water relations largely determine species drought tolerance, yet little is known about the hydraulics of urban forest species. Here, we report the leaf hydraulic and carbon traits that govern plant growth and drought resistance, including vulnerability to embolism, hydraulic conductivity and leaf gas exchange characteristics, as well as morphological traits that are potentially linked with these physiological attributes, with the aim of guiding species selection and management in urban forests. Plant materials were collected from mature shrubs and trees on our university campus in Beijing, representing 10 woody species common to urban forests in north China. We found that the leaf embolism resistance, represented by the water potential inducing 50% loss of hydraulic conductivity (P50), as well as the hydraulic safety margin (HSM) defined by P50 and the water potential threshold at the inception of embolism (P12), varied remarkably across species, but was unrelated to growth form. Likewise, stem and leaf-specific hydraulic conductivity (Kstem and kl) was also highly species-specific. Leaf P50 was positively correlated with hydraulic conductivity. However, neither P50 nor hydraulic conductivity was correlated with leaf gas exchange traits, including maximum photosynthetic rate (Amax) and stomatal conductance (gs). Plant morphological and physiological traits were not related, except for specific leaf area, which showed a negative relationship with HSM. Traits influencing plant-water transport were primarily correlated with the mean annual precipitation of species climatic niche. Overall, current common woody species in urban forest environments differed widely in their drought resistance and did not have the capacity to modify these characteristics in response to a changing climate. Species morphology provides limited information regarding physiological drought resistance. Thus, screening urban forest species based on plant physiology is essential to sustain the ecological services of urban forests.