Kuiling Zu

Summary: Ongoing global warming drives species range shifts along latitudinal and elevational gradients, but many terrestrial species cannot keep pace with rapid climate change. The changes in species' elevational range sizes are critical for assessing their response to climate change and extinction risk. The growing digitization of herbarium specimens provides a valuable opportunity to understand species range dynamics. We explore the elevational range size and the upper and lower range changes of plants in 29 mountains of China and compare the determining factor affecting the shifts in elevational range size. The upper range limits of plants shifted downward 15 m, while the lower range limits shifted upward 34 m on average. Plants tended to contract their elevational range size, with species occurring at middle/high elevations showing greater average reductions. Shifts in elevational range size are related to changes in upper and lower range limits. Temperature change and species' thermal adaptations are the primary drivers of these shifts, although the changes in upper and lower range limits are driven by different factors. Large‐scale digitized specimens can improve our understanding of dynamic changes in range size and provide valuable resources to support biodiversity conservation.

Flowering phenology has major impacts on physiological processes, survival, and reproductive success in angiosperms, serving as a critical biological indicator of climate change impacts. However, changes in flowering phenology and their determinants in subtropical montane ecosystems remain poorly quantified at continental extents. Here we investigated the determinants of flowering phenology shifts over the past century across 11 subtropical mountains in China. Based on century‐long herbarium collections of 784 flowering plant species in these mountains, we first used linear regression models to assess the magnitude and direction of changes in flowering time for each species in each mountain separately. Then, we investigated the underlying drivers of changes in flowering time, including climate changes, species traits as well as changes in species elevation range size. Our analyses revealed an average advancement in flowering phenology of 3.8 days per decade, though marked regional disparities emerged: flowering times were advanced in southeastern mountains but delayed in southwestern ones. Climate change, species functional traits, and mountain properties all had significant effects on the observed changes in flowering time. Notably, the flowering time of lowland and non‐native plants was advanced more than that of alpine and native plants. A key finding was the negative correlation between flowering time changes and elevational range expansions, supporting the hypothesis that phenological plasticity facilitates range adjustments under environmental change. These findings demonstrate that flowering phenological responses are context‐dependent, mediated by complex biotic–abiotic interactions. Our study provides the first biogeographical assessment of flowering phenology shifts in subtropical Asian mountains, offering critical insights for predicting ecosystem stability and informing biodiversity conservation strategies under ongoing climate change.

Introduction: How many species there are in the world remains a fundamental scientific question, serving as a critical reference for formulating and implementing effective biodiversity conservation strategies. The accelerating global biodiversity crisis has propelled scientific interest in understanding spatial-temporal patterns of new species discovery, particularly as these findings inform urgent conservation priorities. Digitalization of plant specimens provides important information on the discovery process of new species and clarifies the general situation of the core distributions in China over the last century. However, the new species discovery process of plants has not been the focus of much attention in Asia. The study analyzes digitized herbarium specimen data to investigate new species discoveries, specimen collection gaps, and collection preferences in China over the past century.Methods: First, we collected the herbarium type specimens data. Then we analyzed sampling biases of functional traits (life form, floral colors, fruit colors and types) in specimens collection and summarize distributional patterns in new species discovery. We answered the question of what plant species are more likely to be found and explored the distribution areas of new species discoveries over the last century.Results: Our results reveal that there are more new plant species been found in herbaceous plants (90.8%) than woody (9.2%) plants, and new species with bright flowers and fruits, and the smaller height are easier to be discovered. There is also an observable inter-annual and seasonal variation in the discovery of new species, with peak collections occurring four year periods, and summer (June-August) witnessing the highest number of new species discoveries. The southern regions of China offer easier access to new species, and higher numbers of new species have been identified in the regions with the richness of plant diversity. The number of specimens collected by individuals (58%) surpasses those collected by teams (42%).Discussion: More attention should also be paid to species with different plant functional traits (herbs, species with bright flowers and fruits) and the potential distribution of vacant regions. This study provides scientific reference and direction for the accelerating discovery of more new species in the future, and also contribute to the future conservation of biodiversity.

Objective Plant functional traits can effectively characterize plant adaptation to environmental changes，and flower color is one of the important functional traits of plant sexual reproduction.Exploring the spatial and temporal distribution pattern and influencing factors in flower color of flowering plants in Gongga Mountain is of of significant scientific value for understanding the evolutionary mechanisms of floral traits in alpine ecosystems and providing theoretical support for biodiversity conservation in mountainous regions. Method The flower color of flowering plants in Gongga Mountain were investigated along 9 altitude gradients from May，July and September of 2018 and 2019，the characteristics such as flower color and flowering date were recorded.The vegetation characteristics of different altitude gradients，climate factors and human activity interference were combined with geospatial analysis techniques and regression models to explore the spatio-temporal variation of the species proportion of different flower colors in Gongga Mountain and its relationship with environmental factors. Result （1）White flowers account for the highest proportion of plant species in Gongga Mountain，up to 27%，followed by yellow and purple flowers，accounting for 22% and 17%，respectively.There are significant differences in the proportion of flower color types among different life forms of plant species.In both trees and shrubs，white flowers account for 54% and 30%，respectively；in herbs，yellow flowers account for 25%，and in vines，red and purple flowers account for 25%.（2）Along the altitude gradient，the proportions of flower color species along the altitudinal gradient exhibit regular patterns.The flower colors of plant species at low altitude are mainly red，those at middle altitude were mainly red and white，and those at high altitude were mostly purple，yellow and blue.（3）The composition of plant species with different flower colors varies across survey months.July exhibits the highest flower color diversity，with white-flowered species accounting for the largest proportion in May，July，and September，followed by yellow-flowered species.（4）The proportion of blue，yellow and purple flower species along the altitude gradient is significantly correlated with climatic factors and human influence index，suggesting that the flower color pattern of Gongga Mountain is jointly regulated by climatic conditions and human interference. Conclusion The flower colors of plant species in Gongga Mountain exhibit significant spatial variation patterns along altitudinal gradients and monthly dynamic patterns.The formation of temporal and spatial pattern of flower color of flowering plants is not only regulated by climatic factors such as temperature，precipitation and evapotranspiration，but also related to the interference of human activities.Further research on the evolutionary ecology of flower color is needed to provide more first-hand information for understanding and protecting plant diversity.

Mountains have been recognized as biodiversity hotspots and possess strong elevational gradients. Whether these gradients exhibit similar characteristics in the multidimensional diversity patterns across different mountain ranges is a subject of inquiry. Exploring the elevational patterns of the diversity and phylogenetic information of plant species in the different subtropical mountains is necessary. Here, we compiled the elevational patterns of plant diversity occurring in the eight subtropical mountains of China and focused on the assessment of the patterns and determinants of the multi‐dimensional diversity and phylogenetic structure in different mountains. We also detected the elevational patterns and their relationship between different groups. The results indicate two main patterns of multi‐dimensional diversity: monotonic decrease and hump‐shaped, along with the area effect on the species diversity. There is a strong positive link between the non‐native and native species of species richness, and significant differences in phylogenetic structure's elevational distribution. We did not find the same rule in the mountains that the plant species in the lowlands indicate phylogenetic overdispersion, and the species in the higher elevation regions indicate phylogenetic clustering. We found that the plants' diversity peak is related to the mountains size, and this result showed that we should pay more attention to the conservation of plant communities in the higher elevation regions for the higher mountains. This study suggested that we should take different protective measures for the subtropical mountains: the lowland regions should be paid more attention in Mt. Lushan (LS), Mt. Guanshan (GS), Mt. Huanggang (HG), and Mt. Fanjing (FJ), and the middle‐altitude regions should be of concern for other mountains. This study helps to better understand the elevational gradients of species diversity on different scales and provides supporting scientific basis for biodiversity conservation in the subtropical mountain regions.

Flowering phenology of plants, which is important for reproductive growth, has been shown to be influenced by climate change. Understanding how flowering phenology responds to climate change and exploring the variation of this response across plant groups can help predict structural and functional changes in plant communities in response to ongoing climate change. Here, we used long-term collections of 33 flowering plant species from the Gongga Mountains (Mt. Gongga hereafter), a biodiversity hotspot, to investigate how plant flowering phenology changed over the past 70 years in response to climate change. We found that mean flowering times in Mt. Gongga were delayed in all vegetation types and elevations over the last 70 years. Furthermore, flowering time was delayed more in lowlands than at high elevations. Interestingly, we observed that spring-flowering plants show earlier flowering times whereas summer/autumn plants show delayed flowering times. Non-synchronous flowering phenology across species was mainly driven by changes in temperature and precipitation. We also found that the flowering phenology of 78.8% plant species was delayed in response to warming temperatures. Our findings also indicate that the magnitude and direction of variation in plant flowering times vary significantly among species along elevation gradients. Shifts in flowering time might cause trophic mismatches with co-occurring and related species, affecting both forest ecosystem structure and function.

Aim: Significant changes in species elevational ranges in mountains have been repeatedly documented, yet the direction, magnitude and drivers of these shifts remain controversial. Presently, there is still lacking evidence about the general nature of species elevational range shifts in eastern Eurasia in response to anthropogenic climate change. By using historical specimen records and recent field observations for 735 seed plant species across 29 China's mountains, we assessed changes in species' elevational centroids and their drivers.Location: China.Time Period: 1950–2018.Major Taxa Studied: Seed plant species.Methods: The elevation records of all sampled occurrences in each mountain during the two time periods were estimated, and the null models were developed to test the sampling bias. Ecological niche models (ENMs) were used to evaluate the relative importance of climate factors in constraining each species distribution. Generalized linear models (GLMs) to test the relationships between the centroid elevational range shifts of species and different divers.Results: We found that 54% of the species shifting upward and 46% downhill. However, species' elevational shifts significantly differed among species and mountains. Herbaceous and lowland species moved upward faster than woody and high‐elevation species. Species in temperate mountains and in mountains with taller elevational gradients moved upward, while species in subtropical mountains and in mountains with shorter elevational gradients moved downward. Precipitation changes experienced by species, species' climatic adaptations, several species' functional traits and mountain size all contributed to explain the magnitude of species' centroid elevational range shifts.Main Conclusions: Our results highlight complex biodiversity redistribution of seed plants across Chinese mountains, not necessarily conforming to the trend of species upward shifts in elevation. Changes in precipitation regimes may blur the simplistic assumption of isotherm tracking. This study fills an important geographic shortfall for our understanding of biodiversity redistribution under anthropogenic climate change.