The timing of flowering is an important driver of species distribution and community assembly patterns.However,we still have much to learn about the factors that shape flowering diversity(i.e.,number of species flowering per period)in plant communities.One potential explanation of flowering diversity is the mid-domain effect,which states that geometric constraints on species ranges within a bounded domain(space or time)will yield a mid-domain peak in diversity regardless of ecological factors.Here,we determine whether the mid-domain effect explains peak flowering time(i.e.,when most species of communities are flowering)across China.We used phenological data of 16,267 herbaceous and woody species from the provincial Flora in China and species distribution data from the Chinese Vascular Plant Distribution Database to determine relationships between the observed number of species flowering and the number of species flowering as predicted by the mid-domain effect model,as well as between three climatic variables(mean minimum monthly temperature,mean monthly precipitation,and mean monthly sunshine duration).We found that the mid-domain effect explained a significant proportion of the temporal variation in flowering diversity across all species in China.Further,the mid-domain effect explained a greater proportion of variance in flowering diversity at higher latitudes than at lower lati-tudes.The patterns of flowering diversity for both herbaceous and woody species were related to both the mid-domain effect and environmental variables.Our findings indicate that including geometric constraints in conjunction with abiotic and biotic predictors will improve predictions of flowering di-versity patterns.

Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across South-east Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the region.However,phylogenetic relationships of Cymbidium have not been well resolved,hampering in-vestigations of species diversification and the biogeographical history of this genus.In this study,we construct a plastome phylogeny of 56 Cymbidium species,with four well-resolved major clades,which provides a framework for biogeographical and diversification rate analyses.Molecular dating and biogeographical analyses show that Cymbidium likely originated in the region spanning northern Indo-Burma to the eastern Himalayas during the early Miocene(～21.10 Ma).It then rapidly diversified into four major clades in East Asia within approximately a million years during the middle Miocene.Cymbidium spp.migration to the adjacent regions(Borneo,Philippines,and Sulawesi)primarily occurred during the Pliocene-Pleistocene period.Our analyses indicate that the net diversification rate of Cymbidium has decreased since its origin,and is positively associated with changes in temperature and monsoon in-tensity.Favorable hydrothermal conditions brought by monsoon intensification in the early Miocene possibly contributed to the initial rapid diversification,after which the net diversification rate was reduced with the cooling climate after the middle Miocene.The transition from epiphytic to terrestrial habits may have enabled adaptation to cooler environments and colonization of northern niches,yet without a significant effect on diversification rates.This study provides new insights into how monsoon activity and temperature changes affected the diversification dynamics of plants in Southeast Asia.

Orchidaceae are one of the largest families of angiosperms in terms of species richness.In the last decade,numerous studies have delved into reconstructing the phylogenetic framework of Orchidaceae,leveraging data from plastid,mitochondrial and nuclear sources.These studies have provided new in-sights into the systematics,diversification and biogeography of Orchidaceae,establishing a robust foundation for future research.Nevertheless,pronounced controversies persist regarding the precise placement of certain lineages within these phylogenetic frameworks.To address these discrepancies and deepen our understanding of the phylogenetic structure of Orchidaceae,we provide a comprehensive overview and analysis of phylogenetic studies focusing on contentious groups within Orchidaceae since 2015,delving into discussions on the underlying reasons for observed topological conflicts.We also provide a novel phylogenetic framework at the subtribal level.Furthermore,we examine the tempo and mode underlying orchid species diversity from the perspective of historical biogeography,highlighting factors contributing to extensive speciation.Ultimately,we delineate avenues for future research aimed at enhancing our understanding of Orchidaceae phylogeny and diversity.

Polyploidy is a major factor in the evolution of plants,yet we know little about the origin and evolution of polyploidy in intertidal species.This study aimed to identify the evolutionary transitions in three true-mangrove species of the genus Acanthus distributed in the Indo-West Pacific region.For this purpose,we took an integrative approach that combined data on morphology,cytology,climatic niche,phylogeny,and biogeography of 493 samples from 42 geographic sites.Our results show that the Acanthus ilicifolius lineage distributed east of the Thai-Malay Peninsula possesses a tetraploid karyotype,which is morphologically distinct from that of the lineage on the west side.The haplotype networks and phylogenetic trees for the chloroplast genome and eight nuclear genes reveal that the tetraploid species has two sub-genomes,one each from A.ilicifolius and A.ebracteatus,the paternal and maternal parents,respectively.Population structure analysis also supports the hybrid speciation history of the new tetraploid species.The two sub-genomes of the tetraploid species diverged from their diploid progenitors during the Pleistocene.Environmental niche models revealed that the tetraploid species not only occupied the near-entire niche space of the diploids,but also expanded into novel environments.Our findings suggest that A.ilicifolius species distributed on the east side of the Thai-Malay Peninsula should be regarded as a new species,A.tetraploideus,which originated from hybridization between A.ilicifolius and A.ebracteatus,followed by chromosome doubling.This is the first report of a true-mangrove allo-polyploid species that can reproduce sexually and clonally reproduction,which explains the long-term adaptive potential of the species.

土壤动物多样性及其影响的地表过程是陆地生态系统健康的重要基础.中国的土壤动物研究已走过70余春秋,在土壤动物群落的物种组成及地理分布格局等方面取得了丰硕成果.随着土壤动物生态功能日益受到重视,土壤动物生态地理学——作为土壤动物地理格局与生态系统服务的联系桥梁,迎来了新的发展契机.土壤动物地理学研究可分为4个维度:1)土壤动物群落表观特征的时空格局;2)土壤动物群落食性与习性等群落内在特征的时空格局;3)土壤动物相关的生物和非生物互作关系的时空格局;4)土壤动物相关或调控的关键生态过程的时空格局.传统的土壤动物地理学研究以土壤动物本身及其地理分布为焦点,为使其能更直接地与生态系统服务相联系,建议:1)从纯粹的生物地理学研究转向土壤动物群落相关或主导的重要"关系"和"生态过程"的时空格局研究;2)拓展土壤动物地理学研究的时空尺度;3)探究多尺度-多因子-多过程土壤动物相关数据的整合分析方法;4)构建土壤动物生态地理学研究的标准参照系.土壤动物生态地理学的研究目标是揭示土壤动物群落"生态位"变化规律,实现对土壤动物群落及其生态功能的精准调控,进而服务于生态系统健康和人类福祉.

海洋生物地理学是研究海洋生物地理分布时空格局、形成过程及其影响因素的学科,对于生物多样性保护、生态系统结构稳定以及海洋资源可持续利用具有重要支撑作用.物种分布模型是研究物种地理分布变化的重要手段,其发展对于海洋生物地理学的发展具有重要的推动作用.本文综述了中国海洋生物地理学的发展历程和现状;提供了物种分布模型的定义、类型、发展历程及相关重要数据库;整理分析了中国海洋生物地理学研究中的部分热点问题,主要涉及全球变化下海洋生物分布区变化、海洋生物谱系地理结构、海洋生物入侵、种群连通性、海洋保护规划、海洋生态修复、海洋生物对极端环境适应、海洋渔业资源管理和海水养殖规划等.本文同时对海洋生物地理学研究的未来发展进行了展望,强调了改进物种分布模型的重要性,提出要强化环境和生物数据库建设,加强海洋生物地理学与其他学科的交叉融合等.本综述对于今后我国海洋生物地理学的研究,尤其是物种分布模型在相关领域中的应用具有参考价值.

[目的]文章报道了云南省勐腊县中老边境地区舟翅桐属(Pterocymbium R.Br.)及其属下热带落叶大乔木——大花舟翅桐(P.macranthum Kosterm.)在中国的分布新记录.此外,还完善了其属和种的描述,评估了境内种群规模和濒危程度.[方法]利用体视显微镜对其标本进行解剖观察,并用数码相机对关键分类特征进行拍摄记录;利用无人机航拍对大花舟翅桐境内种群进行规模快速评估;采用访谈法并结合经验对其IUCN物种受威胁等级进行评估.[结果]大花舟翅桐在中国境内约有1 000株,分布区面积约2 000 hm2,建议将其评为IUCN红色物种名录易危(VU)物种.[结论]舟翅桐属为中国新记录属,属下大花舟翅桐为中国新记录种.该发现将其分布区向北扩展至热带亚洲北缘,有助于深入理解中国与东南亚热带植物区系之间的联系.

Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain elusive.Here,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelagoes in the South China Sea.We found positive plant species-area relationships for both coral and continental archipelagoes.However,our results showed that different mechanisms contributed to similar plant species-area relationships between the two archipelagoes.For coral islands,soil nutrients and spatial distance among communities played major roles in shaping plant community structure and species diversity.By contrast,the direct effect of island area,and to a lesser extent,soil nutrients determined plant species richness on continental islands.Intriguingly,increasing soil nutrients avail-ability(N,P,K)had opposite effects on plant diversity between the two archipelagoes.In summary,the habitat quality effect and dispersal limitation are important for regulating plant diversity on coral islands,whereas the passive sampling effect,and to a lesser extent,the habitat quality effect are important for regulating plant diversity on continental islands.More generally,our findings indicate that island plant species-area relationships are outcomes of the interplay of both niche and neutral processes,but the driving mechanisms behind these relationships depends on the type of islands.

Here,we infer the historical biogeography and evolutionary diversification of the genus Lilium.For this purpose,we used the complete plastomes of 64 currently accepted species in the genus Lilium(14 plastomes were newly sequenced)to recover the phylogenetic backbone of the genus and a time-calibrated phylogenetic framework to estimate biogeographical history scenarios and evolutionary diversification rates of Lilium.Our results suggest that ancient climatic changes and geological tectonic activities jointly shaped the distribution range and drove evolutionary radiation of Lilium,including the Middle Miocene Climate Optimum(MMCO),the late Miocene global cooling,as well as the successive uplift of the Qinghai-Tibet Plateau(QTP)and the strengthening of the monsoon climate in East Asia during the late Miocene and the Pliocene.This case study suggests that the unique geological and cli-matic events in the Neogene of East Asia,in particular the uplift of QTP and the enhancement of monsoonal climate,may have played an essential role in formation of uneven distribution of plant di-versity in the Northern Hemisphere.

青藏高原东缘地区作为高原横向扩展的前缘过渡带,地理环境与气候条件多样,是全球生物多样性研究的一个热点地区.蝉科昆虫长期在地下营固定生活,成虫发生期短、体型硕大、飞行能力弱而难以扩散,因此适合多尺度的生物地理学和物种多样性研究;但青藏高原东缘地区的蝉科昆虫区系一直缺乏研究.本研究在区系调查和系统分类研究基础上,对青藏高原东缘地区的蝉科昆虫多样性及地理分布格局进行了研究.结果表明,该地区共分布蝉科昆虫3亚科46属100种(包括2个新纪录种),分别占中国已知属、种数量的59.7％和29.1％;区系以东洋界成分为主(73种,73.0％),古北界和东洋界共有成分次之(21种,21.0％),特有成分比例较高(19种,19.0％).该地区的10个亚区可被分为南、北2个大区,大致以秦岭及甘南山地为界.北段的黄土高原过渡区(MX+HB)、藏北过渡区(QZ)属于古北界,物种多样性较低,分布的主要是体型较小的姬蝉亚科物种.南段的东洋界各亚区由秦岭西段山地过渡区(HZⅠ+XNⅠ)、川西盆地及滇北过渡区(HZⅡ+XNⅣ)、青藏高原东南部的横断山脉"高原-山地"过渡区(XNⅡ+XNⅢ)及滇西山地过渡区(HN)组成.各亚区的物种多样性由北向南逐渐增多,四川盆地西部和横断山南部为多样性中心.在南段的各亚区中,西南亚区Ⅰ(XNⅠ)和华中亚区Ⅰ(HZⅠ)区系相似性最高,华中亚区Ⅱ(HZⅡ)和西南亚区Ⅳ(XNⅣ)区系相似性最高,它们分别聚合后再与"西南亚区Ⅱ+西南亚区Ⅲ(XNⅡ+XNⅢ)"聚合,最后与滇西的华南亚区(HN)聚合,表明滇西的华南亚区(HN)及高原东南部的横断山脉"高原-山地"过渡带(XNⅡ、XNⅢ)区系相对独特.蝉科同一类群的不同物种在该地区呈现出明显的生态位分化,分别向"低山-峡谷-丘陵"生境和"亚高山-高山"生境发展."低山-峡谷-丘陵"分布的适热物种分布区比较广泛,均在相邻的东部、南部地区有所分布;"亚高山-高山"的适冷种类则多局限分布于高海拔地带(许多都是特有种),尤其在横断山脉地区基本都呈现为小范围的斑块或点状分布,即"天空岛"分布格局.整体而言,青藏高原东缘南段的高大山体、相关地带的急剧下降地形及气候差异等对蝉科物种的扩散和分布影响更大,研究结果为青藏高原邻近地区的动物地理区划及生物多样性分化研究提供了新的信息和参考依据.