ABSTRACT The Eastern Spotted Dove (Spilopelia chinensis) is a widespread human‐commensal bird, frequently involved in wildlife law enforcement cases. Following such cases, confiscated individuals are often released back into the wild, yet the potential genetic impacts of these releases remain unclear due to limited understanding of the species' population genetic structure in China. This study aimed to assess the genetic diversity and population structure of Eastern Spotted Doves in Jiangsu Province to provide a scientific basis for the management of confiscated individuals. This study analyzed the genetic diversity and structure of 139 individuals from 13 sampling sites across five avian geographical regions in Jiangsu Province, China, using mitochondrial cytochrome b (Cytb) and Displacement loop (D‐loop) sequences, and explored the impact of urbanization on genetic differentiation. A total of 49 haplotypes were detected. The samples exhibited high haplotype diversity (Hd = 0.896) but low nucleotide diversity (pi = 0.00216). The maximum likelihood phylogenetic tree showed that no geographical clustering, and the haplotype network displayed a star‐shaped topology with core haplotypes shared across all regions. AMOVA revealed that genetic differentiation among groups was negligible and non‐significant, regardless of grouping by geography or urbanization level. Pairwise Fst values were close to zero and non‐significant, while gene flow estimates (Nm) exceeded 28 in all comparisons. These findings indicate that the Eastern Spotted Doves in Jiangsu Province lack significant population genetic structure, with strong gene flow maintained across regions. The species' high adaptability to urban environments and dispersal capacity likely sustain genetic connectivity. From a mitochondrial genetic perspective, the in situ or proximate release of confiscated individuals within Jiangsu Province poses minimal genetic contamination risk. However, validation using nuclear markers, such as microsatellites or single nucleotide polymorphisms, is recommended.

Extremely small and isolated remnant populations represent an overlooked but critical conservation challenge for many threatened plant species. Although such populations may still be recorded as extant, demographic collapse and regeneration failure often place them at high risk of local extinction. Here we report the rapid decline of a micro-population of Glyptostrobus pensilis, a globally threatened relict conifer, discovered in a sacred forest associated with the millennium-old Nanhua Temple in southern China. Field observations identified only nine mature individuals, all of which were centuries old and showed signs of physiological deterioration. At least two trees had already died, and no seedlings or saplings were observed, indicating long-term recruitment failure and demographic non-viability. Despite its location within a culturally protected landscape, the population lacks ecological management and habitat restoration. This case highlights the limitations of passive protection and illustrates the risk of “invisible extinction” in sacred or cultural refugia. We argue that micro-populations should be recognized as high-priority conservation units and recommend the establishment of monitoring thresholds, emergency demographic interventions, habitat restoration, and integration of cultural landscapes into science-based conservation strategies.

The red-eared slider (Trachemys scripta elegans) is a globally recognized invasive alien species. First introduced to China in the 1980s, it is now distributed across all mainland provinces. Despite its designation as a prohibited invasive species, intentional releases remain common, largely due to its widespread availability and a critical lack of public awareness regarding its ecological impact. The commercial trade of this turtle is a key driver of this issue. Therefore, targeting the supply and sale of these animals is proposed as a critical intervention point. A tripartite management framework is recommended, encompassing institutional improvement, consumption guidance, and sales regulation.

The large old tree population of Barringtonia racemosa (L.) Spreng plays a crucial ecological and cultural role in rural areas (Danzhou, tropical China). This study investigates the population structure, demographic characteristics, and conservation status of B. racemosa in remnant forest stands. The findings reveal a skewed distribution towards smaller to intermediate-size classes, with a significant decline in larger-size classes. The static life table highlights high mortality rates in the early stages and moderate survivorship in mid-size classes, indicating a bottleneck in the transition from medium to larger-size classes. The study identifies external interference as a potential threat to the B. racemosa population. Based on these findings, a multifaceted conservation approach is proposed to integrate traditional ecological knowledge, implement community-based conservation programs, enhance habitat protection and restoration, and strengthen legal protection and policy support. This research underscores the critical role of large old trees in ecosystem health. It highlights the need for targeted conservation strategies to preserve these vital components of natural landscapes in rural China.

Background Magnolia zenii Cheng, an endemic and critically endangered species, is restricted to Baohua Mountain, Jiangsu Province, China. Despite the implementation of in situ conservation measures implemented after the establishment of Baohua Mountain Nature Reserve in 1984, the species continues to face significant regeneration challenges. New information This study evaluates the population structure and regeneration dynamics of M. zenii using data from field surveys conducted in 2001 and 2024. Our findings indicate a substantial increase in the total population size from 34 to 115 individuals and a broadening of the size-class distribution. However, persistent gaps in recruitment, particularly the absence of individuals in the smallest diameter class (< 5 cm), highlight critical reproductive and establishment constraints. Factors limiting regeneration include poor seedling establishment due to reproductive inefficiencies, intense competition from Phoebe sheareri and Phyllostachys edulis and anthropogenic impacts associated with tourism management. We propose a multi-faceted conservation strategy emphasising enhanced reproductive management, mitigation of competitive pressure and science-based tourism control to promote sustainable population recovery. This study provides a comprehensive framework for addressing regeneration constraints and providing information for long-term conservation policies for M. zenii and other endangered species with similar ecological challenges.

The Yangtze River is China’s essential ecological resource and a historically revered “mother river” intimately tied to her ancient civilization. In recent years, the river has faced escalating threats from non-native fish species introduced by anthropogenic activities, including prayer animal release, aquaculture escapes, and deliberate pet abandonment. With a low current population density, these exotic species pose limited immediate ecological risks. However, the ecological damage will be catastrophic in the long run once they successfully establish large and stable populations and become invasive. To effectively address this challenge, comprehensive measures can be applied, including strengthening risk assessment, controlling reproduction and transmission, suppressing new introductions, improving regulations and policies, enhancing public education and prevention awareness, and strengthening multi-party cooperation. This study contributes new insights into the dynamics of invasive species in the Yangtze River and the broader implications for freshwater ecosystem management by reviewing current knowledge.

Heritage trees, as vital bioresources, enhance urban ecosystems and cultural heritage in Lingshui, Hainan, China. Yet, urbanization and environmental shifts threaten their persistence, necessitating detailed studies for conservation. From 2023 to 2024, the authors surveyed 133 heritage trees across 18 species, 14 genera, and 10 families. Tamarindus indica L. dominated (importance value 37.60), followed by Ficus microcarpa L. f. (14.37) and Bombax ceiba L. (12.55), comprising 64.52% of the total importance value. Diversity varied across twelve towns, with Yingzhou showing the highest despite fewer trees. Most trees, aged 100-150 years with 60-150 cm diameters, indicated an aging population. Kernel density mapping revealed central-eastern distribution hotspots, hinting at historical or environmental influences. Termite infestation (45.1%) and trunk decay (36.4%) were primary threats, with pests and diseases less impactful (6.8%). Compared to other Hainan cities, Lingshui’s lower tree diversity reflects topography, typhoons, and human pressures including urbanization and agriculture. Targeted conservation addressing biological and socioeconomic factors is critical to sustain these bioresources, which support biodiversity through microhabitats, ecological continuity, and genetic diversity in urbanizing landscapes.

Large old trees (LOTs) are invaluable natural treasures and cultural legacies, holding ecological, historical, social, and economic significance. However, climate change and human impacts threaten their existence. Understanding their species composition, age structure, biomass, and distribution patterns in relation to environmental factors is essential for effective conservation. In Hainan Island, South China, we analyzed 1081 LOTs from 74 species across 35 families, using a combination of field surveys and government data. The dominant families were Moraceae, Sapindaceae, and Fagaceae, with key species including Ficus altissima, Litchi chinensis, and Tamarindus indica. The age distribution followed a reverse J-shape, indicating a prevalence of trees aged 300-399 years. In contrast, diameter at breast height (DBH) and height distributions were unimodal, favoring medium to large-sized trees. Spatial analysis revealed uneven distribution patterns: the western zone exhibited the highest species diversity, the central zone moderate diversity, and the eastern zone low diversity, reflecting uneven urban and agricultural impacts. Most LOTs were concentrated at elevations of 0-50 m. Factors such as GDP, urbanization, and forest cover positively correlated with LOT abundance and diversity, with forest cover and average annual temperature particularly favoring these trees. The findings emphasize the intricate relationship between environmental factors and LOT distribution. They advocate for tailored conservation strategies that address the complex interplay of ecological, socioeconomic, and cultural influences on their preservation.Abstract in Chinese is available with online material.

Large old Ginkgo biloba trees (LOGTs), with profound ecological and cultural significance in China, face increasing threats from climate change and human activities. We employed the BIOCLIM and DOMAIN species distribution models to predict their spatial patterns under the present climate and doubled-CO2 climate change scenario in 2100. We collected 604 validated LOGT occurrence records and data on 19 bioclimate factors for the analysis. Our study yielded a LOGT geographic distribution pattern covering a wide latitudinal belt extending from south subtropical to temperate zones in central and eastern China, concentrating in low elevations and coastal regions. The principal component analysis identified the dominant bioclimatic factors shaping their distribution, namely annual precipitation and low winter temperatures. BIOCLIM and DOMAIN generated predicted suitable habitats that match the present distribution range well. However, under the future climate scenario, the models indicated habitat retentions mainly in the core distribution areas and habitat losses mainly in the southern edge of the present range and scattered pockets elsewhere. Some retained habitats, including excellent ones, will suffer from fragmentation. The predicted new habitats may permit some range expansion and migration but are beset by small patch size and large interpatch distance, bringing fragmentation and gene flow restrictions. The anticipated projected range decline highlights considerable threats climate change poses to the long-term survival of the precious natural-cum-cultural resource. Understanding the distribution patterns and underlying drivers and distillation of practical conservation measures can foster sustainable management vis-a-vis the looming global change.

Urban green roofs have emerged as an innovative nature-based solution for enhancing urban sustainability and resilience. Based on the Web of Science Core Collection database, the scholarly papers on green roofs published in the past two decades were analyzed quantitatively and visualized using bibliometric techniques. The study scope covered research countries, institutions, main journals, crucial authors, highly cited documents, hot topics, and research frontiers. The 3210 publications mined from the bibliographic database on green roofs have increased progressively in the study period, with a significantly faster pace in recent years. The research subjects changed gradually over time, extending into more disciplines and becoming decidedly multidisciplinary. The notable bibliometric features registered a pronounced spatial concentration of research outputs in a small number of countries, regions, research institutions, journals, and researchers, mainly associated with developed metropolises. The number of publications and citation impacts identified the world’s top ten researchers and journals. Well-defined clusters depicted by knowledge graphs indicated a diverse range in the number and strength of inter-node connections for countries, institutions, researchers, and research topics defined by keywords. The research scope focuses on quantifying benefits and costs and optimizing designs to maximize biodiversity, hydrologic, thermal, and energy benefits as urban sustainability and climate-adaptation solutions. Emerging research should enhance biodiversity through optimal plant selection, integrate green roofs with renewable energy systems for sustainability, apply computational tools to enhance designs, evaluate low-cost and locally relevant design options for developing cities, and quantify co-benefits like stormwater reduction and energy savings. Multidisciplinary efforts leveraging simulations, ecosystem services valuation, and participatory community partnerships can advance context-appropriate green roof innovation and evidence-based policymaking to expand adoption in cities worldwide. Quantifying and communicating co-benefits are critical measures to drive wider implementation.

We sequenced and analyzed the complete mitochondrial genome of Lentipes ikeae and explored the phylogenetic relationships among Sicydiinae based on mitochondrial genome sequences. The complete mitochondrial genome sequence of L. ikeae was determined using the Illumina HiSeq X Ten sequencing platform, and the gene structural characteristics and base composition were analyzed. Based on the mitochondrial genome sequences of 28 Sicydiinae species published in GenBank and mitochondrial protein-coding genes (PCGs), Acanthogobius flavimanus (Gobionellinae) was selected as an outgroup to construct phylogenetic trees of Sicydiinae using the maximum likelihood and Bayesian inference methods. The mitochondrial genome of L. ikeae (GenBank number: OP764680) has a total length of 16,498 bp and encodes 13 PCGs, 22 transfer RNA genes, two ribosomal RNA genes, and a D-loop (control) region. Gene rearrangement is not observed. The mitochondrial genome of L. ikeae exhibits an AT preference, with AT skew > 0 and GC skew < 0 across the entire genome. The phylogenetic relationships of Sicydiinae based on 13 mitochondrial PCG sequences are Sicydium + (Stiphodon + (Sicyopus + Lentipes)) + Sicyopterus, indicating that Sicydium, Sicyopterus, Lentipes, and Stiphodon are all monophyletic groups.

Ecosystem services offered by urban forests must be proactively managed to remain diverse and sustainable. Recent research findings deserve a systematic synthesis to elucidate inherent knowledge structures and dynamics. This study focused on the urban tree diversity theme from 2000 to 2022. Web of Science Core Collection database provided bibliometric details on academic publications. The data-driven quantitative analysis explored research quantities, emphasis, trends, patterns, linkages, and impacts by countries, institutions, authors, journals, and citations. Publications and research topics have expanded continually, with accelerated growth in recent years. Research activities, outputs and interactions demonstrated conspicuous spatial clustering. A few countries, institutions and researchers generated a notable proportion of publications. Their scholarly contributions were visualized in knowledge graphs as complex networks of nodes and inter-node links. Keyword analysis generated a network to indicate research hotspots and frontiers to steer and prioritize future studies. Recent findings affirmed that cities can harbor substantial tree diversity due to enhanced habitat heterogeneity and successful species adaptation. Aligning tree traits with environmental conditions and management objectives can improve benefits. Urbanization can filter tree traits to shape community assemblages through stressors: habitat degradation, fragmentation and loss, in conjunction with pollution, climate change, and introduced species. Diversity preservation strategies include protecting remnant natural vegetation, connecting green spaces, and restoring complex canopy geometry and biomass structure. The emerging frontiers are marked by modeling future species distributions, leveraging technologies like remote sensing, linking ecology with human values, and committing to community-based stewardship. Management can be upgraded by interdisciplinary perspectives integrating ecological science and social engagement. The findings highlight the need for biodiversity enrichment anchored by native species, trait-matched assemblages, adaptive policies, and community participation to create livable-green cities. This review synthesizes key advances in urban tree ecology and biodiversity research to inform the planning and stewardship of resilient urban forests.

Despite their relatively small numbers, large old trees play disproportionately important roles in global biodiversity and ecosystem functions. There is a lack of systematic reviews and quantitative analyses of the accumulated literature. Understanding the research context and evolution could pump prime research and conservation endeavors. Using the comprehensive Web of Science, we applied VOSviewer (1.6.19) and CiteSpace (6.1R2) bibliometric software to examine the large old tree research field in 2000–2022. The queries of the bibliographic database generated quantitative–visual depictions in the form of knowledge maps. The nodes denote research intensity, and inter-node linkages denote the pathways and frequencies of collaborative activities. The research outputs differed significantly in terms of regions, countries, institutions, high-citation articles, productive researchers, hot topics, and research frontiers. Conspicuous spatial disparities were displayed, with the U.S.A., China, and Australia leading in publication counts and a cluster of European countries making considerable collective contributions. The research collaboration demonstrated a dichotomy: European countries networked more by geographical propinquity, and the top three countries connected by long-distance leap-frog jumps. The entrenched discrepancies between the endowed developed domains vis-à-vis the deprived developing domains were clearly expressed. The research productivity progressed through three stages: initial, growth, and flourishing. The leading institutions, researchers, and highly cited papers were recognized. The keyword analysis pinpointed diverse research hotspots: growth dynamics, conservation and management, ecological functions, and environmental response. This study informs recommendations for future research directions and cooperation on longevity mechanisms, evolutionary adaptation, dynamic monitoring, and temporal–spatial patterns. The integrated application of GIS, machine learning, and big data technologies could strengthen research capability.

Large old trees (LOTs) are important ecological assets that contribute significantly to biodiversity, ecosystem functioning and local culture. This study analyzed the abundance, species composition, spatial and altitudinal distribution patterns, and conservation needs of LOTs in Baisha County, tropical southern China. We conducted a comprehensive field survey of 301 LOTs and recorded their biological characteristics, geographical locations, and environmental conditions. Species importance values were calculated, and the spatial distribution was analyzed using GIS techniques. Redundancy analysis (RDA) examined the relationships between LOT diversity and environmental factors. The results indicated a complex and diverse stock dominated by species from the Moraceae family, particularly of the genus Ficus. The structural analysis displayed a skewed age distribution, with a higher frequency of younger trees and a decline in older classes. Spatial analysis showed that LOTs are concentrated in the northwestern and central areas and are favored by microclimatic conditions, soil types, and historical land-use practices. The abundance and species richness of LOTs were greater at intermediate elevations. Redundancy analysis highlighted the intricate relationships between LOT diversity, abundance, and socioeconomic factors. This study provided crucial insights into the ecology and conservation requirements for LOTs in Baisha. The findings underscored the importance of targeted conservation efforts, particularly for older trees and mid-elevation habitats. We recommended integrating ecological research, long-term monitoring, traditional ecological knowledge, and community involvement in formulating conservation strategies to preserve these ecologically and culturally significant trees for future generations.

Alligator gar Atractosteus spatula originates from North America but has been introduced into China recently. Considered an invasive fish, it may cause losses in the diversity and number of local species and in fish catch due to its predation on numerous aquatic animals in non-native habitats. A comprehensive study of this alien invasive species' existing spatial patterns in relation to climatic variables is critical to understanding the conditions amenable to its distribution and controlling its further spread into potential range areas. We used MaxEnt and QGIS species distribution modeling to estimate the likely biogeographical range of A. spatula in China based on 36 validated distribution records and seven selected environmental variables. The highly suitable area was found primarily in a series of provinces extending from inland to coastal regions, covering southwest to south, central and east China. The model identified the minimum temperature of the coldest month (Bio6) and mean temperature of the warmest quarter (Bio10) as the strongest predictors of A. spatula distribution. The findings could offer scientific guidance for managing and preventing the spread of this invasive fish and hint at controlling invasive aquatic fauna.

Climate change jeopardizes species survival, particularly for endangered species. This risk extends to the endangered Chinese endemic tree Tapiscia sinensis. The factors underpinning T. sinensis’s habitat distribution are poorly understood, and its potential response to future climate scenarios remains unclear. With six shortlisted climate factors and 117 occurrence records, we modeled T. sinensis’s potential distribution across China using the BIOCLIM model. We applied principal component analysis to examine the primary climate factors restricting its geographical range. The findings indicate that T. sinensis’ range is principally located in China’s middle subtropical climatic zone at low–mid altitudes. The principal component analysis identified two critical factors representing temperature and precipitation. Temperature was the most critical factor limiting T. sinensis distribution, especially the effect of temperature seasonality and isothermality. The habitat suitability model generated by BIOCLIM under current climate conditions demonstrated strong concordance between the predicted suitable areas and the present actual distribution range. These results verify that the model can reliably identify habitats conducive to T. sinensis growth and survival. However, under a hypothetical future climate scenario of doubled atmospheric CO2 concentrations for 2100, the model indicates a precipitous reduction and fragmentation in the areas with excellent suitability conditions. This predicted decline highlights the considerable threats posed by climate change to the long-term survival of this endangered species in China. Our habitat modeling yields critical insights that inform the development of science-based strategies and best practices to improve conservation management plans for research, protection, nursery cultivation, and sustainable planting in China. Habitat suitability knowledge could aid introduction and cultivation efforts for T. sinensis globally in places with analogous climates.

SummaryThe coniferous shrub Oliver’s plum yew (Cephalotaxus oliveri) is endemic to southern China with potential medicinal use for cancer treatment and ecological value in sustaining China’s threatened subtropical forest ecosystems. Comprehensive understanding of the current spatial patterns of this vulnerable species vis-à-vis climatic conditions is crucial for its sustained economic use and conservation. Based on 100 reliable occurrence records and nine environmental variables, MaxEnt and QGIS programs were used to predict the potential geographical distribution of C. oliveri in China. Combined with percentage contribution and permutation importance, the jackknife statistical method was used to test and evaluate pertinent factors restricting the potential distribution of C. oliveri. The response curves of critical bioclimatic factors were employed to determine the potential species range. The current core potential distribution areas were concentrated in China’s central and south-west regions. Temperature was identified as the crucial determinant of species distribution patterns, particularly the mean temperature of the coldest quarter. Precipitation was a necessary but not critical secondary factor. These findings should inform the ex situ conservation and cultivation of C. oliveri in China and its introduction to other parts of the world for similar purposes.

Old trees play important roles in maintaining biodiversity, ecological balance and environmental protection.To conserve the old tree community of Taxus wallichiana var. mairei in Liancheng county, Fujian province, the species composition and structure of the community were analyzed using the method of sample survey. There were 74 vascular plants belonging to 66 genera of 41 families, in which most were monotypic genus. Rosaceae, Gramineae, Hamamelidaceae and Lauraceae were the four families with the largest number of species in this community. There were 12 genus areal-types in the community, which was consistent with the location of the community with the ratio of tropical element to temperate element（T/R） 1.03. The important values of T. wallichiana var. mairei, Phyllostachys edulis, and Cunninghamia lanceolata in arbor layer of this community were relatively high, which was 50.76%, 14.33% and 6.61%,respectively, while those of Camellia fraternal, Loropetalum chinense and Photinia davidsoniae in shrub layer were relatively high, which was 4.07%, 3.91% and 3.60%, respectively. In herb layer, Stellaria media, Dicranopteris linearis,and Miscanthus sinensis were the top three with importance values 13.30%, 10.33% and 9.82%, respectively. The vertical structure of this old tree community was clear,and it could be divided into three layers for arbor,shrub,and herb layers within few interlayer plants. T. wallichiana var. mairei was the dominated species in the uppermost layer. The old tree community of T. wallichiana var. mairei in Liancheng had important conservation value; however, young trees and seedlings of T. wallichiana var. mairei were missing in this community due to the constraints of human interference and interspecific competition. It is a feasible strategy to protect this community by constructing a fengshui forest with T.wallichiana var. mairei as the main body based on the scientific management.

Ormosia hosiei is an endemic plant in China listed as a national grade II key protected wild plant with important scientific, economic, and cultural values. This study was designed to predict the potential suitable distribution areas for O. hosiei under current and future climate change and to provide a reference to enhance the species’ conservation and utilization. Based on the actual geographical locations of O. hosiei in Sichuan, we applied two species distribution models (BIOCLIM and DOMAIN) to predict its current and future potential suitable areas and future change patterns. We also analyzed the major climatic variables limiting its geographical distribution with principal component analysis. The results indicated that O. hosiei was mainly distributed in the eastern region of Sichuan and concentrated in the middle subtropical climate zone at relatively low elevations. The principal component analysis identified two critical factors representing temperature and moisture. The temperature was the most critical factor limiting O. hosiei distribution in Sichuan, especially the effect of extreme low temperatures. Both models’ simulation results of potential suitable areas under the current climate scenario showed that the excellent suitable habitat was consistent with the current actual distribution, remaining in the eastern region of Sichuan. Under the future climate scenario with doubled CO2 concentration (2100), both models predicted a sharp decrease in the areas of excellent and very high suitable habitats. The findings can inform strategies and guidelines for O. hosiei research, conservation, nursery production, and cultivation in Sichuan.