Aims: Landscape pattern is an important driving factor that influences changes in plant species diversity (PSD) and plant functional diversity (PFD). The Hunshandak Sandland, a region in Inner Mongolia, is characterized by a variety of sand dunes, lakes, and built-up areas to form a complex and evolving landscape, which presents an ideal area to elucidate these mechanisms.
Methods: In this study, we processed remote-sensing images from 2008-2017 from the study area and conducted field surveys and analysis to investigate PSD and PFD. Spearman correlation analysis and general linear mixed model were employed to identify landscape pattern indices that significantly contributed to PSD and PFD. Furthermore, a structural equation model was utilized to determine both the direct and the indirect effects of dynamic changes in the landscape pattern on PSD and PFD.
Results: The results indicated that both PSD and PFD were influenced by landscape patterns from the previous 2-4 years. We discovered that PSD was primarily influenced by shape index, area and edge index, and aggregation index and were relevant in different timescales and land use types. PFD was predominantly affected by shape index and aggregation index.
Conclusion: The dynamics of landscape pattern must be considered in the process of landscape planning, management, and conservation of biodiversity in arid and semi-arid lands in Inner Mongolia and could be translated to similar regions worldwide.

Aims: The City Wall of Sanxingdui is a historical site of great significance to the exploration of the origins of Chinese civilization. It is important to study the relationships between herbaceous plant species diversity, root system and soil anti-scourability under different maintenance measures to protect this valuable cultural site from erosion damage and harness the water and soil conservation functions of native vegetation.
Methods: In this study, we conducted a field survey focusing on five typical herbaceous plant communities associated with five common maintenance measures at Sanxingdui City Wall: natural regeneration, planting, abandoned field, shrub removal, and pruning. We investigated the species diversity, root characteristics, soil anti-scourability and their correlation.
Results: A total of 103 species of herbaceous plants belonging to 40 families and 81 genera were recorded in the study area, with Asteraceae and Gramineae being dominant families, and the majority of species being perennial herbs. Species diversity was highest in the shrub removal plots, followed by the natural regeneration plots, and then the pruning and planting plots, while the abandoned field plots had a significantly lower level of species diversity than the other types of plots (P < 0.05). The soil anti-scourability coefficients of the shrub removal and natural regeneration plots (138.86 L/g and 118.31 L/g) were not significantly different (P > 0.05), but both were significantly higher (P < 0.05) than the other types of plots. Root characteristics demonstrated a more robust root network in shrub removal plots, with significantly higher values of root surface area density, root volume density and average root diameter than other types of plots (P < 0.05). The four diversity indices (Shannon-Wiener diversity index, Simpson dominance index, species richness index, Pielou evenness index), root length density, average root diameter and number of root branches were very significantly positively correlated with the soil anti-scourability coefficient (P < 0.01). Root surface area density and root volume density were also significantly positively correlated with soil anti-scourability coefficient (P < 0.05).
Conclusions: In summary, the shrub removal and natural regeneration plots demonstrated higher herb diversity indices, denser root networks and greater soil anti-scourability coefficients. Considering the vegetation characteristics of the city walls and the importance of preserving this unique cultural heritage site, we recommend implementing in situ habitat protection measures with a focus on natural regeneration, supplemented by scientifically informed active maintenance measures such as shrub removal and pruning when necessary. This strategy holds promise to effectively enhance species diversity and soil anti-scourability, and promote sustainable development and historical preservation of the walled vegetation of the Sanxingdui site.

Aims: Metamorphosis is a common character of insect development, wherein larval and adult insects exhibit significant differences in their resource requirement and utilization efficiency. Exploring the variations in niche and fitness difference in different development stages among competing insects can enhance our comprehension of insect species coexistence and community formation. Drosophila melanogaster and D. immigrans, two widely distributed Drosophila species, cohabit during the same season and both feed on decaying fruit. This study aims to explore the shift in ontogenetic niche and fitness difference between these two Drosophila flies, thereby undercovering the underlying mechanisms that facilitate their coexistence.
Methods: We set up microcosm experiments to estimate the inter- and intra-species competition coefficients, and the niche overlap and fitness difference of two Drosophila species. We then investigated the resource competition between adult flies for oviposition sites and between larval flies for food resources. Ultimately, we analyzed the probability of coexistence between the flies in their larval and adult stages using modern coexistence theory.
Results: The results showed that D. melanogaster exhibited greater fitness than D. immigrans and possessed a higher probability of winning in competition. Furthermore, adult D. immigrans demonstrated superiority in competing for oviposition sites compared to D. melanogaster, while larval D. melanogaster displayed higher nutrient efficiency than D. immigrans. However, there is significant overlap in the resources required by both species during their adult and larval stages. The competition outcomes in both larval and adult stages were predominantly determined by the sequence of resource access.
Conclusions: According to our competition experiments involving two Drosophila species, we have made an intriguing observation: two species can exhibit excellent competitive abilities during different developmental stages, seemingly enhancing the coexistence of these species. However, the presence of substantial niche overlap, leading to priority effects among the competing pairs, ultimately prevents their coexistence. Furthermore, the diverse competition strategies employed by the two Drosophila species offer an explanation for the victor in cases involving priority effects. Consequently, our findings provide valuable insights into the significance of developmental stages and phenotypic plasticity in species coexistence.

Aims: The relationship between the elevation and biodiversity has long been one of the central issues in ecology, biogeography and conservation biology. This study investigate the diversity of birds and mammals and their elevational distribution, based on infrared camera monitoring in Guangdong Nanling National Nature Reserve, China.
Methods: We utilized infrared cameras to monitor the mammals and birds across the entire elevation of the Guangdong Nanling National Nature Reserve for 10 consecutive years. In addition, we also analyzed the current diversity and conservation status of birds and mammals. By combining both horizontal and vertical distribution patterns, we conducted hotspot and vacancy analysis to assess the diversity patterns of birds and mammals.
Results: Between 2012 and 2021, a total of 116 camera sites were deployed, capturing 85,164 days of work, and obtaining 21,194 identifiable independent and valid photos. Over this period, 24 mammal species and 50 bird species were recorded, with a relatively high proportion of threatened mammals at 45.83%. The top five mammals with the highest relative abundance index (RAI) were Muntiacus vaginalis, M. reevesi, Dremomys pyrrhomerus, Melogale moschata, and Macaca thibetana. However, Herpestes javanicus and Rusa unicolor were only recorded once and have the lowest RAI. The top four birds with the highest RAI were Lophura nycthemera, Myophonus caeruleus, Tragopan caboti and Arborophila gingica. Forty-two bird species had RAI less than 1, mainly belonging to Passeriformes, Piciformes and Strigiformes. The generalized additive model showed that the richness of mammals and birds were significantly related to elevation, displaying a typical “single-peak pattern” with a significantly high species richness at mid-elevation (around 1,000-1,400 m). Beta diversity analysis showed that the classification differences between the low and high elevational range and other sites were the highest, while the differences between the middle elevational sites were relatively small. Hotspot and vacancy analysis, integrating horizontal and vertical distributions, revealed that the mammals and birds in the reserve were mainly concentrated in three hotspots, distributed in the middle and high elevation. In addition, it was observed that certain areas outside of the reserve also exhibited a high diversity of birds and mammals. In conclusion, wildlife within the reserve continues to face severe protection pressure.
Conclusion: Regarding the construction of Nanling National Park, we suggest that the local management organization should: (1) Formulating conservation and management policies for key protected species in the future, especially for large and medium-sized mammals. (2) Focusing on the habitat management in the middle and high elevational areas, and maintain the complete climate and biological vertical zone in the reserve. (3) Establishing a multitrophic biodiversity monitoring system, which emphasis the effect of comprehensive factors on wildlife, such as human disturbance, environmental factors, functional traits, species interaction networks, and evolution history.

Aims: Habitat fragmentation and loss caused by urbanization are important factors that threaten the survival of wildlife globally. Urbanization has caused amphibians to become one of the most severely threatened groups of terrestrial vertebrates. Studying the spatial distribution pattern and exploring how landscape connectivity affects the gene flow among fragmented populations of amphibians in urban areas would provide a deeper understanding of the impacts of urbanization on wildlife and offer theoretical guidance for local biodiversity conservation.
Methods: In this study, we selected the eastern golden frog (Pelophylax plancyi) as the primary research subject and obtained landscape and environmental data about land cover, normalized difference vegetation index (NDVI) and land surface temperature in the Shanghai region using Landsat-8 satellite images (http://www.gscloud.cn). Combined with the data from field population survey, we employed the maximum entropy (MaxEnt) model to predict the spatial distribution pattern of P. plancyi in the region. We evaluated the potential corridors and calculated the resistance distances between local populations using circuit theory (Circuitscape), and explored the effect of geographical and resistance distance on genetic differentiation among local populations using the Mantel test of each local populations based on the genetic distance (F_ST) matrices calculated from simple sequence repeat (SSR) and single nucleotide polymorphism (SNP).
Results: The habitat suitability of P. plancyi significantly decreased along the rural-to-urban gradient. NDVI was the main factor affecting the MaxEnt modelling and indicated that the P. plancyi prefer to inhabit areas with higher vegetation coverage. There was no significant correlation between genetic distance and geographical distance, while genetic distance increased significantly with the resistance distance.
Conclusions: The protection and maintenance of continuous suitable habitats in suburbs and isolated habitat patches in urban areas that still exist is the primary measure of conservation for native amphibians such as P. plancyi. Furthermore, optimizing urban landscape structure, strengthening the construction of corridors suitable for various groups of wildlife, and promoting the gene exchange among local populations are effective methods to achieve the self-sustainment of populations and long-term conservation of biodiversity in urbanized areas.

Aims: The Chishui River basin in the upper reaches of the Yangtze River harbors a rich array of macroinvertebrate diversity. While the area’s importance has been acknowledged and is included in the National Rare and Endemic Fish Nature Reserve, our understanding of its macroinvertebrate diversity and dynamics remains limited. Importantly, continuous, seasonal macroinvertebrate surveys of the entire Chishui River basin have not been undertaken. To address this shortcoming, we conducted a comprehensive analysis of species diversity in this system and updated the species list based on the combined datasets of 2019-2021 seasonal investigations.
Methods: Macroinvertebrates were sampled from the main stream and tributaries in autumn (October 2019), winter (December 2019), summer (July 2020) and spring (March 2021). One-way ANOVA was used to examine the differences of abundance, biomass and ecological indices between different reaches and different seasons. Principal co-ordinates analysis (PCoA) and PERMANOVA were adopted to test the variation of community structures among different reaches and seasons. Redundancy analysis was applied to identify the key environmental factors and spatial factors that significantly influence the community structure of macroinvertebrates. The potential drivers of observed community patterns and proposed protective strategies and actions were subsequently identified.
Results: A total of 209 species of 186 genera and 86 families in 22 orders and 5 phyla were recorded with the exclusively dominant species being aquatic insects: Ephemera sp., Heptagenia sp., Polamanthus sp., Baetis sp., Naucoridae sp. and Polypedilum sp. Indexes of species richness, abundance and measures of diversity (Shannon-Wiener diversity index, Simpson dominance index, Pielou evenness index) revealed substantial spatial-temporal differences, with the largest in spring and in the upstream region. PCoA showed that the macroinvertebrate community structure varied significantly between seasons and sections of the river. Redundancy analysis (RDA) showed that five environmental (substrate, altitude, velocity, dissolved oxygen, NH₄⁺-N) and four large-scale spatial factors (PCNM1, PCNM2, PCNM3, PCNM6) were the key drivers underpinning community variation. Variation partitioning analysis indicated that environmental filtering had a stronger effect on community variation than spatial structuring.
Conclusion: To rehabilitate and protect the river’s macroinvertebrate diversity, we recommend the implementation of multiple protective strategies and preventive actions. These include at the very least, the introduction of a ten-year fishing ban, continuous afforestation practices, and regulation of illegal mining and liquor-making industries to promote recovery of the natural hydrological rhythm and riparian zones. State-of-the-art methods to prevent and control invasive alien species, and the establishment of effective prediction and risk evaluation mechanisms are also recommended.

Aims: Revealing the differences in species and metabolic functional groups of endophytic bacterial communities between tropical woody Fabaceae and Lauraceae plants, as well as their driving factors, contributes to understanding the adaptation and biodiversity maintenance mechanisms of tropical forests.
Method: In this study, Illumina Miseq sequencing platform was used to detect endophytic bacteria in Fabaceae and Lauraceae plants in the tropical mountain rainforest of Jianfengling in Hainan, and the FAPROTAX microbial geochemical cycle metabolic functional database was used to annotate the endophytic bacterial function.
Results: A total of 1,123 operational taxonomic units (OTUs) of endophytic bacteria belonging to 21 phyla, 36 classes, 51 orders, 92 families, and 160 genera were detected from four plant species, including two species (Ormosia semicastrata, O. balansae) of Fabaceae and two species (Cryptocarya chinensis, C. chingii) of Lauraceae. Among them, 600 OTUs were Proteobacteria, accounting for 57.17% of the total bacterial sequences, and 72 OTUs were Acidobacteria, accounting for 15.12%. The bacterial species of the Hymenobacter of Cytophagales, and Methylobacterium of Rhizobiales were the most abundant, with 37 and 27 OTUs, respectively. There were significant differences in endophytic bacterial species composition between Fabaceae and Lauraceae plants (ANOSIM: R = 0.5792, P = 0.004). The results of the environmental vector fitting analysis based on community non-parametric tests showed that the leaf potassium content and specific leaf area had the greatest impact on the species composition of endophytic bacterial communities. Endophytic bacteria with clear classification information, accounting for 54.63% total number of bacterial OTUs, were annotated to 28 metabolic functional groups. Of these functional groups, nitrogen fixation, aerobic chemoheterotrophy, cellulose degradation, methanol oxidation, methane oxidation, and urea degradation showed significantly higher relative abundance in non-legume Cryptocarya plants than in legume Ormosia plants. The results of non-metric multidimensional scaling analysis showed that bacterial metabolic functional groups were mainly influenced by specific leaf area and leaf phosphorus content.
Conclusion: The higher relative abundance of carbon and nitrogen metabolism functional groups in endophytic bacterial communities of non-legume plants in the Jianfengling tropical mountain rainforest may be one of their adaptive mechanisms to low effective nutrient soil environments.

Aims: Biological soil crusts (BSCs) have important ecological function in arid and semiarid lands. Bacterial community is key to BSCs by playing critical roles in BSCs formation, nutrient cycles and regulatory process. However, bacterial community diversity in BSCs succession and the key environmental factors in Mu Us sandy land remains unclear.
Methods: This study selected bare soil, algal crusts, lichen crusts and moss crusts in Mu Us sandy land as objects. Bacterial abundance and community diversity were investigated by qPCR and Miseq sequencing techniques. The relationship between bacterial community diversity and key environmental factors was explored.
Result: The results indicated that 16S rRNA gene abundance significantly increased with BSCs succession. The index of Chao 1, Shannon diversity and phylogenetic diversity of bacterial community decreased from bare soil to algal crusts and then increased from algal crusts to lichen crusts and moss crusts. There were significant differences in the relative abundance of bacterial phylum, order and genus among different BSCs stages. In bare soil, bacterial communities were dominated by Chitinophagales (Bacteroidota), Tubrobacterales (Actonobacteriota) and Rhizobiales (Proteobacteria). Oscillatoriales (Cyanobacteria) was dominant in algal and lichen crusts, and Chitinophagales (Bacteroidota) and Rhizobiales (Proteobacteria) were dominant members in moss crusts. Total phosphorous, total nitrogen, pH and total organic carbon were key environmental factors in shaping soil bacterial communities.
Conclusion: BSCs succession provides different niches for bacterial communities by changing soil physicochemical characteristics. Soil nutrients (total phosphorous, total nitrogen and soil total organic carbon) and pH play critical roles in screening bacterial species and shaping bacterial community of BSCs in the Mu Us sandy land.

Aims: Protists play an important role in nutrient cycling, microbiome stability and soil fertility maintenance. Compared with bacteria and fungi, the change characteristics and driving factors of soil protist community composition and diversity in degraded grassland ecosystems remain unclear. The aim of this study was to explore the community dynamics of soil protists during the degradation of subalpine meadow in Mount Wutai and its driving factors, and to provide basic data and decision-making references for further research on subalpine meadow ecosystem health monitoring and ecological restoration.
Methods: In this study, high-throughput sequencing technology was used to study the change characteristics and environmental driving factors of soil protist community composition and diversity in subalpine meadow of Mount Wutai under nondegraded (ND), lightly, moderately and heavily degraded (LD, MD and HD) conditions. The α diversity of community was analyzed by Shannon-Wiener index and richness index. Non-metric multidimensional scaling analysis (NMDS) based on Bray-Curtis distance was used to assess the overall structural changes of the protist community. Linear discriminant analysis (LDA) combined with LEfSe analysis was used to determine the biomarkers of statistical difference among four different degradation stage of subalpine meadows. The relationship between protist community structure and environmental variables were analyzed by redundancy analysis (RDA). Variance partitioning analysis (VPA) quantified the effects of soil physicochemical properties and plant variables on the changes of protist community structure.
Results: The results showed that the dominant phyla (relative abundance > 1%) of soil protist in subalpine meadows were Cercozoa, Ochrophyta, Ciliophora, Lobosa, Conosa, Chlorophyta and Apicomplexa. There were significant differences in the relative abundances of Ciliophora, Lobosa, Chlorophyta, Choanoflagellida and Perkinsea among the four different degradation stage of subalpine meadows (P < 0.05). LEfSe showed that the ND meadow was mainly enriched with the phylum Perkinsea group, the LD meadow was enriched with the order Scuticociliatida group, the MD meadow was enriched with the Tubulinea and Oomycota groups, and the HD meadow was mainly enriched with the phototrophs, the Chlorophyta and Bacillariophyta groups. The α diversity of soil protists decreased with the deterioration of subalpine meadow (P < 0.05). NMDS results indicated that there were significant differences in the community structure of soil protists in four degradation stages of subalpine meadow (P < 0.05). Total nitrogen, plant Shannon-Wiener index, aboveground biomass, soil water content and ammonium nitrogen were identified as the top predictors for the composition of protist communities (P < 0.05). VPA showed that both physicochemical factors and vegetation parameters jointly accounted for 38.44% of the variation of the protist community, and soil physicochemical factors (20.69%) had a greater explanation than vegetation parameters (7.85%).
Conclusion: The diversity and community structure of soil protists have changed obviously in the process of subalpine meadow degradation in Mount Wutai. Soil environmental factors are important factors affecting the changes of the protist community structure. The results of this study strengthen the potential of protists as indicators of grassland degradation and provide experimental data for scientific and comprehensive evaluation of soil ecosystem health in subalpine meadow.

Aims: Juglans regia, common walnut or Persia walnut, is an economically important tree crop, which is widely cultivated in northern China. Yet, the genetic diversity and population structure of J. regia in northern China is still under explored. In this study, we carried out population genetic analysis of J. regia in northern China to provide a scientific basis for germplasm conservation and utilization.
Methods: We sampled 491 individuals from 19 populations of J. regia from six provinces in northern China. A total of 31 polymorphic SSR loci were applied to genotype the samples. Different parameters (e.g., N_A, number of alleles; N_E, effective number of alleles; H_O, observed heterozygosity; H_E, expected heterozygosity; A_R, allelic richness; PIC, polymorphism information content) were calculated to characterize the genetic diversity, while genetic differentiation and population structure were assessed using analysis of molecular variance (AMOVA), STRUCTURE, principal coordinates analysis (PCoA) and neighbor-joining tree (NJ) analysis.
Results: The average genetic diversity parameters for the entire dataset were low (N_A = 2.620, H_O = 0.368, H_E = 0.368). AMOVA analysis showed that 16% of the genetic variation was partitioned among populations, and 84% within populations. The clustering results of STRUCTURE, PCoA and NJ revealed two groups in northern China, termed Group 1 and Group 2, respectively. Group 2 included one population from Qinghai Province, with the remaining 18 populations belonging to Group 1. The genetic variation was mainly from within groups, and with a high level of genetic differentiation between groups (F_ST = 0.32). However, the two groups shared a considerable proportion of alleles at contact region, and indeed, a genetic introgression signal was detected there.
Conclusion: We revealed two genetic groups with low genetic diversity of J. regia in northern China. The low genetic diversity of the J. regia populations may be ascribed to the cultivation history and long human-mediated selection and seed dispersal. Genetic differentiation between the two groups may be attributed to cultivation history and local adaptation in contrasting environments. Finally, based on the genetic diversity and genetic structure, we recommend that conservation priority should be given to populations in the Hainan Prefecture of Qinghai Province and Tianshui City of Gansu Province. Our study clarify the genetic diversity and population structure of J. regia from six provinces in Northern China, hence provides a basis for future conservation and utilization of walnut germplasm.

Background: As per the regulations stipulate in the Wildlife Protection Law of the People’s Republic of China, the competent department of the State Council responsible for wildlife protection is mandated to conduct regular scientific evaluations of the List of State Key Protected Wild Animals every five years. The scientific evaluation results, even timely results to the intense needs of specific wildlife protection, should submit to the State Council for promulgation and implementation. The process of updating the list serves as a vital component of China’s comprehensive approach to the wildlife conservation, and allowing for the adaptation to changing circumstances and emerging conservation requirements. It is necessary to establish a set of rational and efficient evaluation methods.
Aim: The objective of this study is to develop and implement efficient and accurate methods for the selection of species to be included or excluded in the list adjustment process.
Methods: By utilizing open data on terrestrial vertebrates list in China and consulting established lists compiled and published by specialized corresponding organizations or institutions (e.g., Global and National Red List, CITES, CMS), six key criteria and eight indicators were carefully selected and assigned weights to construct the adjusted List of State Key Protected Wild Animals. To illustrate the methodology, a case study was conducted to evaluate the suitability of certain species in the list.
Results: The resultant case list obtained through this methodology consists of a total of 922 species, with 204 species categorized as Class I and 718 species as Class II, as potential state key protected wild animals. It is noteworthy that a remarkable level of concordance was observed between the Case List and the latest 2021 List of State Key Protected Wild Animals in China, with 92.0% of the species listed in the former coinciding with those present in the latter, demonstrating a significant degree of consistency between the two lists. By eliminating 8.0% of the species from the 2021 List and incorporating 7.6% of additional species into the case list, noteworthy increases have been observed in the protection ratio of threatened species listed on China’s Red List and IUCN Global Red List, as well as the endemic species of China (6.5%, 5.2% and 5.6%, respectively). Furthermore, adjustments have also been proposed for the protection classification of certain species, particularly those with transboundary distribution, in the Case List. The results are consistent with the principles of identifying and prioritizing endangered, significant, and representative species for conservation purposes.
Perspective: The approach relies on gathering essential data from publicly accessible big data sources, initiates a shift from qualitative assessment to quantitative assessment as the initial stage. The obtained outcomes can form the basis for the expert panel’s qualitative assessment as the second step, thereby enhancing the objectivity and accuracy of the evaluation results and ensuring a balanced representation of diverse animal groups. Notably, the method is characterized by its user-friendly nature and efficient measurement process. Consequently, it can be readily utilized as a reference for other biological groups.

Flower-visiting and pollinating insects play vital roles in maintaining ecosystem functions, but the biodiversity data of these insect groups has been grossly inadequate in China. As a species identification method based on specific gene sequences, DNA barcoding has important application value in specimen identification, discovery of new species, biodiversity conservation, population genetics and evolutionary research. In this study, a total of 815 mitochondrial COI barcodes of flower-visiting insects from Diptera, Lepidoptera and Coleoptera in Daiyun Mountain National Nature Reserve were sequenced and analyzed. The distributions of the insect samples at different elevation were also provided in detail. This dataset can help in constructing regional insect DNA barcode databases, discovering cryptic species, studying altitudinal genetic diversity and biodiversity conservation.

Background & Aims: At the landscape scale, multiple local communities are distributed along environmental gradients, and these local communities are interconnected through species dispersal, together forming metacommunity. When considering both the species composition and interspecific interactions of metacommunity, the concept of metanetwork emerges. With methods in network analysis, metanetwork illustrate the distribution of species interactions across multiple communities. The research scale and numerous network metrics corresponding to different data types often confuse researchers.
Progress: We begin by categorizing and organizing network metrics, and then proceed to differentiate between global and local network metrics. This provides explanations for their application scenarios, computation processes, and ecological significance, while also discussing the impact of sampling intensity on these metrics and exploring their relationships. We introduce the network β-diversity metrics that are computed based on interaction diversity. Subsequently, we outline the statistical inference approaches used in network analysis, incorporating both individual network metrics and network β-diversity metrics. Finally, we provide a summary of the recent research trends, which has shifted from metacommunity to metanetwork.
Prospects: We stress the significance of taking into account the influence of phylogenetic relationships on network composition and interactions in research papers. Multilayer networks offer the capability to represent community structures at a wider scale of species interactions, thus revealing more comprehensive community dynamics. Consistency in the analytical approach of metanetworks is vital for facilitating comparisons across diverse studies.

Background & Aim: As a significant nitrogen source in many natural terrestrial ecosystems where nitrogen is limited, associations formed by bryophytes and nitrogen-fixing cyanobacteria play an essential role in the global nitrogen cycle. Species composition and habitat of bryophyte-cyanobacteria associations result in contrasting nitrogen fixation capacities in different ecosystems. However, the current studies on bryophyte-cyanobacteria associations are predominately conducted in high-latitude ecosystems of the Northern Hemisphere, with few and scattered reports in other ecosystems. Therefore, we summarized the distribution, species composition, cyanobacterial colonization rate, cyanobacterial abundance, and nitrogen fixation potential of reported bryophyte-cyanobacteria associations worldwide, aiming to provide a reference for further study on the diversity and nitrogen fixation capacity of bryophyte- cyanobacteria associations in various ecosystems globally.
Progress: According to our analysis and summarization, a total of 110 bryophyte species from 58 genera in 41 families and more than 26 cyanobacteria species from 17 genera in 9 families, were identified to be involved in bryophyte-cyanobacteria symbiotic associations. The associated bryophyte species varied among diverse ecosystems. For example, Pleurozium schreberi-cyanobacteria associations are dominate in the understory of boreal forests, while Sphagnum spp.-cyanobacteria associations dominate wetland ecosystems. Nostoc species are the dominant cyanobacteria in most ecosystems due to their unique physiological characteristics and strong ecological adaptability. Among different ecosystems the colonization rate, abundance, and nitrogen fixation capacity of cyanobacteria on bryophytes differed significantly. Nitrogen fixation was highest in Arctic tundra ecosystems (1.3-24.6 kg N·ha^-1·yr^-1), followed by boreal forests (0.04-11.53 kg N·ha^-1·yr^-1), and was the lowest in temperate grasslands (0.008-0.124 kg N·ha^-1·yr^-1).
Perspective: We emphasized that the research on species composition and the capacity for nitrogen fixation was quite inadequate. We also highlighted four research perspectives: (1) Employing techniques such as metagenomics and establishing observation and research stations to explore and study the colonization characteristics and nitrogen fixation ability of cyanobacteria associated with bryophytes. (2) Conducting further and systematic research on bryophyte-cyanobacteria associations in all types of ecosystems. (3) Unifying the measurement and estimation methods of nitrogen fixation rate in different ecosystems. (4) Determining the key influencing factors and regulatory pathways of the diversity, distribution, colonization rate, cyanobacteria abundance, and nitrogen fixation rate of bryophyte- cyanobacteria associations.

Aims: Urban biodiversity conservation is a vital component of the global conservation system and an essential element for sustainable urban development. Comparing the practices of urban biodiversity conservation in China and Europe is helpful to improve the measures of urban biodiversity conservation in China. This paper conducts a comparative analysis of urban biodiversity conservation practices in China and Europe, aiming to offer insights for enhancing urban ecosystems and biodiversity conservation..
Methods: We propose a theoretical framework for urban biodiversity conservation from the perspective of urban development and collaborative governance of ecosystems. The framework is based on the core carriers and functions of urban biodiversity conservation, and it emphasizes the implementation strategies for habitat conservation, spatial regulation, and collaborative governance.
Results and Suggestions: China’s urban biodiversity conservation exhibits unique concepts and significant governance effects, however, there is still room for improvement. (1) Regarding urban development planning, the European urban biodiversity planning system is comprehensive, systematic, and targeted. In contrast, the integration of urban biodiversity conservation and urban development planning in China is inadequate. Thus, it is recommended to enhance the effective connection between these two aspects. (2) Regarding urban green space construction, European cities are increasingly emphasizing the connectivity and integrity of ecosystems. In contrast, Chinese cities primarily concentrate on building traditional green spaces like parks and should enhance the utilization of green space and promote ecosystem creation at the microscopic scale. (3) Regarding ecological protection compensation, European cities have made significant progress in diversified and market-based compensation. However, China’s urban biodiversity protection compensation mechanism is not yet fully developed and requires gradual exploration of diversified compensation methods, such as the implementation of green funds. (4) Regarding public participation, European cities prioritize bottom-up mechanisms for biodiversity conservation, whereas China primarily relies on government-led governance, indicating the need for enhancing public awareness and participation capabilities.

Background & Aims: After the Conference of the Parties to the Convention on Biological Diversity (CBD), the Kunming-Montreal Global Biodiversity Framework (GBF) was implemented to address global biodiversity priorities. This paper brings in a holistic, systematic thinking path based on the SFIC model to research the challenges faced in the implementation of the Kunming-Montreal GBF, and puts forward corresponding policy priorities that offer suggestions to policy-makers on implementation.
Methods: This paper identifies documents related to Kunming-Montreal GBF, Aichi Targets, CBD, United Nations Environment Programme (UNEP), as well as global biodiversity governance and analyzes their contents.
Results: Our results indicate that the implementation of Kunming-Montreal GBF needs global collaborative cooperation instead of acting separately and identifies a lack of holistic analysis in current research efforts. We then combine elements in the SFIC model with data on biodiversity governance, and analyze the implementation challenges. These challenges include basic differences between developing and developed countries, cooperating relationships, acting motivations, information communication, trust construction, funds collection, following Kunming-Montreal GBF details, system design, and leadership from the UN branch and major countries.
Conclusion: On analyzing the challenges and the SFIC model structure, we present several policy suggestions, including promoting resource mobilization and capacity building in developing countries, facilitating trilateral assistance and cooperation, strengthening information communication and sharing, consolidating trust construction, accumulating funds, fostering further negotiation, seeking the balance between the constraining force and encouragement of the system, improving the fairness and rationality of the system, strengthening the leadership of UN branch in charge and major countries.

Background & Aims: Biodiversity conservation has both scientific and ethical attributes, and it is faced with two basic questions: first, what do we want to conserve, and second, what should we prioritize for conservation? Genes, species, ecosystems and other levels are important targets for biodiversity conservation, and among them, the conservation of species is the most crucial. Species diversity is linked to genetic diversity and ecosystem diversity, which is the foundation of all biodiversity conservation. However, the concept of species and the relationship between species and individuals are still controversial, yet declining biodiversity situation requires urgent action. Therefore, our goal is to define an operational species concept for conservation, rather than a standardized and universal species definition, in order to mitigate the dilemmas that species definition and species delimitation have brought to conservation work.
Perspectives & Conclusion: All species are undergoing speciation and the degree and timing of speciation varies widely. These processes make it impossible to develop uniform criteria for species classification, thus making species and individuals inappropriate targets for biodiversity conservation; the target should instead be “species diversity”. Starting from the goal of diversity, the species that are the objects of conservation must be independently evolving units, with both morphological distinctions and genetic differences. Only when the two basic requirements of morphological differences and genetic differences are met simultaneously can the essential goal of diversity be realized. This delineation also allows for the existence of hybrids or back-cross individuals that do not belong to the two species groups. At the same time, as a conservation target, there must be an operable and relatively reasonable method to define species, and integrated taxonomy may be an attractive path. Biological taxonomists should, on the basis of traditional classification theories and methods, comprehensively utilize multidisciplinary knowledge such as morphology, genetics, cytology, ecology, molecular biology and other cutting-edge technologies like DNA barcoding, artificial intelligence image recognition, and modern machine learning, to provide more evidence for the definition and delimitation of species. In so doing, this will allow for the identification of the most solid basic knowledge to support biodiversity conservation.