Conservationists have long debated whether fragmented habitats are best conserved by protecting a single large patch(SL)or several small patches(SS),i.e.,the SLOSS debate.Although this SLOSS debate has provided import...Conservationists have long debated whether fragmented habitats are best conserved by protecting a single large patch(SL)or several small patches(SS),i.e.,the SLOSS debate.Although this SLOSS debate has provided important insights into biodiversity conservation,research has predominantly focused on only one dimension of diversity(i.e.,taxonomic),failing to consider how phylogenetic and functional diversity might inform conservation strategies.In this study,we determined whether grasslands in the agro-pastoral ecotone of the Tabu River Basin,Inner Mongolia should be conserved by protecting a single large patch or several small patches.For this purpose,we quantified the relationships between three dimensions of biodiversity(taxonomic,phylogenetic,and functional diversity)and grassland patch area.We found species richness and the standardized effect size of phylogenetic diversity increased with patch area,whereas the standardized effect size of functional diversity decreased.Taxonomic measures of diversity indicated that the best strategy for conserving Tabu River Basin grasslands is to protect several small habitat patches;in contrast,phylogenetic and functional measures of diversity indicated that conserving a single large habitat patch was best.Our study emphasizes the necessity of considering multiple dimensions of diversity when designing conservation strategies for fragmented landscapes to achieve comprehensive biodiversity conservation.展开更多
Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the She...Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the Shettihalli tropical forest landscape of the Western Ghats biodiversity hotspot,India,to analyse tree community composition and the drivers ofα-diversity(Shannon)andβ-diversity(LCBD).Compositional patterns were visualized using Non-Metric Multidimensional Scaling(NMDS),and hybrid feature selection with structural equation modeling(SEM)was employed to evaluate the direct and indirect effects of environmental variables on diversity.NMDS identified four distinct forest types in the Shettihalli landscape:semi-evergreen,dry deciduous,moist deciduous,and plantation forests,each with distinct plant composition.Shannon diversity and ecological uniqueness was significantly higher in semi-evergreen forest than in deciduous forest plots.The SEMs explained about 79%and 39–45%of the variation inα-diversity andβ-diversity.Our analysis indicated that current diversity patterns result from multiple processes,with structure,disturbance,and edaphic parameters exerting the strongest direct and indirect effects onα-diversity.β-diversity,in contrast,was largely influenced by climate,topography,stand structure,and edaphic factors.Overall,our findings indicate that various factors(e.g.,climate,topography,and human disturbance)interact to shape tree diversity patterns in tropical forests.These findings will help develop unique conservation and management strategies for distinct forest types in tropical forest ecosystems.展开更多
In this paper,we propose a random access scheme termed sign-compute diversity slotted ALOHA(SCDSA).The SCDSA scheme combines diversity transmission with compute-and-forward.Without considering the capture effect and m...In this paper,we propose a random access scheme termed sign-compute diversity slotted ALOHA(SCDSA).The SCDSA scheme combines diversity transmission with compute-and-forward.Without considering the capture effect and multiple user detection techniques,our scheme can reach a high throughput of 0.98 without feedback under finite frame size settings,where the upper bound on performance is 1.Moreover,a lower bound on throughput performance is derived,which is tight in some parameter settings and can be used to approximate theoretical performance.Simulation results validate our analysis and confirm the advantages of our proposed scheme.展开更多
One of the research hotspots in geotechnical engineering is the solidification of problematic soil foundations. However, the traditional materials, such as Portland cement, lime, and various types of chemical solution...One of the research hotspots in geotechnical engineering is the solidification of problematic soil foundations. However, the traditional materials, such as Portland cement, lime, and various types of chemical solutions, typically cause CO_(2) emissions and environmental pollution. Geopolymer is a newly proposed method for soil solidification, offering an environmentally friendly and effective solution. Given that soils typically consist of diverse compositions, an optimal soil stabilization technique should be versatile enough to be applied across various soil types, ensuring consistent strength outcomes with minimal variations among different soil compositions. In this study, three commonly used geopolymers(fly ash, ground granulated blast-furnace slag, and metakaolin) were utilized to stabilize silt, loess, silica sand, calcareous sand, and gravel, representing a diverse range of soils. The mechanical properties and microstructures of both geopolymers and geopolymerstabilized soils were analyzed. The findings indicated that the strength of stabilized coarse cohesionless soils was primarily influenced by the mechanical properties of the geopolymers themselves, with minimal impact from the inherent properties of the soil. However, the effectiveness of stabilizing cohesive soil may show significant discrepancies compared to the mechanical properties of geopolymer materials when certain types of geopolymers, like metakaolin, are employed. Higher strength is typically achieved through a denser structure(with fewer pores) and the presence of products with a higher degree of polymerization. Additionally, ground granulated blast-furnace slag exhibited excellent stability and superior strength when compared to other types of geopolymers. The present research establishes a basis for selecting geopolymers to stabilize a range of soils, including those with non-uniform compositions and diverse components.展开更多
Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges...Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges.There has been a lack of a comprehensive and multidimensional assessment to inform strategic conservation planning.Therefore,this study integrated 4 key biodiversity indices including species richness(SR),phylogenetic diversity(PD),threatened species richness(TSR),and endemic species richness(ESR)to map species diversity distribution patterns,identify conservation gaps,and elucidate their effects of climatic factors.This study revealed that species diversity shows a clear trend of decreasing from the western region to the eastern region of Tajikistan.The central–western mountains(specifically the Gissar-Darvasian and Zeravshanian regions)emerge as irreplaceable biodiversity hotspots.However,we found a severe spatial mismatch between these priority areas and the existing protected areas(PAs).Protection coverage for all hotspots was alarmingly low,ranging from 31.00%to 38.00%.Consequently,a critical 64.80%of integrated priority areas fall outside of the current PAs,representing a major conservation gap.This study identified precipitation seasonality and isothermality as the principal drivers,collectively explaining over 50.00%of the diversity variation and suggesting high vulnerability to hydrological shifts.Furthermore,we detected significant geographic sampling bias in the public biodiversity databases,with the most critical hotspot being systematically under-sampled.This study provides a robust scientific basis for conservation action,highlighting the urgent need to strategically expand PAs in the under-protected southwestern region and to mitigate critical sampling gaps through targeted data digitization and field surveys.These measures are indispensable for securing Tajikistan’s unique biodiversity and achieving the Kunming-Montreal Global Biodiversity Framework Target 3(“30×30 Protection”).展开更多
The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The mai...The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The main distribution area of the C. angulata is located in Fujian, South China. In total, 420 C. angulata were collected from 14 natural habitats(populations) along the Fujian coast, and their genetic diversity and structure were analyzed in the mitochondrial COI and nuclear gene ITS2 sequences. Results reveal that all the 14 populations of C. angulata exhibited high levels of genetic diversity, with a total of 57(haplotype diversity: 0.811±0.016) and 124(haplotype diversity: 0.912±0.007) haplotypes revealed by COI and ITS2, respectively. Notably, significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ) population(FS T by COI: 0.035–0.142, P<0.05;FS T by ITS2: 0.078–0.123, P<0.05) with other populations were observed for the first time, which is also supported by the results of molecular variance analysis(FC T by COI: 0.105, P<0.05;FC T by ITS2: 0.086, P<0.05) and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree. Furthermore, the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations. In addition, the population dynamics analysis suggests that the C. angulata may have undergone expansion during the third ice age of the Pleistocene. These results provide a reference for the preservation and further genetic improvement of C. angulata.展开更多
The latitudinal diversity gradient(LDG)is one of the most notable biodiversity patterns in biogeography.The metabolic theory of ecology(MTE)explains ecological patterns,including the LDG.However,little is known about ...The latitudinal diversity gradient(LDG)is one of the most notable biodiversity patterns in biogeography.The metabolic theory of ecology(MTE)explains ecological patterns,including the LDG.However,little is known about whether the LDG remains stable over time as climate warming progresses and whether MTE remains applicable to clarify this pattern.In this study,forest data spanning temperate,subtropical,and tropical zones across China were used to analyze long-term changes in the LDG of tree species over 2005-2020.Based on the MTE framework,spatial scales were considered to assess temperature dependence of typical forest trees species.Our results show that species richness decreased with increasing latitude,and that temperature was the primary driver of this change.Although temperature in China has significantly increased over the past two decades,the LDG of tree species has remained stable.However,there was a decrease in species richness in tropical regions over time.With predictions of the MTE,the logarithm of typical forest tree species richness exhibited negative linear relationships with the inverse of ambient temperature,indicating temperature dependence of species richness.However,the relationship remained stable and was strongly influenced by spatial scale,intensifying as spatial scale increased.The findings emphasize the important role of temperature in shaping the LDG.The effects of spatial scale,in particular,should be considered when biodiversity management plans are developed for future climate change.展开更多
Mountains serve as exceptional natural laboratories for studying biodiversity due to their heterogeneous landforms and climatic zones.The Himalaya,a global biodiversity hotspot,hosts rich endemic flora,supports vital ...Mountains serve as exceptional natural laboratories for studying biodiversity due to their heterogeneous landforms and climatic zones.The Himalaya,a global biodiversity hotspot,hosts rich endemic flora,supports vital ecosystem functions,and offers a unique window into multifaceted plant diversity patterns.This review synthesizes research on Himalayan plant diversity,including species,phylogenetic,functional,and genetic dimensions,highlighting knowledge gaps and solutions.Research on Himalayan plant diversity has developed significantly.However,gaps remain,especially in studies on phylogenetic and functional diversity.The region's vegetation ranges from tropical rainforests to alpine ecosystems,with species richness typically following a hump-shaped distribution along elevation gradients.The eastern Himalaya exhibits higher plant diversity than the central and western regions.Low-elevation communities were found to be more functionally diverse,whereas high-elevation communities displayed greater ecological specialization.Communities at mid-elevations tend to show greater phylogenetic diversity than those at higher and lower elevations.The eastern and western flanks of the Himalaya retain high levels of genetic diversity and serve as glacial refugia,whereas the central region acts as a hybrid zone for closely related species.Himalayan plant diversity is shaped by historical,climatic,ecological and anthropogenic factors across space and time.However,this rich biodiversity is increasingly threatened by environmental change and growing anthropogenic pressures.Unfortunately,research efforts are constrained by spatial biases and the lack of transnational initiatives and collaborative studies,which could significantly benefit from interdisciplinary approaches,and other coordinated actions.These efforts are vital to safeguarding the Himalayan natural heritage.展开更多
Understanding the genetic diversity–area relationship(GAR)is essential for comprehending how species adapt to environmental changes,as genetic diversity is an indicator of a species’adaptive potential.Variation in e...Understanding the genetic diversity–area relationship(GAR)is essential for comprehending how species adapt to environmental changes,as genetic diversity is an indicator of a species’adaptive potential.Variation in environmental adaptation capacity exists among species and animal taxa with different distribution areas,highlighting the importance of understanding the GAR.To obtain a more comprehensive understanding of the GAR in terrestrial vertebrates,we assessed both haplotype diversity–area and nucleotide diversity–area relationships using 25,453 cytochrome c oxidase subunit I(COI)sequences from 142 amphibian species,574 bird species,and 342 mammal species.We found that both measures of genetic diversity increased with species range size across major animal groups.Nevertheless,the GAR did not differ among animal groups,while haplotype diversity performed better than nucleotide diversity in profiling the GAR,as indicated by higher R2 values.The difference in the modeling fit may stem from the distinct biological and mathematical significance of nucleotide diversity and haplotype diversity.These results suggest that the GAR follows similar rules among different animal taxa.Furthermore,haplotype diversity may serve as a more reliable indicator for assessing the potential effects of area size changes on animal populations and provide better guidance for conserving genetic diversity.展开更多
Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental condit...Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental conditions that facilitate the persistence of species during environmental changes and exhibit unique ecoevolutionary dynamics.However,our knowledge about how topographic complexity and related ecoevolutionary selective forces influence the functional and phylogenetic signatures of species assemblages in microrefugia is very limited.Although the conceptual framework on the systematic integration of plant functional traits into the study of refugia is well established,more empirical studies on functional trait composition and functional diversity in refugia are urgently needed for more effective conservation.Here we analyzed the distribution of various plant functional traits and phylogenetic patterns in microhabitats(south-and north-facing slopes,and bottoms)of 30 large topographic depressions(i.e.doline microrefugia)and microhabitats of the surrounding plateaus in two distant forested karst regions.We found that plant assemblages in the understory of dolines and their surroundings are characterized by unique functional values and combinations of traits.Doline bottoms had the highest functional diversity among doline microhabitats and supported plant assemblages with considerably different trait compositions from the plateaus.Bottoms also had the highest phylogenetic diversity.These results suggest that topographic complexity in forested dolines has a significant effect on the distribution of plant functional traits in the understory.High functional and phylogenetic diversity in doline bottoms can have important consequences for the long-term survival of plant populations,highlighting that these microhabitats may provide a higher resilience and support an adaptive community-level response to natural and anthropogenic stressors.Understanding mechanisms that drive the survival of species within microrefugia is required to determine the best conservation and management strategies.展开更多
The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic ...The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic diversity,with relatively less research on functional and phylogenetic diversity.In this study,we examined the phylogenetic and functional diversity and underlying influencing factors of bird communities in 37 urban parks in Nanjing,China.We conducted a systematic survey of bird communities in Nanjing urban parks and selected six park characteristics that are generally considered to affect bird diversity.Model selection based on corrected Akaike Information Criterion(AICc)and model averaging showed that park area,habitat diversity and building index(a proxy for the degree of urbanization)were significant factors affecting avian phylogenetic and functional diversity in Nanjing urban parks.Specifically,habitat diversity and park area were positively correlated with bird diversity,while the building index was negatively correlated with bird diversity.Moreover,the phylogenetic and functional structures of urban bird communities exhibited a clustered pattern,indicating that environmental filtering might play a role in shaping community composition.In addition,building index had certain impact on the construction of bird phylogenetic communities in urban parks.Our results suggest that expanding park areas,increasing habitat diversity and reducing building indexes may be effective measures to increase the avian phylogenetic and functional diversity in our system.展开更多
Urban wetlands are considered as"habitat islands"within the urban matrix that contribute to species conservation.Waterbirds are sensitive pollution indicators in terrestrial and aquatic ecosystems,and their ...Urban wetlands are considered as"habitat islands"within the urban matrix that contribute to species conservation.Waterbirds are sensitive pollution indicators in terrestrial and aquatic ecosystems,and their diversity in urban wetlands reflects the response of wildlife to urbanization.However,very few studies have investigated seasonal differences in the multidimensional diversity of waterbirds in urbanized landscapes.In this study,we analyzed various wetland parameters that could potentially affect the seasonal variations in multidimensional diversity of waterbirds in Nanjing,China.We surveyed waterbirds in 29 urban wetlands using the point count method during breeding and non-breeding seasons from November 2022 to June 2023.We then employed multiple linear regressions and information-theoretic approaches to investigate the impact of wetland characteristics on waterbird diversity.We found that water body area and buffer zone connectivity consistently emerged as positive factors affecting waterbird taxonomic and phylogenetic diversity across seasons.Conversely,the urbanization synthetic index was negatively correlated with waterbird diversity only during the breeding season.Regarding functional diversity,we found that the positive correlation between buffer zone connectivity and waterbird diversity was specific to the breeding season.Therefore,for effective conservation of waterbird diversity in our system,wetland planning should prioritize expanding wetland water body areas,enhancing wetland connectivity,minimizing human disturbance during the breeding season,and implementing ecological restoration measures in urbanized wetlands to mitigate adverse effects of urbanization.展开更多
Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored varia...Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored variations in composition, diversity, cover,and life forms of vascular plants along a complete altitudinal gradient(1300-4000 m a.s.l) in Sierra de Velasco, an arid mountain in northwestern Argentina.We evaluated the influence of environmental variables on plant diversity and cover. Field sampling was conducted in the northern sector of the Sa. de Velasco,on the western slope in eight 50 m wide altitudinal bands at 400 m elevation intervals. We used rectangular plots(20 × 4 m;n:10/altitudinal band) to register the vascular plants of all the growth forms, and linear transects(20 m long.;n:30/altitudinal band) to quantify the vegetation cover using the point intercept method. Diversity was calculated using hill numbers.Data analysis included non-metric multidimensional scaling(NMDS), indicator species analysis,generalized linear models(GLMs), and variance partitioning analysis. A total of 232 species from 51families and 158 genera were registered. Species composition showed greater similarity at intermediate elevations. Plant diversity and cover exhibited a unimodal distribution, peaking at intermediate elevations(2100-2500 m). In contrast, life forms' distribution showed divergent patterns. Therophytes and succulents predominated at low altitudes,phanerophytes and hemicryptophytes at medium altitudes, and chamaephytes and geophytes at high altitudes. The altitudinal patterns of plant diversity and cover were primarily driven by climatic factors.Conservation efforts in the Sierra de Velasco should focus on the middle and upper zones due to their high biodiversity and vulnerability to climate change.展开更多
Red anaerobic ammonia oxidation (Anammox) granular sludge (AnGS) has been reported insuccessfully operating Anammox systems, and its color is associated with sludge activity.However, in long-term operating systems, An...Red anaerobic ammonia oxidation (Anammox) granular sludge (AnGS) has been reported insuccessfully operating Anammox systems, and its color is associated with sludge activity.However, in long-term operating systems, AnGS exhibits different sensory colors, physicalstructures, community structures, and denitrification performance, but the relationship betweenthem has not yet been elucidated.The AnGS of the Anammox system, which has beenin operation for more than a decade, can be divided into twomain categories: red and white.The specific Anammox activity (SAA) in conventional red AnGS increased continuously asthe particle size increased from <0.51 mm to 6.02 ± 0.84 mm. The SAA of white AnGS wereslightly lower than those of red AnGS with similarly-size granules but significantly higherthan AnGS with smaller red granules. Compared with red AnGS, the extracellular polymericsubstances of white AnGS were significantly reduced,mainly due to the higher intracellulariron content, resulting in lower heme c concentration. Thus, heme c may prove not to bean evaluative tool for measuring Anammox activity. Red and white AnGS, whether throughself-aggregation or adsorption by hydroxyl apatite and other carriers, will face the fate ofinternal voids during particle size growth. White AnGS exhibited amore complex microbialcommunity than red AnGS. Candidatus Brocadia was abundant in red AnGS and the abundanceincreased with increasing granule size. Candidatus Kuenenia and Candidatus Jetteniamade significant contributions to denitrification in white AnGS. This study provides a newperspective on particle selection for anammox engineering applications.展开更多
Understanding how and why assemblage dissimilarity changes along spatial gradient is a great challenge in ecology,because answers to these questions depend on the analytical types,dimensions,and components of beta div...Understanding how and why assemblage dissimilarity changes along spatial gradient is a great challenge in ecology,because answers to these questions depend on the analytical types,dimensions,and components of beta diversity we concerned.To obtain a comprehensive understanding of assemblage dissimilarity and its implications for biodiversity conservation in the Himalayas,we explored the elevational patterns and determinants of beta diversity and its turnover and nestedness components of pairwise and multiple types and taxonomic and phylogenetic dimensions simultaneously.Patterns of beta diversity and their components of different types and dimensions were calculated based on 96 sampling quadrats along an 1800-5400 m elevational gradient.We examined whether and how these patterns differed from random expectations using null models.Furthermore,we used random forest methods to quantify the role of environmental variables representing climate,topography,and human disturbance in determining these patterns.We found that beta diversity and its turnover component,regardless of its types and dimensions,shown a hump-shaped elevational patterns.Both pairwise and multiple phylogenetic beta diversity were remarkably lower than their taxonomic counterpart.These patterns were significantly less than random expectation and were mostly associated with climate variables.In summary,our results suggested that assemblage dissimilarity of seed plants was mostly originate from the replacement of closely related species determined by climate-driven environmental filtering.Accordingly,conservation efforts should better cover elevations with different climate types to maximalize biodiversity conservation,rather than only focus on elevations with highest species richness.Our study demonstrated that comparisons of beta diversity of different types,dimensions,and components could be conductive to consensus on the origin and mechanism of assemblage dissimilarity.展开更多
Understanding plant diversity within geographical ranges and identifying key species that drive community variation can provide crucial insights for the management of grasslands.However,the contribution of both local ...Understanding plant diversity within geographical ranges and identifying key species that drive community variation can provide crucial insights for the management of grasslands.However,the contribution of both local sites and plant species to beta diversity in grassland ecosystems has yet to be accurately assessed.This study applied the ecological uniqueness approach to examine both local contributions to beta diversity(LCBD)and species contributions to beta diversity(SCBD)across six major geographical ranges in alpine grasslands.We found that LCBD was driven by species turnover,with climate,plant communities,and their interactions influencing LCBD across spatial scales.LCBD values were high in areas with low evapotranspiration,high rainfall variability,and low species and functional richness.Precipitation seasonality predicted large-scale LCBD dynamics,while plant community abundance explained local LCBD variation.In addition,we found that SCBD were confined to species with moderate occupancy,although these species contributed less to plant biological traits.Our findings are crucial for understanding how ecological characteristics influence plant beta diversity in grasslands and how it responds to environmental and community factors.In addition,these findings have successfully identified key sites and priority plants for conservation,indicating that using standardized quadrats can support the assessment of the ecological uniqueness in grassland ecosystems.We hope these insights will inform the development of conservation strategies,thereby supporting regional plant diversity and resisting vegetation homogenization.展开更多
The authors regret that an error occurred during the preparation of their article:One of the official databases,which was used for functional trait collections,contained an incorrect term–'chametophytes'–for...The authors regret that an error occurred during the preparation of their article:One of the official databases,which was used for functional trait collections,contained an incorrect term–'chametophytes'–for the life form category'chamaephytes'.Unfortunately,this incorrect term was used throughout the article following the nomenclature of this official database:in one instance in the main text,in Fig.3 and its caption,in Fig.5,and in two instances in the supplementary material.展开更多
On the morning of May 31st,the parallel forum"Seeking Harmony without Uniformity in Mutual Learning:Diversity of Civilisations from the Sinologists'Perspective"was held in Dunhuang.The forum was hosted b...On the morning of May 31st,the parallel forum"Seeking Harmony without Uniformity in Mutual Learning:Diversity of Civilisations from the Sinologists'Perspective"was held in Dunhuang.The forum was hosted by the Chinese Association for International Understanding and organised by Beijing Language and Culture University.Leading Sinologists and Chinese culture researchers from Europe,Asia and Latin America gathered to discuss the theme of civilisational diversity and explore pathways for coexistence and mutual enrichment.展开更多
Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental grad...Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental gradients can influence this diversity through mechanisms such as gene flow, selection, and genetic drift. To explore how these forces interact, we assessed neutral and adaptive genetic variation in three widely distributed and two narrowly distributed bird species co-occurring along the Cauca River canyon in Antioquia, Colombia—a region of pronounced environmental heterogeneity. We sampled individuals across eight sites spanning the canyon's gradient and analyzed genetic diversity and structure using microsatellites and toll-like receptors (TLRs), a gene family involved in innate immunity. Widely distributed species consistently exhibited higher genetic diversity at both marker types compared to their narrowly distributed counterparts. Although we did not find a significant relationship between microsatellite heterozygosity and TLR heterozygosity, we evidenced a negative trend for widely distributed species and a positive trend for narrowly distributed species. This result suggests that there is a stronger effect of genetic drift in narrowly distributed species. Our results highlight the role of distribution range in maintaining genetic diversity and suggest that environmental gradients, by interacting with gene flow and selection, may influence patterns of adaptive variation.展开更多
The response of plant functional diversity to external disturbances not only effectively predicts changes in the ecosystem but it also reflects how plant communities use external environmental resources.However,resear...The response of plant functional diversity to external disturbances not only effectively predicts changes in the ecosystem but it also reflects how plant communities use external environmental resources.However,research on how different herbivore assemblages affect plant functional diversity is limited.Therefore,this study systematically explored the effects of three typical herbivore assemblages(yak grazing,Tibetan sheep grazing,and mixed grazing by yaks and Tibetan sheep)on species richness,plant functional diversity,and soil physicochemical properties in alpine grasslands on the Qinghai-Tibet Plateau,China.This study further investigated the primary mechanisms driving the changes in plant functional diversity.The results indicate four key aspects of this system:(1)Grazing significantly enhanced plant functional diversity,particularly when the mixed grazing by yaks and Tibetan sheep was applied at a ratio of 1:2.This ratio showed the most substantial improvement in the functional dispersion index and Rao's quadratic entropy index.(2)Compared to enclosed treatments,grazing increased species richness andβ-diversity,contributing to higher plant functional diversity.(3)Grazing treatments affected various plant traits,such as reducing plant community height and leaf thickness while increasing specific leaf area.However,the impact on plant functional diversity was most pronounced under the mixed grazing by yaks and Tibetan sheep at a ratio of 1:2.(4)Speciesα-diversity was positively correlated with plant functional diversity.Changes in plant functional diversity were primarily regulated by variations in soil physicochemical properties.Specifically,increases in soil available nitrogen significantly promoted changes in plant functional diversity,while increases in soil available potassium and bulk density had a significant inhibitory effect on these changes.Long-term grazing significantly reduced the height of plant communities in alpine meadows,while a balanced mixture of yak and Tibetan sheep grazing,especially at a ratio of 1:2,enhanced plant functional diversity the most.This suggests that,under these conditions,the use of external environmental resources by the plant community is optimized.展开更多
基金supported by the Natural Science Foundation of Inner Mongolia Key Project(2023ZD24)the Erdos City Major Science and Technology Special Project(ZD20232305)+3 种基金the Inner Mongolia Autonomous Region Science and Technology Plan Project(2025KYPT0012)the Inner Mongolia Autonomous Region Science and Technology Plan Project(2022ZD007)the Inner Mongolia Autonomous Region Education Department Project(NMGIRT2409)the Inner Mongolia First-Class Disciplines Scientific Research Special Project(YLXKZX-ND-047).
文摘Conservationists have long debated whether fragmented habitats are best conserved by protecting a single large patch(SL)or several small patches(SS),i.e.,the SLOSS debate.Although this SLOSS debate has provided important insights into biodiversity conservation,research has predominantly focused on only one dimension of diversity(i.e.,taxonomic),failing to consider how phylogenetic and functional diversity might inform conservation strategies.In this study,we determined whether grasslands in the agro-pastoral ecotone of the Tabu River Basin,Inner Mongolia should be conserved by protecting a single large patch or several small patches.For this purpose,we quantified the relationships between three dimensions of biodiversity(taxonomic,phylogenetic,and functional diversity)and grassland patch area.We found species richness and the standardized effect size of phylogenetic diversity increased with patch area,whereas the standardized effect size of functional diversity decreased.Taxonomic measures of diversity indicated that the best strategy for conserving Tabu River Basin grasslands is to protect several small habitat patches;in contrast,phylogenetic and functional measures of diversity indicated that conserving a single large habitat patch was best.Our study emphasizes the necessity of considering multiple dimensions of diversity when designing conservation strategies for fragmented landscapes to achieve comprehensive biodiversity conservation.
基金supported by the Department of Biotechnology,Ministry of Science and Technology,Govt.India,under grant No.BT/Coord.II/10/02/2016/22.03.2018the Indian Council of Social Science Research,New Delhi,India,for providing a short-term doctoral fellowship(RFD/Short-Term/2022-23/ENV/ST/66).
文摘Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the Shettihalli tropical forest landscape of the Western Ghats biodiversity hotspot,India,to analyse tree community composition and the drivers ofα-diversity(Shannon)andβ-diversity(LCBD).Compositional patterns were visualized using Non-Metric Multidimensional Scaling(NMDS),and hybrid feature selection with structural equation modeling(SEM)was employed to evaluate the direct and indirect effects of environmental variables on diversity.NMDS identified four distinct forest types in the Shettihalli landscape:semi-evergreen,dry deciduous,moist deciduous,and plantation forests,each with distinct plant composition.Shannon diversity and ecological uniqueness was significantly higher in semi-evergreen forest than in deciduous forest plots.The SEMs explained about 79%and 39–45%of the variation inα-diversity andβ-diversity.Our analysis indicated that current diversity patterns result from multiple processes,with structure,disturbance,and edaphic parameters exerting the strongest direct and indirect effects onα-diversity.β-diversity,in contrast,was largely influenced by climate,topography,stand structure,and edaphic factors.Overall,our findings indicate that various factors(e.g.,climate,topography,and human disturbance)interact to shape tree diversity patterns in tropical forests.These findings will help develop unique conservation and management strategies for distinct forest types in tropical forest ecosystems.
文摘In this paper,we propose a random access scheme termed sign-compute diversity slotted ALOHA(SCDSA).The SCDSA scheme combines diversity transmission with compute-and-forward.Without considering the capture effect and multiple user detection techniques,our scheme can reach a high throughput of 0.98 without feedback under finite frame size settings,where the upper bound on performance is 1.Moreover,a lower bound on throughput performance is derived,which is tight in some parameter settings and can be used to approximate theoretical performance.Simulation results validate our analysis and confirm the advantages of our proposed scheme.
基金supported by the National Natural Science Foundation of China (Grant No.52308352)the Jiangxi Provincial Natural Science Foundation (Grant Nos.20242BAB25299,20232BAB214082)。
文摘One of the research hotspots in geotechnical engineering is the solidification of problematic soil foundations. However, the traditional materials, such as Portland cement, lime, and various types of chemical solutions, typically cause CO_(2) emissions and environmental pollution. Geopolymer is a newly proposed method for soil solidification, offering an environmentally friendly and effective solution. Given that soils typically consist of diverse compositions, an optimal soil stabilization technique should be versatile enough to be applied across various soil types, ensuring consistent strength outcomes with minimal variations among different soil compositions. In this study, three commonly used geopolymers(fly ash, ground granulated blast-furnace slag, and metakaolin) were utilized to stabilize silt, loess, silica sand, calcareous sand, and gravel, representing a diverse range of soils. The mechanical properties and microstructures of both geopolymers and geopolymerstabilized soils were analyzed. The findings indicated that the strength of stabilized coarse cohesionless soils was primarily influenced by the mechanical properties of the geopolymers themselves, with minimal impact from the inherent properties of the soil. However, the effectiveness of stabilizing cohesive soil may show significant discrepancies compared to the mechanical properties of geopolymer materials when certain types of geopolymers, like metakaolin, are employed. Higher strength is typically achieved through a denser structure(with fewer pores) and the presence of products with a higher degree of polymerization. Additionally, ground granulated blast-furnace slag exhibited excellent stability and superior strength when compared to other types of geopolymers. The present research establishes a basis for selecting geopolymers to stabilize a range of soils, including those with non-uniform compositions and diverse components.
基金the Chinese Academy of Sciences Research Center for Ecology and Environment of Central Asia(RCEECA),the construction and joint research for the China-Tajikistan“Belt and Road”Joint Laboratory on Biodiversity Conservation and Sustainable Use(2024YFE0214200)the Shanghai Cooperation Organization Partnership and International Technology Cooperation Plan of Science and Technology Projects(2023E01018,2025E01056)the Chinese Academy of Sciences President’s International Fellowship Initiative(PIFI)(2024VBC0006).
文摘Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges.There has been a lack of a comprehensive and multidimensional assessment to inform strategic conservation planning.Therefore,this study integrated 4 key biodiversity indices including species richness(SR),phylogenetic diversity(PD),threatened species richness(TSR),and endemic species richness(ESR)to map species diversity distribution patterns,identify conservation gaps,and elucidate their effects of climatic factors.This study revealed that species diversity shows a clear trend of decreasing from the western region to the eastern region of Tajikistan.The central–western mountains(specifically the Gissar-Darvasian and Zeravshanian regions)emerge as irreplaceable biodiversity hotspots.However,we found a severe spatial mismatch between these priority areas and the existing protected areas(PAs).Protection coverage for all hotspots was alarmingly low,ranging from 31.00%to 38.00%.Consequently,a critical 64.80%of integrated priority areas fall outside of the current PAs,representing a major conservation gap.This study identified precipitation seasonality and isothermality as the principal drivers,collectively explaining over 50.00%of the diversity variation and suggesting high vulnerability to hydrological shifts.Furthermore,we detected significant geographic sampling bias in the public biodiversity databases,with the most critical hotspot being systematically under-sampled.This study provides a robust scientific basis for conservation action,highlighting the urgent need to strategically expand PAs in the under-protected southwestern region and to mitigate critical sampling gaps through targeted data digitization and field surveys.These measures are indispensable for securing Tajikistan’s unique biodiversity and achieving the Kunming-Montreal Global Biodiversity Framework Target 3(“30×30 Protection”).
基金Supported by the National Natural Science Foundation of China(No.32172979)the Natural Science Foundation of Fujian Province(No.2021J05159)the 2023 Special Program for Promoting High-Quality Development of Marine and Fishery Industry in Fujian Province(No.PJHYF-L-2023-2)。
文摘The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The main distribution area of the C. angulata is located in Fujian, South China. In total, 420 C. angulata were collected from 14 natural habitats(populations) along the Fujian coast, and their genetic diversity and structure were analyzed in the mitochondrial COI and nuclear gene ITS2 sequences. Results reveal that all the 14 populations of C. angulata exhibited high levels of genetic diversity, with a total of 57(haplotype diversity: 0.811±0.016) and 124(haplotype diversity: 0.912±0.007) haplotypes revealed by COI and ITS2, respectively. Notably, significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ) population(FS T by COI: 0.035–0.142, P<0.05;FS T by ITS2: 0.078–0.123, P<0.05) with other populations were observed for the first time, which is also supported by the results of molecular variance analysis(FC T by COI: 0.105, P<0.05;FC T by ITS2: 0.086, P<0.05) and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree. Furthermore, the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations. In addition, the population dynamics analysis suggests that the C. angulata may have undergone expansion during the third ice age of the Pleistocene. These results provide a reference for the preservation and further genetic improvement of C. angulata.
基金supported by the Key Program of National Science of China(Grant No.:42030509 and 42141005)。
文摘The latitudinal diversity gradient(LDG)is one of the most notable biodiversity patterns in biogeography.The metabolic theory of ecology(MTE)explains ecological patterns,including the LDG.However,little is known about whether the LDG remains stable over time as climate warming progresses and whether MTE remains applicable to clarify this pattern.In this study,forest data spanning temperate,subtropical,and tropical zones across China were used to analyze long-term changes in the LDG of tree species over 2005-2020.Based on the MTE framework,spatial scales were considered to assess temperature dependence of typical forest trees species.Our results show that species richness decreased with increasing latitude,and that temperature was the primary driver of this change.Although temperature in China has significantly increased over the past two decades,the LDG of tree species has remained stable.However,there was a decrease in species richness in tropical regions over time.With predictions of the MTE,the logarithm of typical forest tree species richness exhibited negative linear relationships with the inverse of ambient temperature,indicating temperature dependence of species richness.However,the relationship remained stable and was strongly influenced by spatial scale,intensifying as spatial scale increased.The findings emphasize the important role of temperature in shaping the LDG.The effects of spatial scale,in particular,should be considered when biodiversity management plans are developed for future climate change.
基金funded by the Key Research Program of Frontier Sciences,CAS(ZDBS-LY-7001)the National Natural Science Foundation of China(32170398,42211540718,W2433074,32071541)+6 种基金the CAS“Light of West China”Programthe Xingdian Talent Support Program of Yunnan Province(XDYC-QNRC-2022-0026)the Natural Science Foundation of Yunnan(202201AT070222)the Fund of Yunnan Key Laboratory of Crop Wild Relatives Omics(CWR-2024-04)funding from the China Scholarship Council(202304910135,202304910138)for their oneyear study at the University of Toronto,Canadathe Pakistan Science Foundation&NSFC for the joint venture under the project(PSF-NSFC/JSEP/BIO/COAU(04))surpported by the Innovation Program of Shanghai Municipal Education Commission(2023ZKZD36).
文摘Mountains serve as exceptional natural laboratories for studying biodiversity due to their heterogeneous landforms and climatic zones.The Himalaya,a global biodiversity hotspot,hosts rich endemic flora,supports vital ecosystem functions,and offers a unique window into multifaceted plant diversity patterns.This review synthesizes research on Himalayan plant diversity,including species,phylogenetic,functional,and genetic dimensions,highlighting knowledge gaps and solutions.Research on Himalayan plant diversity has developed significantly.However,gaps remain,especially in studies on phylogenetic and functional diversity.The region's vegetation ranges from tropical rainforests to alpine ecosystems,with species richness typically following a hump-shaped distribution along elevation gradients.The eastern Himalaya exhibits higher plant diversity than the central and western regions.Low-elevation communities were found to be more functionally diverse,whereas high-elevation communities displayed greater ecological specialization.Communities at mid-elevations tend to show greater phylogenetic diversity than those at higher and lower elevations.The eastern and western flanks of the Himalaya retain high levels of genetic diversity and serve as glacial refugia,whereas the central region acts as a hybrid zone for closely related species.Himalayan plant diversity is shaped by historical,climatic,ecological and anthropogenic factors across space and time.However,this rich biodiversity is increasingly threatened by environmental change and growing anthropogenic pressures.Unfortunately,research efforts are constrained by spatial biases and the lack of transnational initiatives and collaborative studies,which could significantly benefit from interdisciplinary approaches,and other coordinated actions.These efforts are vital to safeguarding the Himalayan natural heritage.
基金supported by the National Natural Science Foundation of China(32130013,32070434)the National Key Research and Development Program of China(2022YFC2601601)+1 种基金the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK05010112,2019QZKK0304-02)Hainan Tropical Rainforest Conservation Research Project,ZDYF2023RDYL01(supported by the Hainan Institute of National Park,HINP,KY-24ZK02).
文摘Understanding the genetic diversity–area relationship(GAR)is essential for comprehending how species adapt to environmental changes,as genetic diversity is an indicator of a species’adaptive potential.Variation in environmental adaptation capacity exists among species and animal taxa with different distribution areas,highlighting the importance of understanding the GAR.To obtain a more comprehensive understanding of the GAR in terrestrial vertebrates,we assessed both haplotype diversity–area and nucleotide diversity–area relationships using 25,453 cytochrome c oxidase subunit I(COI)sequences from 142 amphibian species,574 bird species,and 342 mammal species.We found that both measures of genetic diversity increased with species range size across major animal groups.Nevertheless,the GAR did not differ among animal groups,while haplotype diversity performed better than nucleotide diversity in profiling the GAR,as indicated by higher R2 values.The difference in the modeling fit may stem from the distinct biological and mathematical significance of nucleotide diversity and haplotype diversity.These results suggest that the GAR follows similar rules among different animal taxa.Furthermore,haplotype diversity may serve as a more reliable indicator for assessing the potential effects of area size changes on animal populations and provide better guidance for conserving genetic diversity.
基金funded by the National Research,Development and Innovation Office(NKFIH FK 142428 grant)The contribution of Z.B.was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences and by the New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research,Development and Innovation Fund(ÚNKP-23-5-SZTE-697)+2 种基金K.F.was supported by the New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research,Development and Innovation Fund(ÚNKP-23-3-SZTE-441)C.T.was supported by the NKFIH K 146137 grantA.E-V.was supported by the long-term research development project of the Czech Academy of Sciences(RVO 67985939).
文摘Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental conditions that facilitate the persistence of species during environmental changes and exhibit unique ecoevolutionary dynamics.However,our knowledge about how topographic complexity and related ecoevolutionary selective forces influence the functional and phylogenetic signatures of species assemblages in microrefugia is very limited.Although the conceptual framework on the systematic integration of plant functional traits into the study of refugia is well established,more empirical studies on functional trait composition and functional diversity in refugia are urgently needed for more effective conservation.Here we analyzed the distribution of various plant functional traits and phylogenetic patterns in microhabitats(south-and north-facing slopes,and bottoms)of 30 large topographic depressions(i.e.doline microrefugia)and microhabitats of the surrounding plateaus in two distant forested karst regions.We found that plant assemblages in the understory of dolines and their surroundings are characterized by unique functional values and combinations of traits.Doline bottoms had the highest functional diversity among doline microhabitats and supported plant assemblages with considerably different trait compositions from the plateaus.Bottoms also had the highest phylogenetic diversity.These results suggest that topographic complexity in forested dolines has a significant effect on the distribution of plant functional traits in the understory.High functional and phylogenetic diversity in doline bottoms can have important consequences for the long-term survival of plant populations,highlighting that these microhabitats may provide a higher resilience and support an adaptive community-level response to natural and anthropogenic stressors.Understanding mechanisms that drive the survival of species within microrefugia is required to determine the best conservation and management strategies.
基金supported by the National Natural Science Foundation of China(No.32271734)。
文摘The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic diversity,with relatively less research on functional and phylogenetic diversity.In this study,we examined the phylogenetic and functional diversity and underlying influencing factors of bird communities in 37 urban parks in Nanjing,China.We conducted a systematic survey of bird communities in Nanjing urban parks and selected six park characteristics that are generally considered to affect bird diversity.Model selection based on corrected Akaike Information Criterion(AICc)and model averaging showed that park area,habitat diversity and building index(a proxy for the degree of urbanization)were significant factors affecting avian phylogenetic and functional diversity in Nanjing urban parks.Specifically,habitat diversity and park area were positively correlated with bird diversity,while the building index was negatively correlated with bird diversity.Moreover,the phylogenetic and functional structures of urban bird communities exhibited a clustered pattern,indicating that environmental filtering might play a role in shaping community composition.In addition,building index had certain impact on the construction of bird phylogenetic communities in urban parks.Our results suggest that expanding park areas,increasing habitat diversity and reducing building indexes may be effective measures to increase the avian phylogenetic and functional diversity in our system.
基金supported by the National Natural Science Foundation of China(32271743).
文摘Urban wetlands are considered as"habitat islands"within the urban matrix that contribute to species conservation.Waterbirds are sensitive pollution indicators in terrestrial and aquatic ecosystems,and their diversity in urban wetlands reflects the response of wildlife to urbanization.However,very few studies have investigated seasonal differences in the multidimensional diversity of waterbirds in urbanized landscapes.In this study,we analyzed various wetland parameters that could potentially affect the seasonal variations in multidimensional diversity of waterbirds in Nanjing,China.We surveyed waterbirds in 29 urban wetlands using the point count method during breeding and non-breeding seasons from November 2022 to June 2023.We then employed multiple linear regressions and information-theoretic approaches to investigate the impact of wetland characteristics on waterbird diversity.We found that water body area and buffer zone connectivity consistently emerged as positive factors affecting waterbird taxonomic and phylogenetic diversity across seasons.Conversely,the urbanization synthetic index was negatively correlated with waterbird diversity only during the breeding season.Regarding functional diversity,we found that the positive correlation between buffer zone connectivity and waterbird diversity was specific to the breeding season.Therefore,for effective conservation of waterbird diversity in our system,wetland planning should prioritize expanding wetland water body areas,enhancing wetland connectivity,minimizing human disturbance during the breeding season,and implementing ecological restoration measures in urbanized wetlands to mitigate adverse effects of urbanization.
文摘Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored variations in composition, diversity, cover,and life forms of vascular plants along a complete altitudinal gradient(1300-4000 m a.s.l) in Sierra de Velasco, an arid mountain in northwestern Argentina.We evaluated the influence of environmental variables on plant diversity and cover. Field sampling was conducted in the northern sector of the Sa. de Velasco,on the western slope in eight 50 m wide altitudinal bands at 400 m elevation intervals. We used rectangular plots(20 × 4 m;n:10/altitudinal band) to register the vascular plants of all the growth forms, and linear transects(20 m long.;n:30/altitudinal band) to quantify the vegetation cover using the point intercept method. Diversity was calculated using hill numbers.Data analysis included non-metric multidimensional scaling(NMDS), indicator species analysis,generalized linear models(GLMs), and variance partitioning analysis. A total of 232 species from 51families and 158 genera were registered. Species composition showed greater similarity at intermediate elevations. Plant diversity and cover exhibited a unimodal distribution, peaking at intermediate elevations(2100-2500 m). In contrast, life forms' distribution showed divergent patterns. Therophytes and succulents predominated at low altitudes,phanerophytes and hemicryptophytes at medium altitudes, and chamaephytes and geophytes at high altitudes. The altitudinal patterns of plant diversity and cover were primarily driven by climatic factors.Conservation efforts in the Sierra de Velasco should focus on the middle and upper zones due to their high biodiversity and vulnerability to climate change.
基金supported by the National Key Research and Development Programme of China(No.2023YFC3206903)the Natural Science Foundation of China(No.51938010)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.SJCX23_1717).
文摘Red anaerobic ammonia oxidation (Anammox) granular sludge (AnGS) has been reported insuccessfully operating Anammox systems, and its color is associated with sludge activity.However, in long-term operating systems, AnGS exhibits different sensory colors, physicalstructures, community structures, and denitrification performance, but the relationship betweenthem has not yet been elucidated.The AnGS of the Anammox system, which has beenin operation for more than a decade, can be divided into twomain categories: red and white.The specific Anammox activity (SAA) in conventional red AnGS increased continuously asthe particle size increased from <0.51 mm to 6.02 ± 0.84 mm. The SAA of white AnGS wereslightly lower than those of red AnGS with similarly-size granules but significantly higherthan AnGS with smaller red granules. Compared with red AnGS, the extracellular polymericsubstances of white AnGS were significantly reduced,mainly due to the higher intracellulariron content, resulting in lower heme c concentration. Thus, heme c may prove not to bean evaluative tool for measuring Anammox activity. Red and white AnGS, whether throughself-aggregation or adsorption by hydroxyl apatite and other carriers, will face the fate ofinternal voids during particle size growth. White AnGS exhibited amore complex microbialcommunity than red AnGS. Candidatus Brocadia was abundant in red AnGS and the abundanceincreased with increasing granule size. Candidatus Kuenenia and Candidatus Jetteniamade significant contributions to denitrification in white AnGS. This study provides a newperspective on particle selection for anammox engineering applications.
基金supported by the National Natural Science Foundation of China(grant number 31901109)Guangdong Basic and Applied Basic Research Foundation(grant number 2021A1515110744).
文摘Understanding how and why assemblage dissimilarity changes along spatial gradient is a great challenge in ecology,because answers to these questions depend on the analytical types,dimensions,and components of beta diversity we concerned.To obtain a comprehensive understanding of assemblage dissimilarity and its implications for biodiversity conservation in the Himalayas,we explored the elevational patterns and determinants of beta diversity and its turnover and nestedness components of pairwise and multiple types and taxonomic and phylogenetic dimensions simultaneously.Patterns of beta diversity and their components of different types and dimensions were calculated based on 96 sampling quadrats along an 1800-5400 m elevational gradient.We examined whether and how these patterns differed from random expectations using null models.Furthermore,we used random forest methods to quantify the role of environmental variables representing climate,topography,and human disturbance in determining these patterns.We found that beta diversity and its turnover component,regardless of its types and dimensions,shown a hump-shaped elevational patterns.Both pairwise and multiple phylogenetic beta diversity were remarkably lower than their taxonomic counterpart.These patterns were significantly less than random expectation and were mostly associated with climate variables.In summary,our results suggested that assemblage dissimilarity of seed plants was mostly originate from the replacement of closely related species determined by climate-driven environmental filtering.Accordingly,conservation efforts should better cover elevations with different climate types to maximalize biodiversity conservation,rather than only focus on elevations with highest species richness.Our study demonstrated that comparisons of beta diversity of different types,dimensions,and components could be conductive to consensus on the origin and mechanism of assemblage dissimilarity.
基金the National Key Research and Development Program of China(2023YFF1304302)the Qaidam basin and Qilian Mountains germplasm resources collection project(Grant No.SJCZFY2022-1-6)。
文摘Understanding plant diversity within geographical ranges and identifying key species that drive community variation can provide crucial insights for the management of grasslands.However,the contribution of both local sites and plant species to beta diversity in grassland ecosystems has yet to be accurately assessed.This study applied the ecological uniqueness approach to examine both local contributions to beta diversity(LCBD)and species contributions to beta diversity(SCBD)across six major geographical ranges in alpine grasslands.We found that LCBD was driven by species turnover,with climate,plant communities,and their interactions influencing LCBD across spatial scales.LCBD values were high in areas with low evapotranspiration,high rainfall variability,and low species and functional richness.Precipitation seasonality predicted large-scale LCBD dynamics,while plant community abundance explained local LCBD variation.In addition,we found that SCBD were confined to species with moderate occupancy,although these species contributed less to plant biological traits.Our findings are crucial for understanding how ecological characteristics influence plant beta diversity in grasslands and how it responds to environmental and community factors.In addition,these findings have successfully identified key sites and priority plants for conservation,indicating that using standardized quadrats can support the assessment of the ecological uniqueness in grassland ecosystems.We hope these insights will inform the development of conservation strategies,thereby supporting regional plant diversity and resisting vegetation homogenization.
文摘The authors regret that an error occurred during the preparation of their article:One of the official databases,which was used for functional trait collections,contained an incorrect term–'chametophytes'–for the life form category'chamaephytes'.Unfortunately,this incorrect term was used throughout the article following the nomenclature of this official database:in one instance in the main text,in Fig.3 and its caption,in Fig.5,and in two instances in the supplementary material.
文摘On the morning of May 31st,the parallel forum"Seeking Harmony without Uniformity in Mutual Learning:Diversity of Civilisations from the Sinologists'Perspective"was held in Dunhuang.The forum was hosted by the Chinese Association for International Understanding and organised by Beijing Language and Culture University.Leading Sinologists and Chinese culture researchers from Europe,Asia and Latin America gathered to discuss the theme of civilisational diversity and explore pathways for coexistence and mutual enrichment.
基金funded by the Empresas Públicas de Medellín and Universidad de Antioquia.
文摘Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental gradients can influence this diversity through mechanisms such as gene flow, selection, and genetic drift. To explore how these forces interact, we assessed neutral and adaptive genetic variation in three widely distributed and two narrowly distributed bird species co-occurring along the Cauca River canyon in Antioquia, Colombia—a region of pronounced environmental heterogeneity. We sampled individuals across eight sites spanning the canyon's gradient and analyzed genetic diversity and structure using microsatellites and toll-like receptors (TLRs), a gene family involved in innate immunity. Widely distributed species consistently exhibited higher genetic diversity at both marker types compared to their narrowly distributed counterparts. Although we did not find a significant relationship between microsatellite heterozygosity and TLR heterozygosity, we evidenced a negative trend for widely distributed species and a positive trend for narrowly distributed species. This result suggests that there is a stronger effect of genetic drift in narrowly distributed species. Our results highlight the role of distribution range in maintaining genetic diversity and suggest that environmental gradients, by interacting with gene flow and selection, may influence patterns of adaptive variation.
基金financially supported by the National Natural Science Foundation of China(U20A2007 and 32160343)the Open Project of Key Laboratory of the Alpine Grassland Ecology in the Three Rivers Region(Qinghai University),Ministry of Education of China(2023-SJY-KF-02)the West Light Foundation of the Chinese Academy of Sciences。
文摘The response of plant functional diversity to external disturbances not only effectively predicts changes in the ecosystem but it also reflects how plant communities use external environmental resources.However,research on how different herbivore assemblages affect plant functional diversity is limited.Therefore,this study systematically explored the effects of three typical herbivore assemblages(yak grazing,Tibetan sheep grazing,and mixed grazing by yaks and Tibetan sheep)on species richness,plant functional diversity,and soil physicochemical properties in alpine grasslands on the Qinghai-Tibet Plateau,China.This study further investigated the primary mechanisms driving the changes in plant functional diversity.The results indicate four key aspects of this system:(1)Grazing significantly enhanced plant functional diversity,particularly when the mixed grazing by yaks and Tibetan sheep was applied at a ratio of 1:2.This ratio showed the most substantial improvement in the functional dispersion index and Rao's quadratic entropy index.(2)Compared to enclosed treatments,grazing increased species richness andβ-diversity,contributing to higher plant functional diversity.(3)Grazing treatments affected various plant traits,such as reducing plant community height and leaf thickness while increasing specific leaf area.However,the impact on plant functional diversity was most pronounced under the mixed grazing by yaks and Tibetan sheep at a ratio of 1:2.(4)Speciesα-diversity was positively correlated with plant functional diversity.Changes in plant functional diversity were primarily regulated by variations in soil physicochemical properties.Specifically,increases in soil available nitrogen significantly promoted changes in plant functional diversity,while increases in soil available potassium and bulk density had a significant inhibitory effect on these changes.Long-term grazing significantly reduced the height of plant communities in alpine meadows,while a balanced mixture of yak and Tibetan sheep grazing,especially at a ratio of 1:2,enhanced plant functional diversity the most.This suggests that,under these conditions,the use of external environmental resources by the plant community is optimized.
