Predicting whether alien species will invade a native community is a key challenge in invasion ecology.One factor that may help predict invasion success is phylogenetic relatedness.Darwin proposed that closely related...Predicting whether alien species will invade a native community is a key challenge in invasion ecology.One factor that may help predict invasion success is phylogenetic relatedness.Darwin proposed that closely related species tend to share similar niches,although this relationship may be influenced by various ecological and evolutionary factors.To test this,we classified alien Asteraceae species in China into three categories based on their invasion status and the extent of ecological damage:introduced,naturalized,and invasive.We then compared the genetic relationships and niche overlap between alien and native Asteraceae species.We found that invasive Asteraceae species are more closely related to native Asteraceae species than are introduced and naturalized species.However,alien Asteraceae species(including introduced,naturalized,and invasive species)exhibited relatively low niche overlap with native Asteraceae species.These findings suggest that the main premise underlying Darwin’s naturalization conundrum,namely,the universality of phylogenetic niche conservatism,may not hold true.Instead,our findings indicate that alien species are more likely to invade successfully when they are more closely related to native plants,exhibit less niche overlap,and maintain conservative niches during the invasion process.These findings provide new insights into the mechanisms of alien plant invasions,highlight the relationship between alien species invasions and native community vulnerability,and offer important insights into the development of effective biological invasion management strategies.展开更多
[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in t...[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in the Upper Yangtze River.This study initiated continuous monitoring of natural spawning habitats from February 2022 to assess these ecological changes.[Methods]Environmental DNA(eDNA)metabarcoding was employed to analyze fish species composition,biodiversity patterns,and niche parameters of dominant species.Water sampling followed the CEN/TS 19461 standard across five monitoring transects(ZT1-ZT5).[Results]The eDNA analysis detected 45 species of fish belonging to 38 genera,13 families,and 3 orders were detected through environmental DNA(eDNA)in this survey,including 10 species endemic to the upper reaches of the Yangtze River,such as Procypris rabaudi and Myxocyprinus asiaticus.The fish community was mainly composed of bottom-dwelling,settling ovum-producing,omnivorous fish.The variation ranges of the Chao1 index,ACE index,Shannon index,and Simpson index are 736~996,719~965,1.58~3.23,and 0.83~0.99,respectively,indicating that fish species in spawning sites are abundant and community distribution uniformity is high.All indexes are highest at ZT1 monitoring points.Cluster analysis showed that,at a certain similarity level,fish community types in spawning sites could be basically divided into two groups:ZT1,ZT3,and ZT5 clustered together,and ZT2 and ZT4 clustered together,indicating similar fish community habitats.There are 9 dominant fish species in typical deep pool habitats in the reserve,with niche widths(Bi)ranging from 1.13 to 3.87.The dominant fish species are broad and medium niche fish,such as Cyprinus carpio and Hemiculter tchangi,with the niche overlap index(Oik)of some dominant fish species reaching more than 0.95.This indicates fierce competition for resources among the fish in this spawning ground.[Conclusion]The Zhutuo spawning ground demonstrates high species richness with homogeneous community structure and intense resource competition.This study establishes an eDNA-based monitoring framework that enhances conventional survey method,providing critical baseline data for adaptive management under the fishing moratorium regime.展开更多
Habitat fragmentation poses a significant threat to bird communities, especially those in open and semi-open ecosystems such as steppes. This study investigates how steppe birds adapt to and utilize fragmented habitat...Habitat fragmentation poses a significant threat to bird communities, especially those in open and semi-open ecosystems such as steppes. This study investigates how steppe birds adapt to and utilize fragmented habitats by combining niche modeling with ecological trait analysis. We conducted standardized point surveys to examine the habitat preferences of 32 bird species in Inner Mongolia, China, and quantified their habitat niche parameters using the Outlying Mean Index (OMI). Our results reveal distinct habitat preferences among species, with some thriving in intact environments while others are better adapted to fragmented areas. Grassland species showed high specialization along the fragmentation gradient, while others exhibited adaptability to varying levels of fragmentation. Using a Generalized Additive Model (GAM), we identified three key traits influencing habitat occupancy: hand-wing index, body mass, and range size. Specifically, species with medium hand-wing indices, moderate body mass, and larger range sizes were more likely to occupy heavily fragmented habitats. These findings provide empirical evidence on how habitat fragmentation affects bird species in steppe ecosystems. The study highlights the importance of functional traits in understanding avian responses to habitat fragmentation and offers a foundation for developing effective conservation strategies to preserve biodiversity in fragmented landscapes.展开更多
Accurate capture and presentation of the interactive feedback relationships among various objectives in multi-objective reservoir operation is essential for maximizing operational benefits.In this study,the niche theo...Accurate capture and presentation of the interactive feedback relationships among various objectives in multi-objective reservoir operation is essential for maximizing operational benefits.In this study,the niche theory of ecology was innovatively applied to the field of reservoir operation,and a novel state-relationship(S-R)measurement analysis method was developed for multi-objective reservoir operation.This method enables the study of interaction among multiple objectives.This method was used to investigate the relationship among the objectives of power generation,water supply,and ecological protection for cascade reservoir operation in the Wujiang River Basin in China.The results indicated that the ecological protection objective was the most competitive in acquiring and capturing resources like flow and water level,while the water supply objective was the weakest.Power generation competed most strongly with ecological protection and relatively weakly with water supply.These findings facilitate decision-making throughout the reservoir operation process in the region.The S-R method based on the niche theory is convenient,efficient,and intuitive,allowing for the quantification of feedback relationships among objectives without requiring the solution of the Pareto frontier of a multi-objective problem in advance.This method provides a novel and feasible idea for studying multi-objective interactions.展开更多
The transformation of natural habitats into human-modified landscapes has far-reaching consequences for species distribution and abundance.As species adapt to these changing environments,shifts in distribution pattern...The transformation of natural habitats into human-modified landscapes has far-reaching consequences for species distribution and abundance.As species adapt to these changing environments,shifts in distribution patterns,niche dynamics,and interspecies interactions may occur,impacting biodiversity at multiple levels and potentially leading to ecosystem imbalances.This study aims to assess the impact of variations in vegetation composition and human disturbance on the distribution of sympatric breeding birds and to determine the extent of niche overlap or differentiation among these species.We conducted field surveys and collected data on bird distribution,vegetation composition,and level of human disturbance in eastern Inner Mongolian grasslands.We focused on the six most frequently co-occurring breeding birds,representing a mix of sparrows,larks,and corvids.Generalized Additive Models revealed varying responses of species occurrence along habitat gradients.Species like the Eurasian Skylark(Alauda arvensis),Mongolian Lark(Melanocorypha mongolica),and Asian Shorttoed Lark(Calandrella cheleensis),increased in larger and more connected habitats,while others,like the Tree Sparrow(Passer montanus),Eurasian Magpie(Pica pica),and Barn Swallow(Hirundo rustica),adapted to more fragmented habitats.Niche analysis indicated habitat generalists tended to occupy larger niches than grassland specialists.Substantial niche overlap was also found among the six co-occurring bird species.Conservation efforts should consider the specific needs of specialist species and strive to maintain or restore critical grassland habitats.Additionally,promoting sustainable agricultural practices that balance the needs of birds and human activities can contribute to the coexistence of generalist and specialist bird species in modified landscapes.展开更多
The formation of pantropical intercontinental disjunction(PID)in plants has generally been attributed to vicariance,boreotropical migration,and long-distance dispersal.However,this pattern has primarily been examined ...The formation of pantropical intercontinental disjunction(PID)in plants has generally been attributed to vicariance,boreotropical migration,and long-distance dispersal.However,this pattern has primarily been examined in herbs,shrubs,and trees,and less commonly studied in interlayer plant taxa.Here we examined evolutionary processes that resulted in the PID of a pantropical woody liana,Uncaria(Rubiaceae).We first constructed a comprehensive phylogeny by employing 73 plastid protein-coding sequences from 29 accessions of Uncaria(including 16 newly sequenced)from different continents.We then inferred divergence time,history and ecological niche evolution of this genus.Our results showed that Uncaria consisted of four well-supported clades that belonged to two geographically distinct lineages:the Asia-Oceania lineage and the Afro-Neotropical lineage.Biogeographic reconstruction showed this genus likely originated in Asia during the early Miocene(ca.19.03 Ma)and the Middle Miocene Climatic Optimum may have triggered the early diversification of Uncaria.Due to its recent origin and small seeds with long wings,wind or water-mediated long-distance dispersal may have contributed to the distribution of Uncaria in tropical Oceania(via stepping-stone dispersal)and tropical Africa and America(by transoceanic dispersal).Our findings also indicate that diversification of Uncaria was primarily driven by ecological niche divergence,particularly climatic factors.Our study emphasizes the dual role of climatic niche divergence and long-distance dispersal in shaping the PID of Uncaria,providing references for many other extant lineages with similar distributions.展开更多
Background:The traditional Chinese medicine compound Sancao decoction(SCD)is a folk prescription for regulating immunity.It is composed of 8 Chinese herbal medicines,such as Prunellae Spica(Xiakucao),Houttuyniae Herba...Background:The traditional Chinese medicine compound Sancao decoction(SCD)is a folk prescription for regulating immunity.It is composed of 8 Chinese herbal medicines,such as Prunellae Spica(Xiakucao),Houttuyniae Herba(Yuxingcao),Lysimachiae Herba(Jinqiancao)and so on.In cancer,the interleukin-6(IL-6)/the signal transducer and the activator of transcription 3(STAT3)pathway directly promotes the proliferation,survival and angiogenesis of cancer cells,and arginase-1(ARG-1)is a key enzyme for myeloid-derived suppressor cells(MDSCs)to exert immunosuppressive function.It is not clear whether SCD regulates the expression of ARG-1 in MDSCs through the IL-6/STAT3 pathway.Therefore,we explored the effect and mechanism of SCD on lung metastasis of breast cancer.Methods:The components in SCD have been analyzed by HPLC-MS.A spontaneous metastasis model of breast cancer was established by injecting 4T1 cells into the mammary fat pad of BALB/c mice.Pre-metastatic niche(PMN)formation and the role of SCD on PMN were evaluated by lung metastasis nodules,lung pathology tests and immunofluorescence for 2–4 weeks.Serum tests and hematoxylin-eosin staining(H&E)were used to evaluate the side effects of cisplatin.Western blot and ELISA were used to detect proteins and cytokines of the STAT3 signaling pathway in mouse lung tissue.Results:Compared with SCD or cisplatin treatment alone,SCD/cisplatin(CP)synergistic administration not only significantly inhibited orthotropic breast tumor growth,but also reduced lung metastasis and alleviated the hepatorenal toxicity induced by CP in vivo.Remarkably,the combination effectively inhibited PMN formation and the accumulation of MDSCs in the lung PMN,accompanied by the significant infiltration of CD4+T and CD8+T-lymphocytes in the lung PMN and spleen.In addition,the SCD/CP combination downregulated protein expression levels of STAT3,p-STAT3,IL-6 and ARG-1 in the lung PMN of breast cancer mice.Conclusion:The synergistic effect of SCD and cisplatin inhibited MDSCs aggregation and the immunosuppressive function of pulmonary PMN,thereby remodeling the immunosuppressive tumor microenvironment and enhancing anti-tumor immunity,leading to remission of orthotopic breast cancer and lung metastases and amelioration of cisplatin-induced liver and kidney toxicity.展开更多
Subterranean environments are buffered from external climatic fluctuations due to the absence of light and a delayed thermal response to surface conditions(Mammola 2019).Terrestrial salamanders are often found in subt...Subterranean environments are buffered from external climatic fluctuations due to the absence of light and a delayed thermal response to surface conditions(Mammola 2019).Terrestrial salamanders are often found in subterranean habitats,but few studies have assessed the influence of climatic effects on their long-term spatial distribution and niche breadth.In this study,we investigated the variability over 29 consecutive years of the spatial niche in a terrestrial salamander population inhabiting an artificial subterranean habitat.We hypothesized that juvenile salamanders,which are typically active near cave entrances and more exposed to climatic variability and dehydration(Peterman et al.2013),would exhibit an earlier and more variable behavioral adaptation to increasing external temperatures compared to adults.展开更多
Two widespread bird species in Sri Lanka’s dry zone,Pycnonotus cafer(Red-vented Bulbul,RVBB)and Pycnonotus luteolus(White-browed Bulbul,WBBB),were studied to understand their foraging dynamics and ecology.The researc...Two widespread bird species in Sri Lanka’s dry zone,Pycnonotus cafer(Red-vented Bulbul,RVBB)and Pycnonotus luteolus(White-browed Bulbul,WBBB),were studied to understand their foraging dynamics and ecology.The research was conducted from October 2022 to February 2023 in Mihintale Sanctuary(80.30′11.24″E,8.21′04.63″N)and the Faculty of Applied Sciences,Rajarata University of Sri Lanka(80.502206″E,8.353090″N).Data were obtained through focal sampling,opportunistic observations,and mist netting.Both species predominantly foraged on twigs,using gleaning as the dominant food-handling technique.RVBB foraged mostly at the canopy level,while WBBB foraged primarily at the sub-canopy level.Fruits constituted the major food type for both species.RVBB and WBBB utilized 10 and 7 plant species,respectively,with Grewia helicterifolia being the primary foraging plant.Minimal foraging was observed on Croton sp.(RVBB)and Hugonia mistax(WBBB).The correlation between nutritional components and the consumption of both species revealed a preference for foods with lower protein,higher fat,and ash content.There was no linear correlation between gape width and fruit size(r=-0.21,P=0.69)for both species.The standardized dietary niche breadth indicated both species are specialists,with a high pairwise dietary niche overlap(0.9854).These findings highlight the niche-specific foraging adaptations of RVBB and WBBB within Mihintale,emphasizing their distinct strategies in utilizing plant species,fruit sizes,and foraging heights.Understanding such ecological dynamics is essential for habitat conservation efforts and ensuring the availability of key foraging resources for these species in the dry zone.展开更多
Urbanization and industrialization have heightened the risk of groundwater contamination in karst regions,threatening the safety of petrifying spring water.Petrifying spring-moss systems serve as critical interfaces f...Urbanization and industrialization have heightened the risk of groundwater contamination in karst regions,threatening the safety of petrifying spring water.Petrifying spring-moss systems serve as critical interfaces for groundwater-surface water interaction,retaining potentially toxic elements(PTEs)and improving water quality in karst ecosystems.However,it remains uncertain whether the niche differentiation among moss species influences their capacity for the retention of PTEs.This study examines the petrifying spring-moss system in Tongren Grand Canyon,Guizhou Province,a typical karst region in southwestern China.Four dominant moss species with distinct ecological niches were selected for this study.Inductively coupled plasma mass spectrometry(ICPMS)was used to quantify PTEs in the petrifying springmoss systems and their associated water flows.Ecological niche analysis was integrated to evaluate the PTEs enrichment efficiencies of different petrifying spring-moss systems.The results identified Fissidens grandifrons Brid.,Hydrogonium majusculum(C.Muell.)Chen,Brachythecium curtum(Lindb.)Limpr.,and Cratoneuron filicinum(Hedw.)Spruc.var.filicinum as representative species of distinct ecological niches.After filtration through the petrifying spring-moss systems,the concentrations of PTEs in the water were significantly reduced(P<0.05).The retention capacities of moss species varied significantly across ecological niches and were ranked as follows:C.filicinum var.filicinum>B.curtum>F.grandifrons>H.majusculum.This study demonstrates that karst petrifying spring-moss systems efficiently intercept PTEs in groundwater and reveals,from a niche theory angle,the link between moss niche differentiation and their retention efficiency,which offers innovative strategies for ecological remediation of PTEs pollution in global karst groundwater systems.展开更多
Studying coexistence mechanisms is practically important for understanding and conserving marine biodiversity and community structure. Tropical marine ecosystems may exhibit higher competition between top predators du...Studying coexistence mechanisms is practically important for understanding and conserving marine biodiversity and community structure. Tropical marine ecosystems may exhibit higher competition between top predators due to generally low primary productivity and pronounced seasonal fluctuation in food availability. Consequentially, niche segregation in sympatric breeding seabirds is expected to occur as a mechanism to maintain species coexistence. However, a single-dimensional study on seabird niche segregation might result in unclear niche overlap. Here, we investigated multi-dimensional niche segregation of tropical seabirds during field expeditions to the Xisha Archipelago, China, in 2023. We reconfirmed the breeding status of six species of terns and noddy, and further revealed the multi-dimensional niche segregation among Black-naped (Sterna sumatrana), Bridled (Onychoprion anaethetus) and Roseate (Sterna dougallii) Terns. Spatially, these three species utilized nest sites that differentiated by vegetation and distance to sea. Temporally, Black-naped Terns bred earlier and for a longer period, while Bridled and Roseate Terns had more restricted breeding seasons. Furthermore, the daily foraging activity patterns of these species also differed, with Bridled Terns potentially having a longer foraging time at noon. In terms of diet, Bridled Terns were opportunists that fed on fishes, squids and insects, such as migratory fruit-piercing moths, while Roseate Terns were primarily piscivorous, especially feeding on Exocoetidae (flying fishes). Seabirds play a crucial role in marine ecosystems and are globally threatened. Our findings shed light on the complex mechanisms facilitating the coexistence of sympatric seabird species in China. Further research is needed to examine other ecological interactions and to develop effective conservation strategies for protecting these valuable seabird populations.展开更多
Anthropogenic disturbances are causing significant impacts on plant distribution worldwide,and many of these effects are driven by changes in the recruitment patterns of plant species.Global warming and land-use chang...Anthropogenic disturbances are causing significant impacts on plant distribution worldwide,and many of these effects are driven by changes in the recruitment patterns of plant species.Global warming and land-use change are two major disturbances leading to changes in germination strategies by changing both soil temperature regimes and light quality reaching the seeds due to soil disturbance.Investigating the range,overlap,and redundancy of niche germination of co-occurring plant species allows us to understand whether endemic species are threatened either by native non-endemic or by alien species,especially in an ecosystem of restricted distribution such as the campo rupestre.Employing a systematic review,this study aimed to evaluate the effect of temperature increase and seed burial on the germination of endemic and non-endemic species in the campo rupestre in Brazil.We performed a metaanalysis using increased temperature and darkness as proxies for the impact of disturbance on germination patterns.In this context,we hypothesized that:increased temperature and darkness negatively influence the germination of native species and positively influence the germination of alien species in the campo rupestre.Specifically,we expect the negative effect to be more pronounced in endemic species than in native non-endemic species.Moreover,we intend to describe the role of seed size in the germination of native and alien species from campo rupestre in the context of increased temperature and darkness.Our analysis showed that increased temperature influenced the germination of alien species by ca.55%,while it did not influence the germination of endemic or native non-endemic species.Furthermore,the germination of alien species under higher temperatures was promoted by increasing seed size.Darkness negatively influenced seed germination of native species,independent of their distribution.Moreover,under darkness conditions,the germination of endemic seeds decreased with seed size.Through their direct effects on germination strategies,we conclude that warming temperatures and land-use change can lead to a long-term displacement of endemic species by native non-endemic and alien species in campo rupestre,thus compromising ecosystem services and conservation of these fragile physiognomies in the near future.展开更多
As global warming persistently alters and rapidly reshapes landscapes and habitats, conventional species distribution models relying solely on maintaining static conditions within the current climate are likely to fal...As global warming persistently alters and rapidly reshapes landscapes and habitats, conventional species distribution models relying solely on maintaining static conditions within the current climate are likely to falter, particularly at the genus level. Hence, we hypothesize that climate change will differentially affect ecological niches of the same genus species with various latitudinal positioning and local topography, and the high-latitude species may experience greater niche contraction than low-latitude species, and that mountainous regions with high elevational variability may serve as critical climate refugia. Herein, we simulate niche alterations and integrate an ensemble model(EM) strategy, taking into account species dispersal limitations factors(topography, soil, and ultraviolet), to construct a comprehensive habitat suitability(CHS) model for assessing the future vulnerability of the Betula genus, most of which are timber species in China. Our findings reveal that the niche spatial(geographic distribution) of most species(62%) within the Betula genus will undergo a gradual decline under climate change, supporting our hypothesis of latitudinal differentiation in climate vulnerability. Intriguingly, the projected high-latitude niche reduction within the genus cannot be counterbalanced by the anticipated niche expansion of closely related species in low-latitude regions, even considering the evident latitudinal gradient distribution of species. Nonetheless, the niche spatial of six Betula species in southwestern China remains stable or expands under warming scenarios, strongly supporting our secondary hypothesis about topographic buffering effects, which probably means the unique topography(i.e., the largest elevation difference) of this region may serve as a sanctuary for preserving Betula genetic diversity. Our results underscore the uncertain nature of pre-existing niche systems at the genus level under climate change, emphasizing the need for diligent resource management and conservation planning for vulnerable timber species.展开更多
The expansion of the scale of the elderly care industry,the acquisition of market share,and the seizure of high profits depend on the consistency between the ecological niche of the elderly care industry and the actua...The expansion of the scale of the elderly care industry,the acquisition of market share,and the seizure of high profits depend on the consistency between the ecological niche of the elderly care industry and the actual resource and environmental conditions.Based on the situation theory of ecological niche,this paper expands the factor of“energy”and represents the three dimensions of“state,”“potential,”and“energy”from three aspects:market niche,technology niche,and resource niche.Taking 220 listed companies as samples,this paper improves the traditional catastrophe progression evaluation model and uses structural equation modeling to test the validity of the indicator system,thereby conducting evaluation research on the ecological niche of the elderly care industry.From the results of niche potential energy measurement,the three dimensions of market niche,resource niche,and technology niche are unevenly developed,reflecting the lack of competitiveness of the elderly care industry.展开更多
To investigate the dominant species and interspecific association in the phytoplankton community of the Feiyun River basin in Zhejiang Province,East China,the main stream and the Shanxi Zhaoshandu Reservoir in the dow...To investigate the dominant species and interspecific association in the phytoplankton community of the Feiyun River basin in Zhejiang Province,East China,the main stream and the Shanxi Zhaoshandu Reservoir in the downstream were chosen as the study area,for which 22 sampling sites were designated.Sampling was conducted in September 2021,January,May,and July 2022.Phytoplankton species were identified from both quantitative samples and in-vivo observations.Phytoplankton was quantified by direct counting.Results show that there were 98 species belonging to 6 phyla and 78 genera.In addition,to clarify the niches of the dominant phytoplankton species and their interspecific association,the dominance index was calculated,and a comprehensive analysis was conducted including niche width,niche overlap value,ecological response rate,overall association,chi-square test,and the stability.The phytoplankton community exhibited characteristics of a Cyanobacteria-Chlorophyta-Diatom type community,showing higher diversity in spring and lower diversity in summer.Among 11 dominants phytoplankton species from 3 phyla,both frequency and dominance degree varied seasonally,of which Microcystis sp.was the dominant species in Spring,Autumn,and Winter.The niche widths of the dominant species ranged from 0.234 to 0.933,and were categorized into three groups.The niche overlap values of the 11 dominant species ranged from 0.359 to 0.959,exhibiting significant seasonal differences-highest in winter followed by autumn,spring,and summer in turn.The overall correlation among dominant species in all four seasons revealed a non-significant negative association,resulting in an unstable community structure.A significant portion(84.2%)of species pairs displayed positive associations,suggesting a successional pattern where Diatoms dominated while other dominant species shared resources and space.Despite this pattern,stability measurements indicated that the dominant species community remained unstable.Therefore,careful monitoring is recommended for potential water environment issues arising from abnormal proliferation of dominant species in the watershed during winter.This research built a theoretical foundation with a data support to the early warning of eutrophication and provided a reference for water resources management in similar watersheds along the eastern coast of China.展开更多
In recent years,there has been considerable exploration into methods aimed at enhancing the regenerative capacity of transplanted and/or tissue-resident cells.Biomaterials,in particular,have garnered significant inter...In recent years,there has been considerable exploration into methods aimed at enhancing the regenerative capacity of transplanted and/or tissue-resident cells.Biomaterials,in particular,have garnered significant interest for their potential to serve as natural scaffolds for cells.In this editorial,we provide commentary on the study by Wang et al,in a recently published issue of World J Stem Cells,which investigates the use of a decellularized xenogeneic extracellular matrix(ECM)derived from antler stem cells for repairing osteochondral defects in rat knee joints.Our focus lies specifically on the crucial role of biological scaffolds as a strategy for augmenting stem cell potential and regenerative capabilities,thanks to the establishment of a favorable microenvironment(niche).Stem cell differen-tiation heavily depends on exposure to intrinsic properties of the ECM,including its chemical and protein composition,as well as the mechanical forces it can generate.Collectively,these physicochemical cues contribute to a bio-instructive signaling environment that offers tissue-specific guidance for achieving effective repair and regeneration.The interest in mechanobiology,often conceptualized as a form of“structural memory”,is steadily gaining more validation and momen-tum,especially in light of findings such as these.展开更多
How animals respond to seasonal resource availability has profound implications for their dietary flexibility and realized ecological niches.We sought to understand seasonal dietary niche partitioning in extant Africa...How animals respond to seasonal resource availability has profound implications for their dietary flexibility and realized ecological niches.We sought to understand seasonal dietary niche partitioning in extant African suids using intra-tooth stable isotope analysis of enamel.We collected enamel samples from canines of red river hogs/bushpigs(Potamochoerus spp.)and third molars of warthogs(Phacochoerus spp.)in 3 different regions of central and eastern Africa.We analyzed multiple samples from each tooth and used variations in stable carbon and oxygen isotope ratios(δ^(13)C andδ^(18)O)and covariances between them to infer seasonal dietary changes.We found that most Phacochoerus display C_(4)-dominated diets,while most Potamochoerus display C_(3)-dominated diets.Phacochoerus and Potamochoerus that co-occur in the same region display no overlap in intra-toothδ^(13)C,which suggests dietary niche partitioning.They also show divergingδ^(13)C values as the dry seasons progress and convergingδ^(13)C values during the peak of the rainy seasons,which suggests a greater dietary niche separation during the dry seasons when resources are scarce than during the rainy season.We found statistically significant cross-correlations between intra-toothδ^(13)C andδ^(18)O in most specimens.We also observed a temporal lag betweenδ^(13)C andδ^(18)O in some specimens.This study demonstrates that intra-tooth stable isotope analysis is a promising approach to investigate seasonal dietary niche variation.However,large inter-individual variations inδ^(18)O at certain localities can be challenging to interpret.Future studies that expand the intra-tooth stable isotope surveys or include controlled feeding experiments will improve its application in ecological studies.展开更多
Meroplankton play a crucial role in both benthic and pelagic ecosystems.Existing quantitative research on estimating the quantities of meroplankton groups is both underrepresented and inaccurate.To investigate and eva...Meroplankton play a crucial role in both benthic and pelagic ecosystems.Existing quantitative research on estimating the quantities of meroplankton groups is both underrepresented and inaccurate.To investigate and evaluate the influence of varying mesh sizes(505 and 160μm)on the sampling efficiency of meroplankton,we conducted an examination using two commonly used plankton nets during the spring season in the Southern Yellow Sea(SYS).Our study revealed a total of 12 meroplankton groups,with 9 groups identified in the 505-μm mesh nets and 11 groups in the 160-μm mesh nets.The results demonstrated the superior collection efficiency of the 160-μm net compared to the 505-μm net across the majority of meroplankton groups.Furthermore,we focused on exploring the abundance,distribution patterns,and realized niches of meroplankton collected by the two mesh size nets,and observed that the distribution of meroplankton closely resembled the distribution of possible benthic adults in the SYS.Correlation analysis of the six dominant groups collected in the 160-μm mesh nets revealed that seawater temperature and salinity emerged as the key environmental factors driving variations in meroplankton abundance within the SYS.This study also found that a smaller mesh size net does not necessarily capture meroplankton more comprehensively.A comprehensive understanding of the ecological characteristics of meroplankton requires the combination of two types of nets for research.Our research significantly advances our understanding of the quantification,abundance,and distribution of meroplankton,serving as a valuable contribution to the broader landscape of detailed quantitative meroplankton studies.展开更多
基金supported by the National Natural Science Foundation of China(32271584 and 31600445)the Natural Science Basic Research Plan in Shaanxi Province of China(2020JM-286)+2 种基金the Fundamental Research Funds for the Central Universities(GK202103072 and GK202103073)the Key Research and Development Program of Shaanxi Province(2025SF-YBXM-514)Special Research Project in Philosophy and Social Sciences of Shaanxi Province(2022HZ1795).
文摘Predicting whether alien species will invade a native community is a key challenge in invasion ecology.One factor that may help predict invasion success is phylogenetic relatedness.Darwin proposed that closely related species tend to share similar niches,although this relationship may be influenced by various ecological and evolutionary factors.To test this,we classified alien Asteraceae species in China into three categories based on their invasion status and the extent of ecological damage:introduced,naturalized,and invasive.We then compared the genetic relationships and niche overlap between alien and native Asteraceae species.We found that invasive Asteraceae species are more closely related to native Asteraceae species than are introduced and naturalized species.However,alien Asteraceae species(including introduced,naturalized,and invasive species)exhibited relatively low niche overlap with native Asteraceae species.These findings suggest that the main premise underlying Darwin’s naturalization conundrum,namely,the universality of phylogenetic niche conservatism,may not hold true.Instead,our findings indicate that alien species are more likely to invade successfully when they are more closely related to native plants,exhibit less niche overlap,and maintain conservative niches during the invasion process.These findings provide new insights into the mechanisms of alien plant invasions,highlight the relationship between alien species invasions and native community vulnerability,and offer important insights into the development of effective biological invasion management strategies.
文摘[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in the Upper Yangtze River.This study initiated continuous monitoring of natural spawning habitats from February 2022 to assess these ecological changes.[Methods]Environmental DNA(eDNA)metabarcoding was employed to analyze fish species composition,biodiversity patterns,and niche parameters of dominant species.Water sampling followed the CEN/TS 19461 standard across five monitoring transects(ZT1-ZT5).[Results]The eDNA analysis detected 45 species of fish belonging to 38 genera,13 families,and 3 orders were detected through environmental DNA(eDNA)in this survey,including 10 species endemic to the upper reaches of the Yangtze River,such as Procypris rabaudi and Myxocyprinus asiaticus.The fish community was mainly composed of bottom-dwelling,settling ovum-producing,omnivorous fish.The variation ranges of the Chao1 index,ACE index,Shannon index,and Simpson index are 736~996,719~965,1.58~3.23,and 0.83~0.99,respectively,indicating that fish species in spawning sites are abundant and community distribution uniformity is high.All indexes are highest at ZT1 monitoring points.Cluster analysis showed that,at a certain similarity level,fish community types in spawning sites could be basically divided into two groups:ZT1,ZT3,and ZT5 clustered together,and ZT2 and ZT4 clustered together,indicating similar fish community habitats.There are 9 dominant fish species in typical deep pool habitats in the reserve,with niche widths(Bi)ranging from 1.13 to 3.87.The dominant fish species are broad and medium niche fish,such as Cyprinus carpio and Hemiculter tchangi,with the niche overlap index(Oik)of some dominant fish species reaching more than 0.95.This indicates fierce competition for resources among the fish in this spawning ground.[Conclusion]The Zhutuo spawning ground demonstrates high species richness with homogeneous community structure and intense resource competition.This study establishes an eDNA-based monitoring framework that enhances conventional survey method,providing critical baseline data for adaptive management under the fishing moratorium regime.
基金supported by the National Natural Science Foundation of China(No.32201304)the Fundamental Research Funds for the Central Universities(No.2412022QD026).
文摘Habitat fragmentation poses a significant threat to bird communities, especially those in open and semi-open ecosystems such as steppes. This study investigates how steppe birds adapt to and utilize fragmented habitats by combining niche modeling with ecological trait analysis. We conducted standardized point surveys to examine the habitat preferences of 32 bird species in Inner Mongolia, China, and quantified their habitat niche parameters using the Outlying Mean Index (OMI). Our results reveal distinct habitat preferences among species, with some thriving in intact environments while others are better adapted to fragmented areas. Grassland species showed high specialization along the fragmentation gradient, while others exhibited adaptability to varying levels of fragmentation. Using a Generalized Additive Model (GAM), we identified three key traits influencing habitat occupancy: hand-wing index, body mass, and range size. Specifically, species with medium hand-wing indices, moderate body mass, and larger range sizes were more likely to occupy heavily fragmented habitats. These findings provide empirical evidence on how habitat fragmentation affects bird species in steppe ecosystems. The study highlights the importance of functional traits in understanding avian responses to habitat fragmentation and offers a foundation for developing effective conservation strategies to preserve biodiversity in fragmented landscapes.
基金supported by the National Key Research&Development Project of China(Grant No.2016YFC0402209)and the China Scholarship Council.
文摘Accurate capture and presentation of the interactive feedback relationships among various objectives in multi-objective reservoir operation is essential for maximizing operational benefits.In this study,the niche theory of ecology was innovatively applied to the field of reservoir operation,and a novel state-relationship(S-R)measurement analysis method was developed for multi-objective reservoir operation.This method enables the study of interaction among multiple objectives.This method was used to investigate the relationship among the objectives of power generation,water supply,and ecological protection for cascade reservoir operation in the Wujiang River Basin in China.The results indicated that the ecological protection objective was the most competitive in acquiring and capturing resources like flow and water level,while the water supply objective was the weakest.Power generation competed most strongly with ecological protection and relatively weakly with water supply.These findings facilitate decision-making throughout the reservoir operation process in the region.The S-R method based on the niche theory is convenient,efficient,and intuitive,allowing for the quantification of feedback relationships among objectives without requiring the solution of the Pareto frontier of a multi-objective problem in advance.This method provides a novel and feasible idea for studying multi-objective interactions.
基金supported by the National Natural Science Foundation of China (No.32201304)the Fundamental Research Funds for the Central Universities (No.2412022QD026)。
文摘The transformation of natural habitats into human-modified landscapes has far-reaching consequences for species distribution and abundance.As species adapt to these changing environments,shifts in distribution patterns,niche dynamics,and interspecies interactions may occur,impacting biodiversity at multiple levels and potentially leading to ecosystem imbalances.This study aims to assess the impact of variations in vegetation composition and human disturbance on the distribution of sympatric breeding birds and to determine the extent of niche overlap or differentiation among these species.We conducted field surveys and collected data on bird distribution,vegetation composition,and level of human disturbance in eastern Inner Mongolian grasslands.We focused on the six most frequently co-occurring breeding birds,representing a mix of sparrows,larks,and corvids.Generalized Additive Models revealed varying responses of species occurrence along habitat gradients.Species like the Eurasian Skylark(Alauda arvensis),Mongolian Lark(Melanocorypha mongolica),and Asian Shorttoed Lark(Calandrella cheleensis),increased in larger and more connected habitats,while others,like the Tree Sparrow(Passer montanus),Eurasian Magpie(Pica pica),and Barn Swallow(Hirundo rustica),adapted to more fragmented habitats.Niche analysis indicated habitat generalists tended to occupy larger niches than grassland specialists.Substantial niche overlap was also found among the six co-occurring bird species.Conservation efforts should consider the specific needs of specialist species and strive to maintain or restore critical grassland habitats.Additionally,promoting sustainable agricultural practices that balance the needs of birds and human activities can contribute to the coexistence of generalist and specialist bird species in modified landscapes.
基金funded equally by grants from the National Natural Science Foundation of China(32322006 and 32100187)the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2024QZKK0200)+5 种基金by the Key Projects of the Joint Fund of the National Natural Science Foundation of China(U23A20149)the Key R&D Program of Yunnan Province(202103AF140005 and 202101BC070002)the Yunnan Provincial Science and Technology Talent and Platform Plan(202305AM070005)the Key Specialized Research and Development Breakthrough Program in Henan Province(232102110237)the Natural Science Foundation of Henan Province(242300421572)the Strategic Biological Resources Capacity Building Project of Chinese Academy of Sciences(KFJ-BRP-017-08).
文摘The formation of pantropical intercontinental disjunction(PID)in plants has generally been attributed to vicariance,boreotropical migration,and long-distance dispersal.However,this pattern has primarily been examined in herbs,shrubs,and trees,and less commonly studied in interlayer plant taxa.Here we examined evolutionary processes that resulted in the PID of a pantropical woody liana,Uncaria(Rubiaceae).We first constructed a comprehensive phylogeny by employing 73 plastid protein-coding sequences from 29 accessions of Uncaria(including 16 newly sequenced)from different continents.We then inferred divergence time,history and ecological niche evolution of this genus.Our results showed that Uncaria consisted of four well-supported clades that belonged to two geographically distinct lineages:the Asia-Oceania lineage and the Afro-Neotropical lineage.Biogeographic reconstruction showed this genus likely originated in Asia during the early Miocene(ca.19.03 Ma)and the Middle Miocene Climatic Optimum may have triggered the early diversification of Uncaria.Due to its recent origin and small seeds with long wings,wind or water-mediated long-distance dispersal may have contributed to the distribution of Uncaria in tropical Oceania(via stepping-stone dispersal)and tropical Africa and America(by transoceanic dispersal).Our findings also indicate that diversification of Uncaria was primarily driven by ecological niche divergence,particularly climatic factors.Our study emphasizes the dual role of climatic niche divergence and long-distance dispersal in shaping the PID of Uncaria,providing references for many other extant lineages with similar distributions.
基金supported by Fundamental Research Funds for the Central Universities(ZYN2024075)Chengdu Science and Technology Bureau Technology Innovation R&D Project(2024-YF05-02236-SN)the Applied Basic Research Project of the Sichuan Science Technology Department(2021YJ0256).Peer review information。
文摘Background:The traditional Chinese medicine compound Sancao decoction(SCD)is a folk prescription for regulating immunity.It is composed of 8 Chinese herbal medicines,such as Prunellae Spica(Xiakucao),Houttuyniae Herba(Yuxingcao),Lysimachiae Herba(Jinqiancao)and so on.In cancer,the interleukin-6(IL-6)/the signal transducer and the activator of transcription 3(STAT3)pathway directly promotes the proliferation,survival and angiogenesis of cancer cells,and arginase-1(ARG-1)is a key enzyme for myeloid-derived suppressor cells(MDSCs)to exert immunosuppressive function.It is not clear whether SCD regulates the expression of ARG-1 in MDSCs through the IL-6/STAT3 pathway.Therefore,we explored the effect and mechanism of SCD on lung metastasis of breast cancer.Methods:The components in SCD have been analyzed by HPLC-MS.A spontaneous metastasis model of breast cancer was established by injecting 4T1 cells into the mammary fat pad of BALB/c mice.Pre-metastatic niche(PMN)formation and the role of SCD on PMN were evaluated by lung metastasis nodules,lung pathology tests and immunofluorescence for 2–4 weeks.Serum tests and hematoxylin-eosin staining(H&E)were used to evaluate the side effects of cisplatin.Western blot and ELISA were used to detect proteins and cytokines of the STAT3 signaling pathway in mouse lung tissue.Results:Compared with SCD or cisplatin treatment alone,SCD/cisplatin(CP)synergistic administration not only significantly inhibited orthotropic breast tumor growth,but also reduced lung metastasis and alleviated the hepatorenal toxicity induced by CP in vivo.Remarkably,the combination effectively inhibited PMN formation and the accumulation of MDSCs in the lung PMN,accompanied by the significant infiltration of CD4+T and CD8+T-lymphocytes in the lung PMN and spleen.In addition,the SCD/CP combination downregulated protein expression levels of STAT3,p-STAT3,IL-6 and ARG-1 in the lung PMN of breast cancer mice.Conclusion:The synergistic effect of SCD and cisplatin inhibited MDSCs aggregation and the immunosuppressive function of pulmonary PMN,thereby remodeling the immunosuppressive tumor microenvironment and enhancing anti-tumor immunity,leading to remission of orthotopic breast cancer and lung metastases and amelioration of cisplatin-induced liver and kidney toxicity.
文摘Subterranean environments are buffered from external climatic fluctuations due to the absence of light and a delayed thermal response to surface conditions(Mammola 2019).Terrestrial salamanders are often found in subterranean habitats,but few studies have assessed the influence of climatic effects on their long-term spatial distribution and niche breadth.In this study,we investigated the variability over 29 consecutive years of the spatial niche in a terrestrial salamander population inhabiting an artificial subterranean habitat.We hypothesized that juvenile salamanders,which are typically active near cave entrances and more exposed to climatic variability and dehydration(Peterman et al.2013),would exhibit an earlier and more variable behavioral adaptation to increasing external temperatures compared to adults.
文摘Two widespread bird species in Sri Lanka’s dry zone,Pycnonotus cafer(Red-vented Bulbul,RVBB)and Pycnonotus luteolus(White-browed Bulbul,WBBB),were studied to understand their foraging dynamics and ecology.The research was conducted from October 2022 to February 2023 in Mihintale Sanctuary(80.30′11.24″E,8.21′04.63″N)and the Faculty of Applied Sciences,Rajarata University of Sri Lanka(80.502206″E,8.353090″N).Data were obtained through focal sampling,opportunistic observations,and mist netting.Both species predominantly foraged on twigs,using gleaning as the dominant food-handling technique.RVBB foraged mostly at the canopy level,while WBBB foraged primarily at the sub-canopy level.Fruits constituted the major food type for both species.RVBB and WBBB utilized 10 and 7 plant species,respectively,with Grewia helicterifolia being the primary foraging plant.Minimal foraging was observed on Croton sp.(RVBB)and Hugonia mistax(WBBB).The correlation between nutritional components and the consumption of both species revealed a preference for foods with lower protein,higher fat,and ash content.There was no linear correlation between gape width and fruit size(r=-0.21,P=0.69)for both species.The standardized dietary niche breadth indicated both species are specialists,with a high pairwise dietary niche overlap(0.9854).These findings highlight the niche-specific foraging adaptations of RVBB and WBBB within Mihintale,emphasizing their distinct strategies in utilizing plant species,fruit sizes,and foraging heights.Understanding such ecological dynamics is essential for habitat conservation efforts and ensuring the availability of key foraging resources for these species in the dry zone.
基金the National Nature Science Foundation of China(No.32360052)the Department of Science and Technology Foundation of Guizhou Province,China[No.2017(5742)]。
文摘Urbanization and industrialization have heightened the risk of groundwater contamination in karst regions,threatening the safety of petrifying spring water.Petrifying spring-moss systems serve as critical interfaces for groundwater-surface water interaction,retaining potentially toxic elements(PTEs)and improving water quality in karst ecosystems.However,it remains uncertain whether the niche differentiation among moss species influences their capacity for the retention of PTEs.This study examines the petrifying spring-moss system in Tongren Grand Canyon,Guizhou Province,a typical karst region in southwestern China.Four dominant moss species with distinct ecological niches were selected for this study.Inductively coupled plasma mass spectrometry(ICPMS)was used to quantify PTEs in the petrifying springmoss systems and their associated water flows.Ecological niche analysis was integrated to evaluate the PTEs enrichment efficiencies of different petrifying spring-moss systems.The results identified Fissidens grandifrons Brid.,Hydrogonium majusculum(C.Muell.)Chen,Brachythecium curtum(Lindb.)Limpr.,and Cratoneuron filicinum(Hedw.)Spruc.var.filicinum as representative species of distinct ecological niches.After filtration through the petrifying spring-moss systems,the concentrations of PTEs in the water were significantly reduced(P<0.05).The retention capacities of moss species varied significantly across ecological niches and were ranked as follows:C.filicinum var.filicinum>B.curtum>F.grandifrons>H.majusculum.This study demonstrates that karst petrifying spring-moss systems efficiently intercept PTEs in groundwater and reveals,from a niche theory angle,the link between moss niche differentiation and their retention efficiency,which offers innovative strategies for ecological remediation of PTEs pollution in global karst groundwater systems.
基金founded by National Natural Science Foundation of China (Grant Number:32370545)Marine Protected Area Administration of Sansha City (Monitoring seabird spatial-temporal dynamic project in Sansha City)Science and Technology Planning Projects of Guangdong Province, Grant Number:2021B1212110002
文摘Studying coexistence mechanisms is practically important for understanding and conserving marine biodiversity and community structure. Tropical marine ecosystems may exhibit higher competition between top predators due to generally low primary productivity and pronounced seasonal fluctuation in food availability. Consequentially, niche segregation in sympatric breeding seabirds is expected to occur as a mechanism to maintain species coexistence. However, a single-dimensional study on seabird niche segregation might result in unclear niche overlap. Here, we investigated multi-dimensional niche segregation of tropical seabirds during field expeditions to the Xisha Archipelago, China, in 2023. We reconfirmed the breeding status of six species of terns and noddy, and further revealed the multi-dimensional niche segregation among Black-naped (Sterna sumatrana), Bridled (Onychoprion anaethetus) and Roseate (Sterna dougallii) Terns. Spatially, these three species utilized nest sites that differentiated by vegetation and distance to sea. Temporally, Black-naped Terns bred earlier and for a longer period, while Bridled and Roseate Terns had more restricted breeding seasons. Furthermore, the daily foraging activity patterns of these species also differed, with Bridled Terns potentially having a longer foraging time at noon. In terms of diet, Bridled Terns were opportunists that fed on fishes, squids and insects, such as migratory fruit-piercing moths, while Roseate Terns were primarily piscivorous, especially feeding on Exocoetidae (flying fishes). Seabirds play a crucial role in marine ecosystems and are globally threatened. Our findings shed light on the complex mechanisms facilitating the coexistence of sympatric seabird species in China. Further research is needed to examine other ecological interactions and to develop effective conservation strategies for protecting these valuable seabird populations.
基金financial support from CNPq/Peld CRSC,Fapemig,CAPES,Anglo American,and Vale.
文摘Anthropogenic disturbances are causing significant impacts on plant distribution worldwide,and many of these effects are driven by changes in the recruitment patterns of plant species.Global warming and land-use change are two major disturbances leading to changes in germination strategies by changing both soil temperature regimes and light quality reaching the seeds due to soil disturbance.Investigating the range,overlap,and redundancy of niche germination of co-occurring plant species allows us to understand whether endemic species are threatened either by native non-endemic or by alien species,especially in an ecosystem of restricted distribution such as the campo rupestre.Employing a systematic review,this study aimed to evaluate the effect of temperature increase and seed burial on the germination of endemic and non-endemic species in the campo rupestre in Brazil.We performed a metaanalysis using increased temperature and darkness as proxies for the impact of disturbance on germination patterns.In this context,we hypothesized that:increased temperature and darkness negatively influence the germination of native species and positively influence the germination of alien species in the campo rupestre.Specifically,we expect the negative effect to be more pronounced in endemic species than in native non-endemic species.Moreover,we intend to describe the role of seed size in the germination of native and alien species from campo rupestre in the context of increased temperature and darkness.Our analysis showed that increased temperature influenced the germination of alien species by ca.55%,while it did not influence the germination of endemic or native non-endemic species.Furthermore,the germination of alien species under higher temperatures was promoted by increasing seed size.Darkness negatively influenced seed germination of native species,independent of their distribution.Moreover,under darkness conditions,the germination of endemic seeds decreased with seed size.Through their direct effects on germination strategies,we conclude that warming temperatures and land-use change can lead to a long-term displacement of endemic species by native non-endemic and alien species in campo rupestre,thus compromising ecosystem services and conservation of these fragile physiognomies in the near future.
基金funded by the National Science Foundation for Young Scientists of China(No.32001327)the National Key Research and Development Program of China(No.2021YFD2200304-2).
文摘As global warming persistently alters and rapidly reshapes landscapes and habitats, conventional species distribution models relying solely on maintaining static conditions within the current climate are likely to falter, particularly at the genus level. Hence, we hypothesize that climate change will differentially affect ecological niches of the same genus species with various latitudinal positioning and local topography, and the high-latitude species may experience greater niche contraction than low-latitude species, and that mountainous regions with high elevational variability may serve as critical climate refugia. Herein, we simulate niche alterations and integrate an ensemble model(EM) strategy, taking into account species dispersal limitations factors(topography, soil, and ultraviolet), to construct a comprehensive habitat suitability(CHS) model for assessing the future vulnerability of the Betula genus, most of which are timber species in China. Our findings reveal that the niche spatial(geographic distribution) of most species(62%) within the Betula genus will undergo a gradual decline under climate change, supporting our hypothesis of latitudinal differentiation in climate vulnerability. Intriguingly, the projected high-latitude niche reduction within the genus cannot be counterbalanced by the anticipated niche expansion of closely related species in low-latitude regions, even considering the evident latitudinal gradient distribution of species. Nonetheless, the niche spatial of six Betula species in southwestern China remains stable or expands under warming scenarios, strongly supporting our secondary hypothesis about topographic buffering effects, which probably means the unique topography(i.e., the largest elevation difference) of this region may serve as a sanctuary for preserving Betula genetic diversity. Our results underscore the uncertain nature of pre-existing niche systems at the genus level under climate change, emphasizing the need for diligent resource management and conservation planning for vulnerable timber species.
基金Natural Science Foundation Project of Hebei Provincial Science and Technology Department(G2023415001)Humanities and Social Sciences Research Project of Colleges and Universities in Hebei Province(SD2021084)The 2025 Hebei Province Social Science Development Research Project titled“Practical Research on Hebei Province’s Undertaking of the Elderly Care Service Industry from Beijing and Tianjin under the Collaborative Development of the Beijing-Tianjin-Hebei Region”。
文摘The expansion of the scale of the elderly care industry,the acquisition of market share,and the seizure of high profits depend on the consistency between the ecological niche of the elderly care industry and the actual resource and environmental conditions.Based on the situation theory of ecological niche,this paper expands the factor of“energy”and represents the three dimensions of“state,”“potential,”and“energy”from three aspects:market niche,technology niche,and resource niche.Taking 220 listed companies as samples,this paper improves the traditional catastrophe progression evaluation model and uses structural equation modeling to test the validity of the indicator system,thereby conducting evaluation research on the ecological niche of the elderly care industry.From the results of niche potential energy measurement,the three dimensions of market niche,resource niche,and technology niche are unevenly developed,reflecting the lack of competitiveness of the elderly care industry.
基金Supported by the National Key Scientific Research Project(No.2018YFC1508200)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX 23_0714)+1 种基金the China Scholarship Council(No.202206710066)the Construction Project of Wenzhou Hydrology High quality Development Pilot Zone(No.WZSW-GZLFZXXQ-202105)。
文摘To investigate the dominant species and interspecific association in the phytoplankton community of the Feiyun River basin in Zhejiang Province,East China,the main stream and the Shanxi Zhaoshandu Reservoir in the downstream were chosen as the study area,for which 22 sampling sites were designated.Sampling was conducted in September 2021,January,May,and July 2022.Phytoplankton species were identified from both quantitative samples and in-vivo observations.Phytoplankton was quantified by direct counting.Results show that there were 98 species belonging to 6 phyla and 78 genera.In addition,to clarify the niches of the dominant phytoplankton species and their interspecific association,the dominance index was calculated,and a comprehensive analysis was conducted including niche width,niche overlap value,ecological response rate,overall association,chi-square test,and the stability.The phytoplankton community exhibited characteristics of a Cyanobacteria-Chlorophyta-Diatom type community,showing higher diversity in spring and lower diversity in summer.Among 11 dominants phytoplankton species from 3 phyla,both frequency and dominance degree varied seasonally,of which Microcystis sp.was the dominant species in Spring,Autumn,and Winter.The niche widths of the dominant species ranged from 0.234 to 0.933,and were categorized into three groups.The niche overlap values of the 11 dominant species ranged from 0.359 to 0.959,exhibiting significant seasonal differences-highest in winter followed by autumn,spring,and summer in turn.The overall correlation among dominant species in all four seasons revealed a non-significant negative association,resulting in an unstable community structure.A significant portion(84.2%)of species pairs displayed positive associations,suggesting a successional pattern where Diatoms dominated while other dominant species shared resources and space.Despite this pattern,stability measurements indicated that the dominant species community remained unstable.Therefore,careful monitoring is recommended for potential water environment issues arising from abnormal proliferation of dominant species in the watershed during winter.This research built a theoretical foundation with a data support to the early warning of eutrophication and provided a reference for water resources management in similar watersheds along the eastern coast of China.
文摘In recent years,there has been considerable exploration into methods aimed at enhancing the regenerative capacity of transplanted and/or tissue-resident cells.Biomaterials,in particular,have garnered significant interest for their potential to serve as natural scaffolds for cells.In this editorial,we provide commentary on the study by Wang et al,in a recently published issue of World J Stem Cells,which investigates the use of a decellularized xenogeneic extracellular matrix(ECM)derived from antler stem cells for repairing osteochondral defects in rat knee joints.Our focus lies specifically on the crucial role of biological scaffolds as a strategy for augmenting stem cell potential and regenerative capabilities,thanks to the establishment of a favorable microenvironment(niche).Stem cell differen-tiation heavily depends on exposure to intrinsic properties of the ECM,including its chemical and protein composition,as well as the mechanical forces it can generate.Collectively,these physicochemical cues contribute to a bio-instructive signaling environment that offers tissue-specific guidance for achieving effective repair and regeneration.The interest in mechanobiology,often conceptualized as a form of“structural memory”,is steadily gaining more validation and momen-tum,especially in light of findings such as these.
基金supported by the Leakey Foundation,Sigma Xi Grants in Aid of Research[G2017031588721189]the National Science Fountation-Inter University Training in Continental Scale Ecology(EF-1137336)through a research-in-residence program at the University of Utah,the Interdepartmental Doctoral Program in Anthropological Sciences of Stony Brook University+2 种基金the Turkana Basin Institutesupported by the French government in the framework of the University of Bordeaux’s IdEx“Investments for the Future”program/GPR“Human Past.”partially supported by the Center for Climate Life and the Vetlesen Foundation while at Lamont Doherty Earth Observatory。
文摘How animals respond to seasonal resource availability has profound implications for their dietary flexibility and realized ecological niches.We sought to understand seasonal dietary niche partitioning in extant African suids using intra-tooth stable isotope analysis of enamel.We collected enamel samples from canines of red river hogs/bushpigs(Potamochoerus spp.)and third molars of warthogs(Phacochoerus spp.)in 3 different regions of central and eastern Africa.We analyzed multiple samples from each tooth and used variations in stable carbon and oxygen isotope ratios(δ^(13)C andδ^(18)O)and covariances between them to infer seasonal dietary changes.We found that most Phacochoerus display C_(4)-dominated diets,while most Potamochoerus display C_(3)-dominated diets.Phacochoerus and Potamochoerus that co-occur in the same region display no overlap in intra-toothδ^(13)C,which suggests dietary niche partitioning.They also show divergingδ^(13)C values as the dry seasons progress and convergingδ^(13)C values during the peak of the rainy seasons,which suggests a greater dietary niche separation during the dry seasons when resources are scarce than during the rainy season.We found statistically significant cross-correlations between intra-toothδ^(13)C andδ^(18)O in most specimens.We also observed a temporal lag betweenδ^(13)C andδ^(18)O in some specimens.This study demonstrates that intra-tooth stable isotope analysis is a promising approach to investigate seasonal dietary niche variation.However,large inter-individual variations inδ^(18)O at certain localities can be challenging to interpret.Future studies that expand the intra-tooth stable isotope surveys or include controlled feeding experiments will improve its application in ecological studies.
基金Supported by the Laoshan Laboratory(Nos.LSKJ 202203700,LSKJ 202203704,LSKJ 202204005)the National Natural Science Foundation of China(NSFC)(Nos.42076166,42130411)the NSFC Ship Time Sharing Project(No.42149901)。
文摘Meroplankton play a crucial role in both benthic and pelagic ecosystems.Existing quantitative research on estimating the quantities of meroplankton groups is both underrepresented and inaccurate.To investigate and evaluate the influence of varying mesh sizes(505 and 160μm)on the sampling efficiency of meroplankton,we conducted an examination using two commonly used plankton nets during the spring season in the Southern Yellow Sea(SYS).Our study revealed a total of 12 meroplankton groups,with 9 groups identified in the 505-μm mesh nets and 11 groups in the 160-μm mesh nets.The results demonstrated the superior collection efficiency of the 160-μm net compared to the 505-μm net across the majority of meroplankton groups.Furthermore,we focused on exploring the abundance,distribution patterns,and realized niches of meroplankton collected by the two mesh size nets,and observed that the distribution of meroplankton closely resembled the distribution of possible benthic adults in the SYS.Correlation analysis of the six dominant groups collected in the 160-μm mesh nets revealed that seawater temperature and salinity emerged as the key environmental factors driving variations in meroplankton abundance within the SYS.This study also found that a smaller mesh size net does not necessarily capture meroplankton more comprehensively.A comprehensive understanding of the ecological characteristics of meroplankton requires the combination of two types of nets for research.Our research significantly advances our understanding of the quantification,abundance,and distribution of meroplankton,serving as a valuable contribution to the broader landscape of detailed quantitative meroplankton studies.
