In metropolitan regions, the change in the strength of "flows" between a core city and surrounding cities re-flects the range of the core city's influence, while the gravity between core city and other c...In metropolitan regions, the change in the strength of "flows" between a core city and surrounding cities re-flects the range of the core city's influence, while the gravity between core city and other cities reflects the strength of potential relation between them. This article firstly attempts to delimit the boundary of metropolitan regions with the two dimensions measure combining "flows" and gravitation. The former is measured through the flow of people be-tween the core city and surrounding cities, and the latter is measured through both population and gross domestic products (GDP) of the core city and surrounding cities. The hierarchy of the cities within a metropolitan region is classified in order to emphasize the roles of the cities belonging to the metropolitan regions, different from the general way through population scale and administrative level, and is typical in China. This paper uses the Shanghai metropolitan region as a research case, determining boundary of this metropolitan region clearly and classifying hierarchy of the cities within the region. The final results are significantly different to previous work, even overthrowing the traditional system of urban hierarchy partly. It is helpful to highlight the function of cities in organizing the regional economy, the level structure of metropolitan regions, and each city's relative importance in a metropolitan region, which can be taken as scientific basis for planning integrated regions or urban systems.展开更多
Accurate species identification is a key component of biodiversity research.DNA barcoding is an effective molecular method used for fish species identification.We aimed to study the DNA barcoding of fish in Zhoushan c...Accurate species identification is a key component of biodiversity research.DNA barcoding is an effective molecular method used for fish species identification.We aimed to study the DNA barcoding of fish in Zhoushan coastal waters,explore the differences and applicability of two gene fragments(12S rRNA and COI)of DNA barcoding in fish species identification,and established a comprehensive fish barcoding reference database.Two hundred and eighty-seven captured fish samples from Zhoushan coastal waters were identified using morphological characteristics and DNA barcoding.A total of 26412S rRNA sequences(belonging to eight orders,31 families,55 genera,and 66 species)and 188 COI sequences(belonging to seven orders,30 families,48 genera,and 58 species)were obtained.The lengths of the 12S rRNA sequences ranged from 165 to 178 bp,and the guanine-cytosine(GC)content was 45.37%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.10%and 26.66%,respectively.The length of the COI sequence ranged 574–655 bp,and the content of GC was 45.97%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.16%and 27.45%,respectively.The minimum interspecific genetic distances of 12S rRNA and COI(1.23%and 1.86%)were both greater than their maximum intraspecific genetic distances(2.42%and 8.66%).Three molecular analyses(NJ tree,ABGD,and GMYC)were performed to accurately identify and delineate species.Clustering errors occurred when the 12S rRNA sequences were delimited using the NJ tree method,and the delimitation results of ABGD and GMYC are consistent with the final species identification results.Our results demonstrate that DNA barcoding based on 12S rRNA and COI can be used as an effective tool for fish species identification,and 12S rRNA has good application prospects in the environmental DNA(eDNA)metabarcoding of marine fish.展开更多
Much confusion has surrounded the taxonomy of the Collared Scops Owl(Otus bakkamoena)complex,distributed widely across tropical and subtropical Asia.Often divided into three species,modern taxonomies disagree on its t...Much confusion has surrounded the taxonomy of the Collared Scops Owl(Otus bakkamoena)complex,distributed widely across tropical and subtropical Asia.Often divided into three species,modern taxonomies disagree on its treatment,as a lack of deep mitochondrial DNA divergence is seemingly in contrast with patterns of vocal differentiation.Analysing a dataset of territorial calls of 122 individuals across Asia,we identified a vocal leapfrog pattern in which owl populations at the eastern and western ends of the distribution sound more similar to each other but are separated by different-sounding populations in between.The boundaries between vocal types are not congruent with traditional species boundaries.Our data allow for a re-drawing of species boundaries and reveal that Collared Scops Owls follow a biogeographic pattern rare in Southeast Asian birds.However,this pattern is shared with several other owl complexes in that peninsular Malaysian populations form part of a continental Asian species centred further north in Southeast Asia rather than forming part of a Sundaic species centred in the adjacent Indonesian Archipelago.展开更多
The seismic hazard of research area is evaluated by probabilistic analysis method for three different seismic statis-tical zone scenarios. The influence of uncertainty in seismic statistical zone delimiting on the eva...The seismic hazard of research area is evaluated by probabilistic analysis method for three different seismic statis-tical zone scenarios. The influence of uncertainty in seismic statistical zone delimiting on the evaluation result is discussed too. It can be seen that for those local sites along zone's border or within areas with vast change of upper bound magnitude among different scenarios the influence on seismic hazard result should not be neglected.展开更多
Geological anomaly is a geological body or geological body combination different from its surroundings in composition, structure, or genetic sequence. If there is a value (value interval ) that works as a valve repres...Geological anomaly is a geological body or geological body combination different from its surroundings in composition, structure, or genetic sequence. If there is a value (value interval ) that works as a valve representing the background field, exceeding or lower than the valve value,it is called a geological anomaly. Geological anomalies can be divided into high geological anomaly and low geological anomaly .The former shows the area that is more complex in composition, Structure or genetic sequence than its surroundings; while the latter just gives an opposite indication, i. e. much simpler. According to their distribution and delimitation markers, geological anomalies can be classified into (1)global geological anomaly; (2)regional geological anomaly; (3) local geological anomaly; (4) minor geological anomaly and (5)micro-geological anomaly .The methods for delimiting geological anomalies include (1)crustal elevation-subsidence coefficieat (G value ) determination; (2) geological complex coefficient (C value ) determination; (3) entropy (H value ) determination; (4) geological similarity coefficient (S value ) determination and (5 ) geological correlation coefficient (R value ) determination. As the result of the movements of Eurasian, Pacific and Indian Plates, the Chinese geological anomalies, including 11 regional ones and 32 main local ones, most Paleozoic in age, are distributed in strip on the margin or the outer and inner folded zones in the east and west arcs of the block symmetric arc tectonic system (BSATS), which controls the distribution of various minerals in China. Thus, geological anomaly theory is of great significance in searching for large, super-large and very large ore deposits.展开更多
Objective:To examine and study the morphology,epidemiology,and molecular phylogeny of Anisakis larvae in blue mackerel[Scomber australasicus(Cuvier,1832)]and Indian mackerel[Rastrelliger kanagurta(Cuvier,1816)]using l...Objective:To examine and study the morphology,epidemiology,and molecular phylogeny of Anisakis larvae in blue mackerel[Scomber australasicus(Cuvier,1832)]and Indian mackerel[Rastrelliger kanagurta(Cuvier,1816)]using light microscope,scanning electron microscope,molecular phylogeny,and species delimitation methods for confirmation and investigation of Anisakis species and their evolutionary relationship.Methods:A total of 90 fish(45 per species)were purchased from a department store in Chiang Mai,Thailand.Anisakis samples were investigated for morphological characteristics using light and scanning electron microscopes.Molecular phylogeny and species delimitation methods based on the cox2 gene were performed.Results:The prevalence,mean intensity(Mean±SEM),and mean abundance of Anisakis larvae(Mean±SEM)in blue mackerel were 77.78%,6.74±1.320,and 5.24±1.107,respectively,and in Indian mackerel,these values were 13.33%,2.50±0.764,and 0.33±0.159,respectively.Scanning electron microscopy showed the detail of morphological characteristics and provided the different shapes of mucron and excretory pores in Anisakis larvae congruent with the phylogenetic tree.The species tree was congruent with the phylogenetic tree.Conclusions:The prevalence,mean intensity,and mean abundance of Anisakis larvae were higher in blue mackerel.To the best of our knowledge,this is the first time that Anisakis pegreffii was found in blue mackerel in Thailand.The phylogenetic tree also supported the morphological data of Anisakis larvae.However,species delimitation based on cox2 revealed 1-3 possible cryptic species in this genus.Anisakis spp.contamination of fish products is unpleasant and a health concern considering human infection with larvae(anisakiasis)arises.展开更多
The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary rel...The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal.展开更多
Sparids are of considerable economic importance in marine fishery and aquaculture in China, and the species diversity of this group is considered relatively high. However, the accurate species identification and delim...Sparids are of considerable economic importance in marine fishery and aquaculture in China, and the species diversity of this group is considered relatively high. However, the accurate species identification and delimitation of sparids in China remain unaddressed. In this study, we used mitochondrial cytochrome oxidase subunit ?(COI) and 16S ribosomal RNA(16S) genes to conduct DNA barcoding and species delimitation in eleven sparid species from the coastal waters of China. Based on Kimura-2 parameter genetic distances, the mean intraspecific/interspecific variation for COI and 16S were calculated as 0.004/0.152 and 0.002/0.072, respectively. All the conspecific individuals formed monophyletic clusters in neighbour-joining trees of both markers. An obvious barcoding gap was detected for each species, and a common genetic threshold of 1.3% sequence divergence was defined for species delimitation in both markers. Although the sequence variation of 16S was generally lower than that of COI, the results indicated that sparid species could be ef fectively and accurately identified and delimited by COI as well as 16S. Thus, we propose that the COI gene serve as the standard DNA barcode for sparids, and that the 16S gene could also be an ideal candidate barcode. Moreover, each of the six sparid species( Argyrops spinifer, Rhabdosargus sarba, Dentex hypselosomus, Acanthopagrus latus, Acanthopagrus australis and Acanthopagrus berda) showed high intraspecific divergence(>1.3% genetic threshold) with the remarkable geographic lineages in the Indo-West Pacific oceans, which supported that potential unrecognized cryptic species were in them. The potential cryptic diversity revealed here might be primarily attributed to the allopatric divergences caused by the long-term geographic isolation between the Indian and West Pacific oceans or between the opposite sides of the Indian Ocean. The results further suggest that a revision of taxonomic status of these species is required, followed by development of a biodiversity conservation strategy.展开更多
Codium, one of the largest marine green algal genera, is difficult to delimit species boundary accurately based on morphological identification only. DNA barcoding is a powerful tool for discriminating species of seaw...Codium, one of the largest marine green algal genera, is difficult to delimit species boundary accurately based on morphological identification only. DNA barcoding is a powerful tool for discriminating species of seaweeds. The plastid elongation factor TU （tufA） is considered as maker to perform DNA barcoding of green algal species than rbcL gene due to universality and rapid evolution rate. We conducted DNA barcoding application to Codium specimens from the Jeju Island, Korea to overcome the limit of morphological identification and to confirm the species diversity. As a result of applying tufA marker, we newly generated fifty-five tufA barcodes to resolve eight species. TufA marker exhibited 6.1%–21.8% interspecific divergences, wider than the gap of rbcL exon 1, 3.5%–11.5%. Molecular analysis of rbcL exon 1 sequences of Codium revealed eight distinct species like tufA analysis separated in five phylogenetic groups. DNA barcoding of the genus Codium using tufA marker is more helpful to overcome the limit of morphological identification, and this is more potential to reveal cryptic species and to resolve the relationships among subspecies than rbcL analysis alone. The complement of tufA barcoding and rbcL analyses including morphology for the genus Codium in the northwestern Pacific will give much more reliable achievement for discovering species diversity and resolving the phylogenetic relationships.展开更多
Delimiting species requires multiple sources of evidence.Here,we delimited two varieties of Halenia elliptica(Gentianaceae)using several lines of evidence,including morphological traits and mating system in a sympatri...Delimiting species requires multiple sources of evidence.Here,we delimited two varieties of Halenia elliptica(Gentianaceae)using several lines of evidence,including morphological traits and mating system in a sympatric population,phylogenetic relationships based on nrITS and cpDNA(rpl16)data,and complete chloroplast genome sequences.Comparative analysis of 21 morphological traits clearly separates the two varieties of H.elliptica.Examination of the flowering process and pollination treatments indicate that H.elliptica var.grandiflora produces seeds via outcrossing,whereas H.elliptica var.elliptica produces seeds via mixed mating.Furthermore,hand-pollinated hybridization of the two varieties produced no seeds.Observations of pollinators showed that when bees began a pollination bout on H.elliptica var.grandiflora they preferred to continue pollinating this variety;however,when they began a pollination bout on H.elliptica var.elliptica,they showed no preference for either variety.Phylogenetic analysis confirmed the monophyly of H.elliptica,which was further divided into two monophyletic clades corresponding to the two varieties.A large number of variants from the chloroplast genomes reflected remarkable genetic dissimilarities between the two varieties of H.elliptica.We recommend that the two varieties of H.elliptica should be revised as two species(H.elliptica and H.grandiflora).Our findings indicate that H.elliptica varieties may have split into two separate species due to a shift in mating system,changes in flowering phenology and/or post-pollination reproductive isolation.展开更多
This paper makes a summary of status of delimitation of seismic zones and belts of China firstly in aspects of studying history, purpose, usage, delimiting principles, various presenting forms and main specialties. Th...This paper makes a summary of status of delimitation of seismic zones and belts of China firstly in aspects of studying history, purpose, usage, delimiting principles, various presenting forms and main specialties. Then the viewpoints are emphasized, making geographical divisions by seismicity is just the most important purpose of delimiting seismic belts and the concept of seismic belt is also quite different from that of seismic statistical zone used in CPSHA method. The concept of seismic statistical zone and its history of evolvement are introduced too. Large differences between these rwo concepts exist separately in their statistical property, actual meaning, gradation, required scale, and property of refusing to overlap each other, aim and usage of delimitation. But in current engineering practice, these two concepts are confused. On the one hand, it causes no fit theory for delimiting seismic statistical zone in PSHA to be set up; on the other hand, researches about delimitation of seismic belts with purposes of seismicity zoning and studying on structural environment, mechanism of earthquake generating also pause to go ahead. Major conclusions are given in the end of this paper, that seismic statistical zone bases on the result of seismic belt delimiting, it only arises in and can be used in the especial PSHA method of China with considering spatially and temporally inhomogeneous seismic activities, and its concept should be clearly differentiated from the concept of seismic belt.展开更多
The central value 23°26′17″ of the Tropic of Cancer is used for delimiting the standard position of the Tropic of Cancer as well as countries, regions and cities which the Tropic of Cancer traverses. It is conf...The central value 23°26′17″ of the Tropic of Cancer is used for delimiting the standard position of the Tropic of Cancer as well as countries, regions and cities which the Tropic of Cancer traverses. It is confirmed that the Tropic of Cancer runs through 19 countries and regions in the world, and it traverses Yunnan, Guangxi, Guangdong, Fujian （sea area） and Taiwan provinces in China. At the same time, regions which the Tropic of Cancer traverses are divided into three regions, namely the extensive Tropic of Cancer region, the Tropic of Cancer region and the core area of the Tropic of Cancer. The series of delimitation and division aims to explore ways of sustainable development under the restriction of resources and environment and build collaborative development areas of the Tropic of Cancer at all leaves, especially setting up the collaborative de- velopment zone of the Tropic of Cancer in China and international collaborative development circle of the Tropic of Cancer.展开更多
To solve some unreasonable problems in the acceptance process of the delimitation project of grain production functional zones,the acceptance results of grain production functional zones in Fangzi District,Weifang Cit...To solve some unreasonable problems in the acceptance process of the delimitation project of grain production functional zones,the acceptance results of grain production functional zones in Fangzi District,Weifang City were elaborated from the aspects of the third party organization,inspectors,expert group,acceptance criteria,acceptance method,acceptance contents,etc.,and the overall performance of the project was reviewed.The problems that need to be rectified during the implementation of the project were put forward,and the irrationality of the acceptance and the places that need to be improved were pointed out,which would provide a better guiding value for the delimitation of grain production functional zone and the acceptance and performance evaluation of similar projects.展开更多
On the Pacific coast of Russia implementation of the methodology of the integrated nature management has a number of peculiarities. On the one hand, these districts are characterized by severe hydrometeorological cond...On the Pacific coast of Russia implementation of the methodology of the integrated nature management has a number of peculiarities. On the one hand, these districts are characterized by severe hydrometeorological conditions. On the other hand, Russia has no applicable legislation on coastal issues. Thus, to prepare informational, theoretical and methodical bases for organization of sustained nature management in coastal zones of the Russian Federation, we developed hierarchy structure of delimitation of coastal areas and recommendations for their development on the basis of nature resource and social-economic zoning. Zoning of the Russian Far East is suggested to include two major directions： （1） planning of sustainable development of the region and （2） solving contradictions between fisheries and productions of oil and gas in the coastal zones.展开更多
Issues concerning on the continental shelf and in the exclusive economic zone between Turkey and the Greek Cypriot Administration (GCA) have been more controversial. This study answers the following questions:(a) What...Issues concerning on the continental shelf and in the exclusive economic zone between Turkey and the Greek Cypriot Administration (GCA) have been more controversial. This study answers the following questions:(a) What is the main arguments of the Parties?(b) How the exclusive economic zone could be declared?(c) Does median line applicable to the delimitation law without taken the related circumstances in the Eastern Mediterranean?(d) Can any maps on claimed exclusive economic zone borders publish without maritime boundary delimitation agreements, officially? The main intent of the study is to evaluate the different perspectives of the Parties on maritime delimitation and to evaluate the boundaries of the exclusive economic zone bounded by the European Union on the European Asia and Europe Africa Interconnected Cable Network Projects maps in the Eastern Mediterranean.展开更多
The United Nations Convention on the Law of the Sea entitled the coastal States to naturally extend the continental shelf, which has caused more drastic disputes of maritime delimitation. This paper devotes to clarify...The United Nations Convention on the Law of the Sea entitled the coastal States to naturally extend the continental shelf, which has caused more drastic disputes of maritime delimitation. This paper devotes to clarifying the significant concept of natural prolongation through an effect method combing the legal principles and technical analysis. Firstly, the classic samples with respect of the development of geological features are traced. Based on these samples, the classification with a model is proposed in order to affirm the concept＇s significance under certain geomorphologic situations. Lastly, scientific analysis is used to present two potential prolongation situations and emphasize that all the technical analysis on maritime delimitation should be complied with international law and protect the common interest of all the mankind.展开更多
Previous literature shows that scholars differ considerably on what verbal reduplication indicates.By making use of an oral speech corpus,we analyzed and tested the data and found that the functions of verbal reduplic...Previous literature shows that scholars differ considerably on what verbal reduplication indicates.By making use of an oral speech corpus,we analyzed and tested the data and found that the functions of verbal reduplication have close relationships with the time that the action takes place.this is a point that is different from other perfective aspectual categories,which are usual ly used in the past time.Due to its basic meaning,the delimitative aspect shows preference for volitional verbs.It has the semantic features of dynamicity,perfectivity,delimitativity,and transitoriness,yet it stresses the non-durativity of the event.展开更多
Gracilariopsis lemaneiformis is a widely reported species of marine red algae, with records from around the world. Particularly in Mexico, it has been recorded along the coasts of the Gulf of Mexico and the Mexican Ca...Gracilariopsis lemaneiformis is a widely reported species of marine red algae, with records from around the world. Particularly in Mexico, it has been recorded along the coasts of the Gulf of Mexico and the Mexican Caribbean as well as the Tropical Mexican Pacific;so, its current distribution on the Mexican coasts is disjunct. From its molecular characterization with COI-5P and rbcL sequences of specimens collected at sites in Mexico where this species has been most frequently recorded, our aim was to re-evaluate the current distribution of Gp. lemaneiformis on the Mexican coasts and discuss the taxonomic implications. Phylogenetic analysis, supported by DNA species delimitation methods, genetic distances and morphological comparisons, showed that the current disjunct distribution of Gp. lemaniformis in Mexico is a consequence of taxonomic misidentifications. From our results, Gp. lemaneiformis is the only species of the genus with a distribution in the Tropical Mexican Pacific, whereas Gp. tenuifrons is the only species with a distribution in the Gulf of Mexico and the Mexican Caribbean. Also, we propose that Gp. cata-luziana is to be merged with Gp. tenuifrons, while Gp. costarisensis is to be merged with Gp. lemaneiformis.展开更多
Chrysopidae are a family of Neuroptera of significant importance in biocontrol against agricultural pests because of their predatory larvae.Currently,the taxonomy of Chrysopidae lacks a comprehensive revision,which im...Chrysopidae are a family of Neuroptera of significant importance in biocontrol against agricultural pests because of their predatory larvae.Currently,the taxonomy of Chrysopidae lacks a comprehensive revision,which impedes the exploration of species diversity as well as the selection and the conservation of green lacewings as biocontrol agents.We have established a DNA barcode reference library of the Chinese green lacewings based on an approximately complete sampling(95.63%)in 25 of the 34 provincial regions in China,comprising 1119 barcodes of 25 genera and 197 species(representing 85%genera and 43.62%species from China).Combining other 1049 high quality green lacewing DNA barcodes,we first inferred the optimal threshold of interspecific genetic divergence(1.87%)for successful species identification in multiple simulated scenarios based on present data.We further inferred the threshold of genetic divergence(7.77%)among genera with biocontrol significance.The inference and performance of the threshold appears to be mainly associated with the completeness of sampling,the proportion of closely related species,and the analytical approaches.Six new combinations,Apertochrysa platypa(Yang&Yang,1991)comb.nov.,Apertochrysa shennongana(Yang&Wang,1990)comb.nov.,Apertochrysa pictifacialis(Yang,1988)comb.nov.,Apertochrysa helana(Yang,1993)comb.nov.,Plesiochrysa rosulata(Yang&Yang,2002)comb.nov.,and Signochrysa hainana(Yang&Yang,1991),are proposed according to integrative species delimitation.Our library and optimal threshold will effectively facilitate the exploration of species diversity of green lacewings.Our study also provides a methodological reference in molecular delimitation of other insects.展开更多
Species are not only the fundamental units of taxonomy but also the basic units of pest management.Insects of Conogethes are important agricultural and forestry pests.However,species boundaries within Conogethes often...Species are not only the fundamental units of taxonomy but also the basic units of pest management.Insects of Conogethes are important agricultural and forestry pests.However,species boundaries within Conogethes often appear obscure.In the present study,we reevaluated the species status of Conogethes by applying three species delimitation approaches based on the mitochondrial DNA sequences,with particular emphasis on the yellow peach moth C.punctiferalis(Guenée,1854).We first optimized species delimitation and inter-species genetic divergence threshold using a DNA barcoding dataset.The results revealed that several nominal species of Conogethes species harbored deeply diverged mitochondrial lineages which were recognized as independent species by the species delimitation methods.The p-distance between the delimited putative species ranged from 0.0159 to 0.1321 with a mean of 0.0841.Then we refined the species status of C.punctiferalis using the smallest interspecific distance threshold based on a geographically comprehensive population-scale dataset.This procedure narrowed the species concept of C.punctiferalis to a genetically coherent unit.Further investigation of its intraspecific divergence in the geographic context revealed that the refined C.punctiferalis was still widely distributed with the same or highly similar mitochondrial haplotypes occurring across South and East Asia.展开更多
基金Under the auspices of Shanghai Foundation Item for Philosophy and Social Sciences (No 2005BCK004)Research Center on Metropolitan Regions of China (No RCMRC 07006)
文摘In metropolitan regions, the change in the strength of "flows" between a core city and surrounding cities re-flects the range of the core city's influence, while the gravity between core city and other cities reflects the strength of potential relation between them. This article firstly attempts to delimit the boundary of metropolitan regions with the two dimensions measure combining "flows" and gravitation. The former is measured through the flow of people be-tween the core city and surrounding cities, and the latter is measured through both population and gross domestic products (GDP) of the core city and surrounding cities. The hierarchy of the cities within a metropolitan region is classified in order to emphasize the roles of the cities belonging to the metropolitan regions, different from the general way through population scale and administrative level, and is typical in China. This paper uses the Shanghai metropolitan region as a research case, determining boundary of this metropolitan region clearly and classifying hierarchy of the cities within the region. The final results are significantly different to previous work, even overthrowing the traditional system of urban hierarchy partly. It is helpful to highlight the function of cities in organizing the regional economy, the level structure of metropolitan regions, and each city's relative importance in a metropolitan region, which can be taken as scientific basis for planning integrated regions or urban systems.
基金Supported by the Zhejiang Provincial Key Research and Development Program (No.2021C02047)。
文摘Accurate species identification is a key component of biodiversity research.DNA barcoding is an effective molecular method used for fish species identification.We aimed to study the DNA barcoding of fish in Zhoushan coastal waters,explore the differences and applicability of two gene fragments(12S rRNA and COI)of DNA barcoding in fish species identification,and established a comprehensive fish barcoding reference database.Two hundred and eighty-seven captured fish samples from Zhoushan coastal waters were identified using morphological characteristics and DNA barcoding.A total of 26412S rRNA sequences(belonging to eight orders,31 families,55 genera,and 66 species)and 188 COI sequences(belonging to seven orders,30 families,48 genera,and 58 species)were obtained.The lengths of the 12S rRNA sequences ranged from 165 to 178 bp,and the guanine-cytosine(GC)content was 45.37%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.10%and 26.66%,respectively.The length of the COI sequence ranged 574–655 bp,and the content of GC was 45.97%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.16%and 27.45%,respectively.The minimum interspecific genetic distances of 12S rRNA and COI(1.23%and 1.86%)were both greater than their maximum intraspecific genetic distances(2.42%and 8.66%).Three molecular analyses(NJ tree,ABGD,and GMYC)were performed to accurately identify and delineate species.Clustering errors occurred when the 12S rRNA sequences were delimited using the NJ tree method,and the delimitation results of ABGD and GMYC are consistent with the final species identification results.Our results demonstrate that DNA barcoding based on 12S rRNA and COI can be used as an effective tool for fish species identification,and 12S rRNA has good application prospects in the environmental DNA(eDNA)metabarcoding of marine fish.
基金supported by a Singapore National Research Foundation (NRF) Investigatorship (WBS A-8001397-00-00) to FER.
文摘Much confusion has surrounded the taxonomy of the Collared Scops Owl(Otus bakkamoena)complex,distributed widely across tropical and subtropical Asia.Often divided into three species,modern taxonomies disagree on its treatment,as a lack of deep mitochondrial DNA divergence is seemingly in contrast with patterns of vocal differentiation.Analysing a dataset of territorial calls of 122 individuals across Asia,we identified a vocal leapfrog pattern in which owl populations at the eastern and western ends of the distribution sound more similar to each other but are separated by different-sounding populations in between.The boundaries between vocal types are not congruent with traditional species boundaries.Our data allow for a re-drawing of species boundaries and reveal that Collared Scops Owls follow a biogeographic pattern rare in Southeast Asian birds.However,this pattern is shared with several other owl complexes in that peninsular Malaysian populations form part of a continental Asian species centred further north in Southeast Asia rather than forming part of a Sundaic species centred in the adjacent Indonesian Archipelago.
基金Chinese Joint Seismological Science Foundation (100110).
文摘The seismic hazard of research area is evaluated by probabilistic analysis method for three different seismic statis-tical zone scenarios. The influence of uncertainty in seismic statistical zone delimiting on the evaluation result is discussed too. It can be seen that for those local sites along zone's border or within areas with vast change of upper bound magnitude among different scenarios the influence on seismic hazard result should not be neglected.
文摘Geological anomaly is a geological body or geological body combination different from its surroundings in composition, structure, or genetic sequence. If there is a value (value interval ) that works as a valve representing the background field, exceeding or lower than the valve value,it is called a geological anomaly. Geological anomalies can be divided into high geological anomaly and low geological anomaly .The former shows the area that is more complex in composition, Structure or genetic sequence than its surroundings; while the latter just gives an opposite indication, i. e. much simpler. According to their distribution and delimitation markers, geological anomalies can be classified into (1)global geological anomaly; (2)regional geological anomaly; (3) local geological anomaly; (4) minor geological anomaly and (5)micro-geological anomaly .The methods for delimiting geological anomalies include (1)crustal elevation-subsidence coefficieat (G value ) determination; (2) geological complex coefficient (C value ) determination; (3) entropy (H value ) determination; (4) geological similarity coefficient (S value ) determination and (5 ) geological correlation coefficient (R value ) determination. As the result of the movements of Eurasian, Pacific and Indian Plates, the Chinese geological anomalies, including 11 regional ones and 32 main local ones, most Paleozoic in age, are distributed in strip on the margin or the outer and inner folded zones in the east and west arcs of the block symmetric arc tectonic system (BSATS), which controls the distribution of various minerals in China. Thus, geological anomaly theory is of great significance in searching for large, super-large and very large ore deposits.
文摘Objective:To examine and study the morphology,epidemiology,and molecular phylogeny of Anisakis larvae in blue mackerel[Scomber australasicus(Cuvier,1832)]and Indian mackerel[Rastrelliger kanagurta(Cuvier,1816)]using light microscope,scanning electron microscope,molecular phylogeny,and species delimitation methods for confirmation and investigation of Anisakis species and their evolutionary relationship.Methods:A total of 90 fish(45 per species)were purchased from a department store in Chiang Mai,Thailand.Anisakis samples were investigated for morphological characteristics using light and scanning electron microscopes.Molecular phylogeny and species delimitation methods based on the cox2 gene were performed.Results:The prevalence,mean intensity(Mean±SEM),and mean abundance of Anisakis larvae(Mean±SEM)in blue mackerel were 77.78%,6.74±1.320,and 5.24±1.107,respectively,and in Indian mackerel,these values were 13.33%,2.50±0.764,and 0.33±0.159,respectively.Scanning electron microscopy showed the detail of morphological characteristics and provided the different shapes of mucron and excretory pores in Anisakis larvae congruent with the phylogenetic tree.The species tree was congruent with the phylogenetic tree.Conclusions:The prevalence,mean intensity,and mean abundance of Anisakis larvae were higher in blue mackerel.To the best of our knowledge,this is the first time that Anisakis pegreffii was found in blue mackerel in Thailand.The phylogenetic tree also supported the morphological data of Anisakis larvae.However,species delimitation based on cox2 revealed 1-3 possible cryptic species in this genus.Anisakis spp.contamination of fish products is unpleasant and a health concern considering human infection with larvae(anisakiasis)arises.
基金supported by the programs of the Strategic Priority Research Program B of the Chinese Academy of Sciences (CAS) (No. XDB31000000)the National Natural Science Foundation of China (Grant No. 31460091)+2 种基金the Na tional Animal Collection Resource Center, China (Grant No. 2005DKA21402)the Application of Amphibian Natural Antioxidant Peptides as Cosmetic Raw Material Antioxidants (QKZYD [2020]4002)the National Top Discipline Construction Project of Guizhou Province,Geography in Guizhou Normal University (No. 85 2017 Qianjiao Keyan Fa)。
文摘The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal.
基金Supported by the National Natural Science Foundation of China(Nos.31372532,41006084,41276166)the Project for Outstanding Young Teachers in Higher Education of Guangdong,China(No.Yq2013093)
文摘Sparids are of considerable economic importance in marine fishery and aquaculture in China, and the species diversity of this group is considered relatively high. However, the accurate species identification and delimitation of sparids in China remain unaddressed. In this study, we used mitochondrial cytochrome oxidase subunit ?(COI) and 16S ribosomal RNA(16S) genes to conduct DNA barcoding and species delimitation in eleven sparid species from the coastal waters of China. Based on Kimura-2 parameter genetic distances, the mean intraspecific/interspecific variation for COI and 16S were calculated as 0.004/0.152 and 0.002/0.072, respectively. All the conspecific individuals formed monophyletic clusters in neighbour-joining trees of both markers. An obvious barcoding gap was detected for each species, and a common genetic threshold of 1.3% sequence divergence was defined for species delimitation in both markers. Although the sequence variation of 16S was generally lower than that of COI, the results indicated that sparid species could be ef fectively and accurately identified and delimited by COI as well as 16S. Thus, we propose that the COI gene serve as the standard DNA barcode for sparids, and that the 16S gene could also be an ideal candidate barcode. Moreover, each of the six sparid species( Argyrops spinifer, Rhabdosargus sarba, Dentex hypselosomus, Acanthopagrus latus, Acanthopagrus australis and Acanthopagrus berda) showed high intraspecific divergence(>1.3% genetic threshold) with the remarkable geographic lineages in the Indo-West Pacific oceans, which supported that potential unrecognized cryptic species were in them. The potential cryptic diversity revealed here might be primarily attributed to the allopatric divergences caused by the long-term geographic isolation between the Indian and West Pacific oceans or between the opposite sides of the Indian Ocean. The results further suggest that a revision of taxonomic status of these species is required, followed by development of a biodiversity conservation strategy.
基金A grant from the National Institute of Biological Resources(NIBR)funded by the Ministry of Environment(MOE) of the Republic of Korea under contract No.2013-02-013
文摘Codium, one of the largest marine green algal genera, is difficult to delimit species boundary accurately based on morphological identification only. DNA barcoding is a powerful tool for discriminating species of seaweeds. The plastid elongation factor TU （tufA） is considered as maker to perform DNA barcoding of green algal species than rbcL gene due to universality and rapid evolution rate. We conducted DNA barcoding application to Codium specimens from the Jeju Island, Korea to overcome the limit of morphological identification and to confirm the species diversity. As a result of applying tufA marker, we newly generated fifty-five tufA barcodes to resolve eight species. TufA marker exhibited 6.1%–21.8% interspecific divergences, wider than the gap of rbcL exon 1, 3.5%–11.5%. Molecular analysis of rbcL exon 1 sequences of Codium revealed eight distinct species like tufA analysis separated in five phylogenetic groups. DNA barcoding of the genus Codium using tufA marker is more helpful to overcome the limit of morphological identification, and this is more potential to reveal cryptic species and to resolve the relationships among subspecies than rbcL analysis alone. The complement of tufA barcoding and rbcL analyses including morphology for the genus Codium in the northwestern Pacific will give much more reliable achievement for discovering species diversity and resolving the phylogenetic relationships.
基金the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK0502)National Key R&D Program of China(2017YFC0505200)+1 种基金National Natural Science Foundation of China(31460096 and 31590823)State Key Laboratory of Phytochemistry and Plant Resources in West China(P2020-KF04).
文摘Delimiting species requires multiple sources of evidence.Here,we delimited two varieties of Halenia elliptica(Gentianaceae)using several lines of evidence,including morphological traits and mating system in a sympatric population,phylogenetic relationships based on nrITS and cpDNA(rpl16)data,and complete chloroplast genome sequences.Comparative analysis of 21 morphological traits clearly separates the two varieties of H.elliptica.Examination of the flowering process and pollination treatments indicate that H.elliptica var.grandiflora produces seeds via outcrossing,whereas H.elliptica var.elliptica produces seeds via mixed mating.Furthermore,hand-pollinated hybridization of the two varieties produced no seeds.Observations of pollinators showed that when bees began a pollination bout on H.elliptica var.grandiflora they preferred to continue pollinating this variety;however,when they began a pollination bout on H.elliptica var.elliptica,they showed no preference for either variety.Phylogenetic analysis confirmed the monophyly of H.elliptica,which was further divided into two monophyletic clades corresponding to the two varieties.A large number of variants from the chloroplast genomes reflected remarkable genetic dissimilarities between the two varieties of H.elliptica.We recommend that the two varieties of H.elliptica should be revised as two species(H.elliptica and H.grandiflora).Our findings indicate that H.elliptica varieties may have split into two separate species due to a shift in mating system,changes in flowering phenology and/or post-pollination reproductive isolation.
文摘This paper makes a summary of status of delimitation of seismic zones and belts of China firstly in aspects of studying history, purpose, usage, delimiting principles, various presenting forms and main specialties. Then the viewpoints are emphasized, making geographical divisions by seismicity is just the most important purpose of delimiting seismic belts and the concept of seismic belt is also quite different from that of seismic statistical zone used in CPSHA method. The concept of seismic statistical zone and its history of evolvement are introduced too. Large differences between these rwo concepts exist separately in their statistical property, actual meaning, gradation, required scale, and property of refusing to overlap each other, aim and usage of delimitation. But in current engineering practice, these two concepts are confused. On the one hand, it causes no fit theory for delimiting seismic statistical zone in PSHA to be set up; on the other hand, researches about delimitation of seismic belts with purposes of seismicity zoning and studying on structural environment, mechanism of earthquake generating also pause to go ahead. Major conclusions are given in the end of this paper, that seismic statistical zone bases on the result of seismic belt delimiting, it only arises in and can be used in the especial PSHA method of China with considering spatially and temporally inhomogeneous seismic activities, and its concept should be clearly differentiated from the concept of seismic belt.
文摘The central value 23°26′17″ of the Tropic of Cancer is used for delimiting the standard position of the Tropic of Cancer as well as countries, regions and cities which the Tropic of Cancer traverses. It is confirmed that the Tropic of Cancer runs through 19 countries and regions in the world, and it traverses Yunnan, Guangxi, Guangdong, Fujian （sea area） and Taiwan provinces in China. At the same time, regions which the Tropic of Cancer traverses are divided into three regions, namely the extensive Tropic of Cancer region, the Tropic of Cancer region and the core area of the Tropic of Cancer. The series of delimitation and division aims to explore ways of sustainable development under the restriction of resources and environment and build collaborative development areas of the Tropic of Cancer at all leaves, especially setting up the collaborative de- velopment zone of the Tropic of Cancer in China and international collaborative development circle of the Tropic of Cancer.
文摘To solve some unreasonable problems in the acceptance process of the delimitation project of grain production functional zones,the acceptance results of grain production functional zones in Fangzi District,Weifang City were elaborated from the aspects of the third party organization,inspectors,expert group,acceptance criteria,acceptance method,acceptance contents,etc.,and the overall performance of the project was reviewed.The problems that need to be rectified during the implementation of the project were put forward,and the irrationality of the acceptance and the places that need to be improved were pointed out,which would provide a better guiding value for the delimitation of grain production functional zone and the acceptance and performance evaluation of similar projects.
文摘On the Pacific coast of Russia implementation of the methodology of the integrated nature management has a number of peculiarities. On the one hand, these districts are characterized by severe hydrometeorological conditions. On the other hand, Russia has no applicable legislation on coastal issues. Thus, to prepare informational, theoretical and methodical bases for organization of sustained nature management in coastal zones of the Russian Federation, we developed hierarchy structure of delimitation of coastal areas and recommendations for their development on the basis of nature resource and social-economic zoning. Zoning of the Russian Far East is suggested to include two major directions： （1） planning of sustainable development of the region and （2） solving contradictions between fisheries and productions of oil and gas in the coastal zones.
文摘Issues concerning on the continental shelf and in the exclusive economic zone between Turkey and the Greek Cypriot Administration (GCA) have been more controversial. This study answers the following questions:(a) What is the main arguments of the Parties?(b) How the exclusive economic zone could be declared?(c) Does median line applicable to the delimitation law without taken the related circumstances in the Eastern Mediterranean?(d) Can any maps on claimed exclusive economic zone borders publish without maritime boundary delimitation agreements, officially? The main intent of the study is to evaluate the different perspectives of the Parties on maritime delimitation and to evaluate the boundaries of the exclusive economic zone bounded by the European Union on the European Asia and Europe Africa Interconnected Cable Network Projects maps in the Eastern Mediterranean.
基金The National Social Science Foundation of China under contract No.16CFX069China Postdoctoral Science Foundations under contract Nos 2015M581913 and 2016T90531the Fundamental Research Funds for the Central Universities
文摘The United Nations Convention on the Law of the Sea entitled the coastal States to naturally extend the continental shelf, which has caused more drastic disputes of maritime delimitation. This paper devotes to clarifying the significant concept of natural prolongation through an effect method combing the legal principles and technical analysis. Firstly, the classic samples with respect of the development of geological features are traced. Based on these samples, the classification with a model is proposed in order to affirm the concept＇s significance under certain geomorphologic situations. Lastly, scientific analysis is used to present two potential prolongation situations and emphasize that all the technical analysis on maritime delimitation should be complied with international law and protect the common interest of all the mankind.
文摘Previous literature shows that scholars differ considerably on what verbal reduplication indicates.By making use of an oral speech corpus,we analyzed and tested the data and found that the functions of verbal reduplication have close relationships with the time that the action takes place.this is a point that is different from other perfective aspectual categories,which are usual ly used in the past time.Due to its basic meaning,the delimitative aspect shows preference for volitional verbs.It has the semantic features of dynamicity,perfectivity,delimitativity,and transitoriness,yet it stresses the non-durativity of the event.
基金supported by the projects:UAMI-CBS2019-2022:session 15.18-281118UAMI-CA-117,PRODEPcontains some results from the PhD project of Oscar E.Hernandez in the Doctorado en Ciencias Biologicas y de la Salud graduate program of the Universidad Autonoma Metropolitana.
文摘Gracilariopsis lemaneiformis is a widely reported species of marine red algae, with records from around the world. Particularly in Mexico, it has been recorded along the coasts of the Gulf of Mexico and the Mexican Caribbean as well as the Tropical Mexican Pacific;so, its current distribution on the Mexican coasts is disjunct. From its molecular characterization with COI-5P and rbcL sequences of specimens collected at sites in Mexico where this species has been most frequently recorded, our aim was to re-evaluate the current distribution of Gp. lemaneiformis on the Mexican coasts and discuss the taxonomic implications. Phylogenetic analysis, supported by DNA species delimitation methods, genetic distances and morphological comparisons, showed that the current disjunct distribution of Gp. lemaniformis in Mexico is a consequence of taxonomic misidentifications. From our results, Gp. lemaneiformis is the only species of the genus with a distribution in the Tropical Mexican Pacific, whereas Gp. tenuifrons is the only species with a distribution in the Gulf of Mexico and the Mexican Caribbean. Also, we propose that Gp. cata-luziana is to be merged with Gp. tenuifrons, while Gp. costarisensis is to be merged with Gp. lemaneiformis.
基金supported by the Beijing Natural Science Foundation(No.5212011)the National Natural Science Foundation of China(Nos.32170448,32130012)+1 种基金the 2115 Talent Development Program of China Agricultural Universitythe National Animal Collection Resource Center,China.
文摘Chrysopidae are a family of Neuroptera of significant importance in biocontrol against agricultural pests because of their predatory larvae.Currently,the taxonomy of Chrysopidae lacks a comprehensive revision,which impedes the exploration of species diversity as well as the selection and the conservation of green lacewings as biocontrol agents.We have established a DNA barcode reference library of the Chinese green lacewings based on an approximately complete sampling(95.63%)in 25 of the 34 provincial regions in China,comprising 1119 barcodes of 25 genera and 197 species(representing 85%genera and 43.62%species from China).Combining other 1049 high quality green lacewing DNA barcodes,we first inferred the optimal threshold of interspecific genetic divergence(1.87%)for successful species identification in multiple simulated scenarios based on present data.We further inferred the threshold of genetic divergence(7.77%)among genera with biocontrol significance.The inference and performance of the threshold appears to be mainly associated with the completeness of sampling,the proportion of closely related species,and the analytical approaches.Six new combinations,Apertochrysa platypa(Yang&Yang,1991)comb.nov.,Apertochrysa shennongana(Yang&Wang,1990)comb.nov.,Apertochrysa pictifacialis(Yang,1988)comb.nov.,Apertochrysa helana(Yang,1993)comb.nov.,Plesiochrysa rosulata(Yang&Yang,2002)comb.nov.,and Signochrysa hainana(Yang&Yang,1991),are proposed according to integrative species delimitation.Our library and optimal threshold will effectively facilitate the exploration of species diversity of green lacewings.Our study also provides a methodological reference in molecular delimitation of other insects.
基金This study was supported by a starting fund from Hebei Agricultural University and the State Key Laboratory of North China Crop Improvement and Regulation(YJ2020028).
文摘Species are not only the fundamental units of taxonomy but also the basic units of pest management.Insects of Conogethes are important agricultural and forestry pests.However,species boundaries within Conogethes often appear obscure.In the present study,we reevaluated the species status of Conogethes by applying three species delimitation approaches based on the mitochondrial DNA sequences,with particular emphasis on the yellow peach moth C.punctiferalis(Guenée,1854).We first optimized species delimitation and inter-species genetic divergence threshold using a DNA barcoding dataset.The results revealed that several nominal species of Conogethes species harbored deeply diverged mitochondrial lineages which were recognized as independent species by the species delimitation methods.The p-distance between the delimited putative species ranged from 0.0159 to 0.1321 with a mean of 0.0841.Then we refined the species status of C.punctiferalis using the smallest interspecific distance threshold based on a geographically comprehensive population-scale dataset.This procedure narrowed the species concept of C.punctiferalis to a genetically coherent unit.Further investigation of its intraspecific divergence in the geographic context revealed that the refined C.punctiferalis was still widely distributed with the same or highly similar mitochondrial haplotypes occurring across South and East Asia.
