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Correlation of personality with individual reproductive success in shrub-nesting birds depends on their life history style
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作者 Jianchuan Li Wen Zhang +5 位作者 Ningning Sun Yujie Wang Lifang Gao Ran Feng Liqing Fan Bo Du 《Avian Research》 SCIE CSCD 2024年第1期42-49,共8页
Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain ... Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain unresolved.We addressed these two questions in three shrub-nesting birds,the Azure-winged Magpie(Cyanopica cyanus,AM),White-collared Blackbird(Turdus albocinctus,WB),and Brown-cheeked Laughingthrush(Trochalopteron henrici,BL).The personality type of an individual was first identified according to its response to a territorial intruder.Then,we compared the fleeing distance,breeding parameters,and differential expressed genes(DEGs) in the brain transcriptome between bold and shy breeders.In the three species,bold breeders exhibited more aggressiveness towards an intruder of their territory than did shy breeders.The reproductive success of bold breeders was significantly higher than that of shy breeders in AM but not in WB and BL.The three species shared one DEG,crabp1,which was up-regulated in bold relative to in shy individuals.By regulating the expression of corticotropin-releasing hormone,higher crabp1 gene expression can decrease cellular response to retinoic acid.Therefore,bold individuals are insensitive to external stresses and able to exhibit more aggressiveness to intruders than their shier counterparts.Aggressiveness is beneficial to bold individuals in AM but not in WB and BL because the former could evoke neighbors to make the same response of defending against intruders but the latter could not.Although a personality trait may have the same genetic basis across species,its correlation with reproductive success depends largely on the life history style of a species. 展开更多
关键词 BOLDNESS life history style PERSONALITY Reproductive success Transcriptome analysis
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A preliminary study on life history of marine red alga Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li
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作者 Bingxin HUANG Yao ZHANG +4 位作者 Yue CHU Youxuan GUO Junxia LIANG Jianan QIN Lanping DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期915-922,共8页
Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li is a common species in the genus Stylonema,but there are limited reports on morphological taxonomy and a lack of studies on life history and the regulation of ea... Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li is a common species in the genus Stylonema,but there are limited reports on morphological taxonomy and a lack of studies on life history and the regulation of early development.The early development,discoid formation,and erect thallus growth of Stylonema alsidii f.ramosum were observed under laboratory conditions.In addition,the influence of main environmental factors such as temperature and light intensity on its development was briefly studied,and various stages of its life history were observed.The result shows:(1)there are two reproductive modes:asexual reproduction and sexual reproduction;(2)the morphology of this species varies in different degrees under laboratory culture conditions;(3)sexual reproduction and asexual reproduction can coexist under suitable conditions.Five pathways of life history were inferred from experimental phenomena.Mature sporophytes form mature gametophytes by producing initially isolated or initially attached monospore,and mature gametophytes form mature sporophytes by fertilization of eggs and sperms.The sexual and asexual reproduction processes of Stylonema alsidii f.ramosum were reported for the first time,and this is also the first report on sexual reproduction in the genus Stylonema. 展开更多
关键词 Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li life history environmental factor asexual reproduction sexual reproduction
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Study on fish life history traits and variation in the Taiwan Strait and its adjacent waters 被引量:3
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作者 HU Wenjia YE Guanqiong +4 位作者 LU Zhenbin DU Jianguo CHEN Mingru CHOU Loke Ming YANG Shengyun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第2期45-54,共10页
Large portions of the world's fishery resources are overexploited. Life history traits of fish species are important indicators to reveal different life history strategies and to indicate population responses to fish... Large portions of the world's fishery resources are overexploited. Life history traits of fish species are important indicators to reveal different life history strategies and to indicate population responses to fishing pressures. For this study, empirical data on fishing grounds located in the coastal area between Fujian Coast and Taiwan Island were collected. These areas have experienced severe overfishing in the past 30 years, leading to changes in the structure and function of the fish communities. Fifty-one commercial fish species in this fishing ground were selected to study the life history traits. Using the life history traits, all the species were grouped into five different life history strategies by principle component analysis. More than 60% of the species were categorized in Group 5 that was similar to r-strategists. Twenty-five commercial species were selected for further analysis of changes in life history variables, and to discuss the population responses to exploitation. Results showed that most of the species appeared to become smaller size, shorter life, earlier maturation and faster growing under long-term exploitation. The exploitation rate of each species was also calculated to further discuss the impacts of fishing pressures to fish populations. Four species were found with the severest changes on life history traits indicating some of the species might be more susceptible to exploitation. This study on fish life history traits and their long-term variations under fishing pressures could provide important scientific implications for fishery management and conservation. 展开更多
关键词 life history traits fish life history strategy fishery exploitation the Taiwan Strait
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Isoenergetic-practical and semi-purified diets for protein requirement determination in Hermetia illucens larvae:consequences on life history traits
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作者 Sara Bellezza Oddon Ilaria Biasato Laura Gasco 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第3期897-906,共10页
Background:Black soldier fly(BSF)is one of the most promising species for the intensive breeding of insects given its adaptability and its efficiency in the conversion of waste.To maximize the production and use waste... Background:Black soldier fly(BSF)is one of the most promising species for the intensive breeding of insects given its adaptability and its efficiency in the conversion of waste.To maximize the production and use waste as substrates,it is essential to determine the larvae nutritional requirements.The study aims to evaluate the effects of5 practical,semi-purified and isoenergetic diets(PSPID)with increasing protein levels(10%,CP10;14%,CP14;16%,CP16;19%,CP19)on BSF life history traits.A total of 2000 six-day-old larvae were weighed and divided into groups of 100(4 replicates/treatment[PSPID and Gainesville diet(GA)used as environmental control]).In larva-prepupa stage,sampling was carried out on 30 individuals/replicate,while in prepupa-adult stage on 35.Results:In the whole larval stage,the CP16 treatment performed better when compared to the other groups.At18 days old,the CP14 treatment showed a higher weight than the CP19(P<0.01),while the CP10 and CP16weights were intermediate.On the contrary,the CP10 prepupae weight was higher than the CP19(P<0.01).The CP10 and CP14 pupae performed better in terms of weight when compared to the others(P<0.01).The dietary treatments did not affect the adult parameters.The sex significantly influenced both the exuvia weight,which was the greatest in females(P<0.001),and the fly lifespan,longest in males(P<0.05).Fly lifespan was also influenced by the interaction between treatment and sex,with the CP19 females showing a longer life than the others(P<0.05).Conclusions:In conclusion,the optimal protein level considering the whole larval stage is 16%on dry matter(DM).At 18 days old,looking at the size intended for the meal production,it can be considered 14%on DM.The result obtained on adult emergence in PSPID may not be attributable to the protein content.Further researches on macronutrients requirements determination have to be conducted to evaluate the substrates composition effects on BSF life history traits. 展开更多
关键词 Hermetia illucens life history traits Nutritional requirements Semi-purified
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Opportunistic-tended life history traits of Siniperca kneri in the Three Gorges Reservoir,China: potential responses to impoundment
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作者 ZHAO Shasha CHENG Fei +2 位作者 HOU Gang HU Zhengyu XIE Songguang 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期694-705,共12页
Reservoir impoundment changes original fluvial habitats into lentic environments. Fish species adapted to lentic habitats may take the advantage of such habitat changes and show typical life history traits might facil... Reservoir impoundment changes original fluvial habitats into lentic environments. Fish species adapted to lentic habitats may take the advantage of such habitat changes and show typical life history traits might facilitate the population increase. Siniperca kneri rarely occurred in fishery landing in the Three Gorges Reservoir (TGR) area before its impoundment in 2003, but it is now a dominant species. In this study, a total of 438 females of S . kneri were collected monthly during September 2012 through January 2014 using gill nets in the TGR. The age, growth, and reproductive biology were then investigated, and compared with other S . kneri populations. The standard length at age 1 was 149.9 mm in the TGR, which is larger than the three compared populations (i.e., Sandaohe Reservoir, Xinfengjiang Reservoir, and North River), but smaller than one (the Guishi Reservoir). The youngest mature female in the TGR was age 1, which is younger than that of the two compared populations (i.e., Xinfengjiang Reservoir and the North River). The relative fecundity in the TGR was 140 eggs/g, which is higher than that of the only available compared population (Xinfengjiang Reservoir, 96 eggs/g). Our results demonstrated that S . kneri in the TGR tended to have faster growth in the first year, a younger age at first maturation, and higher reproductive eff ort. We suggest that such opportunistic-tended life history traits might facilitate rapid increase of the population. 展开更多
关键词 SINIPERCA kneri life history traits OPPORTUNISTIC growth REPRODUCTION COLONIZATION
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Host plant traits play a crucial role in shaping the composition of epiphytic microbiota in the arid desert,Northwest China
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作者 ZHANG Jun ZHANG Yuanming ZHANG Qi 《Journal of Arid Land》 SCIE CSCD 2024年第5期699-724,共26页
Phyllosphere microorganisms are a crucial component of environmental microorganisms,highly influenced by host characteristics,and play a significant role in plant health and productivity.Nonetheless,the impact of host... Phyllosphere microorganisms are a crucial component of environmental microorganisms,highly influenced by host characteristics,and play a significant role in plant health and productivity.Nonetheless,the impact of host characteristics on shaping phyllosphere microbial communities of plants with different life forms remains ambiguous.Utilizing high-throughput sequencing technology,this study analyzed the diversity and community composition of phyllosphere epiphytic microorganisms(e.g.,bacteria and fungi)of various plant life forms in the hinterland of the Gurbantunggut Desert,Northwest China.Functional annotation of prokaryotic taxa(FAPROTAX)and fungi function guild(FUNGuild)were employed to assess the ecological functions of microorganisms and to investigate the role of stochastic and deterministic processes in shaping phyllosphere microbial communities.Result showed a diverse array of phyllosphere epiphytic microorganisms in the desert plants,with Proteobacteria,Cyanobacteria,and Actinobacteriota dominating bacterial community,while Ascomycota and Basidiomycota were prevalent in fungal community.Comparison across different plant life forms highlighted distinct microbial communities,indicating strong filtering effects by plant characteristics.FAPROTAX prediction identified intracellular parasites(accounting for 27.44%of bacterial community abundance),chemoheterotrophy(10.12%),and phototrophy(17.41%)as the main functions of epiphytic bacteria on leaves of different life form plants.FUNGuild prediction indicated that phyllosphere epiphytic fungi primarily served as Saprotrophs(81.77%),Pathotrophs(17.41%),and Symbiotrophs(0.82%).Co-occurrence network analysis demonstrated a predominance of positive correlations among different microbial taxa.Raup-Crick dissimilarity index analysis revealed that deterministic processes predominantly influenced phyllosphere bacterial and fungal community assembly.Variance partitioning analysis and random forest modeling suggested that plant leaf functional traits significantly impacted both bacterial and fungal community composition,with fungal community composition showing a closer association with leaf nutrients and physiology compared with bacterial community composition.The distinct responses of bacterial and fungal communities to plant traits were attributed to the differing properties of bacteria and fungi,such as bacteria having higher potential dispersal rates and broader ecological niches than fungi.Overall,the results indicate that phyllosphere bacterial and fungal communities undergo similar community assembly processes,with fungi being more influenced by plant characteristics than bacteria.These findings offer novel insights into the ecology of phyllosphere microbial communities of desert plants. 展开更多
关键词 phyllosphere epiphytic bacteria phyllosphere epiphytic fungi community structure community diversity functional diversity plant life form plant functional traits
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Life History Traits and Mechanisms of Endangerment in Ranalisma rostratum
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作者 Wang Jianbo,Chen Jiakuan, Li Rongqian(College of Life Sciences,Wuhan University,Wuhan 430072, China) 《Wuhan University Journal of Natural Sciences》 EI CAS 1998年第2期231-234,共4页
Ranalisma rostratum (Alismataceae) is an endangered aquatic plant, and now there is only one population existing in China. In its natural habitat, Huli marsh in Chaling, Hunan province, the best growing plants have be... Ranalisma rostratum (Alismataceae) is an endangered aquatic plant, and now there is only one population existing in China. In its natural habitat, Huli marsh in Chaling, Hunan province, the best growing plants have been observed at microsites where the water depth is 5~10cm, and the plants grow in emergent form.R. rostratum reproduces asexually or sexually. The recruitment of asexual propagules into population is a very important way to maintain the natural population size. Although seed production does not appear to limitR. rostratum, restricted dispersal of propagules and seeds, low seed viability, low germinability, slow growth of seedlings under all conditions, and habitat loss due to agriculture appear to be more important reasons for the endangerment of this plant. 展开更多
关键词 Key words Ranalism rostratum life history mechanism of endangerment
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Biological traits and life history of Pagiophloeus tsushimanus(Coleoptera:Curculionidae),a weevil pest on camphor trees in China
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作者 Cong Chen Congcong Zhang +6 位作者 Shouyin Li Han Zhu Binqi Fan Yan Wang Peng Su Yangyang Han Dejun Hao 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第5期1979-1988,共10页
Cinnamomum camphora(L.)J.Presl.(Laurales:Lauraceae)is widely cultivated as an important landscape tree species in many urban areas in South China,especially in Shanghai City.Pagiophloeus tsushimanus Morimoto has becom... Cinnamomum camphora(L.)J.Presl.(Laurales:Lauraceae)is widely cultivated as an important landscape tree species in many urban areas in South China,especially in Shanghai City.Pagiophloeus tsushimanus Morimoto has become a destructive insect pest of C.camphora plantations in Shanghai,but the biological and ecological traits of this pest remain largely unknown.In this study,we investigated the damage and life history and determined the larval instar of P.tsushimanus.The results indicated that P.tsushimanus is a monophagous weevil pest,and C.camphora is the unique host tree species.C.camphora plantations in all administrative districts of Shanghai have been seriously damaged by P.tsushimanus.Adults often aggregate for feeding on the tender bark of twigs and occasionally on newly emerged buds.After experiencing damage,the twigs shrink and crack and the buds will shrink.Adults tend to repeatedly mate and oviposit,and all females lay single eggs at a time.Eggs will be covered with a mixture of secretions and wood chips by female adults.Larvae(1 st-2 nd instar)feed on the phloem,while 3 rd-5 th instar can bore into the phloem and the cambium.Massive tunnels,including three shapes(inverted"L",inverted"T",and inverted"Z"),were observed in the trunk of each tree,and resulted in swelling of the outer bark.P.tsushimanus has one life cycle per year in Shanghai.Both adults and larvae(3 rd-5 th instar)overwinter from early November to early April.Adults overwinter in grooves on the underside of branches or at branch nodes,and larvae overwinter in tunnels.Five larval instars of P.tsushimanus were determined according to Dyar’s and Crosby’s rules.The biological traits and life history of P.tsushimanus have been identified and can provide guidance in terms of pest control and plantation management. 展开更多
关键词 Cinnamomum camphora Damage traits life cycle Dyar’s rule Head capsule width
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Covariation in Insular Life-history Traits of the Rice Frog(Fejervarya limnocharis)in Eastern China
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作者 Feng XU Gregory H.ADLER Yiming LI 《Asian Herpetological Research》 SCIE 2013年第1期28-35,共8页
Although shifts in life-history traits of insular vertebrates, as compared with mainland populations, have been observed in many taxa, few studies have examined the relationships among individual life-history traits o... Although shifts in life-history traits of insular vertebrates, as compared with mainland populations, have been observed in many taxa, few studies have examined the relationships among individual life-history traits on islands. Lifehistory theory also predicts that there is a trade-off between body size and reproductive effort, and between egg size and clutch size. We surveyed the rice frog, Fejervarya limnocharis, on 20 islands within the Zhoushan Archipelago and two nearby sites on the mainland of China to compare differences in life-history traits and to explore relationships among those traits. Rice frog females reached a greater body size on half of the smaller islands among the total 20 surveyed islands, and larger egg size, decreased clutch size and reduced reproductive effort on most of the islands when compared to the two mainland sites. Insular body size was negatively correlated with reproductive effort. There was a negative correlation between egg size and clutch size. Results suggest that life-history theory provides a good explanation for co-variation between body size and reproductive effort, and between egg size and clutch size in rice frogs on the islands. 展开更多
关键词 island syndrome life-history traits trade-off body size egg size clutch size reproductive effort
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Textual research on Xu Chunfu's life
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作者 Ju-Yi Wang Hui Huang +1 位作者 Lin-Na Wu Wen-Qing Wu 《History & Philosophy of Medicine》 2024年第3期9-15,共7页
Xu Chunfu was a famous medical expert in the Ming Dynasty, who authored the Gu Jin Yi Tong Da Quan and the Yi Xue Zhi Nan Jie Jing Liu Shu. This paper uses the Xu family genealogy, literature catalog, historical recor... Xu Chunfu was a famous medical expert in the Ming Dynasty, who authored the Gu Jin Yi Tong Da Quan and the Yi Xue Zhi Nan Jie Jing Liu Shu. This paper uses the Xu family genealogy, literature catalog, historical records to study the Xu family’s life and deeds. Xu Chunfu was born in the second year of the Jiajing reign of the Ming Dynasty (1523) and passed away in the 24th year of the Wanli reign of the Ming Dynasty (1596). He served as an official in the Tai Hospital for about 20 years. His work Gu Jin Yi Tong Da Quan was written around the 43rd year of the Jiajing reign of the Ming Dynasty (1556), with a lower limit of the fifth year of the Longqing reign of the Ming Dynasty (1571), and the initial engraving time was not earlier than the eighth year of the Wanli reign of the Ming Dynasty (1580). This paper corrects the shortcomings and errors in previous research, and provides a comprehensive and systematic examination of Xu Chunfu’s life and works. 展开更多
关键词 Xu Chunfu life history biographical verification Gu Jin Yi Tong Da Quan Yi Xue Zhi Nan Jie Jing Liu Shu Genealogy of the Xu Clan in Qimen Tangtou Yinan and Chiling
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Re-identifying Grateloupia yangjiangensis(Rhodophyta, Halymeniaceae) based on morphological observations, life history and rbcL sequence analyses 被引量:10
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作者 WANG Hongwei GUO Shaoru +3 位作者 ZHANG Xiaoming ZHAO Dan ZHANG Wen LUAN Rixiao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第4期77-84,共8页
On the basis of morphological observations, life history and molecular phylogeny, Grateloupia yangjiangensis, which is similar to G. filicina, G. orientalis, G. catenata, and G. ramosissima in appearance, was re-exami... On the basis of morphological observations, life history and molecular phylogeny, Grateloupia yangjiangensis, which is similar to G. filicina, G. orientalis, G. catenata, and G. ramosissima in appearance, was re-examined. The results are as follows:(1) the auxiliary-cell ampullae of G. yangjiangensis were of Grateloupia type, thalli was fleshy and gelatinous in texture, and the erect axes were compressed; the cortex was 0.25–0.30 mm thick, consisting of five to seven outer layers, and there were five inner layers of triangular or stellate cells;(2) there was no filamentous stage in the development of the carpospores;(3) the ribulose-1,5-bisphosphate carboxylase/oxygenase gene(rbcL) sequence of four G. yangjiangensis examined showed that there was no intergeneric divergence among them, and for the phylogenetic tree, four sequences of G. yangjiangensis formed a single monophyletic subclade within the large Grateloupia clade of Halymeniaceae. In conclusion, G. yangjiangensis was a single species within the genus Grateloupia. This research provided criterion for identification and cultivation of G. yangjiangensis. 展开更多
关键词 Grateloupia yangjiangensis HALYMENIACEAE RHODOPHYTA morphological observations life history RBCL
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Temperature Effect on the Life History of Three Types of Brachionus calyciflorus Females 被引量:4
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作者 席贻龙 黄祥飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第2期192-197,共6页
The effect of temperature on the life history characteristics of amictic females (AF), unfertilized mictic females (UMF) and fertilized mictic females (FMF) in Brachionus calyciflorus was studied with replicated indiv... The effect of temperature on the life history characteristics of amictic females (AF), unfertilized mictic females (UMF) and fertilized mictic females (FMF) in Brachionus calyciflorus was studied with replicated individual cultures at 20℃,25℃ and 30℃, and with algae Scenedesmus obliquus for their food. There were highly significant effects of both temperature and female type, independently and interactively, on the duration of juvenile and post-reproduction periods, and the number of eggs produced by the rotifer per life cycle. Among all the temperature-female type combinations, all the juvenile periods of FMF, and the post-reproduction periods of UMF and FMF at 20℃, were the longest, and the number of eggs produced by an UMF at 30℃ was the highest. There were highly significant effects of both temperature and female type on the duration of the reproduction period, but no clear correlation was observed between temperature and female type. The reproduction period of AF was longer than that of UMF and FMF. Only temperature influenced significantly the mean life-span of the three types of females. The duration of juvenile, reproduction and post-reproduction periods as well as the life-span of the three types of females were all reduced very significantly with rise of temperature, but the rates of reduction varied with female type. Among the three types of females, the number of eggs produced per life cycle by an UMF was the highest, and that of a FMF was the lowest. A significant relationship between the number of eggs produced per life cycle and temperature was observed only in the UMF. 展开更多
关键词 Brachionus calyciflorus ROTIFER life history TEMPERATURE female type
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Significant Effects of Fishing Gear Selectivity on Fish Life History 被引量:4
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作者 LIANG Zhenlin SUN Peng +2 位作者 YAN Wei HUANG Liuyi TANG Yanli 《Journal of Ocean University of China》 SCIE CAS 2014年第3期467-471,共5页
Over the past few decades, extreme changes have occurred in the characters of exploited fish populations. The majority of these changes have affected the growth traits of fish life history, which include a smaller siz... Over the past few decades, extreme changes have occurred in the characters of exploited fish populations. The majority of these changes have affected the growth traits of fish life history, which include a smaller size-at-age, an earlier age-at-maturation and among others. Currently, the causes of these life history traits changes still require systematic analyses and empirical studies. The explanations that have been cited are merely expressed in terms of fish phenotypic adaptation. It has been claimed that the original traits of fish can be recovered once the intensity of exploitation of the fish is controlled. Sustained environmental and fishing pressure will change the life history traits of most fish species, so the fish individual's traits are still in small size-at-age and at earlier age-at-maturation in exploited fish populations. In this paper, we expressed our view of points that fishing gear has imposed selectivity on fish populations and individuals as various other environmental factors have done and such changes are unrecoverable. According to the existing tend of exploited fish individual's life history traits, we suggested further researches in this field and provided better methods of fishery management and thereby fishery resources protection than those available early. 展开更多
关键词 size composition life history fishing gear selectivity fishery management
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Effects of Microcystis aeruginosa on life history of water flea Daphnia magna 被引量:3
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作者 刘利平 李慷 +3 位作者 陈桃英 戴习林 江敏 James S. DIANA 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第4期892-897,共6页
Cyanobacterial blooms in eutrophic freshwater systems are a worldwide problem, creating adverse effects for many aquatic organisms by producing toxic mierocystins and deteriorating water quality. In this study, microc... Cyanobacterial blooms in eutrophic freshwater systems are a worldwide problem, creating adverse effects for many aquatic organisms by producing toxic mierocystins and deteriorating water quality. In this study, microcystins (MCs) in Microcystis aeruginosa, and Daphnia magna exposed to M. aeruginosa, were analyzed by HPLC-MS, and the effects of M. aeruginosa on D. magna were investigated. When D. magna was exposed to M. aeruginosa for more than 2 h, Microcystin-LR (MC-LR) was detected. When exposed to 1.5× 10^6, 3× 10^6, 0.75× 10^7, and 1.5× 10^7 cell/mL of M. aeruginosa for 96 h, average survival of D. magna for treatments were 23.33%, 33.33%, 13.33%, 16.67%, respectively, which were significantly lower than the average 100% survival in the control group (P 〈 0.05). The adverse effects ofM. aeruginosa on body length, time for the first brood, brood numbers, gross fecundity, lifespan, and population growth olD. magna were density-dependent. These results suggest that the occurrence of M. aeruginosa blooms could strongly inhibit the population growth of D. magna through depression of survival, individual growth and gross fecundity. In the most serious situations, M. aeruginosa blooms could undermine the food web by eliminating filter-feeding zooplankton, which would destroy the ecological balance of aquaculture water bodies. 展开更多
关键词 Microcvstis aeruginosa Daphnia magna life history TOXICITY
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Life-history dependent relationships between plasma alkaline phosphatase activity and body condition in male Eurasian Tree Sparrows 被引量:1
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作者 Yuliang Zhao Lingjuan Gong +3 位作者 Baohua Zhao Xuebin Gao Yuefeng Wu Dongming Li 《Avian Research》 CSCD 2017年第3期163-167,共5页
Background: In temperate-breeding birds, individuals must adjust their physiological states from one life-history stage to another in response to changing conditions to maximize ecological fitness. Previous evidences ... Background: In temperate-breeding birds, individuals must adjust their physiological states from one life-history stage to another in response to changing conditions to maximize ecological fitness. Previous evidences have shown that body mass, size-corrected mass(SCM), and hematocrit(Hct) could be used as estimates of the energetic state of individuals to illustrate life-history trade-offs and individual quality in field physiology. Plasma alkaline phosphatase(ALP) plays critical roles in regulating the metabolism of energy but very limited information is known on its link with body mass or Hct.Methods: We determined the changes of plasma ALP levels in both early breeding and wintering stages of male Eurasian Tree Sparrows(Passer montanus), and examined the relationships between ALP and body mass, SCM, and Hct of the birds.Results: Our study showed that(1) in male Eurasian Tree Sparrows, body mass did not vary with life-history stage but plasma ALP activity significantly increased in the wintering stage compared to the breeding stage;(2) ALP activity was not correlated with individual body mass but was positively correlated with individual SCM and Hct. Such positive correlations, however, only occurred in the wintering but not in the breeding stages.Conclusions: Our results suggest that plasma ALP activities in free-living birds can be used as one of the indicators o body condition or nutritional status for analyzing individual variation in the wintering but not in the breeding stages. The life-history dependent relationships between plasma ALP activity and body condition may contribute to our better understanding of the trade-off between individual survival and reproduction in free-living animals. 展开更多
关键词 Alkaline phosphatase Size-corrected mass HEMATOCRIT Passer montanus life history Trade-off
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Sexual Fusion and Life History of Scytosiphon lomentaria (Scytosiphonaceae, Phaeophyceae) in Dalian, China 被引量:1
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作者 LI Xiaoli ZHANG Zeyu +1 位作者 DONG Shuanglin CAO Shuqing 《Journal of Ocean University of China》 SCIE CAS 2011年第2期170-176,共7页
Morphology and life history of a brown alga Scytosiphon lomentaria (Lyngbye) Link (Scytosiphonaceae, Phaeophyceae) were investigated from 2005 to 2009 in the coastal waters of Dalian, China. The erect thalli collected... Morphology and life history of a brown alga Scytosiphon lomentaria (Lyngbye) Link (Scytosiphonaceae, Phaeophyceae) were investigated from 2005 to 2009 in the coastal waters of Dalian, China. The erect thalli collected in the field were tubular, hollow, and commonly constricted at intervals. Ascocysts were presented. Plurilocular gametangia, which were positioned in continuous sori on the erect thallus surface, produced biflagellar gametes. Gametophytes were dioecious and gametes were nearly isogamous. Gametes fusion occurred in three types. Type one, female and male gametes fused directly while swimming; type two, female gamete settled first, with which a male one contacted and fused rapidly; type three, while settling adjacently, a male gamete's entire protoplast moved slowly into the previously settled female one, with only an empty cell membrane left. In culture zygotes developed into crustose sporophytes that formed unilocular sporangia. Biflagellar zoospores developed into erect thalli that formed plurilocular gametangia. The results indicated that a periodical heteromorphic alternation history with haploid gametophyte generation and diploid sporophyte generation exists in S. lomentaria of the Dalian populations. 展开更多
关键词 sexual fusion life history MORPHOLOGY Scytosiphon lomentaria
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Early development,life history and ecological habits of Grateloupia constricata Li et Ding 被引量:1
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作者 Yuanyuan Ding Yao Bian +3 位作者 Huina Wang Jing Liu Jingrui Li Hongwei Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第10期155-161,共7页
As the largest genus of Halymeniaceae,Grateloupia has been widely reported.Here,we observed the life history and early development of Grateloupia constricata Li et Ding and investigated the effects of temperature,irra... As the largest genus of Halymeniaceae,Grateloupia has been widely reported.Here,we observed the life history and early development of Grateloupia constricata Li et Ding and investigated the effects of temperature,irradiance,and photoperiod on the discoid crust and sporeling development of G.constricata under laboratory conditions.We observed that the type of carpospore development was“mediate discal type”.The life history included homotypic gametophyte(haploid),carposporophyte(diploid),and tetrasporophyte(diploid),with typical isomorphic alternation of generations.The results of double factorial analysis showed that both single factorial effects and interaction among temperature,photoperiod,and irradiance were obviously significant on the discoid crust and sporeling development.Furthermore,we found that the optimum combination of condition for the early growth and development of G.constricata was temperature 20°C,irradiance 80μmol photons/(m^2·s)and photoperiod 16L:8D.This study provides the theoretical basis and technical support for the conservation of the Grateloupia germplasm,artificial breeding,large-scale cultivation and sustainable development. 展开更多
关键词 carpospore life history alternation of generations TEMPERATURE IRRADIANCE PHOTOPERIOD
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Life History Research in Education
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作者 何亚平 张燕 《海外英语》 2011年第13期369-372,共4页
Life history research,as one of the most powerful research methods in sociology,brings some re-freshened air into interpretive research.In this paper,the development of life history research,from modernism to postmode... Life history research,as one of the most powerful research methods in sociology,brings some re-freshened air into interpretive research.In this paper,the development of life history research,from modernism to postmodernism,from life story to life history,is firstly illustrated.Then the process of conducting life history research is analyzed specifically,which is followed by its unique strengths.Finally,its issues,its general issues and its special issues in Chinese context,are critically examined. 展开更多
关键词 life history RESEARCH development process UNIQUE strengths ISSUES
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Study on Life History and Daily Rhythm of Gilpinia yongrenica
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作者 Liu Tongtong Yang Zaihua 《Plant Diseases and Pests》 CAS 2019年第5期16-19,共4页
The life history and adult daily rhythm of Gilpinia yongrenica Xiao et Huang in Guizhou Province were observed and recorded.The results showed that there were three generations of G.yongrenica in Guizhou area;the firs... The life history and adult daily rhythm of Gilpinia yongrenica Xiao et Huang in Guizhou Province were observed and recorded.The results showed that there were three generations of G.yongrenica in Guizhou area;the first generation occurred from late March to middle July;the second generation occurred from early June to middle October;and the third generation occurred from middle September to late April.The ratio of male to female was 5.75∶1,and the emergence rate was 88.25%.The emergence of adults changed significantly with time,and the peak emergence period was at 12:00-13:00.The resting behavior accounted for the largest proportion in daily time distribution of adult behavior;followed by moving behavior and spawning behavior;and the mating behavior accounted for the smallest proportion.The moving behavior mainly occurred during the daytime,which reached the peak at 8:00-11:00.The resting behavior mainly occurred at 19:00-7:00,with the maximum reaching 100%.The mating behavior was concentrated at 12:00-13:00,which reached the peak at 13:00(19.5%).The spawning behavior mainly occurred at 14:00-15:00,and reached the peak at 14:00(42.1%). 展开更多
关键词 Gilpinia yongrenica life history DAILY RHYTHM
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Life Strategy Traits of the Liana Sericostachys scandens Spreading in the Montane Forests in the Kahuzi-Biega National Park (DR Congo)
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作者 Masumbuko Ndabaga Céphas Herpigny Basile +3 位作者 Barbier Nicolas Habiyaremye Muhashy Franois Lejoly Jean Meerts Pierre 《Journal of Mountain Science》 SCIE CSCD 2012年第5期665-675,共11页
Sericostaehys seandens is a monocarpic and heliophilous liana, native in tropical African forests. In the montane forests of the Kahuzi-Biega National Park (KBNP) (East of DR Congo), it has been expanding very str... Sericostaehys seandens is a monocarpic and heliophilous liana, native in tropical African forests. In the montane forests of the Kahuzi-Biega National Park (KBNP) (East of DR Congo), it has been expanding very strongly for a decade, and is currently considered as having negative impacts on biodiversity conservation. In this paper, we test if S. scandens differs from three co-occurring, native, non spreading lianas (Gouania longispicata, Tacazzea apiculata and Adenia bequaertii) for functional traits which might influence plant expansion. For leaf traits (SLA, dry matter content, nitrogen concentration), S. scandens did not show extreme values compared to those of the three other lianas. In contrast, S. scandens had much higher biomass allocation to sexual reproduction. It also differs from the three other lianas for its reproductive strategy that combines both vegetative propagation and sexual reproduct/on, and propagule dispersal by wind. Moreover, S. scandens has larger leaves and a greater number of lateral branches per unit stem length. It is argued that the particular combination of functional traits exhibited by S.scandens may in part explain its propensity to behave as an opportunistic weed in the disturbed areas in the montane forests of Kahuzi-Biega. 展开更多
关键词 life strategy Sericostachys seandens montane forest Kahuzi-Biega National Park functional traits Native expanding species.
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