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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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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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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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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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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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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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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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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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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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An Insight Into the Promise and Problems of Combining Life History and Grounded Theory Research
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作者 Bronwyn Betts 《Chinese Business Review》 2013年第2期84-92,共9页
This paper describes the research carried out in partial fulfilment of the degree of doctor of education. The study was qualitative in nature with a phenomenological interpretive paradigm dominating the philosophical ... This paper describes the research carried out in partial fulfilment of the degree of doctor of education. The study was qualitative in nature with a phenomenological interpretive paradigm dominating the philosophical approach. The research methods adopted combined life story and grounded theory. As far as the author has been able to determine there are very few, if any studies which have applied this approach specifically to this area of research which investigated the influence life history has on attitude to lifelong learning. Twenty five respondents were interviewed in face-to-face informal interviews. The main aim was to elicit the respondent's subjective interpretation of the interaction between school, family, work, and learning within their lives. The researcher was then able to identify when they occurred and what or who made them particularly meaningful. This paper describes how initial decisions were made regarding the substantive area for the research. Sampling technique and method for collecting the data is discussed and a worked example is given of how the data was analysed. It is intended that this paper will give an insight into the challenge of combining these two much debated methods of research. The empirical data lead to some interesting findings which educators and policy makers will find helpful in order to strengthen the school, college, and workplace interface. 展开更多
关键词 life history grounded theory METHODOLOGY FAMILY SCHOOL LEAMING
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Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged darkness differ between annual and perennial flax(Linum L.)
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作者 Kenyon J. Nisbett Abida Alokozai +2 位作者 Su Hyun Elizabeth Ko G. Adam Mott Jason C.L. Browna 《Oil Crop Science》 CSCD 2024年第2期121-130,共10页
Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 years.As proposed by the Disp... Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 years.As proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,with perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple seasons.Such differential investment may be particularly important during periods of exogenous stress,which are known to accelerate biomolecular damage.The present study evaluated this hypothesis using annual and perennial flax(Linum L.)subjected to two exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged darkness.As chlorophyll has been shown to exhibit degradation in response to changes in environmental conditions,we utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our hypotheses.We predicted that i)perennials would exhibit a slower rate of chlorophyll degradation during exposure to exogenous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following such exposure compared to annuals.Chlorophyll levels before,during,and after exposure to both exogenous stressors were measured in two separate trails,once using image colour analysis and once using spectrophotometry.While chlorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following such exposure were significantly higher in perennials,as predicted.When plants were subjected to complete prolonged darkness,chlorophyll degradation rates were significantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,chlorophyll resynthesis rates did not consistently differ between annuals and perennials,though they tended to be higher in the latter,as predicted.Overall,our study illuminates that evolutionary transitions between life history strategies in plants have been accompanied by physiological modifications to chlorophyll dynamics that permit perennial species to better maintain chlorophyll levels—and thus photosynthetic energy acquisition-in the face of exogenous stressors,which likely underlies their capacity to survive for multiple growing seasons.Future studies should explore whether other key biomolecules(e.g.,proteins,DNA)are also better maintained in perennial plants,especially in the face of exogenous stress. 展开更多
关键词 Ageing life history Maximum lifespan Oxidative stress Somatic maintenance
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Population life tables for the invasive fall armyworm,Spodoptera frugiperda fed on major oil crops planted in China 被引量:10
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作者 HE Li-mei WU Qiu-lin +1 位作者 GAO Xi-wu WU Kong-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第3期745-754,共10页
The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous ... The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous herbivore is especially important for making control strategy.Here,after FAWs were fed three important oil-bearing crops(oilseed rape,soybean and sunflower)planted in China and resultant population parameters were compared using the age-stage,two-sex life table method,survival of larvae on soybean was significantly lower than that on oilseed rape and sunflower.Developmental duration of larvae on soybean was also the longest(23.3 days).The highest pupation rate was recorded on sunflower.The highest pupal mass(0.19 g)was attained on oilseed rape,significantly higher than on the other host plants;the lowest mass was on soybean(0.15 g).On soybean,oilseed rape and sunflower,respectively,the average generation period was 42.21,39.10 and 40.44 d;the intrinsic rate of increase(r)was 0.0844,0.1041 and 0.1134;the finite rate of increase(λ)was 1.0881,1.1098 and 1.1202.While the most suitable host plant overall was sunflower,S.frugiperda completed development and increased its population on all three host plants.Thus,soybean,oilseed rape and sunflower were all suitable for FAW,and population monitoring and management of FAW in these crops should be increased. 展开更多
关键词 developmental duration FECUNDITY life history oil-bearing crops BIOLOGY invasion biology
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Age structure and static life tables of the endangered Juniperus phoenicea L. in North Sinai Mountains, Egypt:implication for conservation 被引量:5
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作者 Emad A.FARAHAT 《Journal of Mountain Science》 SCIE CSCD 2020年第9期2170-2178,共9页
Studying the population ecology of endangered plants provides important baseline information for its monitoring and conservation.Juniperus phoenicea L.is an endangered species in arid ecosystems in Africa and the Midd... Studying the population ecology of endangered plants provides important baseline information for its monitoring and conservation.Juniperus phoenicea L.is an endangered species in arid ecosystems in Africa and the Middle East.The static life tables,survival curve and age structure of J.phoenicea populations from two mountains in North Sinai,Egypt(Gabal(G.)El-Halal and G.El-Maghara)were investigated.In each mountain,fifteen plots were selected,and field measurements such as stand density,tree height,and crown diameter were conducted.Moreover,44 trees were cored and crossdated according to standard dendrochronological procedures.The results showed that the tree ages ranged from 50 to 262 years at G.El-Halal and 96 to431 years at G.El-Maghara.Mature J.phoenicea individuals dominated the study area,with only a few individuals being younger than 100 years.Moreover,seedling recruitment was extremely limited.Since the studied J.phoenicea populations showed high mortality rates among both old and young individuals,there is an imminent need for establishing a conservation program to prevent its extinction in the future.Therefore,management and conservation efforts should be made to minimize human disturbance and protect the relic habitats of this endangered species at its southern distribution limits in Africa. 展开更多
关键词 Juniperus phoenicea Age distribution life history MORTALITY Endangered plant SINAI
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Neighborhood diversity structure and neighborhood species richness effects differ across life stages in a subtropical natural secondary forest 被引量:2
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作者 Haonan Zhang Shuifei Chen +5 位作者 Xiao Zheng Xiaomin Ge Yao Li Yanming Fang Peng Cui Hui Ding 《Forest Ecosystems》 SCIE CSCD 2022年第6期790-801,共12页
Natural secondary forest has a strong capacity to regrow naturally and recover biodiversity rapidly on abandoned lands.However,at the neighborhood scale,which can truly reflect the facilitative or competitive interact... Natural secondary forest has a strong capacity to regrow naturally and recover biodiversity rapidly on abandoned lands.However,at the neighborhood scale,which can truly reflect the facilitative or competitive interactions among individual plants,the local diversity spatial structure in secondary forest and the feedback effects of neighborhood diversity on natural regeneration remain unclear,and this may be the key to properly understand the mechanisms of natural secondary forest species diversity recovery.To this end,this study established a dynamic plot in a rehabilitated secondary forest after disturbance and conducted a comprehensive survey of 68,336 individual plants with repeated measurements at 5-year interval to assess the characteristics of neighborhood diversity structure across life history stages and link the neighborhood species richness(NSR)effect translated by species interactions at species diversity structure with individual trees recruitment/mortality in secondary forest regeneration.The results showed that,compared with tropical and temperate natural forests,a higher proportion of diversity accumulators and a lower proportion of repellers in subtropical secondary forests resulted in neighborhood diversity structures characterized by heterospecific or high-diversity patches,which are beneficial to the maintenance or restoration of biodiversity.As an important supplement to the research on the relationship between diversity and productivity,our findings show a positive diversity-survival relationship in subtropical secondary forests.Importantly,we observed that the neighborhood diversity structure exhibited a trend of accumulator-dominated to neutral-dominant changes with life stage from sapling to adult,which,in turn,determined the direction and strength of NSR effects on recruitment/mortality.Specifically,diverse local neighborhoods at a later successional stage characterized with‘neutral’species-species interactions can act as a‘welfare net’by offering favorable microhabitats for the most vulnerable recruitments or saplings,i.e.,the NSR effects that promoted individual recruitment/survival in our study.These results not only enrich our understanding of the biodiversity-productivity-survival relationship but also highlight the importance of retaining latesuccessional species of native trees in intensive forest production or in situ conservation policies. 展开更多
关键词 Secondary forest restoration Individual species area relationship Diversity accumulator species Neighborhood species richness effect life history stages Heterospecific crowding
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Effects of Life Histories on Genome Size Variation in Squamata
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作者 Chuan CHEN Long JIN +1 位作者 Ying JIANG Wenbo LIAO 《Asian Herpetological Research》 SCIE CSCD 2021年第3期289-294,共6页
Genome size changes significantly among taxonomic levels,and this variation is often related to the patterns shaped by the phylogeny,life histories and ecological factors.However,there are mixed evidences on the main ... Genome size changes significantly among taxonomic levels,and this variation is often related to the patterns shaped by the phylogeny,life histories and ecological factors.However,there are mixed evidences on the main factors affecting molecular evolution in animals.In this study,we used phylogenetic comparative analysis to investigate the evolutionary rate of genome size and the relationships between genome size and life histories(i.e.,hatchling mass,clutch size,clutches per year,age at sexual maturity,lifespan and body mass)among 199 squamata species.Our results showed that the evolutionary rate of genome size in Lacertilia was significantly faster than Serpentes.Moreover,we also found that larger species showed larger hatchling mass,more clutches per year and clutch size and longer lifespan.However,genome size was negatively associated with clutch size and clutches per year,but not associated with body mass we looked at.The findings suggest that larger species do not possess the evolution of large genomes in squamata. 展开更多
关键词 genome size body mass evolutionary rate life histories
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Generation and Application of A Standardized Load-Time History to Tubular T-joints in Offshore Platforms
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作者 李珊珊 崔维成 《China Ocean Engineering》 SCIE EI CSCD 2015年第5期633-648,共16页
Marine structures are mostly made of metals and always experience complex random loading during their service periods. The fatigue crack growth behaviors of metal materials have been proved from laboratory tests to be... Marine structures are mostly made of metals and always experience complex random loading during their service periods. The fatigue crack growth behaviors of metal materials have been proved from laboratory tests to be sensitive to the loading sequence encountered. In order to take account of the loading sequence effect, fatigue life prediction should be based on fatigue crack propagation(FCP) theory rather than the currently used cumulative fatigue damage(CFD) theory. A unified fatigue life prediction(UFLP) method for marine structures has been proposed by the authors' group. In order to apply the UFLP method for newly designed structures, authorities such as the classification societies should provide a standardized load-time history(SLH) such as the TWIST and FALSTAFF sequences for transport and fighter aircraft. This paper mainly aims at proposing a procedure to generate the SLHs for marine structures based on a short-term loading sample and to provide an illustration on how to use the presented SLH to a typical tubular T-joint in an offshore platform based on the UFLP method. 展开更多
关键词 standardized load-time history(SLH) unified fatigue life prediction(UFLP) method fatigue crack propagation(FCP) theory tubular T-joint
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