A comparative analysis of recruitment variability in North Atlantic flatfishes — testing the species range hypothesis     

William C. Leggett  Kenneth T. Frank 《Journal of Sea Research》1997,37(3-4)

The hypothesis that recruitment variation in flatfishes should be most variable at the northern edge of the species range, least near the centre of the range, and intermediate near the southern limit was tested using stock and recruitment data generated from sequential population analysis for several different flatfish stocks involving four species (plaice Pleuronectes platessa, sole Solea vulgaris from the eastern Atlantic, American plaice Hippoglossoides platessoides, and yellowtail flounder Limanda ferruginae from the western Atlantic). Several groundfish species have been found to conform to this so-called species range hypothesis with the suggestion that density-independent processes predominate at the edges of the distributional range and density-dependent processes dominate in the centre of the range. Our results were generally inconsistent with the hypothesis: the coefficient of variation (CV) of recruitment for plaice in the eastern Atlantic was independent of latitude, the CV of recruitment for sole exhibited a dome-shaped relationship with latitude with the highest CVs occurring at the mid-point of the range, and the CV of recruitment for the western Atlantic stocks exhibited a monotonic decrease with latitude. We extended our latitudinal analyses by assessing both the degree of dependency of recruitment on spawning stock biomass and the spatial and temporal scales of variability in recruitment and pre-recruit survival for the eastern Atlantic stocks. In general our analysis revealed no evidence of a strong stock and recruitment relationship for any of the stocks examined, and previously published analyses revealed no such patterns with latitude. Analysis of both de-trended recruitment and pre-recruit survival time series over the species ranges of sole and plaice revealed strong positive correlations among adjacent stocks and inverse correlations among stocks at the extremes of the range. Recruitment variation in the flatfish stocks examined appears to be dominated by density-independent factors, operating at a local scale, on the egg and larval stages.  相似文献   

Combined Effects of Temperature and Salinity on the Zoeal Development of the Crab Liocarcinus puber (Decapoda: Portunidae)     

M. Nagaraj 《Marine Ecology》1992,13(3):233-241

Abstract. Larval development of the crab Liocarcinus puber was studied from hatching to the megalopa stage under 12 different temperature and salinity combinations, 10°C, 15°C, and 20°C (T): 20, 25, 30, and 35% (S), with a view to establishing optimum conditions for zoeal development. High larval mortalities were recorded at 10°C in all the experimental salinities, indicating the sensitivity of the larvae to low temperatures. Highest zoeal survival was obtained in the higher salinity and temperature combinations. First zoeae completed their development in all T-S combinations tested, while successive stages showed increased sensitivity and suffered high mortalities in lower salinities at 15° and 20°C and in all salinities at 10°C. The duration of zoeal development decreased with increasing temperature, whilst the lower salinities delayed development. Q₁₀ values did not differ much at higher salinities, with values ranging from 1.5 to 2.6.  相似文献   

The effect of temperature and salinity on survival and growth of Crangon uritai (Decapoda: Crangonidae) larvae reared in the laboratory     

Hui Yu Li  & Sung Yun Hong 《Marine Ecology》2007,28(2):288-295

Larvae of the decapod Crangon uritai were reared in the laboratory in a factorial experiment employing three temperatures (9, 12 and 15 °C) and three salinities (29‰, 32‰ and 35‰) from hatching to the post‐larval stage. The effects of temperature and salinity on survival, intermolt period (IP) and molt increment (MI) were investigated. Larvae from one brood were subdivided into groups of 20 and reared in glass bowls containing filtered sea‐water at a number of temperature–salinity combinations. The reared larvae were transferred daily to the clean bowls prepared with newly hatched Artemianauplii, and number of molts and mortality within each bowl were recorded. The zoeal size (carapace length) was determined from exuvia and dead larvae, and the IP was also recorded. Larvae of C. uritai completed larval development only at 15 °C temperature. The first zoeal stage completed their development at all temperature–salinity combinations and exhibited the highest survival rate. IP at each stage increased with increasing size and greatly decreased with increasing temperature, and intermolt duration (range of days) increased with larval development especially at the lower temperature. Although the MI decreased with increasing size, it was little affected by temperature. This led to a better growth rate with increasing temperature.  相似文献   

Interannual changes in recruitment of the Atlantic salmon (Salmo salar) population in the River Oir (Lower Normandy, France): relationships with spawners and in-stream habitat     

Bagliniere  Jean-Luc; Marchand  Frederic; Vauclin  Vincent 《ICES Journal of Marine Science》2005,62(4):695-707

  相似文献   

Diet-induced differences in the essential fatty acid (EFA) compositions of larval Atlantic cod (Gadus morhua L.) with reference to possible effects of dietary EFAs on larval performance     

Cutts  C.J.; Sawanboonchun  J.; Mazorra de Quero  C.; Bell  J.G. 《ICES Journal of Marine Science》2006,63(2):302-310

  相似文献   

古尔班通古特沙漠沙丘主要灌木的种群数量动态     

朱春鸣  董治宝  刘铮瑶  肖南  杨军怀  冯淼彦 《中国沙漠》2021,41(2):129-137

种群数量动态的研究是认识种群的生存现状及发展动态的前提。通过对古尔班通古特沙漠固定沙丘、半固定沙丘和流动沙丘上主要固沙灌木的样地调查,分析了固沙灌木的年龄结构,建立了3种沙丘上固沙灌木的静态生命表和存活曲线。结果表明：（1）固沙灌木的存活个体数呈逐级递减的趋势,幼龄个体占有很高的比例;固定沙丘上梭梭（Haloxylon ammodendron）呈现Ⅰ型存活曲线,种群退化,白梭梭（Haloxylon persicum）呈现Ⅱ型存活曲线,种群稳定;（2）半固定沙丘上白梭梭呈Ⅱ型存活曲线,种群相对稳定;沙拐枣（Calligonum mongolicum）和油蒿（Artemisia ordosica）均呈现Ⅰ型存活曲线,种群处于退化状态;（3）流动沙丘上沙拐枣呈现Ⅲ型存活曲线,种群有较大的增长潜力,白梭梭呈现出Ⅱ型存活曲线,种群相对稳定,油蒿呈现出Ⅰ型存活曲线,种群处于不稳定的退化状态。  相似文献   

刺参4个不同选育品系幼参对低盐胁迫的耐受及生理生化响应     

侯西坦  廖梅杰  李彬  王印庚  张正  陈贵平  荣小军  孙金生  范瑞用 《海洋科学》2016,40(5):19-28

由于黄河口区域盐度偏低且不稳定,刺参(Apostichopus japonicus)的生长和存活受到严重威胁。为评估4个不同品系(日本刺参F2代RC-F2、抗病刺参F3代KC-F3、多刺刺参F2代DC-F2、青青刺参F1代QQ-F1)的低盐耐受力及其生理生化响应,本实验以青岛野生群体(QW)为对照,通过测定低盐胁迫下幼参的生长、存活以及非特异性免疫酶活力变化,评价了4个刺参不同选育品系对低盐的耐受状况。结果表明,在盐度17以下,除了QQ-F1表现为正生长,其他群体均为负生长。RC-F2、KC-F3、DC-F2、QQ-F1和QW的30天半致死盐度(LS50-30d)分别为15.02、15.19、16.48、14.26和15.13,QQ-F1显著低于其他4个群体;盐度14时,5个群体的半致死时间(ST50)分别为19.84 d、18.43 d、10.11 d、23.54 d和19.01 d,QQ-F1的ST50显著长于其他4个群体。在低盐胁迫时QQ-F1的ACP、AKP、SOD、LZM酶指标的下降幅度显著低于其他4个群体。不同选育群体的低盐耐受力排序为QQ-F1RC-F2QWKC-F3DC-F2,QQ-F1群体表现出良好的低盐耐受能力,在低盐度海域或盐度不稳定的海域具有良好的推广应用前景。本实验研究结果可为刺参健康养殖、良种性状评价、选育与推广等方面提供参考依据。  相似文献   

黑河流域中下游地区植物物种生存域研究   总被引：10，自引：0，他引：10  

徐恒力  汤梦玲马瑞 《地球科学》2003,28(5):551-556

基于对地境和根群的认识, 从系统论的角度首次提出了植物物种地境稳定层及生存域概念, 运用多种理化指标的组合状态对黑河中下游多年生植物物种地境稳定层层位进行了确定, 深度范围为40~100 cm.根据各典型植物物种地境稳定层的水土条件相应地圈划了它们的生存域, 并提出了黑河下游地区植被分布与地境关系的一些新认识.   相似文献   

FFECTSOFTEMPERATUREANDCa~(2+)ONTHELARVALDEVELOPMENTOFTHEDECAPODACRUSTACE     

黄勃  堵南山  赖伟 《中国海洋湖沼学报》2001,(3)

ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｉｍｐｏｒｔａｎｔｅｎｖｉｒｏｎｍｅｎｔａｌｆａｃｔｏｒｓａｆｆｅｃｔｉｎｇｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｏｆＥｒｉｏｃｈｅｉｒｓｉｎｅｎｓｉｓｌａｒ ｖａｅａｒｅｓａｌｉｎｉｔｙａｎｄｗａｔｅｒｔｅｍｐｅｒａｔｕｒｅ.ＤｉｆｆｅｒｅｎｔｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｓｔａｇｅｓｏｆＥｒｉｏｃｈｅｉｒｓｉｎｅｎｓｉｓｒｅｑｕｉｒｅｄｉｆｆｅｒｅｎｔｔｅｍｐｅｒａｔｕｒｅａｎｄｓａｌｉｎｉｔｙ (ＩｎｇｌｅａｎｄＡｎｄｒｅｗｓ,1 976) .Ｃａ2 +ｃｏｎｔｅ…  相似文献   

Impacts of CO₂-driven seawater acidification on survival, egg production rate and hatching success of four marine copepods   总被引：1，自引：0，他引：1  

ZHANG Dajuan  LI Shaojing  WANG Guizhong  GUO Donghui 《海洋学报(英文版)》2011,30(6):86-94

Ecological experiments were conducted to examine the effects of seawater containing elevated par- tial pressure of carbon dioxide (p CO2 800 × 10 -6 , 2 000 × 10 -6 , 5 000 × 10 -6 and 10 000 × 10 -6 ) on the survival and reproduction of female Acartia pacifica, Acartia spinicauda, Calanus sinicus and Centropages tenuiremis, which are the dominant copepods in the southern coastal waters of China. The results show that the effects of elevated p CO2 on the survival rates of copepods were species-specific. C. sinicus, which was a macro-copepod, had a higher survival rate (62.01%-71.96%) than the other three species (5.00%-26.67%) during the eight day exposure. The egg production rates of C. sinicus, A. spinicauda and C. tenuiremis were significantly inhibited by the increased p CO2 and the exposure time duration. There were significantly negative impacts on the egg hatching success of A. spinicauda and C. tenuiremis in the p CO2 2 000 × 10 -6 and 10 000 × 10 -6 groups, and, in addition, the exposure time had noticeably impacts on these rates too. This study indicates that the reproductive performances of copepods were sensitive to elevated p CO2 , and that the response of different copepod species to acidified seawater was different. Furthermore, the synergistic effects of seawater acidification and climate change or other pollutant stresses on organisms should be given more attention.  相似文献