拓林湾浮游桡足类生态研究

2000年7月至2001年7月的周年调查结果表明,粤东柘林湾浮游桡足类29属57种,其中,强额拟哲水蚤Paracalanus crassirostris和短角长腹剑水蚤Oithona brevicornis为优势种,合计占浮游桡足类总个体数的66.7%.柘林湾是一个浮游桡足类相对丰富的海湾,年均总个体数达5.4×10³ind.·m^-3.浮游桡足类的种类数和总个体数均表现为湾外大于湾内的平面分布格局,周年变化基本上为单峰型,高峰期位于5~10月,最低谷位于冬季1月。     

植食性浮游桡足类摄食生态学研究进展

由于浮游动物在调节海洋生物生产中的关键作用,对其摄食生态学的研究一直是海洋生态学研究的重点。总结了近年关于浮游动物主要类群－桡足类对浮游植物摄食的研究进展及其在海洋生态系统动力学研究中的重要意义。主要包括：影响植食怀桡足类摄食强度的主要因素,饵料对于桡足类种群变动的影响;现场测定桡足类摄食率的方法以及海洋生态系统动力学研究中需要关注的问题。     

胶州湾浮游桡足类时空分布

根据2003年1月至12月在胶州湾所获得的浮游生物样品,已鉴定浮游桡足类28种,幼虫、幼体6类.分析了该海区浮游桡足类的分布﹑时空变化及其与生态环境因子的关系,同相关历史资料进行了比较,结果表明,浮游桡足类的种类组成单纯,生态属性以暖温带、近岸低盐种类为主.浮游桡足类的丰度分布具明显的月份变化,高峰在7月份,为181.61个/m3,最低在12月份,为23.53个/m3,全年平均为71.42个/m3.浮游桡足类丰度的平面分布不均匀,最大丰度在5号站,为132.62个/m3,最小丰度在8号站,为40.45个/m3,丰度平面分布的变化趋势基本是湾北部海域大于湾南部海域.浮游桡足类丰度的时空分布,主要种类的季节更替,近20a来的变化趋势基本相同,高峰出现时间的差异,是受温度年季变化差异因素的影响.浮游桡足类丰度的时空分布与海水温度和盐度密切相关,与温度的关系更重要于与盐度的关系.并且用胶州湾的调察资料证实了浮游桡足类对浮游植物的依存关系,浮游植物为浮游桡足类的生长、繁衍提供了饵料.     

海洋浮游桡足类滞育的研究进展

海洋桡足类在海洋生态系统中占有重要的地位,其重要的生理现象一滞育是影响其种群数量变动的重要因子。本文对海洋桡足类滞育的形式、滞育的意义、滞育卵的孵化与发育以及诱导桡足类滞育的环境因子等方面的研究进行了综述,同时还提出了今后研究的方向,以期对桡足类滞育机制的研究提供新的思路。     

珠江口浮游桡足类的生态研究

根据2002～2003年珠江口12个航次的调查资料,分析了浮游桡足类种类组成、优势种演替和丰度的时空变化,探讨其影响因素。以表层盐度(S)变化将调查海域划分三个区域:I区(S<25)、Ⅱ区(2530)。结果表明:调查海域共出现桡足类65种,Ⅱ区和Ⅲ区的种类多于I区;桡足类的平均丰度为118ind·m^-3,三个区域之间的比较为Ⅱ区(165ind·m^-3)>I区(129ind·m^-3)>Ⅲ区(62ind·m^-3),春、夏季的丰度高于冬季;优势种有明显的时间和区域上的变化。I区9个航次的研究结果表明:I区桡足类种类较少;各月份之间的平均丰度差别大,由河口内往外呈增加趋势。盐度是影响珠江口桡足类种类组成和数量变化的主要因素。     

渤海浮游动物群落生态特点 Ⅱ.桡足类数量分布及变动

用1959年全国海洋普查浮游动物中网样品分析渤海浮游动物。尤其是中小型浮游动物的数量分布及变动特点。结果表明,渤海浮游动物全年平均丰度为3841ind／m^3,最大33756ind/m^3,最小6．5ind／m^3。其中桡足类年平均密度为3413ind／m^3,是数量的主要构成者。渤海浮游动物主要的高峰期出现在夏季,此外春、秋两季各自有一个小的高峰。春季峰主要是由双毛纺锤水蚤(Acartia bifilosa)的大量繁殖造成,秋季峰主要是由拟长腹剑水蚤(Oithona similis)构成。夏季峰是由于小拟哲水蚤(Paraclanus parvus)、强额拟哲水蚤(Paracalanus crassirostris)、拟长腹剑水蚤等多种桡足类和一些幼虫大量繁殖造成。渤海浮游动物季节演替比较明显。双毛纺锤水蚤、墨氏胸刺水蚤(Centropages mcmmurrichi)和中华哲水蚤(Calanus sinicus)是春季的优势种;小拟哲水蚤、拟长腹剑水蚤、近缘大眼剑水蚤(Corycaeus affinis)和太平洋纺锤水蚤（Acartia pacifica)是夏季的优势种;拟长腹剑水蚤、真刺唇角水蚤（Lubidocera euchaeta)等是秋季的优势种。数量的水平分布同温度的水平分布趋势基本一致。同盐度趋势相反。     

南海北部浮游桡足类对浮游植物的摄食压力

于2004年2月(冬季)和8月(夏季)在南海北部使用肠道色素法研究了浮游桡足类群落对浮游植物现存量的摄食压力。将底到表垂直拖网(网孔径200μm)获得的桡足类分为中型(>500μm)和小型(200~500μm)两个体长组。冬季:中型桡足类的丰度为103~2343(平均633)ind/m3,肠道色素为0.15~2.71(平均1.31)ng/ind,肠道排空率为0.011(A4)~0.019(C1)min-1,个体摄食率为3.13~58.48(平均28.36)ng/(ind.d),群落摄食率为1902~62369(平均18679)ng/(d.m3),对浮游植物生物量的摄食压力为每天0.25%~6.39%(平均3.04%)。小型桡足类的丰度为418~6250(平均1691)ind/m3,肠道色素为0.18~3.44(平均1.19)ng/ind,肠道排空率为0.012(A4)~0.016(C1)min-1,个体摄食率为3.67~70.04(平均24.34)ng/(ind.d),群落摄食率为1540~158561(平均44227)ng/(d.m3),对浮游植物生物量的摄食压力为每天0.44%~15.70%(平均6.59%)。浮游桡足类群体对浮游植物生物量的摄食压力为每天1.02%~20.10%(平均9.63%)。夏季:中型桡足类的丰度为111~1298(平均621)ind/m3,肠道色素分别为0.22~1.58(平均1.03)ng/ind,肠道排空率为0.017min-1,个体摄食率为5.52~39.92(平均25.95)ng/(ind.d),群落摄食率为4411~26667(平均12878)ng/(d.m3),对浮游植物生物量的摄食压力为每天0.23%~6.52%(平均2.52%)。小型桡足类的丰度为756~8804(平均2990)ind/m3,肠道色素含量为0.09~2.92(平均0.87)ng/ind,肠道排空率为0.020min-1,个体摄食率为2.73~87.77(平均26.26)ng/(ind.d),群落摄食率为9309~139817(平均47191)ng/(d.m3),对浮游植物生物量的摄食压力为0.86%~37.79%(平均10.99%)。浮游桡足类群体对浮游植物生物量的摄食压力为1.09%~39.95%(平均13.51%)。数据表明,2月份和8月份桡足类群体对浮游植物现存量的摄食压力较低,桡足类摄食不是南海北部浮游植物死亡的主要原因。     

桡足类滞育规律研究

首次提出用滞育指数对桡足类滞育能力进行相对量化处理 ,并对 10 2种桡足类的滞育能力同迁移能力、体长、栖息地之间的关系进行了数学分析 ,初步得出了滞育在桡足类中的分布规律 :在桡足类中滞育与迁移呈负相关 ,两者之间存在一定程度的置换 ;个体较小的桡足类一般具有较强的滞育能力和较弱的迁移能力 ,个体较大的桡足类一般具有较弱的滞育能力和较强的迁移能力 ;淡水桡足类一般比海洋桡足类具有较强的滞育能力。最后探讨了这种分布模式的成因     

三峡水库初次蓄水后干流库区桡足类的纵向分布与季节变化

作为大型水利工程, 三峡水库于2003年6月开始蓄水, 蓄水后库区水环境发生了变化。为了了解三峡水库水生态系统的演替规律, 同时为环境保护、渔业资源开发利用以及水环境管理提供理论基础, 我们对三峡水库第一阶段蓄水后桡足类的季节变化和空间分布进行了周年季节性研究。在三峡库区江津至茅坪的10个断面共采集到8种桡足类, 其中哲水蚤目2种、猛水蚤目1种、剑水蚤目5种, 北碚中剑水蚤(Mesocyclops pehpeiensis)、广布中剑水蚤(M. leuckarti)和汤匙华哲水蚤(Sinocalanus dorrii)分布较广。各样点种类数差异不大, 但组成上却有不同。桡足类种类组成、空间分布和密度具有明显的季节变化特征, 此外密度在水库的纵轴上也表现出明显的梯度分布, 越近大坝密度越高。     

海南岛西北沿岸海域浮游桡足类的分布及群落特征

为了解昌江沿岸海域生态系统的现状, 探讨海域环境因素对浮游动物的生存环境造成的影响。本文根据2008年11月至2009年7月在海南西部昌江沿岸水域21个测站、4个季度月调查所获的浮游桡足类样品数据, 对该海域浮游桡足类群落结构、分布、季节变化及影响因素进行了分析。本调查共鉴定出桡足类44种, 隶属4目17科24属, 其中秋季25种, 冬季23种, 春季22种, 夏季23种。本次调查共发现优势种6种, 分别是微刺哲水蚤(Canthocalanus pauper)、亚强次真哲水蚤(Subeucalanus subcrassus)、锥形宽水蚤(Temora turbinata)、刺尾纺锤水蚤(Acartia spinicauda)、椭形长足水蚤(Calanopia elliptica)和精致真刺水蚤(Euchaeta concinna), 优势种以近岸暖水种居多。浮游桡足类丰度季节变化明显: 冬季最高, 达409 ind./m³; 秋季次之, 为144 ind./m³, 春季为55 ind./m³, 夏季最低仅为17 ind./m³。其丰度的平面分布显示: 秋、冬季节分别在海区中部和南部形成明显密集区, 春、夏季节则大致呈现由外海向近岸逐渐递减的趋势。浮游桡足类的多样性指数(H')表现为夏季>春季>秋季>冬季, 春、夏季的均匀度指数(J')明显高于秋、冬季。本调查反映出该海区的桡足类群落具有热带—亚热带区系特征, 种类组成季节更替明显, 桡足类种群受海域水温和硅藻的影响明显, 受盐度影响不明显。     

Predator-induced diet vertical migration in a planktonic copepod

Predator evasion is the most commonly hypothesized reason fordiel vertical migrations undertaken by a wide variety of planktonicorganisms in lakes and seas, yet direct evidence remains elusive.We tested the predation hypothesis by exposing enclosed populationsof a marine copepod Acartia hudsonica to caged or free-rangingindividuals of their natural predator, the planktivorous fishGasterosteus aculeatus. After little more than a week, adultcopepods changed their vertical distribution and migration behaviordepending on the presence or absence of predation. Only free-rangingfish induced vertical migration in the copepod population. Cagedfish had no effect, indicating that vertical migration was nota simple chemically mediated response of copepods to the predator.Rather, copepods seemed to react to the presence of predatorsby other means, perhaps visual or mechanical stimuli, and toexhibit a downward escape response which, because encounterswith visually orienting fish occur chiefly in the daytime, effectivelylimited the copepods' occurrence in the upper water column tothe night-time hours. Alternatively, because fish imposed heavymortality on copepods, it is possible that selective predationaltered the proportions of individuals with fixed, geneticallydetermined migration behaviors. We suggest experiments to distinguishthese alternatives.     

柘林湾表层沉积物中的生物可利用磷

对2002年7月至2003年7月间采集的柘林湾表层沉积物样品中的总磷(TP)、有机磷(OP)及各形态无机磷进行分析。结果表明,各形态磷的空间分布与调查海区沉积物粒径有关,并受沿岸污水排放及近岸养殖排污等人为活动的影响。表层沉积物各形态磷的平面分布基本呈现为湾内(除S1、S7站外)高于湾外的总体趋势。无机磷中以自生磷(Au-P)为主要存在形态,占总磷的47.3%,有机磷(OP)含量次之,占总磷的19.5%,铁结合磷(Fe-P)最低。其中,生物可利用磷(包括Ex-P、Fe-P、OP和部分Au-P)占TP的35.7%~83.0%,在国内外海湾中处于较高水平。     

In situ egg production rate of the planktonic copepod Acartia steueri in Ilkwang Bay, southeastern coast of Korea

Egg production rate (EPR) of the copepod Acartia steueri wasinvestigated by in situ incubation in Ilkwang Bay, Korea. EPRranged from 3.8 to 10.1 eggs female^–1 d^–1, and weight-specificgrowth rate decreased with increasing body weight of the adultfemale.     

Hydrocarbon contamination decreases mating success in a marine planktonic copepod

The mating behavior and the mating success of copepods rely on chemoreception to locate and track a sexual partner. However, the potential impact of the water-soluble fraction of hydrocarbons on these aspects of copepod reproduction has never been tested despite the widely acknowledged acute chemosensory abilities of copepods. I examined whether three concentrations of the water-soluble fraction of diesel oil (0.01%, 0.1% and 1%) impacts (i) the swimming behavior of both adult males and females of the widespread calanoid copepod Temora longcornis, and (ii) the ability of males to locate, track and mate with females. The three concentrations of the water-soluble fraction of diesel oil (WSF) significantly and non-significantly affect female and male swimming velocities, respectively. In contrast, both the complexity of male and female swimming paths significantly decreased with increasing WSF concentrations, hence suggesting a sex-specific sensitivity to WSF contaminated seawater. In addition, the three WSF concentrations impacted both T. longicornis mating behavior and mating success. Specifically, the ability of males to detect female pheromone trails, to accurately follow trails and to successfully track a female significantly decreased with increasing WSF concentrations. This led to a significant decrease in contact and capture rates from control to WSF contaminated seawater. These results indicate that hydrocarbon contamination of seawater decreases the ability of male copepods to detect and track a female, hence suggest an overall impact on population fitness and dynamics.     

Feeding by an omnivorous planktonic copepod aetideus divergens Bradford

Aetideus divergens Bradford is representative of a large group of marine planktonic calanoid copepods which are omnivores or mixed feeders. Because very little quantitative information is available on the feeding behavior of these copepods, laboratory feeding experiments have been carried out with adult female A. divergens presented with various sizes and concentrations of diatoms and freshly hatched nauplii of Artemia. The copepod fed most efficiently on the largest size of diatom and on Artemia nauplii, but was peculiarly inefficient at feeding on small diatoms, even when they were available at very high concentrations. In this respect, the copepod differs from filterfeeding copepods, such as Calanus pacificus Brodsky. A possible explanation of this difference depends upon Aetideus being less capable of handling very small food particles than Calanus. Aetideus divergens and its congeners usually occur at subsurface depths not far below the mixed layer and seem to be adapted for feeding on large particles, possibly large phytoplanktonic organisms and fecal pellets, which sink out of the mixed layer.     

2000～2001年粤东柘林湾营养盐分布

2000年5月-2001年5月对粤东大规模增养殖区柘林湾及湾外附近海域进行了大量营养盐,浮游生物和一般理化因子的周年调查。结果表明,调查海域溶解性无机氮,磷,硅含量都明显偏高,年平均值分别达到22.64,1.95和59.7μmol/L,其中,氮,磷含量均超过国家三类海水的水质标准,由于湾顶黄冈河和湾周边排污排废的影响,营养盐的分布基本表现为由湾内向湾外,近岸向离岸递减的格局,大规模增养殖业造成的2次污染对该湾营养盐的时空分布具有重要的影响,柘林湾氮,磷,硅含量虽全面偏高,但如以Justic和Dortch等的标准来衡量,该湾浮游植物生长受控于单一营养盐限制因子的出现率为氮41.75%,磷22.9%,硅2.36%。     

Extraordinary prolongation of the life cycle in a freshwater planktonic copepod

The limnetic copepod Cyclops scutifer Sars shows an extraordinarily prolonged life cycle in a temperate lake near Oslo, Norway. Developmental sequences become one, two, and three years old, and there are circumstantial evidence of a four year old fraction. Prolongation of the cycle is mainly caused by two consecutive periods of diapause, the first as small copepodids during the second winter, the other as large copepodids during the third winter. There is a marked concentration of diapausing individuals in a small area of the bottom at the deepest part of the lake. There is evidence that this concentration is caused by a horizontal migration to areas with optimal oxygen conditions. The adaptive value of a prolongation of the life cycle is assumed to be an increase in the reproductive potential caused by a spreading out of the reproductive period by three year classes succeeding each other throughout the summer.     

Photoreactivation of UV-induced damage to embryos of a planktonic copepod

UV irradiation damaged the embryos of the planktonic copepodCalanus sinicus. The hatching rate was reduced, and the hatchedlarvae were deformed by the UV irradiation at unweighted intensitiessimilar to those occurring naturally. However, the UV-induceddamage was reduced by simultaneous irradiation with the visiblelight from a fluorescent lamp. This photoreactivation may playan important role in reducing the mortality of this speciesin the marine environment.