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1.
东海浮游桡足类的摄食活动及其对垂直碳通量的贡献 总被引：19，自引：7，他引：19
于１９９３年１０月和１９９４年４月在东海进行了桡足类自然群体肠道色素含量测定１９９４年４月还在２个４８ｈ连续观测站上进行肠道色素排空率实验。 相似文献
2.
珠江口浮游桡足类摄食研究 总被引：3，自引：0，他引：3
根据珠江口2002年7月(夏季)、2003年1月(冬季)和2003年4月(春季)3个航次浮游桡足类现场调查及其肠道色素实验数据,分析了浮游桡足类食性特点、肠道色素含量及其对浮游植物和初级生产力的摄食压力。根据齿缘指数对珠江口浮游桡足类食性分析,发现捕食性桡足类种数高于草食和杂食的滤食性种数,而其丰度低于后两者。珠江口桡足类个体肠道色素平均含量为冬季高于春季和夏季,而对浮游植物现存量和表层初级生产力的摄食压力均为夏季高于春季和冬季。夏、冬季桡足类肠道色素含量与水体叶绿素a浓度呈正相关,春季不相关。 相似文献
3.
2005年11月16日和27日,运用稀释法和桡足类添加法,对厦门宝珠屿海域小型浮游动物及桡足类的摄食对浮游植物生长的影响进行了研究.结果表明,各粒级浮游植物的生长率均大于小型浮游动物的摄食率,小型浮游动物对总的Chla和nano-Chla具有一致的显著的摄食作用(0.51～0.78d-1),当存在螺旋环沟藻等大型的异养甲藻时,亦能摄食micro-级浮游植物.所添加的桡足类主要摄食micro-级的浮游植物,也显著摄食小型浮游动物,16日,所添加的桡足类促进nano-级浮游植物的每天生长效应达0.03ind/dm3.说明了厦门海域小型浮游动物及桡足类的摄食共同控制着浮游植物的生长,由于桡足类的杂食性,可产生一定的营养级联效应. 相似文献
4.
小型桡足类在海洋生态系统中的功能作用 总被引：32，自引：10，他引：32
依据渤海周年的中型浮游动物网样品 ,研究了小型桡足类的优势种小拟哲水蚤(Paracalanusparvus)、强额拟哲水蚤 (Paracalanuscrassirostris)和双刺纺锤水蚤 (Acartiabifilosa)生物量的季节变动、分布和年产量 ,并与渤海大型桡足类的优势种中华哲水蚤 (Calanussinicus)进行了比较。结果表明 ,三种小型桡足类成体的年产量分别为 2 4 .89、1 0 .83和 1 9.5 4mgC/(m3·a) ,中华哲水蚤的年产量为 1 8.30mgC/(m3·a)。小型桡足类主要分布在近岸 ,特别是渤海湾和莱州湾 ,这里正好是许多经济鱼类的产卵场和育幼场 ;而中华哲水蚤主要分布在中央水域。小型桡足类的高峰季节持续时间长 ,从 4月到 1 0月 ,覆盖了几乎所有仔稚鱼大量出现的月份 ;而中华哲水蚤高峰季节持续时间短 ,仅 6月和 7月。另外 ,在粒度上 ,小型桡足类的卵、无节幼体、桡足幼体和成体都比中华哲水蚤等大型桡足类小了一个数量级 (按体积计 ) ,特别适合作为仔稚鱼的饵料。因此认为 ,在近海生态系统中 ,小型桡足类较之大型桡足类起更为重要的作用 相似文献
5.
海洋浮游桡足类摄食纤毛虫的研究 总被引：1，自引：0，他引：1
20世纪60年代起,人们发现了许多有关桡足类摄食纤毛虫的直接或间接的证据。20世纪70年代,有人在实验室内培养纤毛虫并开展桡足类对其清滤率的研究,结果表明桡足类对纤毛虫的清滤率为0.1—58.1mL/(ind.·h)。桡足类对纤毛虫的摄食方式有多种,包括伏击摄食和通过游泳过滤海水中的纤毛虫等。有的纤毛虫有逃避摄食的行为。20世纪80年代末,自然状况下桡足类群体对自然饵料中纤毛虫的摄食得到了研究,结果表明桡足类对纤毛虫的清滤率多数情况下低于40mL/(ind.·h)。实验室内和自然海区的研究都表明,与浮游植物相比,桡足类倾向于选择摄食纤毛虫。根据现场测定的清滤率和桡足类丰度估计自然海区桡足类对纤毛虫的摄食压力的大部分研究结果表明,桡足类群体对纤毛虫生物量的摄食压力大约为每天5%。这些自然海区的研究多集中在近岸区域,需要加强对大洋浮游桡足类摄食纤毛虫的研究。 相似文献
6.
白洋淀桡足类种类组成的调查 总被引：1，自引：0，他引：1
１９９５年３月－７月，我们对白洋淀的桡足类进行了调查，共发现桡足类１６种，隶属２亚科６属，同时对桡足类的区系进行了初步分析，并与沈嘉瑞，宋大祥１９６５年的调查做了比较，结果表明；两次调查的区系组成非常相近的，但种类差异较大。 相似文献
7.
桡足类是海洋生态系统中初级生产者和较高营养级消费者之间的关键联系环节,掌握桡足类的现场食物组成对于准确评估海洋食物网中的营养关系和能量转移至关重要。本研究中,我们以中华哲水蚤这一在中国、日本以及韩国近海具有重要生态地位的大型哲水蚤属桡足类为研究对象,应用之前开发的基于PCR的克隆技术,通过分析中华哲水蚤所摄食生物的18S rDNA序列,研究了中华哲水蚤的现场食物组成。结果揭示了南黄海（Y19站位）和渤海（B49站位）中华哲水蚤食物组成的多样性。共检测出43个操作分类单元（OTUs）,分别隶属于13个类群：硅藻（Bacillariophyta）、甲藻（Dinoflagellata）、硅鞭藻（Dictyochophyceae）、金藻（Chrysophyta）、Katablepharidophyta、浮生藻（Pelagophyceae）、无根虫（Apusozoa）、水螅水母（Hydrozoa）、栉水母（Ctenophora）、棘皮动物（Echinodermata）、被囊动物（Tunicata）、毛颚动物（Chaetognatha）以及海洋真菌。结果还表明,当发生藻类暴发时,中华哲水蚤可以摄食引发藻类暴发的藻种。当周围海域浮游植物的丰度相对较低时,中华哲水蚤可以选择摄食各种后生动物尤其是水螅水母和栉水母的卵、幼虫或者有机碎屑。我们的研究结果表明中华哲水蚤是一种杂食性桡足类,它对食物的选择依赖其生活海域中食物的可获得性。 相似文献
8.
利用现场海水培养实验,结合浮游动物网样数据,研究长江口邻近海域几种优势桡足类(中华哲水蚤、背针胸刺水蚤、太平洋纺锤水蚤和精致真刺水蚤)对微型浮游动物的摄食影响。结果表明,精致真刺水蚤虽然属于肉食性种类,但几乎不摄食微型浮游动物;其余三种杂食性桡足类中华哲水蚤、背针胸刺水蚤和太平洋纺锤水蚤对微型浮游动物(纤毛虫+异养甲藻)的摄食率分别为0.66、0.09和0.59μg C/(ind·d),分别占其日总摄食量的29%、24%和37%。其中,异养甲藻在初始生物量和对桡足类饵料贡献上分别占整个微型浮游动物的30%和28%,是微型浮游动物中一个重要的组成类群。中华哲水蚤对微型浮游动物的摄食率与初始食物浓度有显著的正相关关系,并且对体长20μm纤毛虫的清滤率要明显高于对体长20μm的纤毛虫(P0.01)的清滤率,表明其偏好摄食较大个体的食物。通过Chesson选择性指数显示,尽管微型浮游动物在生物量上远小于浮游植物,但桡足类能优先选择摄食微型浮游动物;进一步结合网采浮游动物数据,获得各站三种优势桡足类丰度平均占桡足类总丰度的77%,但它们对微型浮游动物现存生物量的摄食压力仅为0.8%,表明桡足类对微型浮游动物群落的下行控制作用并不明显,仍有大部分微型浮游动物生物量未通过摄食途径进入到桡足类群落中。 相似文献
9.
西湖硅藻对桡足类浮游动物繁殖的影响 总被引：7，自引：0，他引：7
本文报道从杭州西湖筛选分离的两种淡水硅藻，即尖针杆藻Ｓｙｎｅｄｒａａｃｕｓ和谷皮菱形藻Ｎｉｔｚｓｃｈｉａｐａｌｅａ对西湖两种淡水浮游桡足类，即近亲拟剑水蚤Ｐａｒａｃｙｃｌｏｐｓａｆｆｉｎｉｓ和大尾真剑水蚤Ｅｕｃｙｃｌｏｐｓｍｕｃｒｒｏｉｄｅｓ卵孵化率的影响。结果表明，在较高密度的硅藻培养液（１．２×１０４～５．４×１０４个／ｃｍ３）中培养的桡足类动物，其卵的孵化率比生活在自然水体中的有明显降低，并发现该密度的实验硅藻对其摄食者——桡足类的母体也产生一定的毒害作用。该实验结果与已报道的某些海洋硅藻对海洋桡足类存在毒害作用的结果，对水域生态系食物链（网）中硅藻作用的传统概念提出了挑战，对水域生态学研究提出了新课题。 相似文献
10.
三亚湾秋季桡足类分布与种类组成及对浮游植物现存量的摄食压力 总被引：6，自引：0，他引：6
秋季(11月底),桡足类针刺拟哲水蚤(Paracalanusaculeatus)和拟哲水蚤(Paracalanus)幼体为三亚湾优势种;强额孔雀哲水蚤(Pavocalanuscrassirostris)对浮游植物现存量的平均日摄食压力最大,各站平均为叶绿素a的(6.79±6.82)%,其次是针刺拟哲水蚤,平均为(5.97±5.67)%,亚强次真哲水蚤(Subeucalanussubcrassus)对浮游植物现存量的摄食压力较低,平均为(2.20±2.33)%,桡足类在秋季对浮游植物的日摄食压力占叶绿素a的(22.31±18.92)%。三亚湾属于生产力偏低的海区,对初级生产力的摄食压力以中型浮游动物针刺拟哲水蚤、锯缘拟哲水蚤(Paracalanusserrulus)、红纺锤水蚤(Acartiaerythraea)、微驼背隆哲水蚤(Acro calanusgracilis)和驼背隆哲水蚤(Acrocalanusgibber)为主,小型浮游动物的摄食压力也占一定的比例。 相似文献
11.
Copepod feeding in a coastal area of active tidal mixing: diel and monthly variations of grazing impacts on phytoplankton biomass 总被引：1，自引：0，他引：1
This study examined monthly feeding rates and grazing impact on phytoplankton biomass, as well as diel feeding rhythms of four key copepod species in a tidally well mixed estuary (Asan Bay, Korean Peninsula). Monthly ingestion rates estimated based on gut pigment analysis were closely associated with their peak densities, but not with phytoplankton biomass, implying high ingestion may be related to reproductive output for population growth. The three smaller copepods, Acartia hongi, Acartia pacifica and Paracalanus parvus, showed feeding preference for smaller phytoplankton (<20 μm) with higher clearance rates, whereas the larger Calanus sinicus preferred larger phytoplankton. Acartia pacifica and P. parvus showed distinct increased nocturnal feeding rates as measured with gut fluorescence, whereas A. hongi showed no significant day–night differences. Copepod diel feeding patterns were not associated with food quantity, and endogenous physiological rhythm might be hypothesized as responsible for the observed diel feeding patterns. Grazing impact on phytoplankton biomass by the four copepods in the estuary was on average 8% (range 0.2–29.8%) of the phytoplankton standing stock, similar to values reported in other coastal waters. Very high copepod abundances but low daily carbon ration (<20% for all copepods) provided by feeding on phytoplankton indicate that copepods also grazed on other non‐phytoplankton foods in Asan Bay. 相似文献
12.
Abstract. In situ feeding habits of the cyclopoid copepods Oncaea venusta, Corycaeus amazonicus, Oithona plumifera , and O. simplex were investigated by scanning electron microscope examination of fecal pellets, the contents of which reflected copepod gut contents upon capture. Peilet contents were compared with assemblages of phytoplankton present in surface waters at times of copepod collection. All samples were from the northern Gulf of Mexico. All four copepods fed upon phytoplankton and O. venusta also ingested other crustaceans. Dominant components of fecal pellets generally did not mirror those of available phytoplankton assemblages. In some cases, O. venusta ingested primarily larger-sized particles even when these were not most abundant, and in other cases it did not ingest large cells even when they were present in bloom concentrations. The presence of small (< 2–5 urn diameter) centric diatoms in O. venusta pellets suggests the possibility of feeding by mechanisms other than suspension or raptorial feeding. Limited observations suggest that C. amazonicus and O. plumifera may feed raptorially on larger particles even when these are not particularly abundant, and that the small O. simplex (< 500 nm total length) feeds mainly upon nanoplankton. It appears that cyclopoid feeding mechanisms are complex, and likely more so than those of many calanoids. 相似文献
13.
Community grazing rates of copepods were estimated from data taken during three cruises in Tokyo Bay, based on bottle incubations and a temporal variation of gut fluorescence. Special attention was paid to the feeding selectivity in the estimations. Differential grazing was observed in the copepod communities:Acartia omorii, abundant in February, selectively fed on the particles of dominant size classes, whileOithona davisae, dominant throughout the year, andCentropages abdominalis selected large particles (>20µm). The maximum filtering rates on certain size classes were several times the average. In addition, a 34-hr investigation of the gut fluorescence of copepods revealed nocturnal feeding inParacalanus spp.,Pseudodiaptomus marinus andOithona davisae.Copepod communities collected with a net (95-µm mesh opening) were estimated to graze, in February 3.0%, in August 3.1–4.5% and in November 4.2–11.9% of the standing crops of phytoplankton or suspended particles per day. 相似文献
14.
Juanita Urban-Rich Michael Dagg Jay Peterson 《Deep Sea Research Part II: Topical Studies in Oceanography》2001,48(19-20)
Mesozooplankton abundance, community structure and copepod grazing on phytoplankton were examined during the austral spring 1997 and summer 1998 as part of the US JGOFS project in the Pacific sector of the Antarctic polar front. Mesozooplankton abundance and biomass were highest at the polar front and south of the front. Biomass increased by 1.5–2-times during the course of the study. Calanoides acutus, Calanus propinquus, C. simillimus, Rhincalanus gigas and Neocalanus tonsus were the dominant large copepods found in the study. Oithona spp and pteropods were numerically important components of the zooplankton community. The copepod and juvenile krill community consumed 1–7% of the daily chlorophyll standing stock, equivalent to 3–21% of the daily phytoplankton production. There was an increased grazing pressure at night due to both increased gut pigment concentrations as well as increases in zooplankton numbers. Phytoplankton carbon contributed a significant fraction (>50%) of the dietary carbon for the copepods during spring and summer. The relative importance of phytoplankton carbon to the diet increased south of the polar front, suggested that grazing by copepods could be important to organic carbon and biogenic silica flux south of the polar front. 相似文献
15.
To improve our understanding of the trophic link between micro-zooplankton and copepods in Gyeonggi Bay, Yellow Sea, the diet composition, ingestion rates, and prey selectivity of Acartia hongi, known as the most abundant and widespread copepod species, was estimated by conducting in situ bottle incubation throughout the different seasons. The results showed that A. hongi preferentially grazed on ciliate and heterotrophic dinoflagellate of a size ranging from 20 to 100 μm rather than phytoplankton. Although micro-zooplankton comprised only an average 13.7% of the total carbon available in the natural prey pool, micro-zooplankton accounted for >70% of the total carbon ration ingested by A. hongi throughout the year, except for winter diatom blooming periods when A. hongi obtained about 60% of its carbon ration from phytoplankton. Our results demonstrated that A. hongi modified their diet composition and feeding rates in response to change in composition and size of prey available to them, and that A. hongi preferentially ingested micro-zooplankton over phytoplankton. Feeding activity of A. hongi could therefore affect the species composition and size structure of natural plankton communities in this study area, particularly the micro-zooplankton. Strongly selective feeding and high grazing pressure by A. hongi on micro-zooplankton shows the role of trophic coupling between copepods and the microbial food web in the pelagic ecosystem of Gyeonggi Bay. 相似文献
16.
Andrew W. Leising James J. Pierson Claudia Halsband-Lenk Rita Horner James Postel 《Progress in Oceanography》2005,67(3-4):384
During late winter and spring of 2002 and 2003, 24, 2–3 day cruises were conducted to Dabob Bay, Washington State, USA, to examine the grazing, egg production, and hatching success rates of adult female Calanus pacificus and Pseudocalanus newmani. The results of the copepod grazing experiments for C. pacificus are discussed here. Each week, copepod grazing incubation experiments from two different depth layers were conducted. Grazing was measured by both changes in chlorophyll concentration and cell counts. In 2002, there was one moderate bloom consisting mainly of Thalassiosira spp. in early February, and a larger bloom in April comprised of two Chaetoceros species and Phaeocystis sp. Similarly, in 2003, there were two blooms, an early one dominated by Thalassiosira spp., and a later one consisting of Chaetoceros spp. and Thalassiosira spp. Clearance rates on individual prey species, as calculated by cell counts, showed that C. pacificus are highly selective in their feeding, and may have much higher clearance rates on individual taxa than rates calculated from bulk chlorophyll disappearance. During weeks of high phytoplankton concentration, the copepods generally ate phytoplankton. However, they often rejected the most abundant phytoplankton species, particularly certain Thalassiosira spp., even though the rejected prey were often of the same genus and similar size to the preferred prey. It is speculated that this avoidance may be related to the possible deleterious effects that certain of these diatom species have on the reproductive success of these copepods. During weeks of medium to low phytoplankton concentration, the copepods selectively ate certain species of phytoplankton, and often had high electivity for microzooplankton. The selection mechanism must consist of active particle rejection most likely based on detection of surface chemical properties, since the diatoms that were selected were of the same genus, nearly the same size, and at lower numerical abundance than those cells that were avoided. The grazing choices made by these copepods may have important consequences for the overall ecosystem function within coastal and estuarine systems through changes in the transfer efficiency of energy to higher trophic levels. 相似文献
17.
Abstract. The patterns and rates of feeding by the copepod Acartia hudsonica and larvae of the polychaete Polydora sp. were investigated during the spring in an estuarine embayment. These dominant macrozooplankters fed upon the natural particulate assemblages (predominantly dino-flagellates) spiked with the toxic dinoflagellate Gonyaulax tamarensis. G. tamarensis was ingested by both zooplankters, as was Heterocapsa triquetra , the most abundant alternative food item. Ingestion rates generally increased as dinoflagellate concentrations increased, resulting in a relatively constant (and low) filtration rate for each grazer. Dinophysis acuminata , another dominant dinoflagellate, was essentially ungrazed. Thus, the zooplankters did not ingest one dinoflagellate and consumed others in proportion to their availability but at low rates. Based on these low rates and the small number of A. hudsonica observed during the spring, we infer minima! grazing impact on a 1980 G. tamarensis bloom. In contrast, the impact of polychaete larvae may have been substantial, since their extreme numerical abundance more than compensated for low filtration rates.
In one instance, the tintinnid Eutintinnus pectinis was accidentally included in a grazing experiment. Our ingestion data demonstrate that A. hudsonica , when presented with a combination of tintinnids and several species of phytoplankton (G. tamarensis and D. acuminata) ingested the tintinnids at high rates, in proportion to their high abundance. Since the nanoflagellate Chroomonas amphioxea was found within the loricae of many of the surviving tintinnids, this also provided a qualitative demonstration of the often-hypothesized nanoplankton to tintinnid to copepod link in a marine food chain. 相似文献
In one instance, the tintinnid Eutintinnus pectinis was accidentally included in a grazing experiment. Our ingestion data demonstrate that A. hudsonica , when presented with a combination of tintinnids and several species of phytoplankton (G. tamarensis and D. acuminata) ingested the tintinnids at high rates, in proportion to their high abundance. Since the nanoflagellate Chroomonas amphioxea was found within the loricae of many of the surviving tintinnids, this also provided a qualitative demonstration of the often-hypothesized nanoplankton to tintinnid to copepod link in a marine food chain. 相似文献
18.
Preliminary study of the retention mechanism of planktonic copepods in the Jiulong Estuary in China 总被引：1，自引：0，他引：1
The horizontal and vertical distribution patterns of five planktonic copepods,Calanus sinicus, Acartia pacifica, Tortanus derjugini, Acartiella sinensis and Pseudodiaptomus poplesia, predominant in the Jiulong Estuary, were investigated from May 2003 to April 2004. The results showed that the distribution of these copepods was related to the tidal period but that each species had its own specific pattern. C. sinicus showed no tidal vertical migration behavior and was thought to be a non-resident species in this estuary. Among Acartia pacifica,T. derjugini,Acartiella sinensis, more individuals occurred in the surface than in the bottom waters during flood tide, and the pattern was reversed during ebb tide. The epibenthic copepod P. poplesia usually remained in the bottom waters in the upstream part of the estuary, but it displayed strong tidally-oriented vertical migration in the middle reaches of the estuary.Taking into account the hydrographic characteristics of the Jiulong Estuary,it was hypothesized that the planktonic copepods in this estuary had more or less adopted the mechanism of vertically migrating to the surface waters during flood tide in order to make use of the inflowing tide, and then sinking to the bottom during ebb tide to avoid being carried out of the estuary by net outflow. 相似文献
19.
福建深沪湾浮游桡足类的分布 总被引：1，自引：0，他引：1
根据1998年5、9月福建省深沪湾环境综合调查所采的浮游生物样品，对该湾桡足类的种类组成及其与环境因子的关系进行了分析研究。结果表明：桡足类已鉴定到种的有28种，划分为4个生态类群，以沿岸类群为主。其优势种为驼背隆哲水蚤（Acrocalanus gibber)、太平洋纺锤水蚤（Acartia pacifica)、瘦尾胸刺水蚤（Centropages tenuiremis) 和近缘大眼剑水蚤（Corycaeus affinis)等。5月份的桡足类个体数比9月份的高，其数量与浮游植物细胞数呈正相关（除S4站外）关系。湾顶和梅林附近海域基础饵料丰富，是鱼类索饵的良好场所。 相似文献
20.
Andrew W. Leising James J. Pierson Claudia Halsband-Lenk Rita Horner James Postel 《Progress in Oceanography》2005,67(3-4):406
During late winter and spring of 2002 and 2003, 24 two- to three-day cruises were conducted to Dabob Bay, Washington State, USA, to examine the grazing, egg production, and hatching success rates of adult female Calanus pacificus and Pseudocalanus newmani. Here, we discuss the results of our grazing experiments for P. newmani. Each week, we conducted traditional microzooplankton dilution experiments and “copepod dilution” experiments, each from two different layers. Grazing was measured by changes in chlorophyll concentration and direct cell counts. Clearance rates on individual prey species, as calculated by cell counts, showed that Pseudocalanus are highly selective in their feeding, and may have much higher grazing rates on individual taxa than calculated from bulk chlorophyll disappearance. The grazing rates of the copepods, however, are typically an order of magnitude lower than the grazing rates of the microzooplankton community, or the growth rates of the phytoplankton. P. newmani ingested diatoms, but, at certain times fed preferentially on microzooplankton, such as ciliates, tintinnids, and larger dinoflagellates. Removal of the microzooplankton may have released the other phytoplankton species from grazing pressure, allowing those species’ abundance to increase, which was measured as an apparent “negative” grazing on those phytoplankton species. The net result of grazing on some phytoplankton species, while simultaneously releasing others from grazing pressure resulted in bulk chlorophyll-derived estimates of grazing which were essentially zero or slightly negative; thus bulk chlorophyll disappearance is a poor indicator of copepod grazing. Whether copepods can significantly release phytoplankton from the grazing pressure by microzooplankton in situ, thus causing a trophic cascade, remains to be verified, but is suggested by our study. 相似文献