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1.
兴化湾浮游动物群落季节变化和水平分布   总被引:4,自引:0,他引:4  
兴化湾为福建北部最大的海湾,于2006年对该海湾浮游动物群落进行了四季9个站位的调查。共检出浮游动物及幼虫124种,其中春季42种,夏季89种,秋季71种,冬季20种;分属近岸暖温、近岸暖水和广布外海3个生态类群;优势种15种,春季以水母和桡足类占优势,夏季以水母占优势,秋季以水母、桡足类和箭虫占优势,冬季则以桡足类占优势。不同季节兴化湾浮游动物生物量湿重和丰度水平分布特征变化明显,并与温度和盐度呈显著相关。聚类分析显示兴化湾浮游动物群落夏季类群和秋季类群相似度较高;各季节水平分布基本可分为湾口区和湾内区两大类群。与20世纪80年代相比,尽管本次调查浮游动物群落没有表现出显著差异,但随着电厂等大规模工程的投产,兴化湾海域生态系统健康面临着极大威胁,其环境压力需引起持续关注。  相似文献   

2.
Masero  R.  Villate  F. 《Hydrobiologia》2004,518(1-3):201-212
Hydrobiologia - The effects of natural and anthropogenic factors on the vertical distribution of zooplankton benthic eggs of the sediments were analysed in the estuaries of Bilbao and Mundaka, both...  相似文献   

3.
4.
《农业工程》2014,34(3):141-147
Qinzhou Bay, the biggest bay in Guangxi Province, is very species-rich and is developing a robust marine economy. In recent years, as human impact has increased, problems associated with the environment have become more complicated. Measuring zooplankton diversity and abundance is a way to monitor environmental conditions. According to the data from four ecological surveys of the zooplankton in Qinzhou Bay during 2008 and 2009, a total of 134 species of zooplankton were identified, including 52 Copepoda species, 27 Medusa species, 14 Planktonic larvae, 9 Chaetognatha species, 8 Pteropoda species, 5 Amphipoda species, 4 Cladocera species, 4 Ostracoda species, 3 Thaliacea species, 2 Appendiculata species, 2 Sergestdae species, 2 Protlsta species, 1 Rotiera species and 1 Cumacea species. The fauna was clearly characterized as tropical population. The total species number was highest in autumn, followed by spring, winter and summer. Zooplankton species diversity in Qinzhou Bay has increased compared with the results obtained in 1983–1985 (83 species). However, compared with other bays, the number of zooplankton species in Qinzhou Bay is close to Daya Bay (128), higher than in Zhilin Bay (60), Jiaozhou Bay (81) and Luoyuan Bay (70), and far lower than in the north South Sea (709). We adopted the dominant index Y > 0.02 as the distinguishing standard of dominant species. The number of dominant species in spring, summer, autumn and winter were six, nine, eight and five. There was only one common dominant species (Penilia avirostris) appeared in different seasons, For summer and autumn, the shared dominant species numbered about four. Between other seasons, the shared dominant species varied between two and three. The number of uniquely dominant species was four in summer, three in autumn and one in both spring and winter. The dominant species in different seasons have some overlaps and some differences. The average biomass of zooplankton was 378 mg/m3 at all times of year. The average biomass was largest in autumn, followed by winter, and was the least in spring and summer. The average density of zooplankton for the entire year was 805.11 ind/m3. The average density was largest in summer, followed by winter, and was least in autumn and spring. Copepoda and Planktonic larvae were the major components of zooplankton in spring and summer at Qinzhou Bay, with the other species’ densities under 10%. In autumn, Copepoda, Planktonic larvae and Chaetognatha were the major components of the biomass, and in winter, the major species were Copepoda and Cladocera, with the others species’ density under 10%. The average value of the Shannon–Wiener diversity index (H′) was 3.84 and the evenness index (J′) was 0.77. The zooplankton diversity index and community evenness overall were good and the community organization had a complete and stable state, but the status of the community was relatively weak. The relationship between biomass/density of zooplankton and environmental factors is remarkable. Biomass and density are positively correlated with temperature and nutrient concentration, and are negatively correlated with salinity.  相似文献   

5.
Summary Vertical distributions of various species and stages of zooplankton at different times of the day were determined by stratified sampling with the BIONESS in northeastern Baffin Bay during early August. The water column was divided into an upper subarctic zone (>0° C, salinity < 32), a lower subarctic zone (< 0° C, salinity 32 to 34) and a deep zone of Atlantic water (>0° C, salinity 34). The upper subarctic zone was dominated by two species of pteropod molluscs; the lower subarctic water was dominated by the copepods, Calanus finmarchicus, C. glacialis and C. hyperboreus whose copepodite stages showed depth distributions that were different from one another, with the copepodite stage 5 and adult females generally shallower than the younger stages. All stages of all Calanus species were in the zone of primary production (10 to 50 m) while the copepods Pseudocalanus, Metridia and Oithona were generally found below this zone. Only C. finmarchicus and C. glacialis showed evidence of diurnal migration, migrating to the surface waters when the sun was at its lowest position on the horizon (i.e. at 0100 h).  相似文献   

6.
为了解西北太平洋亚热带海域浮游动物群落结构,根据2019年3月"淞航号"调查船在西北太平洋(28°--35° N,147°--154° E)44个站点进行渔业资源调查期间采集的浮游动物样本,分析了浮游动物的种类组成与分布.结果 表明:该海域共鉴定出浮游动物456种(含浮游幼体和未定种),属于14个类群8个门类,其中桡足...  相似文献   

7.
大亚湾海域浮游动物生态特征   总被引:2,自引:0,他引:2  
方良  李纯厚  杜飞雁  贾晓平  张伟 《生态学报》2010,30(11):2981-2991
2004年3月(春季)、5月(夏季)、9月(秋季)和12月(冬季)4个航次对大亚湾海域浮游动物进行了调查。共计鉴定浮游动物128个种类,浮游幼体14个类群。浮游动物出现的种类数依次是:夏季(90种),秋季(81种),冬季(71种),春季(47种)。浮游动物的丰度以夏季最高,平均1013.38 ind.m-3;其次是秋季,平均913.30 ind.m-3;春季最低,平均162.37 ind.m-3。浮游动物生物量的季节变化:秋季(773.89 mg.m-3),夏季(472.82 mg.m-3),冬季(286.44 mg.m-3),春季(164.11 mg.m-3),生物量高低与种类组成关系密切,秋季优势类群为水母类和毛颚类等大型浮游动物,所以生物量较高。4个季节的Shannon-Wiener多样性指数H′值、物种均匀度指数J值和物种丰富度指数D值的变化趋势十分相似:春季的3项指数值均最低,冬季最高,夏、秋季节相差不大。此外,分析结果表明:毛颚类作为优势种且4个季节均有出现,是对大亚湾海域水体较20a前水温上升的响应;浮游动物近岸生物量高于湾中部;从丰度的平面分布看,大亚湾海域浮游动物栖息环境已经不同程度受到大型建设工程和人类活动的影响。  相似文献   

8.
A principal component and discriminant function analysis of zooplankton from the Sanyati Bay, Lake Kariba, indicated that the distribution of plankton was associated with the riverine in-flow into the lake.  相似文献   

9.
The vertical distribution of meiobenthic copepods was investigated within muddy sediments of a eutrophic lagoon (fish ponds of Arcachon Bay, France). The aim of the study was to determine if in muddy sediments, as previously established in sandy sediments, meiobenthic copepods migrate vertically according to the seasons or diel periods. Two experimental approaches were used, viz: a three-season comparison was made of the diel vertical distribution of the harpacticoid Canuella perplexa T. & A. Scott (1893) and secondly the depth distribution of a meiobenthic copepod assemblage was followed for a 24 h period, in shallow water subtidal locations. The harpacticoid C. perplexa vertically migrated through the top three centimeters of the sediment, showing diel and seasonal variations in depth distribution. The differential vertical distributions shown by the dominant meiobenthic populations suggest that emergence into the water column may mainly concern surface dwelling copepods. The physical and biological factors affecting seasonal and diel changes in the copepod assemblage of the fish ponds are discussed.  相似文献   

10.
Zooplankton composition and distribution were investigated on the Laptev Sea shelf, over the continental slope and in the adjacent deep Nansen Basin during the joint German-Russian expedition “Arctic 93” with RV Polarstern and Ivan Kireyev in August/September 1993. In the shelf area biomass decreased from west to east with the lowest values in the area influenced by the Lena river runoff. A gradual increase of biomass from the shallow to the deep area correlated with water depth. Total biomass ranged between 0.1 and 1.5 g m−2 on the shelf and 4.7 and 7.9 g m−2 in the adjacent Nansen Basin. On the shelf Calanus glacialis/finmarchicus dominated overall. The contribution of brackish-water taxa was low in the west, where high salinity and southward currents from the Arctic Basin supported a marine neritic community, but on the southern and eastern Laptev shelf, in the areas of freshwater influence, brackish-water taxa contributed up to 27% of the total biomass. On the slope and in deep areas a few large Arctic copepod species, Calanus glacialis, C. hyperboreus and Metridia longa, composed the bulk of biomass and determined the pattern of its vertical distribution. The export of Calanus species from the Nansen Basin onto the Laptev shelf appears to be of great importance for the shelf communities. In turn, the eastern outer shelf and slope area of the Laptev Sea are thought to have a pronounced effect on the deep basin, modifying the populations entering the central Arctic. Received: 25 March 1997 / Accepted: 18 July 1997  相似文献   

11.
Daya Bay was undergoing eutrophication process by increased nutrient loading, and the changes in nutrients have strongly influenced the phytoplankton community structure. Ciliates are common component of planktonic community, what role do ciliates play in Daya Bay was still unknown. In this study, ciliates were enumerated and identified from the inner and outer Daya Bay during three seasons. Thirty-one species belong to 16 genera of ciliates were recorded, and Cyclotrichida, Strombidiida, Tintinnida were most common. In spring, ciliates abundance of D2 was lower than D1 and D3, abundance in the surface of D1 and D3 were higher than in the bottom, while D2 showed the opposite character. The lowest ciliate abundance was found in the E1 in summer. In fall, Ciliates abundance of D3 was lower than in fall, and abundance in the surface was lower than in the bottom, which was different compared to in spring. Different hydrographic character was shown between the surface (high temperature, low salinity and nutrients) and bottom layer (low temperature, high salinity and nutrients) at E1 in summer. Ciliate abundance had no significant variation between the surface and bottom at E1 in summer, but ciliates community structure changed a lot.  相似文献   

12.
Daya Bay was undergoing eutrophication process by increased nutrient loading, and the changes in nutrients have strongly influenced the phytoplankton community structure. Ciliates are common component of planktonic community, what role do ciliates play in Daya Bay was still unknown. In this study, ciliates were enumerated and identified from the inner and outer Daya Bay during three seasons. Thirty-one species belong to 16 genera of ciliates were recorded, and Cyclotrichida, Strombidiida, Tintinnida were most common. In spring, ciliates abundance of D2 was lower than D1 and D3, abundance in the surface of D1 and D3 were higher than in the bottom, while D2 showed the opposite character. The lowest ciliate abundance was found in the E1 in summer. In fall, Ciliates abundance of D3 was lower than in fall, and abundance in the surface was lower than in the bottom, which was different compared to in spring. Different hydrographic character was shown between the surface (high temperature, low salinity and nutrients) and bottom layer (low temperature, high salinity and nutrients) at E1 in summer. Ciliate abundance had no significant variation between the surface and bottom at E1 in summer, but ciliates community structure changed a lot.  相似文献   

13.
Summary 1. During summer 1970, plankton samples were taken in the Bay of Eilat (Red Sea) to study vertical distributions and diurnal migrations of zooplankton. In June, a collecting programme was conducted over 24 hours. Samples were taken with a closing net every 2 hours, at dawn and dusk every hour. The following depth ranges were sampled: 300 to 200 m, 200 to 150 m, 150 to 100 m, 100 to 75 m, 75 to 50 m, 50 to 25 m, and 25 m to water surface.2. The plankton concentration (accumulated displacement volume of all samples from a certain depth) decreases slowly from the surface to 100 m, then rapidly to 300 m depth. Maximum concentrations are found between 25 and 50 m.3. In Copepoda, Gastropoda and Chaetognatha, the concentration of individuals decreases with increasing depth. Gastropoda and Chaetognatha may exhibit reductions of 50% over a single 25-m step. The Appendicularia concentration is high between 25 and 50 m; it decreases towards the surface and with increasing depth.4. As far as it is possible to ascertain the diurnal vertical migrations of these animal groups without separation into species, the four groups can be said to avoid the upper layers during daytime; during this time they occur below 50 m. Around sunset and sunrise, gastropods, chaetognaths and appendicularians tend to accumulate above 25 m.
Die vertikale Verteilung und tägliche Wanderung einiger Zooplankter in der Bucht von Eilat (Rotes Meer)
Kurzfassung Im Sommer 1970 wurden zum Studium der vertikalen Verteilung und täglichen Vertikalwanderung des Zooplanktons in der Bucht von Eilat (Rotes Meer) Planktonfänge durchgeführt. Während eines Sammelprogramms von 24 Studen im Juni wurden Schließnetzfänge alle zwei Stunden und während des Sonnenauf- und -unterganges jede Stunde aus folgenden Tiefenbereichen entnommen: 300–200 m, 200–150 m, 150–100 m, 100 bis 75 m, 75–50 m, 50–25 m und 25 m bis zur Wasseroberfläche. Die Dichte des Planktons (das displacement volume aller Fänge einer bestimmten Tiefenschicht wurde addiert) nimmt bis in die Tiefe von 100 m langsam, danach schnell ab. Die größte Dichte liegt zwischen 25 und 50 m. Die Anzahl der Copepoden, Gastropoden und Chaetognathen je Planktonprobe nimmt mit zunehmender Meerestiefe ab, im Falle der Gastropoden und Chaetognathen sogar von 25-m-Stufe zu 25-m-Stufe um 50%. Die Appendicularien sind zwischen 25 und 50 m Tiefe am häufigsten; ihre Dichte nimmt nach oben und nach unten deutlich ab. Es wird versucht, die tägliche Vertikalwanderung zu beschreiben. Alle vier untersuchten Gruppen meiden das Tageslicht; sie halten sich am Tage vorzugsweise unterhalb 50 m auf. Bemerkenswert sind die hohen Dichten der Gastropoden, Chaetognathen und Appendicularien während des Sonnenaufgangs und -untergangs in den oberen Wasserschichten.
  相似文献   

14.
乐清湾浮游动物的季节变动及摄食率   总被引:11,自引:1,他引:11  
2002年8月、11月、2003年2月和5月,在乐清湾进行了4个航次生物、化学和水文等专业综合调查。根据采集的浮游动物样品的分析鉴定及海上现场实验结果,对浮游动物的群落组成、生物量、丰度、多样性指数的分布和季节变动及其浮游动物对浮游植物的摄食率进行研究。结果表明,乐清湾已鉴定的浮游动物有56属,75种,17类浮游幼体,主要可划分为4个生态类群,以近岸低盐类群为主,其优势种为真刺唇角水蚤Labidoceraeuchaeta、太平洋纺锤水蚤Acartiapacifica、驼背隆哲水蚤Acrocalanusgibber、中华假磷虾Pseudeuphausiasinica和百陶箭虫Sagittabedoti等,半咸水河口类群、暖水性外海种和广布种的种数相对较少。浮游动物生物量和丰度的平面分布趋势基本一致,有明显季节变化。2月份和5月份,浮游动物生物量和丰度,从湾顶向湾口呈逐渐增加趋势;8月份,生物量和丰度的分布与2月份、5月份的分布趋势不同,从湾顶向湾口,生物量和丰度逐渐降低;11月份,生物量和丰度的平面分布相对均匀。浮游动物种类多样性指数有明显的季节变化,其动态变化与浮游动物种数和丰度的变化一致。微型浮游动物对浮游植物存在摄食压力,且摄食率有季节变化,摄食率的变化在0.15~0.48d-1。  相似文献   

15.
The objective of this study was to investigate whether successiverecruitment failures in the anchovy fishery in the Bay of Biscaywere due to changes in the zooplankton biomass or composition.Image analysis and automatic recognition were used to analysezooplankton samples collected during diel egg production methodspring surveys from 1998 to 2006. We were not able to detectany trend in zooplankton biomass during this period. The zooplanktonspatial distribution showed permanent features with large organismsbeing more abundant over the shelf break and outer areas. Finally,we found a negative correlation between anchovy recruitmentand zooplankton biomass which suggests that the 2002–2006failures in anchovy recruitment in the Bay of Biscay are notdue to a decrease in mesozooplankton biomass.  相似文献   

16.
Quantitative zooplankton samples were obtained monthly or bi-monthly 15 times from June 1974 to May 1975 at three stations in lower Delaware Bay. Two 12-hour cruises were also conducted at one of the stations.Arthropods dominated the samples in terms of number of species and number of individuals. The number of zooplankton from surface samples ranged from 58/m3 in August to 21,092/ m3 in June, while bottom samples varied from 259/m3 in August to 30,395/ m3 in October. In general, larger concentrations of individuals were found in bottom samples.Only on three occasions did meroplankton exceed the holoplankton, and these occurred at the shallow water stations. Meroplankton comprised a larger percentage of the bottom samples than surface samples. Zoeae of Neopanope sayi and Uca sp. contributed mainly to the large proportion of meroplankton in July 1974, veligers of Mytilus edulis in January 1975, and nauplii of Balanus sp. in May 1975.Copepods were the largest component of the population throughout most of the year. At all stations and depths, Arctica tonsa dominated most of the summer samples. In the spring of 1975, A. tonsa was replaced by Centropages hamatus, Temora longicornis, and Pseudocalanus minutus.During the 12-hour cruises there were higher numbers of individuals in the bottom waters in the day with migration to surface waters in the afternoon and evening. Based on cluster analysis, five time-related assemblages were discerned: June, July–August, September–November, December, January–May. Comparison of Delaware Bay zooplankton with other estuarine systems indicated that the densities obtained locally were most similar to those reported in the York River, Virginia.  相似文献   

17.
三沙湾浮游动物生态类群演替特征   总被引:4,自引:0,他引:4  
徐佳奕  徐兆礼 《生态学报》2013,33(5):1413-1424
根据2010年6月-2011年5月三沙湾海域5个航次海洋综合调查资料,对三沙湾浮游动物种群特征进行分析,并与我国不同纬度海湾生态类群结构进行比较.探讨三沙湾海域浮游动物生态类群季节变化特征及其受水团季节变化的影响.研究结果表明:4月和5月三沙湾海域主要受到浙闽沿岸流影响,生物多样性H'指数分别为2.03和2.02;种类数分别仅为17种和19种,明显低于6月、8月和10月;浮游动物生态类群以暖温带近海种为主;优势种种类数少,单一优势种优势性明显,4月中华哲水蚤丰度占浮游动物总丰度的65.03%;群落结构特征与同期我国长江口浮游动物区系特征相似.6月三沙湾海域受到浙闽沿岸流和台湾暖流共同影响,同时因闽北雨季导致大量大陆径流汇入,使得该月浮游动物种群结构复杂,生物多样性指数和种类数全年最高,为3.12和45种,与5月相比,种类更替明显,物种更替率为69.39%;亚热带近海种丰度百分比最高(73.03%),亚热带外海种种类数百分比次之(48.89%),是海域浮游动物生态类群由以暖温带近海种为主向以亚热带外海种为主的过渡时期.8月和10月浙闽沿岸流消失,三沙湾海域受台湾暖流控制,海水温度和盐度升高,生物多样性指数和种类数均略低于6月;生态类群结构以亚热带外海种为主;优势种特征表现为种类数多而各个优势种丰度较低;浮游动物群落结构特征与南海北部海域浮游动物组成极为相似.  相似文献   

18.
Zooplankton was sampled during the summer of 1995 from a grid of 34 shelf stations located off the Ria de Aveiro (northwestern Portugal), which were arranged into cross-shore transects extending either to the shelf break or to the 50 m isobath. At each station, a bongo net was hauled obliquely from close to the bottom or a maximum depth of 50 m to the surface. STD casts were made also at each station and wind data were obtained from a land station. Analysis of salinity and temperature data detected the presence of strong thermohaline stratification and a lens of reduced salinity water at the surface. A well-defined front, located at a depth of 10 to 35 m, separated cold water close to shore from warmer offshore water. Isopycnals between the front and the shore were bent towards the surface. The structure of the thermohaline features was consistent with the upwelling-favourable winds measured during the sampling period. A classification and a multivariate analysis of variance of the more abundant species showed the presence of two distinct assemblages that were separated by the front, indicating that these formations are important features structuring the zooplanktonic community of upwelling areas. The data further indicate that the zooplankton was composed of Palaeartic Atlantic and Mediterranean neritic species, and that oceanic species were absent from the samples. The absence of oceanic species is interpreted as resulting from the offshore displacement of the slope poleward flow and of the Portugal Current that takes place during the summer, as a response to upwelling-favourable winds.  相似文献   

19.
The two estuarine systems composing San Francisco Bay have distinct zooplankton communities and seasonal population dynamics. In the South Bay, a shallow lagoon-type estuary, the copepods Acartia spp. and Oithona davisae dominate. As in estuaries along the northeast coast of the U.S., there is a seasonal succession involving the replacement of a cold-season Acartia species (A. clausi s.l.) by a warm-season species (A. californiensis), presumably resulting from the differential production and hatching of dormant eggs. Oithona davisae is most abundant during the fall. Copepods of northern San Francisco Bay, a partially-mixed estuary of the Sacramento-San Joaquin Rivers, organize into discrete populations according to salinity distribution: Sinocalanus doerrii (a recently introduced species) at the riverine boundary, Eurytemora affinis in the oligohaline mixing zone, Acartia spp. in polyhaline waters (18–30\%), and neritic species (e.g., Paracalanus parvus) at the seaward boundary. Sinocalanus doerrii and E. affinis are present year-round. Acartia clausi s.l. is present almost year-round in the northern reach, and A. californiensis occurs only briefly there in summer-fall. The difference in succession of Acartia species between the two regions of San Francisco Bay may reflect differences in the seasonal temperature cycle (the South Bay warms earlier), and the perennial transport of A. clausi s.l. into the northern reach from the seaward boundary by nontidal advection.Large numbers (>106 m–3) of net microzooplankton (>64 µm), in cluding the rotifer Synchaeta sp. and three species of tintinnid ciliates, occur in the South Bay and in the seaward northern reach where salinity exceeds about 5–10 Maximum densities of these microzooplankton are associated with high concentrations of chlorophyll. Meroplankton (of gastropods, bivalves, barnacles, and polychaetes) constitute a large fraction of zooplankton biomass in the South Bay during winter-spring and in the northern reach during summer-fall.Seasonal cycles of zooplankton abundance appear to be constant among years (1978–1981) and are similar in the deep (>10 m) channels and lateral shoals (<3 m). The seasonal zooplankton community dynamics are discussed in relation to: (1) river discharge which alters salinity distribution and residence time of plankton; (2) temperature which induces production and hatching of dormant copepod eggs; (3) coastal hydrography which brings neritic copepods of different zoogeographic affinities into the bay; and (4) seasonal cycles of phytoplankton.  相似文献   

20.
Grazing of dominant zooplankton copepods (Calanoides acutus, and Metridia gerlachei), salps (Salpa thompsoni) and microzooplankton was determined during the austral summer of 1998/1999 at the seasonal ice zone of the Prydz Bay region. The objective was to measure the ingestion rates of zooplankton at the seasonal ice zone, so as to evaluate the importance of different groups of zooplankton in their grazing impact on phytoplankton standing stock and primary production. Grazing by copepods was low, and accounted for <1% of phytoplankton standing stocks and 3.8-12.5% of primary production for both species during this study; even the ingestion rates of individuals were at a high level compared with previous reports. S. thompsoni exhibited a relatively high grazing impact on primary production (72%) in the north of our investigation area. The highest grazing impact on phytoplankton was exerted by microzooplankton during this investigation, and accounted for 10-65% of the standing stock of phytoplankton and 34-100% of potential daily primary production. We concluded that microzooplankton was the dominant phytoplankton consumer in this study area. Salps also played an important role in control of phytoplankton where swarming occurred. The grazing of copepods had a relatively small effect on phytoplankton biomass development.  相似文献   

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