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1.
The invasive ctenophore Mnemiopsis leidyi (Agassiz), which was transported from the Black Sea into the Caspian Sea at the end of the 1990s, has negatively affected the ecosystem of the Caspian Sea. Zooplankton abundance, biomass and species composition were evaluated on the Iranian coast of the Caspian Sea during 2001–2006. A total of 18 merozooplankton (13 species composed of larvae of benthic animals) and holozooplankton (four Copepoda and one Cladocera) species were identified. The total number of zooplankton species found here was 50% less than in a previous investigation performed in the same region in 1996 before the introduction of Mnemiopsis leidyi into the Caspian Sea. Cladocera species seemed to be highly affected by the invasion of Mnemiopsis leidyi; only one species, Podon polyphemoides, remained in the study area, whereas 24 Cladocera species were found in the study carried out in 1996. Whereas among the Copepoda Eurytemora minor, Eurytemora grimmi, Calanipeda aquae dulcis and Acartia tonsa that were abundant before the Mnemiopsis leidyi invasion, only A. tonsa (copepodites and adults) dominated the inshore and offshore waters after the invasion. The maximum in zooplankton abundance (22,088 ± 24,840 ind·m?3) and biomass (64.1 ± 56.8 mg·m?3) were recorded in December 2001 and August 2004, respectively. The annual mean zooplankton abundance during 2001–2006 was in the range of 3361–8940 ind·m?3; this was two‐ to five‐fold less than the zooplankton abundance in 1996. During 2001–2006, the highest abundance and biomass of Mnemiopsis leidyi were observed during summer‐autumn months coincident with warm temperatures and generally when the abundance of other zooplankton organisms was low.  相似文献   

2.
Samples were collected with a plankton net in the four seasonal cruises during 2006-2007 to study the seasonal variability of the zooplankton community in the southwest part of Huanghai Sea Cold Water Mass (HSCWM, Yellow Sea Cold Water Mass). The spatial and temporal variations of zooplankton species composition, biomass, abundance and biodiversity were examined. A total of 122 zooplankton species and 30 pelagic larvae were identified in the four cruises. Calanus sinicus and Aidanosagitta crassa were the most dominant species, and Themisto gaudichaudi and Euphausia pacifica were widely distributed in the HSCWM area. The spatial patterns of non-gelatinous zooplankton (removing the high water content groups) were similar to those of the total zooplankton biomass in autumn, but different significantly in the other three seasons. The seasonal means of zooplankton biomass in spring and summer were much higher than that in autumn and winter. The total zooplankton abundance averaged 283.5 ind./m~3 in spring (highest), 192.5 ind./m~3 in summer, 165.5 ind./m~3 in autumn and 65.9 ind./m~3 in winter (lowest), and the non-gelatinous groups contributed the most total abundance. Correlation analysis suggests that the non-gelatinous zooplankton biomass and abundance had a significant positive correlation in the whole year, but the relationship was insignificant between the total zooplankton biomass and abundance in spring and summer. The diversity index H of zooplankton community averaged 1.88 in this study, which was somewhat higher than historical results. Relatively low diversity in summer was related to the high dominance of Calanus sinicus, probably due to the strongest effect of the HSCWM in this season.  相似文献   

3.
2008年初冷事件对南海北部夏季浮游动物的影响   总被引：1，自引：0，他引：1  
2008年初,我国南方出现了罕见的低温冰冻极端天气过程。通过对2007年8月和2008年8月南海北部现场调查所获得的数据分析研究了浮游动物种类组成。结果表明,与2007年8月相比2008年8月浮游动物丰度和生物量有很大的下降。聚类分析结果表明浮游动物群落被分为近岸和远海两大类群。浮游动物近岸类群和远岸类群的分界点在不同的时间有所不同,这是由于外海水向近岸的入侵所致。与2007年8月相比,2008年8月浮游动物优势种发生了很大的演替,主要是因为四种浮游动物优势种亚强真哲水蚤、异尾宽水蚤、锥形宽水蚤和小哲水蚤丰度急剧下降所致。相反,水母类和海樽类丰富有很大的升高,其原因可能是2008年春季极端低温导致的鱼类大量死亡所致。与远岸浮游动物群落相比,近岸浮游动物群落变化更剧烈,这说明近岸浮游动物群落结构不稳定。南海北部浮游动物群落结构的变化与2008年初的冷事件有很大关系。  相似文献   

4.
Processes underlying the temporal and spatial variations observed in the distribution of jellyfish and non‐gelatinous zooplankton in the Gulf of Oman are not well understood. This information gap is clearly a major issue in controlling the harmful blooms of jellyfish and non‐gelatinous zooplankton. Samples of jellyfish and non‐gelatinous zooplankton were collected from six stations in Chabahar Bay and three stations in Pozm Bay within four seasons. At each station, environmental variables were also recorded from bottom and surface water. A total of 83 individuals of medusae representing four species of Scyphozoa (i.e., Cyanea nozakii, Chrysaora sp., Pelagia noctiluca, Catostylus tagi) and species of Hydrozoa (i.e., Diphyes sp., Rhacostoma sp., Aequorea spp.) were observed in the study area. A total of 70,727.25 individuals/m?3 of non‐gelatinous zooplankton dominated by copepods and cladocerans were collected in nine stations within the four seasons. The results of a RELATE analysis yielded no significant association between species composition for jellyfish and non‐gelatinous zooplankton. Among environmental variables, water transparency, nitrite concentration, water depth and temperature were better associated with the total variation in jellyfish species composition than with that of non‐gelatinous zooplankton. Dissolved oxygen, pH, and phosphate concentration were significant environmental variables associated with the variation in the spatial and temporal distribution patterns of non‐gelatinous zooplankton assemblages. Although some jellyfish species (i.e., Rhacostoma sp., Pelagia noctiluca, Catostylus tagi) occur independently of non‐gelatinous zooplankton assemblages, other jellyfish (i.e., Chrysaora sp., Aequorea spp., Cyanea nozakii, Diphyes sp.) are strongly correlated with non‐gelatinous zooplankton assemblages.  相似文献   

5.
为了探究不同种类水母对浮游食物网的摄食影响,采用碳氮稳定同位素和脂肪酸标记法,研究分析了渤海红沿河海域常见的4种小型水母(伞径直径5 cm:卡玛拉水母Malagazzia carolinae、球形侧腕水母Pleurobrachia globosa、帽铃水母Tiaricodon coeruleus、半球美螅水母Clytia hemisphaerica和3种大型水母(伞径10—200cm:沙海蜇Nemopilema nomurai、海月水母Aurelia aurita)和白色霞水母Cyanea nozakii)的食物组成。结果表明,不同种类水母的食物组成存在差异。其中卡玛拉水母、球形侧腕水母、帽铃水母、半球美螅水母和白色霞水母均偏肉食食性,食物组成中动物性食物所占比例更高,高于海月水母与沙海蜇。在食物粒径谱上,帽铃水母和半球美螅水母较大粒径的食物比例均高于小粒径的悬浮有机物(POM)比例。卡玛拉水母和球形侧腕水母各个粒径食物比例接近。大型水母中,白色霞水母的食物中大粒径的浮游动物的比例高于海月水母,更高于沙海蜇。由此看来,小型水母和大型的白色霞水母的暴发会直接影响大中型浮游动物数量,海月水母的暴发对不同大小的浮游生物均会产生一定的影响。而沙海蜇的暴发会大量摄食1 mm的小型浮游生物和POM,对大中型浮游动物以及更高营养层生物(鱼类等)的影响可能是通过蜇伤以及饵料竞争导致的。因此,不同种类水母暴发对浮游生物的影响存在差异。本研究从摄食角度初步探究了水母对海洋生态系统物质循环和能量流动的影响,为水母暴发的灾害防治提供了数据支持。  相似文献   

6.
Chrysophaeum taylorii Lewis & Bryan (Pelagophyceae) is a mucilage‐producing benthic microalga that has recently begun to spread in the Mediterranean Sea, where a range expansion is occurring. This paper presents the results of three field experiments that aimed to increase the knowledge on mucilage provision mechanisms for this benthic microalga and to evaluate the importance of mucilage in its range expansion. By means of two correlative field experiments (several years of data were considered to encompass the variability of mucilage cover) we found that, on the sea bottom, mucilage cover does not depend on epilithic cell density and that both its cover and settling are affected by water flow. We also tested the hypothesis that cells embedded in floating mucilage fall on the underlying substratum, where their abundance depends on water flow. To this aim, in the field we manipulated the presence of floating mucilaginous aggregates in cages with different levels of exposure to winds. The abundance of C. taylorii cells on the substratum under cages with mucilage was compared with that of two control treatments: cages without mucilage and mucilage in still water, in the field and lab, respectively. The results suggested that mucilage can represent an excellent strategy for the species to disperse, as C. taylorii cells fall from the floating mucilage and, if the water flow is unimportant, settle on hard substrata just underneath the cage. This study enriches the portfolio of knowledge of the dispersal strategies of microalgae and contributes to the understanding of the spread of invasive species.  相似文献   

7.
初夏南黄海浮游动物功能群丰度年际变化   总被引：2，自引：1，他引：1  
利用1959年和2000—2009年6月份在南黄海海域进行的7个航次海洋调查采样样品,并结合同步温盐资料及海温长期变化数据,研究了不同浮游动物功能群丰度的年际变化。结果表明:大型甲壳类和毛颚类功能群丰度高且波动幅度较大,在1959年和2000—2009年两个时期无明显差异,最低值分别出现在2003年和2000年;而中华哲水蚤为优势种的大型桡足类功能群丰度在2000—2009年显著高于1959年,波动范围分别在2035—24500和912—1330ind/m2之间;小型水母和海樽类功能群丰度一般较低,但是在2007年出现暴发式增加,平均丰度分别是其它年份中最高平均丰度的4.8倍和88.5倍。大型甲壳类和毛颚类分别在东部冷水团区和中部锋面区波动幅度最大,小型水母和海樽类则是在西部浅水区波动幅度最大。分析认为桡足类丰度增加与营养盐浓度升高和鱼类过度捕捞有关,而胶质生物种群剧烈波动与气候变化引起的环境变异相关。  相似文献   

8.
The decoupling of trophic interactions could be one of the severe consequences of climate warming in aquatic systems. The timing of phytoplankton blooms, in particular, can affect competition within the plankton community as well as food-web interactions with zooplankton and fish. Using long-term data from Helgoland Roads in the southern North Sea, we examine diatom seasonality, using three representative diatom species combined with environmental and copepod time series over the last four decades. The long-term annual abundances of Guinardia delicatula, Thalassionema nitzschioides and Odontella aurita exhibited interannual variations and dissimilar cyclic patterns during the time period under study (1962-2008). Of the three diatoms, G. delicatula showed a significant trend towards earlier bloom timings for 1962-2008 and a later decline of its abundance over time was found. Grazing and water transparency explained most of the bloom timing fluctuations of the diatoms considered. The annual timing of occurrences of each diatom species was correlated with their preceding concentrations. Earlier bloom timings occurred when autumn/winter concentrations were higher than average and later bloom timings occurred when autumn/winter concentrations were lower than average. Different environmental and predation variables related to the diatom bloom timings were found suggesting that climate warming might not affect the onset of the blooms of the three diatom species in the same manner. The results of the multiple linear regression analyses showed that the timings of decline of the three diatoms were mainly correlated with decreasing nutrient concentrations. Sunshine duration could prolong the duration of the blooms of T. nitzschioides and O. aurita provided that enough nutrients were available. In the case of G. delicatula, however, sunshine duration was negatively correlated with its end of the growth period. G. delicatula and T. nitzschioides showed later decreases in abundances under warmer spring and summer temperatures. Such species specific differences in the sensitivity to the forcing variables could lead to shifts in community structure and could ultimately have wider implications to the overall ecosystem health of the North Sea.  相似文献   

9.
根据2018年1月(冬季)、4月(春季)、7月(夏季)和11月(秋季)在宁德晴川湾海域浮游动物调查的4个航次数据,分析该海域水母群落结构和季节变化特征,讨论了水母对宁德晴川湾核电站安全生产潜在的风险。结果表明:宁德晴川湾海域水母类种类组成、丰度分布和优势种演替均存在季节变化,春、夏、秋、冬该海域水母种数分别为7种、16种、9种和3种,丰度均值分别为(45.48±8.24)个/m3、(50.26±12.13)个/m3、(3.68±1.91)个/m3和(0.18±0.07)个/m3,首要优势种分别为印度感棒水母(Laodicea indica)、球型侧腕水母(Pleurobrachia globosa)、双生水母(Diphyes chamissonis)和耳状囊水母(Euphysa aurata),优势种类组成季节演替明显。春季和夏季水母的丰度与浮游动物的总丰度呈极显著相关,在夏季其数量与浮游动物中的桡足类数量呈显著相关(p<0.05,R=0.363),秋季和冬季水母群落的丰度主要受盐度的影响。秋、冬季该海域盐度、温度均较低,水母的丰度也较低。根据宁德晴川湾核电站附近海域水母分布特征,以水母丰度50 个/m3为风险阈值考虑,夏季为潜在高风险季节,需重点关注距核电站冷源取水口5～20 km海域;其次是春季,重点关注距取水口2.5～5 km海域;秋季和冬季基本不会因水母而引起核电站冷源安全事故发生。  相似文献   

10.
秋季南黄海浮游动物分布及其影响因素   总被引：3，自引：1，他引：2  
王晓  姜美洁  刘萍  张学雷  王燕  王宗灵 《海洋学报》2016,38(10):125-134
基于2007年秋季在南黄海（32°20'~37°00'N;124°E以西）进行的浮游动物及环境因子大面调查;分析了秋季南黄海浮游动物种类组成、分布特征及其影响因素;主要结果如下:共鉴定浮游动物113种（不包括25种浮游幼体）;中华哲水蚤（Calanus sinicus）、强壮滨箭虫（Aidanosagitta crassa）、磷虾幼体（Euphausia larvae）和小齿海樽（Doliolum denticulatum）是秋季优势种;浮游动物丰度为（156.37±12.04）ind/m3;生物量为（172.57±10.41）mg/m3;与历史调查数据相比;本航次浮游动物丰度和生物量相对处于较高水平;磷虾幼体分布趋势与中华假磷虾（Psudeuphausia sinica）一致;说明秋季是中华假磷虾种群的一个重要的补充时期;小齿海樽在南黄海的大量出现系自身种群补充的结果;精致真刺水蚤（Euchaeta concinna）和肥胖软箭虫（Flaccisagitta enflata）主要分布在深水区;在近岸海区很少出现。中华哲水蚤、强壮滨箭虫丰度高值区倾向分布于海洋锋附近;进一步佐证了海洋锋对浮游动物的积聚作用。  相似文献   

11.
Abstract. Seasonal changes in zooplankton biomass, abundance and species composition were studied at a neritic station in the Balearic Sea between April 1993 and May 1994. Sampling was carried out every 10 days in a zone influenced by the main current circulating through the Mallorca channel. Three main peaks of zooplankton biomass and abundance were observed: (1) at the beginning of summer when the thermocline developed, (2) in autumn when the thermocline broke down, and (3) in early spring. The smaller zooplankton fraction (100–250 μm) comprised on average 32 % of the total biomass and 73 % of total abundance. Copepods were the predominant group (64 % of the total abundance) with Clausocalanus, Oithona and Paracalanus being the most abundant genera. Paracalanus parvus, Clausocalanus furcatus, Acartia clausi, Oithona plumifera, Temora stylifera, Centropages typicus and Oncaea mediterranea were found to be the most important species in the area. Other abundant groups were cladocerans (15 %) and meroplankton larvae (12 %), both of which were particularly numerous during the stratified period. The copepod community was characterized by the above‐cited perennial species, which were abundant during the cycle studied. However, the influence of the hydrological conditions of the Balearic Sea, such as the Atlantic water influx and the physical structure of the water column (stratification and mixing), promoted the observed variability in zooplankton as well as the appearance of characteristic species during the annual cycle.  相似文献   

12.
The bioacoustics of upper waters of the Black Sea, the Sea of Marmara, and the Mediterranean Sea were studied in October 1999 with an echosounder with 120 and 200 kHz dual‐beam transducers. Net tows were taken to ground‐truth the acoustic volume backscattering. A forward solution was applied to determine significant scatterers of the three seas with regard to detection limits of the frequencies and background noise measured in each sea. The noise was 4 dB higher in the Sea of Marmara than in the other two seas. 200 kHz data showed significant correlation between measured and calculated volume backscattering strength, and density (biomass and abundance) of the taxa. Large‐sized copepods and chaetognaths in the Black Sea, Aurelia, Beroe, chaetognaths and large‐sized and abundant appendicularians in the Sea of Marmara, and fish larvae in the Mediterranean Sea contributed most to the volume backscattering.  相似文献   

13.
北黄海獐子岛海域浮游动物群落年际变化   总被引：1，自引：0，他引：1  
本文比较了海洋普查期间（1959年1-12月）和2009-2010年獐子岛海域附近站位的浮游动物的种类组成、优势种、丰度、生物多样性,结果显示,北黄海区域浮游动物群落物种组成未发生较大的变化,在獐子岛海域以及整个北黄海,中华哲水蚤和强壮箭虫的优势种地位没有发生变化,细足法虫戎也一直出现且为冬春季的优势种;太平洋磷虾在2009-2010年獐子岛海域虽然全年均有出现,但是全年均不是优势种,而在1959年的獐子岛海域,作为优势种出现在4月和11月;1959年与2009年相较,腹针胸刺水蚤在春夏季优势种的地位被沃氏纺锤水蚤所取代。2009年浮游动物丰度（131.26 ind/m3）比1959年（78.90 ind/m3）高;浮游动物多样性指数（H'）均在夏秋季高于冬春季节,且年平均多样性指数也有所提高。  相似文献   

14.
The monthly abundance, biomass and taxonomic composition of zooplankton of Izmit Bay (the northeastern Marmara Sea) were studied from October 2001 to September 2002. Most species within the zooplankton community displayed a clear pattern of succession throughout the year. Generally copepods and cladocerans were the most abundant groups, while the contribution of meroplankton increased at inner-most stations and dominated the zooplankton. Both species number (S) and diversity (H′) were positively influenced by the increase in salinity of upper layers (r = 0.30 and r = 0.31, p < 0.001, respectively), while chlorophyll a was negatively affected (r = −0.36, p < 0.001). Even though Noctiluca scintillans had a significant seasonality (F11,120 = 8.45, p < 0.001, ANOVA), abundance was not related to fluctuations in temperature and only chlorophyll a was adversely correlated (r = −0.35, p < 0.001). In general, there are some minor differences in zooplankton assemblages of upper and lower layers. A comparison of the species composition and abundance of Izmit Bay with other Black Sea bays reveals a high similarity between them.  相似文献   

15.
Biological and physical surveys were conducted in order to investigate the relationship between environmental conditions and the distribution of moon jellyfish Aurelia aurita in Hiroshima Bay, western Seto Inland Sea, Japan. Moon jellyfish and ichthyoplankton were collected at 13 stations in Hiroshima Bay during monthly surveys from July to September in 2006 and 2007. Surface temperature in 2006 was significantly lower during the August and September cruises and surface salinity was lower during all cruises than in 2007. Moon jellyfish was the most dominant gelatinous plankton collected, accounting for 89.7% in wet weight. Mean moon jellyfish abundance in 2006 was higher than that in 2007 from July through September, with significant inter-year differences for July and September. Variability in precipitation and nutritional input from the Ohta River, northernmost part of Hiroshima Bay, were suggested as possible factors affecting the inter-annual variability in moon jellyfish abundance in the coastal areas of northern Hiroshima Bay. Moon jellyfish were more abundant in the coastal areas of northern Hiroshima Bay, where the dissolved oxygen (DO) concentration was lower, while low in the central part of the bay. Japanese anchovy Engraulis japonicus eggs were most dominant (58.1% in number) among the ichthyoplankton and were abundant in the central area of Hiroshima Bay. Explanatory analysis was conducted to detect possible effects of environmental conditions on the abundance of moon jellyfish and Japanese anchovy eggs during the summer months in Hiroshima Bay. Of the environmental conditions tested (temperature, salinity and DO of surface and bottom layers at each sampling station), bottom DO had the most significant effect on the moon jellyfish abundance: there was a negative correlation between the bottom DO and the moon jellyfish abundance in Hiroshima Bay during summer.  相似文献   

16.
We present the results of the first study to highlight the demography, morphometry and growth rates of Spinimuricea klavereni, a rare Mediterranean endemic gorgonian exceptionally common in shallow depths of the Northeast Marmara Sea. In the study area, this species forms vast populations on rocks, boulders and attached to pebbles/stones/shells on soft substrates between 20 and 45 m depth, with a total average density of 0.3 colonies·m?2 but comprising patches up to 3 colonies·m?2. Colonies, which are on average 42.9 (±20.1) cm in height, can reach up to 110 cm. Unlike other Mediterranean gorgonians, the colonies studied here showed fast growth rates that decreased with increasing colony height, between 1.5–11.1 and 4.96 ± 3.01 cm·year?1 on average. The low necrosis and high growth rates displayed by this species in the Northeast Marmara Sea confirm the previously hypothesized opportunistic behaviour of the species. The unique community consisting of S. klavereni and other rare gorgonian/soft corals has limited distribution in this area and should be considered to be a vulnerable marine ecosystem. Therefore we recommend that some conservation measures are taken, including the prohibition of all fisheries and anchoring over these assemblages.  相似文献   

17.
An integral concept of ecological research is the constraint of biodiversity along latitudinal and environmental gradients. The Red Sea features a natural example of a latitudinal gradient of salinity, temperature and nutrient richness. Coral reefs along the Red Sea coasts are supported with allochthonous resources such as oceanic and neritic phytoplankton and zooplankton; however, relatively little is known about how the ecohydrography correlates with plankton biodiversity and abundance. In this article we present the biodiversity of phytoplankton and zooplankton in Red Sea coral reefs. Oceanographic data (temperature, salinity), water samples for nutrient analysis, particulate organic matter, phytoplankton and zooplankton, the latter with special reference to Copepoda (Crustacea), were collected at nine coral reefs over ~1500 km distance along the Red Sea coast of Saudi Arabia. The trophic state of ambient waters [as indicated by chlorophyll a (Chl a)] changed from strong oligotrophy in the north to mesotrophy in the south and was associated with increasing biomasses of Bacillariophyceae, picoeukaryotes and Synechococcus as indicated by pigment fingerprinting (CHEMTAX) and flow cytometry. Net‐phytoplankton microscopy revealed a Trichodesmium erythraeum (Cyanobacteria) bloom north of the Farasan Islands. Several potentially harmful algae, including Dinophysis miles and Gonyaulax spinifera (Dinophyceae), were encountered in larger numbers in the vicinity of the aquaculture facilities at Al Lith. Changes in zooplankton abundance were mainly correlated to the phytoplankton biomass following the latitudinal gradient. The largest zooplankton abundance was observed at the Farasan Archipelago, despite high abundances of copepodites, veligers (Gastropoda larvae) and Chaetognatha at Al Lith. Although the community composition changed over latitude, biodiversity indices of phytoplankton and zooplankton did not exhibit a systematic pattern. As this study constitutes the first current account of the plankton biodiversity in Red Sea coral reefs at a large spatial scale, the results will be informative for ecosystem‐based management along the coastline of Saudi Arabia.  相似文献   

18.
In October 2005 spatial distribution of live and dead Acartia clausi and Acartia tonsa was studied in the Black and Marmara Seas and near the Marmara Sea inlet of the Bosphorus, in order to understand their fate upon transportation between two seas. The morphometric characteristics in both species from all studied areas, and the decreased abundance of A. clausi and A. tonsa from the Black Sea towards the Marmara Sea indicate that the Marmara Sea Acartia populations are formed by recruitment from the Black Sea. We observed mass mortality of A. clausi in the Marmara Sea near the Prince Islands. The majority of carcasses (66% of total A. clausi numbers in the Marmara Sea) were found in the salinity gradient layer.  相似文献   

19.
广东省南澳海域是粤东重要的海产养殖基地, 分析该海域浮游动物群落结构特征对评估其生态环境质量具有重要意义。文章根据2014年9月(秋季)、12月(冬季)、2015年4月(春季)和2016年7月(夏季)在南澳岛东部海域的浮游动物调查, 分析该海域浮游动物的群落结构特征, 探讨环境因素对其时空分布的影响。共鉴定浮游动物206种(包括浮游幼虫), 桡足类种数最多, 达94种; 远岸海域浮游动物的种数高于近岸海域。浮游动物丰度和生物量的季节变化明显, 夏、秋季高于冬、春季; 浮游动物丰度和生物量的分布趋势较一致, 夏季高值区主要出现在近岸, 秋季由近岸向远岸海域递增。浮游动物不同类群和优势种的丰度也存在季节变化, 桡足类是调查期间丰度较高的类群, 秋季水母类和海樽类丰度明显增加; 优势种后圆真浮萤(Euconchoecia maimai)和针刺真浮萤(Euconchoecia aculeata)在夏季丰度高, 小齿海樽(Doliolum denticulatum)在秋季占绝对优势。温度、盐度和浮游植物生物量是影响南澳岛东部海域浮游动物时空变化的主要环境因子, 说明该海域浮游动物群落特征受海流、水团和养殖活动的综合影响。  相似文献   

20.
崇明东滩潮沟浮游动物数量分布与变动   总被引：3，自引：0，他引：3  
根据2008年4-12月对上海市崇明岛东滩潮沟进行4个季节的浮游动物调查资料,研究了崇明东滩潮沟浮游动物的数量分布及变动。结果表明,调查区浮游动物总丰度较高,四季变化明显。受潮汐作用的影响,夏、秋、冬三季落潮时丰度大于涨潮时,春季涨潮时丰度则大于落潮时。浮游动物在6条潮沟的平面分布不均匀,春季东旺沙边滩区和北八边滩区的数量明显多于近团结沙边滩区,夏、秋季分别以东旺沙边滩区和北八滧边滩区的数量最多,冬季则以近团结沙边滩区的数量最多。主要优势种细巧华哲水蚤(Sinocalanus tenellus)、中华华哲水蚤(Sinocalanus sinensis)、火腿许水蚤(Schmackeria poplesia)、四刺窄腹剑水蚤(Limnoithona etraspina)和四刺破足猛水蚤(Mesochra quadrispinosa)等数量的季节、潮汐变化及各时期的空间分布格局差异明显,其数量分布情况决定了浮游动物总数量的分布。盐度是影响冬、春季涨潮时浮游动物总丰度分布的主要因子,水温则是影响夏、秋季涨潮时总丰度分布的主要因子。此外,径流及潮流等动力因素对潮沟浮游动物数量的时空分布也产生重要影响。  相似文献   

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