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1.
Concerning the ecological studies of the Hydromedusae and Ctenophores in Taiwan Strait, we have only two papers available on these studies in the southwest of Taiwan Strait. Throughout the western Taiwan Strait, for the first time the paper reports species composition, seasonal change, hori zontal distribution, ecological characteristics of the Hydromedusae and Ctenophores and their relationship to the environmental factors. 相似文献
2.
利用2003年6月和2006年6月在长江口及邻近海域进行的两次大面调查所采集的浮游动物网采样品,对长江口及邻近海域水母类的种类组成、优势种、数量分布及生态类群等进行了探讨。结果表明:研究水域共记录水母类77种,其中水螅水母60种,管水母12种,钵水母1种,栉水母4种。优势种有:五角水母(Muggiaea atlantica),双生水母(Diphyes chamissonis),拟细浅室水母(Lensia subti-loides),四叶小舌水母(Liriope tetraphylla),两手筐水母(Solmundella bitentachlata),嵊山秀氏水母(Sugiura chengshanense)和瓜水母(Bere cucumis)等。其中水螅水母类的优势种存在较大的年际变化,2003年为嵊山秀氏水母,2006年为四叶小舌水母和两手筐水母。研究水域内水母类平面分布不均匀,2003年平均丰度为13.3个/m3,除在长江口外存在一个由河口低盐种贝氏拟线水母(Nemopsis bachei)大量聚集形成的高值区外,在舟山群岛南部还存在一个密集中心;2006年水母类丰度略有上升,平均丰度为16.0个/m3,与2003年相比,其密集中心向东北部偏移。2006年6月研究海域温、盐较2003年同期均大幅升高是造成两航次优势种类更替及水母类分布变化的主要原因。 相似文献
3.
Gelatinous zooplankton species composition, distribution and abundance were investigated in the bay and the lagoon of Bizerte (North Tunisian coast) from January 2004 to December 2005. In total, 48 species were identified in the study area: 24 medusae, 11 siphonophores, four appendicularians, six chaetognaths, two pteropods and one doliolid. The hydromedusa Eutima mira was recorded for the first time in the Western Mediterranean Sea. The diversity in the Bay of Bizerte was greater than the diversity in the Bizerte lagoon. There was a loss of species diversity. Siphonophores were the most sensitive group to anthropogenic discharge. Only two species of siphonophores were recorded in the lagoon. Four species of gelatinous zooplankton, Muggiaea kochi, Lensia conoidea, Oikopleura longicauda and Podocorynoides minima were the most frequent species in the lagoon and may benefit from eutrophication. Appendicularians were numerically the most dominant group in the bay and the lagoon of Bizerte. Mesozooplankton density declined significantly in autumn and winter of 2004 and 2005 in relation to the dense aggregations of the scyphomedusae Pelagia noctiluca. Statistical analysis divided the study area into three zones: lagoon zone, bay zone and channel zone. 相似文献
4.
通过1999年和2010年夏季同期7月在白令海(169°E~166°W,50°N~67°N)获取的94份浮游植物样品分析,获得了近十年的始末两个时间节点的浮游植物群落结构与时空变化,探讨了浮游植物群落动态及其与环境因素的关联。研究结果显示,共鉴定浮游植物(>10μm)5门58属153种,分为3个生态类群。硅藻是浮游植物的主体,种类多丰度高,占总种类数目的66.7%,占总丰度的95.2%。鉴于样品属性和空间范围的不同,物种组成有细微差别,丰度有较大差异且空间分布明显不同,高丰度区受控于上层营养盐供给和表层环流系统。优势种从北方温带大洋性硅藻演变为广温广盐性与冷水性硅藻,1999年以西氏新细齿状藻为第一优势种,柔弱伪菱形藻次之;2010年以丹麦细柱藻为第一优势种,冷水性的诺登海链藻次之并在陆架和陆坡占优。浮游植物群落结构较为稳定,由深水群落和浅水群落组成。深水群落分布于太平洋西北部和白令海盆,种类组成以温带大洋性的西氏新细齿状藻、长海毛藻、大西洋角毛藻和广布性的菱形海线藻、扁面角毛藻、笔尖根管藻为主,丰度低,种间丰度分配均匀,优势种多元化,物种多样性高;浅水群落分布于白令海陆坡和陆架,主要由冷水性的诺登海链藻、叉尖角毛藻、聚生角毛藻和广布性的丹麦细柱藻、旋链角毛藻组成,丰度高,种间丰度分配不均匀,优势种突出,物种多样性低。白令海夏季浮游植物种类组成及丰度变化直接受控于表层环流、营养盐、春季冰缘线等环境因素。 相似文献
5.
During the 1990s many studies on zooplankton in the Japan Sea have been carried out. In this review, I have synthesized the study of horizontal distribution, seasonal and annual variations of zooplankton biomass, and ecological characteristics of major component species in the southern Japan Sea, which area is influenced by the warm Tsushima Current. The zooplankton biomass (annual mean) in the southern Japan Sea was lower than in the subarctic Pacific, including the northern Japan Sea, and similar to biomass levels in Kuroshio waters. Temporal variations in zooplankton biomass showed both seasonal and year-to-year components. Seasonal biomass increases to a maximum in spring with a weak secondary peak in autumn. As for long-term changes, 3–6 year cycles were identified, with the dynamics of the surface warm Tsushima Current and the subsurface cold water playing important roles in determining the yearly zooplankton community structure and biomass. Cold water species in the southern Japan Sea had extensive diel vertical migrations whose range is restricted in summer by the development of a thermocline. Among these species, the herbivores Euphausia pacifica and Metridia pacifica encounter a lower food supply, resulting in lower growth rates. The vertical dispersal of epipelagic carnivorous zooplankton such as Sagitta elegans and Themisto japonica to the deep-sea is probably facilitated by reduced interspecific competition. Their interaction with Japan Sea Proper Water, characterized by near-zero temperatures in the meso- and bathypelagic zones suppresses growth rates of the mesopelagic zooplankton. The lack of micronektonic predators in the mesopelagic zone may allow the persistence of slow growing populations. 相似文献
6.
黄河季节性入海径流所携入的淡水、泥沙及营养物质，与渤海海洋环境相互作用，因而形成了黄河口及邻近水域多种经济种类的产卵场和育幼场。然而，近代黄河尾闾不断变化，加上近年来黄河水资源过度利用和上游生态环境恶化所引起的断水断流，导致了冲淡水和营养盐来源短缺。研究表明，黄河口及邻近海域的生态环境质量，将直接影响到渤海，乃至黄海生物资源动态及其可持续性(乐肯堂，1995;乐肯堂等，1995;沈志良等，1989; Yang et al.，1993)。在过去的20年内，许多研究人员曾进行过多次渤海水域生态环境和渔业资源综合调查。朱鑫华(1996，1998)曾就20世纪80-90年代进行的两次调查资料对渤海鱼类群落的时空格局进行了因子分析，指出渤海3湾的鱼类群落演替呈现较不稳定性格局。本文结合以上调查及其相关研究项目，以1982-1985年的周年调查资料为本底资料，重点研究黄河口及邻近水域鱼类群落生态密度结构特征；结合20世纪90年代现场比较调查资料，分析生物资源对黄河水、沙等生态环境变化的响应特征。 相似文献
7.
Zooplankton surveys were carried out on November 2-3 and December 8-10, 2001 at 12 stations in the Nan Wan Bay of Taiwan, China. Altogether 92 quantitative zooplankton samples were collected from subsurface water and bottom water layers with two conical plankton nets （180 cm in length, 45 cm in opening diameter, 333μm and 200 larn in mesh size）. A total of 31 species of Siphonophores were identified, among them 7 species are new records in the waters around Taiwan Island, of which Rocacea cymbiformis is a new record in China. Dominated by Chelophyes appendiculata, Bassia bassensis, Diphyes bojani, Diphyes dispar, Abylopsis eschscholtzi and Chelophyes contorta, these species accounted for over 76 % and 63 % of the total abundance in November and December. The species number and Siphonophores abundance in December （25 species, 1.99 inds/m3） were more than those in November （19 species, 0.438 inds/m3）, and they were more in the surface water layer than in the bottom layer at most sampling stations. In early winter, the offshore high salinity water mass was a main factor influencing the distribution. The sampling efficiency for two plankton nets is discussed and the seasonal variation of species number and abundance in the Nan Wan Bay is compared with that in the neighboring waters. 相似文献
8.
许振祖 《海洋学报(英文版)》1983,2(1):129-138
In the survey area, there are four maxima and two clear minima of seasonal variation in total numbers of individuals of hydromedusae a year. The change of locations in the dense center of hydromedusae shows that it moves northward from southwest in spring and summer, and it retracts from north to southwestern part of the strait in autumn and winter. The seasonal variation in number of species of hydromedusae may be divided into two types: ( i ) species occur throughout the year. (ii) species with markedly seasonal variation. There are three dominant species in the survey area, i. e. Liriope tetraphylla, Aglaura hemistoma and Rhopalonema velatum. The former two are of oceanic eurytopic type, the last one is of oceanic steurotopic type. The hydromedusae in investigated area may be divided into three ecological groups, i. e. neritic warm-water, oceanic warm-water and neritic warm-temperal, the former two of which are dominated. 相似文献
9.
印尼穿越流区现代浮游有孔虫四个属种壳体的稳定碳、氧同位素及其意义 总被引：1，自引：0，他引：1
Horizontal and vertical distributions of δ~(18)O and δ~(13)C were investigated in shells of four planktonic foraminiferal species, Globigerinoides ruber, Globigerinoides sacculifer, Pulleniatina obliquiloculata and Neogloboquedrina dutertrei, from a total of 62 core-top sediment samples from the Indonesian throughflow region. Results were compared to modern hydrologic conditions in order to explore potential of proxies in reconstructing fluvial discharge and upper ocean water column characteristics in this region. Our results show that, in the Makassar Strait, both of depleted δ~(18)O and δ~(13)C of these four species were linked to freshwater input. In the Bali Sea,however, depleted δ~(18)O and δ~(13)C for these species may be due to different reasons. Depleted δ~(18)O was a result of freshwater input and as well influenced by along-shore currents while depleted δ~(13)C was more likely due to the Java-Sumatra upwelling. Comparison of shell δ~(18)O records and hydrographic data of World Ocean Atlas 2005 suggests that G. ruber and G. sacculifer calcify within the mixed-layer, respectively at 0–50 m and 20–75 m water depth, and P. obliquiloculata and N. dutertrei within the upper thermocline, both at 75–125 m water depth. N.dutertrei calcifies at slightly deeper water depth than P. obliquiloculata does. In general, δ~(13)C values of both G.ruber and G. sacculifer are larger than those of P. obliquiloculata and N. dutertrei at all sites, possibly related to depth habitats of these species and vertical distribution of nutrients in the Indonesian throughflow region. 相似文献
10.
根据2019年1月、4月、7月和10月四个季度10个站位定置张网调查资料, 对福建三沙湾游泳动物的种类组成及季节变化进行分析研究。结果表明: 调查共获得游泳动物209种, 隶属于3门4纲19目73科144属, 其中鱼类154种, 甲壳类48种, 头足类7种。游泳动物种类数以秋季出现最多, 四个季节共同出现的种类有42种。鲈形目种类最多, 其次是十足目。鱼类适温性以暖水性种类居多, 占71.43%, 暖温性种类次之(27.92%); 生态类型以底层、近底层鱼类居多, 两者合占75.97%。鹰爪虾(Trachypenaeus curvirostris)、大黄鱼(Larimichthys crocea)、棘头梅童鱼(Collichthys lucidus)、红星梭子蟹(Portunus sanguinolentus)和日本蟳(Charybdis japonica)等14个种类是三沙湾游泳动物的优势种类, 季节性优势种居多。三沙湾定置张网调查渔业资源质量密度为111.09 kg/km2, 尾数密度为13.72×103 ind./km2, 均以夏季最高, 春季最低。应该进一步加强对三沙湾渔业资源的合理利用和有效保护, 同时重视对外来物种的监测。 相似文献
11.
12.
WANG Chunguang HUANG Jiaqi XIANG Peng WANG Yanguo XU Zhenzu GUO Donghui LIN Mao 《海洋学报(英文版)》2014,33(6):95-102
Fifty-seven stations(48 grid stations and nine stratified stations) were sampled across the study region(67.000°–88.394°N, 152.500°–178.643°W) during the 4th Chinese National Arctic Research Expedition(CHINARE 4) from July to August 2010 by the icebreaker R/V Xuelong. A total of 24 species of Hydromedusae were identified from 130 zooplankton samples, of which seven species belonged to Automedusa, eight species to Anthomedusae, four species to Leptomedudae, and three species to Siphonophora. Catablema multicirratum Kishinouye, 1910, Bougainvillia bitentaculata Uchida, 1925, and Euphysa japonica(Maas, 1909) were recorded for the first time in the Arctic sea. In the present paper, 18 species of Hydromedusae were described and illustrated, of which three species were described for the first time in the Arctic sea, and 15 species were described for the first time in China. 相似文献
13.
Biomass distribution and trophodynamics in the oceanic ecosystem in the Oyashio region are presented and analyzed, combining
the seasonal data for plankton and micronekton collected at Site H since 1996 with data for nekton and other animals at higher
trophic levels from various sources. The total biomass of biological components including bacteria, phytoplankton, microzooplankton,
mesozooplankton, micronekton, fishes/squids and marine birds/mammals was 23 g C m−2, among which the most dominant component was mesozooplankton (34% of the total), followed by phytoplankton (28%), bacteria
(15%) and microzooplankton (protozoans) (14%). The remainder (9%) was largely composed of micronekton and fish/squid. Marine
mammals/birds are only a small fraction (0.14%) of the total biomass. Large/medium grazing copepods (Neocalaus spp., Eucalanus bungii and Metridia spp.) accounted for 77% of the mesozooplankton biomass. Based on information about diet composition, predators were assigned
broadly into mean trophic level 3–4, and carbon flow through the grazing food chain was established based on the estimated
annual production/food consumption balance of each trophic level. From the food chain scheme, ecological efficiencies as high
as 24% were calculated for the primary/secondary production and 21% for the secondary/tertiary production. Biomass and production
of bacteria were estimated as 1/10 of the respective values for phytoplankton at Site H, but the role of the microbial food
chain remains unresolved in the present analysis. As keystone species in the oceanic Oyashio region, Neocalanus spp. are suggested as a vital link between primary production and production of pelagic fishes, mammals and birds. 相似文献
14.
Seasonal dynamics, environmental preferences and habitat selection of John Dory (Zeus faber) 总被引：1，自引：0，他引：1
C.D. Maravelias E.V. Tsitsika C. Papaconstantinou 《Estuarine, Coastal and Shelf Science》2007,72(4):703-710
Spatial distribution patterns of John Dory (Zeus faber, L.) were examined in relation to sea bottom temperature, bathymetry, locational covariates and season. Data were collected during a 2-year period (1996–1997) of seasonal sampling using demersal trawl surveys in the Aegean Sea (eastern Mediterranean). The ecological preferences of the species throughout four seasons were elucidated and the degree in which these environmental relationships might be modulated by the different hydrographic and topographic regime was also considered. Key determinants of the species' spatial aggregation in all four seasons were the water depth, the sea bottom temperature and the latitude. The sea bottom temperature had a significant effect on seasonal John Dory abundance both directly, as a main effect, and indirectly, through its interactive effect with the water depth. John Dory seasonal abundance was consistently greater in the shallower regions of the area having warmer bottom waters. Results indicated a distinct southward shift as progressing through the year, with peak abundances being observed in gradually lower latitudes of shallow areas as seasons evolved. John Dory appeared to avoid the deeper waters regardless of their bottom temperature and geographic position. The present results also suggested a seasonal pattern of habitat associations for specific locations characterised by weak hydrographic activity. John Dory preferences for certain water depth zones, sea bottom temperatures and substrate types are hypothesized to modulate the seasonal spatial aggregation of the species to preferred grounds. 相似文献
15.
《Oceanologica Acta》2003,26(5-6):645-655
The Medusae of Tunis Gulf (25 species) are qualitatively the third zooplanktonic group after Tintinnids and Copepods. Anthomedusae (eight species), Trachymedusae (five species) and Leptomedusae (four species) represent the major part among the 20 species of Hydromedusae identified during our study (December 1993–November 1995). However, the Limnomedusae (two species) and the Narcomedusae (one species) are poorly represented. In the Bay of Tunis, Obelia spp., the most common and dominant species, command the quantitative fluctuations of Hydromedusae and reach exceptionally the density of 25 800 ind. m–3. Within the Scyphomedusae (five species), Pelagia noctiluca is the most common species which outbreaks in winter and autumn. Tunis Gulf seems to be composed of two jellyfish communities; the first one is composed of endogenous species showing a constant period of blooming like Olindias, Cladonema, Aurelia, Cotylorhiza and Rhizostoma and sometimes permanent like Obelia spp. and Clytia spp.; the second is represented by exogenous species considered as “visitors” like Velella, Sminthea or Pelagia whose presence on the coast is dependent on local and particular winds and currents. 相似文献
16.
作者基于2011年9月(丰水期)和2012年1月(枯水期)粤西近岸30米以浅海域的调查资料,分析该海域浮游植物的种类组成、优势种、丰度及其群落结构多样性。结果表明,调查海域共鉴定浮游植物4门41属116种,硅藻为最主要优势类群。丰水期与枯水期共有种类40种,物种相似性指数为34.48%,表明2个调查季节种类组成变化较大,存在明显的季节性差异。枯水期优势种仅1种,为金藻门(Chrysophyta)的球形棕囊藻(Phaeoecystis globosa),优势度高达0.496;丰水期优势种有4种,其中以硅藻门的旋链角毛藻(Chaetoceros curvisetus)优势度较高(0.249)。浮游植物丰度表现出时间和空间异质性,丰度总体呈现近岸站位高于离岸站位,此外,丰水期浮游植物丰度湛江沿岸站位高于其他调查站位,枯水期浮游植物丰度则由西南部向东北部递减,总体而言,枯水期浮游植物丰度比丰水期高。群落结构多样性为枯水期西南部海域明显低于东北部海域,丰水期站位间多样性无明显变化规律,相比之下,丰水期群落物种多样性水平相对较高。相关分析表明:浮游植物丰度与p H、悬浮物呈正相关,与丰水期水温和枯水期盐度呈负相关。 相似文献
17.
根据2013年3-4月、6-7月、9月和11-12月4个航次的调查资料;分析南沙海域浮游虫戎亚目的种类组成、优势种、栖息密度和群落结构特征;并探讨季风转换对其影响及其与管水母的关系。研究海域内共鉴定浮游虫戎亚目12科26属63种。生态类群结构属于热带大洋性。优势种较少;共出现7种;其中;孟加拉蛮虫戎（Lestrigonus bengalensis）为唯一的年度优势种;优势地位显著。物种组成存在季节性变化;分为春季、夏季与秋-冬季3个群落。虫戎年均栖息密度为18.30×10-2 ind/m3;高数量区主要分布于近岸水域;数量季节变化不明显;但平面分布季节差异明显。虫戎年均丰富度、多样性、均匀度指数和多样性阈值各是1.23、1.28、0.33、0.48。虫戎物种组成随季风转换左右近岸低盐水影响程度而变化;群落结构、生物多样性和栖息密度平面分布随季风转换所驱动的表层环流结构改变而变化。虫戎群落分布与管水母间的相关性证实研究海域两类群物种间的寄宿关系。这种关系促使孟加拉蛮虫戎在沿岸低盐水影响下更易形成高优势度;而表现出类似近岸海域优势种优势地位显著的特点。 相似文献
18.
Lúcia Maria O. Gusmão Xiomara Franchesca G. Diaz Mauro de Melo Jr Ralf Schwamborn Sigrid Neumann‐Leitão 《Marine Ecology》2015,36(1):93-103
Jellyfish are often the most prominent components of plankton, with severe consequences for fisheries and tourism. However, in tropical regions, there is much uncertainty about these consequences due to the lack of basic data. Our objective was to improve the knowledge about jellyfish in the Western Atlantic, with an emphasis on understanding diversity, abundance, and distribution patterns. Samples were collected at 34 stations in 1995 using a 300‐μm‐mesh Bongo net. The 21 species identified belonged to Hydromedusae (11), Siphonophora (nine), and Scyphomedusae (one). The overall mean density was low (5.2 ± 5.3 ind. m?3). Total Hydromedusae biomass was 130.86 mg C m?3, and total Siphonophora biomass was 19.04 mg C m?3. Chelophyes appendiculata (Eschscholtz, 1829) was the most frequent species captured in the oceanic samples, and Aglaura hemistoma (Péron & Lesueur, 1810) was the most common in the neritic region. The latter species is sometimes characterized as a bloom associated with the most polluted and eutrophic river plumes. The main role of jellyfish species in the area is as a higher‐order carnivore. A cross‐shelf significant difference (P < 0.05) was registered, with higher species numbers in oceanic regions and higher densities and biomass in neritic regions. 相似文献
19.
在对南黄海和东海毛颚类生态特征的研究数量分布特征后的续篇.重点探讨调查区毛颚类群落性质和群落结构的特征及与海区环境因子的相关性.结果表明,本区共记录毛颚类28种,种类季节变化不明显,周年共有种达64.3%;但群落优势种则有季节差异与区域差异.毛颚类群落多样性指数(H')和均匀度(J')年均值分别为1.68和0.64.H'的平面分布表现出外部海区大于近岸海区的分布格局.在群落中存在4个生态类群,其中近海暖温带类群和广盐暖水类群可分别指示黄海水、浙江沿岸流和东海陆架混合水在南黄海和东海这两个海区的相互推移和消长过程.此外,从不同侧面的计算分析也表明,影响群落特征值(H')的主要因子是温度和盐度.群落性质是以近岸暖温带低盐种和暖水广布种为主,近岸暖水种和大洋暖水种占一定比例的暖温带-亚热带群落结构的特点. 相似文献
20.
2010年胶州湾网采浮游植物种类组成与数量的周年变化 总被引：2，自引：1，他引：1
为了研究胶州湾网采浮游植物的种类组成与数量变化,作者根据2010年的胶州湾调查资料,对调查区浮游植物丰度、优势种类和季节变化进行分析研究。结果表明,胶州湾浮游植物主要由硅藻和甲藻两大类组成,硅藻占据绝对优势地位。除了7月以外,甲藻/硅藻比均0.2。生态类型主要以近岸广布种和暖温带种为主,在不同季节也出现了少数暖水种和外洋种。浮游植物丰度表现为明显的"双周期",冬、春两季较高,夏、秋两季较低。2月为全年最高峰,数量为1108×104个/m3,10月为夏、秋两季的高峰,数量为458.7×104个/m3。浮游植物群落的多样性指数平均为1.9。 相似文献