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1.
通过在高度富营养化的海水泻湖——厦门贸彗湖开展龙须菜(Gracilaria lemaneiformis)的延绳夹苗挂养与网笼挂养实验和室内端足类啃食海藻实验,探讨了影响筼筜湖龙须菜生长的主要因素。结果显示,筼筜湖龙须菜的表观生长率为0.42%/d,实际生长率为4.80%/d,强壮藻钩虾(Ampithoe valida)的摄食量占龙须菜总生长量的91.4%。而且,筼筜湖的水流缓慢,使藻体附着最高可达2.32g/gFw的颗粒物,明显抑制了龙须菜的生长。以上研究表明,端足类的啃食作用和不良的水动力条件是导致筼筜湖龙须菜表观生长率低的主要原因。  相似文献   

2.
作者在鉴定1994年采自大连(北黄海)浅水和广东大亚湾的端足类(Amphipoda)标本中,发现了蜾蠃蜚科(Family Corophiidae)的一新属,即拟亮钩虾属 Genus Paraphotis,报告如下。新属、新种的模式标本保存在中国科学院海洋研究所。  相似文献   

3.
基于中国第36次南极科学考察期间(2019年12月至2020年1月)于南极宇航员海使用北太平洋网(0.5m~2,330μm)采集的浮游动物样品,对浮游动物的丰度、群落结构、优势种种群结构及其与环境因子之间的关系进行了研究。结果表明:2019/2020年南极夏季宇航员海浮游动物总丰度在8.93—102.00 ind./m3之间,最高丰度记录在宇航员海中部靠北区域,浮游动物主要由桡足类、磷虾、毛颚类、浮游被囊类等类群组成。调查海域桡足类丰度对浮游动物总丰度的贡献可达90%以上,其中、大中型桡足类Calanoides acutus, Metridia gerlachei, Calanus propinquus和Rhincalanus gigas分布广泛,而小型桡足类Oithona similis、Oithona frigida、Ctenocalanus citer、Oncaea conifera等在丰度上占比较高。通过聚类分析可将宇航员海浮游动物在区域上划分为5个群落,普里兹湾涡流、威德尔涡流、南极绕极流南界等物理海洋学过程是宇航员海浮游动物群落分布模式的主要控制因素。另外,生物环境匹配(Bio-env)分析显示,饵料(叶绿素a)也对该海区浮游动物的种群和群落结构具有重要影响。  相似文献   

4.
筼筜湖绿潮期间颗粒有机物及沉积有机物的来源研究   总被引:4,自引:2,他引:2  
以原子碳氮比Cat/Nat、TOC/Chl a、δ13C和δ15N等为指标,分析了筼筜湖绿潮爆发期间悬浮颗粒有机物(POM)和沉积有机物(SOM)的来源。结果显示,筼筜湖的POM主要以外源输入为主。在靠近海水入口的引水渠,POM主要来自厦门西海域的陆源有机碎屑;位于筼筜湖上游的干渠,生活污水及餐饮业废水的有机质是其POM的主要贡献者;内、外湖POM的Cat/Nat(6.94~7.08)与浮游植物接近,但它们并不以浮游植物为主,而主要来自引水渠和干渠有机质的输入。以内湖为例,它们对内湖POM的联合贡献高达54%~97%。筼筜湖SOM的潜在来源多样,但不同湖区差异显著:在大型海藻覆盖区,主要以大型海藻和POM为主,而在无海藻覆盖的区域,则主要来自POM的自然沉降或与底栖微藻的联合贡献。结果表明,在来源复杂的潟湖系统,有机物的化学组成并不能很好的指示有机物的来源和成因,它在有机质的示踪方面并不如稳定同位素来得有效可靠。不过,基于多种指标的分析结果可能更准确。  相似文献   

5.
2009年4~7月,对移入日本对虾养殖池的钩虾和蜾蠃蜚群落进行了研究.共调查到2种钩虾,3种蜾蠃蜚.钩虾的优势种为中华原钩虾;蜾蠃蜚的优势种具有明显的交替性,放养后前53 d,优势种为大蜾蠃蜚,78 d后,优势种为隐居蜾羸蜚.钩虾群落的物种多样性(H')与均匀度(J)在放养当天达到最高,放养后第67天出现差异显著;蜾蠃蜚群落的物种多样性(H')与均匀度(J)在放养后第64天最高,第90天出现差异显著.钩虾的生物量和丰度放养后第30天达到最大值,随后快速下降;蜾蠃蜚的生物量和丰度放养后第14天达到最大值,其丰度在第64天达到第二个高峰.同时,钩虾和蜾蠃蜚群落不同体长个体的丰度百分比差异明显,表现出一定的周期性变化规律.由此,初步分析了引起群落变化的两类原因,提出了钩虾和蜾蠃蜚群落结构的调控方案.  相似文献   

6.
测定了不同时期筼筜湖3种大型底栖动物(沙筛贝Mytilopsis sallei、日本大螯蜚Grandidierella japonica和腺带刺沙蚕Neanthes japonica)及其潜在食源的稳定同位素组成(δ13C和δ15 N),研究环境饵料丰度的季节变化对筼筜湖3种大型底栖动物食性的影响。结果显示,筼筜湖悬浮颗粒有机物(Particulate organic matter∶POM)的δ13C和δ15 N存在明显的季节变化。3月,受到输入筼筜湖的西海域海水大量陆源有机碎屑以及湖区周围的生活污水以及餐饮业输入的影响,筼筜湖POM的δ13 C和δ15 N明显贫化;而在9月,POM中δ13 C和δ15 N明显富集的内源性浮游植物的贡献增加。沙筛贝是典型的底栖滤食者,主要以POM为食,但它比POM富集的δ13 C值(3月和9月二者之间的Δδ13 C分别为2.9‰和1.6‰)表明它还摄入其他δ13 C相对富集的食物来源:石莼来源的有机碎屑可能是3月份沙筛贝δ13C富集的原因,而9月份则是由于再悬浮的底栖微藻对沙筛贝食源的贡献引起的。食碎屑的腺带刺沙蚕和日本大螯蜚在3月以石莼及其表面的附生生物为食,而9月份底栖微藻和浮游植物来源的POM是它们食源的主要贡献者。本研究的结果显示,筼筜湖3种大型底栖动物的δ15 N都出现明显的季节变化(Δδ15 N介于2.2‰~4.3‰),这是由于它们食源稳定同位素的季节性波动及其食性的季节变化引起的,而消费者食性的季节性变化则受到不同时期环境食物可利用性的影响。  相似文献   

7.
青岛潮间带大型底栖海藻群落的研究   总被引:3,自引:0,他引:3  
在青岛潮间带布设了显浪咀、太平角和石老人3个断面,进行了为期1 a(2006年8月~2007年11月)的大型底栖海藻资源调查研究.结果表明:1. 青岛潮间带大型底栖海藻群落的种类组成中红藻种类最多,其次是褐藻,绿藻最少.2. 群落中大型底栖海藻的生物量有明显的季节变化:春季>夏季>秋季>冬季;生物量在垂直分布上表现出中、低潮带均大于高潮带;在水平分布上无明显差异.3. 底栖藻类群落优势种无季节性变化,第一优势种为孔石莼.4. 采集到大型底栖海藻43种,其中红藻门22属24种,占55.8%;褐藻门9属11种,占25.6%;绿藻门6属8种,占18.6%.  相似文献   

8.
本研究基于2013年夏季“大洋一号”船大洋第30航次西南印度洋海区科学考察走航线路,对西南印度洋21°S到38°S海域表层浮游动物群落进行连续采样调查,研究了该海域表层中型浮游动物群落结构和物种多样性及空间分布格局。结果显示,研究海域表层中型浮游动物群落组成包括:桡足类、磷虾类、端足类、十足类、介形类、毛颚动物、被囊类、异足类、翼足类、刺胞动物及多毛类等11大类,总计50属69种;优势类群为桡足类(69%)和磷虾类(27%)。多样性指数随经度和纬度的变化特征:H′、D多样性指数及J均匀度指数随纬度的升高均呈下降趋势;在经度梯度上,几种多样性指数也大致呈现出东高西低的趋势。聚类分析表明,研究区可大致以36°S附近为界划分为南部和北部两大类群,分别以北部桡足类(平均粒径小),南部磷虾类(平均粒径大)Euphausia属为优势群落。群落相似性结果反映出,南部类群与南极克罗克海峡和南极长城湾水域群落,北部类群与西北印度洋海域群落的联通性不高。  相似文献   

9.
关于东海陆架区的浮游端足类??亚目( Amphipoda: Hyperiidea),过去了解很少,迄今仅郑重、郑执中等(1965)报道细长脚?? ( Themisto gracilipes )是黄海主要浮游动物之一。陈瑞祥(1978)报道了采自江苏、浙江近岸水域和福建东南近岸水域数种浮游端足类。 Stephensen(1925)曾报道过Amphithyrus bispinosus分布于香港一上海之间水域。入江春彦(1957)报道了日本五岛列岛一香港之间水域数种浮游端足类。 本文根据1976年调查的资料,对东海大陆浮游端足类??亚目的种类组成和数量分布进行了初步报告。通过这次调查,对调查区的浮游端足类有了初步了解,为今后进一步研究东海浮游端足类的分类与生态工作提供了基本资料。但由于调查时间较短、范围较小,资料仍有一定局限性。  相似文献   

10.
陆源排污对邻近海域底栖海藻群落的影响   总被引:1,自引:0,他引:1  
邵魁双  巩宁  曲翊  李珂 《海洋学报》2019,41(8):106-114
伴随着经济的发展,我国沿海海域富营养化日趋严重。为了明确富营养化对底栖海藻群落的影响及作用机制,本文选择了与大连凌水河口(污水河)毗邻的海藻床作为野外观测点,研究底栖海藻群落对营养盐自然衰减梯度的响应规律;在实验室内,选择了在排污口附近优势分布、营r-生态策略的绿藻缘管浒苔和仅在寡营养区域分布、营k-生态策略的红藻柔质仙菜作为实验材料,开展了营养吸收动力学和生长动力学研究。通过二者在营养盐吸收、利用和繁殖策略方面的比较研究,剖析了底栖海藻群落对不同营养环境的响应机制。结果显示:随着海水中营养盐浓度的降低,底栖海藻群落呈现种类数增加、优势种覆盖度降低的趋势。根据底栖海藻在群落水平对氮源营养的响应,认为现行海水水质标准中无机氮一类水质标准的限值应该由目前的14.29 μmol/L降低为6.69 μmol/L。在富营养环境中,营养盐浓度的上升促进了r-策略海藻幼体的竞争力和种群繁殖力,使其占据了大量的生态位,形成优势种群,导致底栖海藻多样性较低;在寡营养环境中,由于得不到充足的营养盐供应,r-策略海藻幼体的竞争力和种群繁殖力都受到制约,占据的空间生态位有限,为其他种类的生存提供了条件,而那些对营养盐需求较低但利用效率高的k-策略海藻则表现出更强的竞争力,在竞争中取得优势,能快速突破早期环境筛的限制,形成成体,因此,在寡营养海域,底栖海藻的多样性比较丰富。  相似文献   

11.
The Gross growth efficiency(GGE) is defined as the amount of consumer carbon produced relative to the amount of prey ingested in a given time interval. In population ecology, it can be considered as an index for the ability of a consumer to convert the biomass of food into its population production. In this study, it was firstly applied to estimate the role of amphipods grazing in the biomass dynamics of macroalgae(Ulva lactuca) in Yundang Lagoon(a subtropical eutrophic coastal lagoon, Xiamen City, China). It was found that amphipods were the dominant group(82.2%–98.7%) in the benthic assemblage, in which five amphipod species(Corophium uenoi, Ampithoe valida, Grandidierella japonica, Grammaropsis laevipalmata and Caprella panantis) were observed in the lagoon. However, only A. valida significantly consumed U. lactuca among these amphipod species. A series of experiments were conducted to estimate the consumption of U. lactuca by A. valida. It was suggested that the monthly secondary production(P) of A. valida using size frequency method ranged from 2.39 to 13.68 g/m2. GGE of A. valida exponentially reduced with body size and was closely associated with water temperature. Therefore, GGE equation for different months using the temperature recorded during the field investigation was fitted. The monthly consumption of U. lactuca was figured out to be 86.7–1 549.0 g/m2 by the sum of consumption(P/GGE) by A. valida at different size, accounting for 2.0%–37.5% of U. lactuca production. It indicates that the grazing effect of A. valida did play a role in reducing the accumulation of U. lactuca biomass when A. valida was abundant, but it finally fails to limit the U. lactuca growth in Yundang Lagoon. Low abundance of A. valida and high nutrient loading may be two major reasons for the outbreak of U. lactuca bloom in the lagoon.  相似文献   

12.
Year-round investigations were carried out to address the population dynamics of amphipod Ampithoe valida and its potential regulating factors in the Yundang Lagoon (a eutrophic subtropical coastal lagoon in Xiamen City, China) from October 2007 to October 2008. The results show that A. valida population was largely composed of juveniles and reached a peak abundance (12.02 × 10 3 ind./m2 ) in March, but sharply shrunk in July. The monthly variation pattern of A. valida seemed to follow that of Ulva lactuca which is the main food resource for A. valida, indicating a strong influence of food availability on A. valida population dynamics. Life cycle studies in laboratory indicate that A. valida adopted an r-selected life strategy, e.g., rapid growth rate (0.216-0.302 mm/d), consecutive breeding (4-10 times), short reproductive rhythm (9-17 d) and huge fecundity (24-192 eggs or 6-94 juveniles per brood), which contributed to the fast population growth of A. valida from January to March. Although temperature may also be a significant cause, A. valida could grow quickly and show normal reproductive traits (i.e., the timing of sexual differentiation or maturity, the reproductive rhythm, the number of broods all through its lifespan and offspring production) in temperature between 15-30 C. Therefore, the temperature variation in the lagoon water should not account for the sharp variation of A. valida population by affecting the survival, growth and reproduction of the amphipod. However, negative correlation between water temperature and U. lactuca biomass in the lagoon suggested that temperature could have indirectly affected the population dynamics of A. valida by affecting its food availability. The authors conclude that, in the Yundang Lagoon, the population dynamics of A. valida was mainly controlled by the food availability rather than water temperature.  相似文献   

13.
泉州湾污损生物生态研究   总被引:5,自引:4,他引:1  
2001年12月—2002年11月在泉州湾海域进行了污损生物周年挂板试验,共记录污损生物112种,以近岸暖水种为主,其中长鳃麦秆虫(Caprella equilibra)和网纹藤壶(Amphibalanus reticulates)是该海域最具代表性的优势种,其次为裂片石莼(Ulva fasciata)、中胚花筒螅(Tubularia mesembryanthemum)、薮枝螅(Obeliasp.)、纵条矶海葵(Haliplanella luciae)、外伪角涡虫(Pseudoceros exoplatus)、柄涡虫(Stylochus sp.)、僧帽囊牡蛎(Saccostrea cucullata)、翡翠贻贝(Perna viridis)、巴西地钩虾(Podocerus brasiliensis)、强壮板钩虾(Stenothoe valida)、镰形叶钩虾(Jassa falcata)和角突麦秆虫(Caprella scaura)等种类。该海区污损生物全年均可附着,种类丰富且附着强度大,附着盛期在4—11月,月板、季板、半年板和周年板的平均附着生物量分别为2 624g/m2、5 309g/m2、6 210g/m2和8 247g/m2,夏季可达11 295g/m2。随着试板浸海时间的延长,试板上污损生物群落的多样性明显增加,且结构也趋于稳定。  相似文献   

14.
Abstract. Growth of Posidonia oceanica (L.) DELILE was studied in a natural stand in 4 m depth at Ischia (Gulf of Naples). Renewal and growth of leaves was continuous throughout the year but showed strong seasonal modulation. The major factor for individual leaf growth as well as for the seasonal aspects of the entire foliage is seasonal modulation of leaf appearance rather than of leaf growth. Leaf area index varied between 2 nm2 m-2 in autumn and 6 m2 m-2 in late summer. Annual production is estimated to be 613 g dw m-2 for leaf blades, 54 g dw m-2 for leaf sheaths, and 27 g dw m-2 for rhizomes. Rhizome production is highly different between the primary and the secondary growth axis (274 versus 30 mg dw -shoot-1 y-1 respectively) in plagiotrope growth. Both foliage and rhizome growth are positively correlated with leaf width.  相似文献   

15.
In 2002–2008, seasonal (April–November) monitoring of the phytoplankton in the Russian part of the Curonian Lagoon at five fixed sites was performed. A total of 91 Cyanobacteria, 100 Bacillariophyta, 280 Chlorophyta, 21 Cryptophyta, and 24 Dinophyta species were found. Six potentially toxic species of cyanobacteria: Aphanizomenon flos-aquae, Anabaena sp., Microcystis aeruginosa, M. viridis, M. wesenbergii, and Planktothrix agardhii dominated the phytoplankton biomass and caused water blooms. The seasonal average phytoplankton biomass ranged from 30 to 137 g/m3. The cyanobacteria’s biomass varied from 10 to 113 g/m3 forming 30–82% of the total with a mean of 50%. With the aid of genetic markers (microcystin (mcy) and nodularin synthetases), six variants of the microcystin-producing gene mcyE from the genus Microcystis were identified. Due to the intensive and lengthy blooms of potentially toxic and toxigenic cyanobacteria, the environmental conditions in the Curonian Lagoon appear unfavorable. The water should be monitored for cyanotoxins with analytical methods in order to determine if the area is safe for recreational use.  相似文献   

16.
In October and November of 2010, the gelatinous macroplankton in the northwestern Black Sea and at the Crimean shelf was represented by the scyphozoan jellyfish Aurelia aurita, three species of ctenophores (Beroe ovata, Mnemiopsis leidyi, and Pleurobrachia pileus), and three species of hydromedusae. A. aurita was more common at the shelf, M. leidyi and P. pileus prevailed at the deeper sea stations, and B. ovata was almost ubiquitous with a biomass from below 1 to 49 g/m2 A. aurita, which had an average biomass of 82–224 g/m2, was dominant at all the stations. M. leidyi, which had a biomass from below 1 to 115 g/m2, was recorded in October at only 14 of the 52 stations and in November at 20 of the 46 stations. The highest biomass of M. leidyi in October (105 to 116 g/m2) was recorded in the deep sea areas; in November, it was also the highest in these areas, but it reached at most 100 g/m2. The average daily ration of Aurelia ranged from 19.4 to 27.3 mg/m2 in October and from 7.0 to 17.2 mg/m2 in November; in both cases, it was insufficient to provide for the minimal physiological requirements. The average daily ration of the Mnemiopsis population (2.8–20.5 mg of zooplankton per m2) was invariably more than sufficient to provide for the minimal physiological requirements. Both predatory species together consumed less than 5% of the daily zooplankton production of the sea.  相似文献   

17.
We investigated population dynamics, growth and feeding of an omnivorous mysid, Paramysis lacustris, performing seasonal horizontal migrations in the Curonian Lagoon. In autumn, increased predation pressure and deteriorated feeding conditions, due to zooplankton and phytoplankton decline in the open water, forces mysids to migrate to the shoreline, where large amounts of decaying submersed vegetation occur at the end of plant growth season. Using stable isotope analysis and mixing models, we evaluated relative importance of decaying submersed macrophytes, lagoon phytoplankton and mesozooplankton in the diet of mysids during this period. In September–November, mysids actively grew and produced three cohorts. Specific growth rates of adults (10.9 ± 1.9 mm) and subadults (6 ± 0.5 mm) were 3 and 9% DW d−1, respectively, resulting in population somatic production of 36 g DW m−2. Both δ15N and δ13C of mysids varied in concert with those in suspended and bottom particulate organic matter (POM) and mesozooplankton. The mixing models estimated that 45% of mysid diets were composed of bottom POM originated from the decaying macrophyte Potamogeton perfoliatus, 45% by suspended POM largely consisting of phytoplankton, while mesozooplankton contributed less than 10% of the diet. This diet composition differs from that in summer, when mysids rely mostly on zooplankton and phytoplankton. Therefore, mysid horizontal migrations and their ability to efficiently utilize littoral detritus improve the efficiency of macrophyte detritus transfer up the food chain and inshore/offshore habitat coupling in the Curonian Lagoon.  相似文献   

18.
Abstract. .A population of Talorchestia capensis was sampled in dune slacks over the period of one year. Two hatching periods, one in March and one in September, were observed. Growth was rapid, the amphipods reaching a size of 8.4 mm standard length in 18 months. Maximum growth occurred in spring and minimum growth in winter. Annual mortality rates for summer- and winter-hatched individuals were low, 0.22-y“1 and 0.16-y”1. Average production for the summer classes was 7.2g-y?‘ (dry mass) and for the winter classes 2.9-y“1, with a P/B ratio of 2.25-y”’. Production values peaked during autumn and summer. Abundance and biomass estimates showed maxima during summer and minima in early spring. Reproductive output was low, 0.1 kJ ? m-2 y“1, indicating that 7 % of the total production is used for reproduction and 93 % for somatic production. The assimilated energy flow through the population was estimated to be 16.3 kJ m?2 y?‘ and consumption about 81.6 kJ m-2 y_’.  相似文献   

19.
Data are presented on biomass, mortality, growth, and production of fish populations inhabiting two small streams in the Wairarapa district of the North Island of New Zealand. The main water of both streams contained a mixed population of bullies (Philypnodon breviceps Stokell), brown trout (Salmo trutta Linn.), and eels (Anguilla dieffenbachii Gray, and A. australis schmidtii Phillipps). The headwater tributaries of one of the streams contained a large population of Galaxias divergens Stokell and a few eels, but other fish species were absent. All species of fish appeared to be using the same food supply of small benthic invertebrates, mainly ephemeropteran and dipteran larvae. Biomass of benthos per unit area was appreciably higher in the headwater tributary examined than in the main waters downstream. Mean annual stock of benthos in the tributary (Hinau north branch) was 19.75 g/m2, in the Hinau main water 10.71 g/m2 and in the Hinaki main water 13.47 g/m2 Nevertheless, production per unit area from the nearly monospecific fish population in the Hinau north branch (14.28 g/m2) was less than that of the mixed populations in the main waters (24.17 g/m2 in the Hinau, 73.54 g/m2 in the Hinaki). Possibly fish production in the headwaters might be greater if the species composition of fish was more diverse.  相似文献   

20.
Abstract. The secondary production and population dynamics of the mole crab Emerita brasiliensis Schmitt, 1935 (Decapoda: Hippidae) were studied by taking monthly samples from June 1993 to May 1995 at each of three intertidal transects at Prainha beach, Brazil. The lifespan was ca. 8 months for males and females, but females showed higher growth, mortality, secondary production, and turnover rate. The higher production in spring versus autumn and winter was related to intense recruitment during that period. The population production was estimated at between 39.86 and 46.88 g (AFDW) · m?2 · a?1 for the first year (June 93–May 94) and between 150.95 and 156.07 g (AFDW) · m?2 · a?1 for the second year (June 94–May 95); the mean annual biomass was 4.91 and 23.09 g (AFDW) · m?2, respectively. High P/B rates, between ca. 6 and 9 · a?1, reflected the fast growth, high mortality, and low lifespan of the population, characterized by a high percentage of recently recruited individuals.  相似文献   

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