首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 23 毫秒
1.
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       下载免费PDF全文
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   

2.
根据珠江口枯水期(2013年11月)和丰水期(2014年8月) 24个站位调查资料,对中小型浮游动物种类组成、丰度分布、群落结构及其主要影响因子进行了研究.结果表明,枯水期和丰水期分别鉴定浮游动物成体91种和70种,以桡足类最为丰富.浮游动物种类从河口上游向外围逐渐增加.浮游动物丰度时空分布差异显著,丰水期平均值高达11 619. 78 ind/m~3,显著高于枯水期的1 707. 13 ind/m~3.桡足类在珠江口中小型浮游动物中占绝对优势,枯水期和丰水期分别占总丰度的80. 3%和93. 0%,对浮游动物的丰度分布起关键作用.强额孔雀哲水蚤(Parvocalanus crassirostris)、中华异水蚤(Acartiella sinensis)和刺尾纺锤水蚤(Acartia spinicauda)在两个水期均为主要优势种,小拟哲水蚤(Paracalanus parvus)和厦门矮隆哲水蚤(Bestiolina amoyensis)则分别在枯水期和丰水期具有较高的优势度.聚类分析的结果显示,枯水期和丰水期该水域浮游动物均可划分为3个群落.相关性分析表明,珠江口中小型浮游动物群落结构受多个环境因子的影响,但盐度是其中最为关键的非生物因子.  相似文献   

3.
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   

4.
The habitat characteristics and spatial segregation of the two common gobies Gobius fallax Sarato, 1889 and Gobius auratus Risso, 1810 were investigated by fish frequency and abundance estimates through visual counts in the northern Adriatic Sea. The latter species is represented by a recently described, unusual colour morph in the northern Adriatic Sea. Gobius fallax was observed at five of the nine locations examined and its abundance did not differ between two of three transect locations at Piran (Slovenia) and at the western coast of Cres (Kvarner region, Croatia). Gobius auratus was not found in the Gulf of Trieste but was present at several Kvarner locations, and co‐occurred with G. fallax at one location at Cres. Both inhabit rocky substrates but they show different preferences for substrate inclinations and bathymetric segregation. Gobius fallax was most frequent between 2 and 8 m depth and was most abundant on substrate inclining less than 30°. Its highest abundance over entire transects was 0.3 indiv.·m?2 but within certain transect sections this increased to 1.25 indiv.·m?2. Gobius auratus attained its highest abundance in depths below 8 m and at substrate inclinations between 30 and 90°. This species attained its highest values at the western coast of Cres, where it reached a maximum of 1.5 indiv.·m?2 over entire transects but even up to 3.0 indiv.·m?2 in certain transect sections. At Krk, the maximum abundance over entire transects was only 0.3 indiv.·m?2.  相似文献   

5.
根据2017年10月和2018年1、5、7月对雷州半岛沿岸海域浮游动物四个季度的调查数据,分析了浮游桡足类群落组成的季节变化及其影响因素.结果共鉴定出浮游桡足类80种,其中哲水蚤目55种,占总种类数的68.7%;剑水蚤目21种,占总种类数的26.2%;猛水蚤目3种,占总种类数的3.8%;鱼虱目1种,占总种类数的1.3%...  相似文献   

6.
The species composition, density, biomass, and distribution of zooplankton of the northeastern Sakhalin shelf, Sea of Okhotsk (Chaivo, Pil’tunskii, and Morskoi regions) were studied in October 2014. Zooplankton was represented by 15 taxonomic groups, which were dominated by Copepoda (13 species). The average density and biomass was highest in the Chaivo region (14112 ± 4322 ind./m3, 395 ± 107 mg/m3) and in the Pil’tunskii region (16692 ± 10707 ind./m3, 346 ± 233 mg/m3); the abundance of detected taxonomic groups was minimal (8–12). The average density and biomass of zooplankton was up to 4304 ± 2441 ind./m3, 133 ± 77 mg/m3 in the Morskoi region and increased with depth; the abundance of taxa was maximum (15). Four species of copepods made up the majority of the density and biomass of zooplankton: Acartia hudsonica, Eurytemora herdmani, Pseudocalanus newmani, and Oithona similis. In the Chaivo region, species of the genera Acartia, Eurytemora, and Oithona dominated and subdominated; in Pil’tunskii region, species of the genera Acartia and Oithona dominated and subdominated; and in the Morskoi region, species of the genera Oithona, Pseudocalanus, and Acartia dominated and subdominated.  相似文献   

7.
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   

8.
在2011年丰水期(7月)和2012年枯水期(3月),分别对钦州湾的内湾和外湾开展了浮游动物调查,研究了枯水期和丰水期钦州湾浮游动物的种类组成、数量分布和季节变化特征。丰水期和枯水期浮游动物种类数量分别为27种和44种,以优势度指数Y0.02确定的优势种丰水期和枯水期分别为3种和4种。丰水期浮游动物丰度为4.0~133.6ind/m3,平均丰度为50.9ind/m3;枯水期浮游动物丰度为1.2~1 725.0ind/m3,平均丰度为272.2ind/m3。丰水期浮游动物(包含鱼卵仔鱼)生物量为1.7~179.2mg/m3,平均生物量为44.0mg/m3;枯水期浮游动物(包含鱼卵仔鱼)生物量为3.1~3 530.0mg/m3,平均生物量为474.9mg/m3。无论是浮游动物的种类数量、丰度和生物量,均显示出内湾低于外湾的空间分布特征,以及枯水期高于丰水期的变化特征。钦州湾浮游动物的这种季节变化和空间分布特征主要是与浮游植物生物量、贝类养殖、环境的稳定度以及人为干扰等有着密切的关系。  相似文献   

9.
于2009年4月15~23日在长江口及其邻近海域进行了32个站位的浮游动物生态调查,分析了浮游动物的种类组成、优势种、丰度和生物量的空间分布,并利用PRIMER生物统计学软件中的PCA、BIOENV和RELATE程序分析了浮游动物与环境因子的关系.共发现浮游动物成体72种,浮游幼虫9种,合计种类数为81.中华哲水蚤(C...  相似文献   

10.
Abstract The annual variability in abundance and biomass of Flaccisagitta enflata (Grassi, 1881) and Mesosagitta minima (Grassi, 1881), along with the C‐ and N‐content of their different maturity stages, were investigated in the South Adriatic Sea on a weekly basis throughout 1996. Increases in abundance and biomass of F. enflata [maximum 554 indiv. · (10 m3)–1 and 16.3 mg C · (10 m3)–1] and M. minima [maximum 336 indiv. · (10 m3)–1 and 3.1 mg C · (10 m3)–1] were found in summer and autumn, a time of intense reproduction for these species. Mean carbon content (as a percentage of dry weight) varied from 30.41 to 40.39 % among maturity stages for F. enflata, and from 27.73 to 39.31 % for M. minima. Nitrogen contents of both species were ~ 3 to 3.5 times less than carbon contents and varied less. Accurate estimates of chaetognath biomass as carbon should be based on the separate contribution of each maturity stage present in the total population.  相似文献   

11.
浮游动物死体是海洋沉降碳通量的重要组成部分,研究浮游动物死体对于准确评估特定海区生物泵碳通量具有十分重要的意义。为了解夏季南黄海浮游甲壳动物在自然海区的死亡情况,采用2019年7~8月在南黄海获取的浮游动物样品,使用中性红染色法分析了浮游甲壳动物死体的平面分布及其受控环境因素。结果表明,夏季南黄海浮游甲壳动物平均丰度为(1 378.3±929.84) ind./m3,其死体比例在5.0%~68.8%之间,平均为33.3%±16.6%。桡足类是浮游甲壳动物的主要类群,平均丰度为(1 202.9±937.4) ind./m3,死体比例在3.6%~69.7%之间,平均为38.6%±17.0%,与全球海域浮游桡足类的平均死体比例相当。不同浮游甲壳动物优势种的死体比例存在差异。其中,拟长腹剑水蚤(Oithona similis)死体比例最高(62.0%),鸟喙尖头溞(Penilia avirostris)最低(17.9%)。与环境因子的相关性分析结果表明,海水温度和盐度是影响夏季南黄海浮游甲壳动物死体比例的主要影响因子。小拟哲水蚤(Paracalanus parvus)死体比例和表层温度显著正相关,拟长腹剑水蚤和近缘大眼剑水蚤(Corycaeus affinis)的死体比例与表底温差具有显著的正相关;而表层盐度与克氏纺锤水蚤(Acartia clausi)的死体比例存在正相关关系。该研究结果可为深入认识南黄海海洋生态动力学过程和海洋碳通量等相关研究提供重要的参考资料。  相似文献   

12.
Water moved into the creekbank sediments in direct response to the changing levels of the water table caused by the tides. The net water loss of the sediments was 3–30% on each low tide and this loss was confined to within 4 m (horizontal) of the creek. The replacement of this water by incoming tidal water could not supply sufficient nutrients for the growth of creekbank Spartina. However, during ebb tide there was a replacement of water in the creekbanks with nutrient-rich water from the marsh interior as demonstrated by the large changes in pore water chemistry over a tidal cycle. The concentration and the range of a chemical parameter depended upon the stage of the tide, the tidal range, the time of year and (for salinity) the rainfall patterns of the month preceding sampling. Over a single tidal cycle the maximum ranges were: salinity ‰, 26–33; alkalinity, 2·5–13·6 med 1?1, ammonia, 2–400 μm, sulfate, 23·5–29 mmol 1?1. Measurable concentrations of sulfide were only found in a few samples. This high nutrient water can supply nitrogen and probably other nutrients to Spartina.  相似文献   

13.
This study describes the spatial and temporal dynamics of the copepod fauna in the estuary of the Caeté River, a highly dynamic environment characterized by a unique set of hydrological and hydrodynamic attributes. This ecosystem is part of the Amazon Coastal Zone (ACZ), which sustains one of the world's largest continuous tracts of mangrove forest. In the present study, a predominance of high‐energy conditions characterized by macrotides and strong tidal currents was observed throughout the year. Salinity (0.03 ± 0.05–40.00 ± 0.84) and temperatures (26.43 ± 0.10–30.08 ± 0.43 °C) were higher than during the rainy season at all sampling stations. The highest chl‐a concentration (3.92 ± 1.47–17.63 ± 2.60 mg·m?3) was recorded at the most oligohaline (innermost) station during the rainy season, while no spatial or seasonal pattern was found in dissolved nutrient concentrations, except for phosphates, which exhibited the highest concentrations during the dry season. A total of 22 copepod taxa was identified, of which the most abundant were Oithona hebes, Oithona oswaldocruzi, Acartia tonsa, Paracalanus quasimodo, Euterpina acutifrons and Pseudodiaptomus marshi. Copepodites and nauplii were also recorded. Mean total copepod abundance varied from 710.73 ± 897 individuals (ind.)·m?3 at the inner station to 236,486 ± 398,360 ind.·m?3 near the mouth of the estuary (outermost station). The results reflected rainfall‐influenced oscillations in hydrological variables, mainly salinity, which determined shifts in the distribution of copepods and their community structure within the study area. This pattern may be typical of estuaries in the ACZ with similar hydrodynamic and hydrological attributes that are not influenced by the Amazon River plume.  相似文献   

14.
Abstract. The nematode fauna of the phytal region of a stand of the Mediterranean seagrass Posidonia oceanica (L.) Delile was studied in a shallow subtidal location (5 m) at the island of Ischia (Gulf of Naples, Italy). During a one year's growth-cycle of the seagrass, abundance and faunal composition of the nematode community were investigated in a stratified sampling survey. Ninety seven species of nematodes were found. Nematode density and biomass ranged from 1.3 · 105 indiv. · m-2 (0.02g dwt · m-2) in winter to 5.5 · 105 indiv. · m-2 (0.08 g dwt · m-2) in early autumn. Density and biomass of nematodes were much lower and showed more marked seasonal fluctuations in the leaf strata than in the stem stratum of the seagrass. Diversity and seasonal homogeneity (expressed with Riedl 's index) were much lower in the two leaf strata (25–36 species, 29.6 ho%) than in the stem stratum (60–70 species, 42.5 ho%). The nematode community of the leaf stratum can be characterized as a Chromadora nudicapitata – Monhystrella sp. –Symplocostoma tenuicolle– community and is clearly set off from the stem stratum community (9.2% Riedl 's ho%), which is characterized as a Molgolaimus sp. 1 –Epsilonema sp. 1 –Chromadora nudicapitata– community. In the seasonal succession, the leaf stratum fauna shifts from a chromadorid-dominated community (from winter to summer) to a monhysterid-dominated community in early autumn. The stem stratum fauna shifts from a epsilonematid-dominated fauna in winter to a molgolaimid-dominated fauna in summer and early autumn. The distribution of nematode size classes showed a clear selection toward small animals (< 1 mm lenght), although marked seasonal fluctuations in size class distribution were observed. A modified approach for describing the trophic structure of the nematode fauna is presented. The observed abundance patterns and changes of community composition are discussed in relation to the development of habitat complexity and in relation to trophic conditions in the scagrass stand according to the seasonal growth rhythm of the plants and their aufwuchs-community.  相似文献   

15.
2001—2002年粤东柘林湾浮游动物的生态学研究   总被引:25,自引:3,他引:25  
2001年4月-2002年4月,利用生态学方法对粤东柘林湾浮游动物进行的周年调查结果表明,粤东柘林湾浮游动物有桡足类34属60种,枝角类3属3种,及端足类、磷虾、糠虾、多毛类、毛颚类、被囊类、水母和各种浮游幼体虫.浮游动物的群落构成小型化趋势明显,因为体长不足0.6 mm的小型优势种强额拟哲水蚤(Paracalanus crassirostris)、短角长腹剑水蚤(Oithona brevicornis)和鸟喙尖头(氵蚤)(Penilia avirostris)在浮游动物总个体数中所占比例合计高达57.1 %.浮游动物的种类数、总个体数和生物量的平面分布模式大体相似,即湾外大于湾内,外侧大于内侧,东部大于西部.总个体数与生物量的周年变化曲线与水温的变化趋势非常相似,高峰位于高温季节的8-9月,低谷位于冬季2月.调查期间柘林湾浮游动物非常丰富,年均总个体数达15.8×103 ind/m3,生物量达227.8mg*dW/m3.在单一调查年度内,浮游动物丰度与水温、浮游植物细胞数呈显著正相关关系.在不同年份,浮游动物丰度与浮游植物密度则表现为负相关的趋势.  相似文献   

16.
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   

17.
Abstract. The present study analyzes the distribution, population structure, population biomass and morphological characteristics of the intertidal tunicate Pyura stolonifera (Heller, 1878) in the Bay of Antofagasta, Chile, where the species shows a reduced geographical range extending around 60 – 70 km. Three sites along its distribution were studied. At the central site the tunicate presents the widest intertidal belts, reaching nearly 11 m (the mid‐intertidal‐Pyura‐zone shows the higher percent cover). Population dry biomass here averaged up to 20.45 kg·m–2, representing one of the highest intertidal specific biomasses reported in the literature. Lower values occur towards the borders of its distribution. Population densities were over 1800 indiv.·m–2 at mid‐intertidal‐Pyura‐belts. Crowding and competition potentially affect morphological characteristics and the energy/tissue allocation along the intertidal and geographical gradient of P. stolonifera.  相似文献   

18.
印度尼西亚北苏拉威西蓝碧海峡浮游动物种类组成及分布   总被引:1,自引:0,他引:1  
Based on oceanographic survey data in June 2012 in the Lembeh Strait, the zooplankton ecological characteristics such as species composition, individual abundance, dominant species and distribution were analyzed. The results showed that 183 species(including 4 sp.) had been recognized, most of them belonged to copepoda.Cnidaria followed with 43 species(including 1 sp.) were identified. The average abundance of zooplankton was(150.47±58.91) ind./m~3. As to the horizontal distribution, the abundance of the zooplankton was higher in the southern waters than in the northern waters. The dominant species in the study area were Lensia subtiloides,Sagitta enflata, Lucifer intermedius, Oikopleura rufescens, Diphyes chamissoni, Creseis acicula, Subeucalanus subcrassus, Temora discaudata, Aglaura hemistoma, Doliolum denticulatum, Canthocalanus pauper, Oikopleura longicauda and Nanomia bijuga. Zooplankton biodiversity indexes were higher in study area than previous study in the other regions. The findings from this study provide important baseline information for future research and monitoring programs.  相似文献   

19.
2012年冬季菲律宾海浮游动物丰度和生物量的水平分布   总被引:1,自引:1,他引:0  
为了解西太平洋菲律宾海浮游动物丰度和生物量的水平分布特征,于2012年11月26日至2012年12月12日对菲律宾海上层海洋(0—200m)的浮游动物进行了调查。调查站位分别位于受赤道逆流(NECC)、棉兰老流(MC)、北赤道流(NEC)和黑潮(KC)影响的海域。通过比较浮游动物的丰度和生物量(分别用干重,灰分,无灰干重和含能量等指标表示),探讨不同海流中浮游动物的分布特征。结果表明:桡足类、毛颚类和水母类是菲律宾海浮游动物的三大主要类群。调查海域浮游动物丰度为11—116ind./m3,NECC区平均丰度最高((96±28)ind./m3),然后依次是MC区和KC区,NEC区最小((26±9)ind./m3)。在浮游动物生物量(干重)方面,同样NECC区最高((3.25±1.11)mg/m3),其次为MC区,但是平均丰度最小的NEC区生物量超过KC区。造成这一差异的主要原因,可能是由于KC区的浮游动物具有更高的含水量以及较小个体所占比例较高。不同水团之间浮游动物灰分、无灰干重和含能量的分布特征与干重相一致。结合环境因子分析显示,上升流、叶绿素a、初级生产力、海流和温度等因素对浮游动物的分布具有一定影响。  相似文献   

20.
The effect of environmental factors (river discharge, water temperature and dissolved oxygen saturation) on the abundance and distribution of Acartia populations and the interactions between their congenerics was evaluated by means of transfer function (TF) models in the estuary of Bilbao during the period 1998–2005. The recorded species were Acartia clausi, Acartia tonsa, Acartia margalefi and Acartia discaudata. Acartia clausi dominated in the entire euhaline region of this estuary until 2003 when it was displaced from the inner part by A. tonsa. This invasive species (A. tonsa) was found for the first time in 2001 and colonized successfully the inner (salinity 30) and intermediate (salinity 33) waters of this estuary since 2003. The TF models revealed an immediate and negative effect of A. tonsa on A. clausi in the intermediate salinity (33) waters, where these species showed the highest spatial overlap. The results indicate that environmental changes from 2003 influenced the abundance of Acartia species, being unfavourable for A. clausi. The decrease of A. clausi abundance in low salinity waters was related to a significant decrease of dissolved oxygen saturation levels, whereas the increase of temperature was linked to a significant increase of A. tonsa. Acartia margalefi and A. discaudata were scarce over the entire period, but they were found to be valuable indicators of hydrological changes, which were associated to climate factors. These two latter species increased in abundance and expanded their seasonal distribution, and in the case of A. margalefi also its spatial distribution, in 2002, coinciding with the period in the time-series when autumn–winter rainfall and summer temperatures were lowest, and dissolved oxygen saturation levels were highest.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号