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1.
应用濒海陆基水池中8个围隔生冬系实验袋研究污染物对浮游动物的影响,结果表明:低浓度Cd,Cu,Pb,Zn,Hg的混合物对草食性桡足类的生长发育有一定的抑制作用,当浓度增到高值,抑制作用更为强烈.低浓度沉积物对草食性桡足类的生长发育同样具有一定的抑制作用,当浓度增到高值,抑制作用也更为明显,两类污染物均在不同程度上改变了生态系的结构,肉食性桡足类对污染物的反应并不明显,但幼形类住囊虫(Oikipleura sp.)对低,高浓度混合重金属则较为敏感,而对低、高浓度的沉积物却没有表现出明显的反应迹象. 相似文献
2.
不同饵料对桡足类无节幼体存活、发育的影响研究 总被引：5，自引：0，他引：5
在食物中碳质量浓度为1.0 mg/L的条件下,通过室内实验研究了不同食物对中华哲水蚤(Calanus sinicus)和双刺纺锤水蚤(Acartia bifilosa)无节幼体存活和发育的影响。结果表明,桡足类无节幼体发育速度与存活率之间存在正相关关系。单种食物中粒径较小的微绿球藻和三角褐指藻在桡足类开口摄食期是最适宜的饵料,但在发育后期以及整个发育期则粒径较大的亚心型扁藻和中肋骨条藻更为适宜。在相同的发育阶段,小型桡足类双刺纺锤水蚤和中型桡足类中华哲水蚤对于食物粒径的选择也是不同的。与非硅藻食物相比,硅藻并非桡足类无节幼体发育的理想食物,而单种硅藻对桡足类无节幼体发育的负面影响可以通过对混合食物的摄食得到有效的减弱。 相似文献
3.
罗非鱼放养量对盐碱水微型生态系统浮游生物群落的影响 总被引：2，自引：0，他引：2
报道了放养不同密度的尼罗罗非鱼 (orecohromis niloticus)对微型生态系统浮游生物影响的研究结果。罗非鱼的放养量为 5个水平 (0～ 8.12 kg· m-3 )。结果表明 ,随着罗非鱼放养量的增大 ,蓝藻、金藻、轮虫、枝角类、桡足类的量、p H、和 TN:TP比值下降 ;相反 ,绿藻、硅藻、原生动物、浮游植物叶绿素 a含量、浊度、总碱度、电导率、TN和 TP均增加 ;而在生物量上小型硅藻和绿藻占优势使浮游植物小型化。 相似文献
4.
5.
瘦尾胸刺水蚤摄食率的观察实验 总被引：1，自引：0，他引：1
厦门港浮游桡足类瘦尾胸刺水蚤(Centropages tenuiremis Thompson ＆ Scott)成体的摄食率受到食物浓度、容器的容积和温度的显著影响,而试验动物密度和昼夜周期的影响不显著。文中还对瘦尾胸刺水蚤的选择摄食机制作了初步的探讨。 相似文献
6.
对虾池混养滤食性动物对浮游生物的影响 总被引：3，自引：0，他引：3
于１９９７年５～８月在山东海阳养虾场运用陆基围隔实验生态学方法,研究了罗非鱼—对虾、海湾扇贝—对虾、缢蛏—对虾、罗非鱼—缢蛏—对虾４种混养系统中滤食性动物对浮游生物群落的影响。结果表明：滤食性动物的滤食作用降低了浮游植物生物量和甲藻在浮游植物中的比例;混养罗非鱼和扇贝使浮游植物群落的多样性增加,而混养缢蛏却使它下降;罗非鱼优先滤食大型桡足类,使小型浮游动物增加,从而提高了浮游动物的总生物量,而扇贝则优先滤食浮游动物的小型种类;由于罗非鱼和缢蛏生态灶的互补性,罗非鱼—缢蛏—对虾混养能更全面、有效地利用浮游生物资源,促进生态平稳 相似文献
7.
利用现场海水培养实验,结合浮游动物网样数据,研究长江口邻近海域几种优势桡足类(中华哲水蚤、背针胸刺水蚤、太平洋纺锤水蚤和精致真刺水蚤)对微型浮游动物的摄食影响。结果表明,精致真刺水蚤虽然属于肉食性种类,但几乎不摄食微型浮游动物;其余三种杂食性桡足类中华哲水蚤、背针胸刺水蚤和太平洋纺锤水蚤对微型浮游动物(纤毛虫+异养甲藻)的摄食率分别为0.66、0.09和0.59μg C/(ind·d),分别占其日总摄食量的29%、24%和37%。其中,异养甲藻在初始生物量和对桡足类饵料贡献上分别占整个微型浮游动物的30%和28%,是微型浮游动物中一个重要的组成类群。中华哲水蚤对微型浮游动物的摄食率与初始食物浓度有显著的正相关关系,并且对体长20μm纤毛虫的清滤率要明显高于对体长20μm的纤毛虫(P0.01)的清滤率,表明其偏好摄食较大个体的食物。通过Chesson选择性指数显示,尽管微型浮游动物在生物量上远小于浮游植物,但桡足类能优先选择摄食微型浮游动物;进一步结合网采浮游动物数据,获得各站三种优势桡足类丰度平均占桡足类总丰度的77%,但它们对微型浮游动物现存生物量的摄食压力仅为0.8%,表明桡足类对微型浮游动物群落的下行控制作用并不明显,仍有大部分微型浮游动物生物量未通过摄食途径进入到桡足类群落中。 相似文献
8.
可溶性Fe对中尺度海洋围隔生态系中浮游生物群落数量变动的影响 总被引：1，自引：0，他引：1
作者首次应用3个中尺度海洋实验生态系围隔装置研究可溶性Fe 对浮游生物群落数量变动的影响。结果表明:添加10和50μg/dm~3的可溶性Fe,均大大促进了浮游植物,特别是硅藻类中中肋骨条藻(Skeletonema costatum)的生长。但浮游植物的过量繁殖并没有导致生态系中滤食性桡足类数量的增加。 相似文献
9.
2005年6月至2006年3月对湄洲湾北岸灵川贝类养殖滩涂的小型底栖动物进行研究,并探讨了贝类养殖对滩涂底栖环境可能造成的影响.结果表明:小型底栖动物的总平均密度为65.7±37.5个/cm2,春季(3月)的密度比其它季节高.线虫和桡足类是小型底栖动物密度的主要组成,其中线虫平均密度为63.9个/cm2,约占密度组成的97.3%;桡足类平均密度为0.77个/cm2,约占密度组成的1.2%.许多站次的线虫和桡足类数量之比(N/C)均超过100,多贝类养殖的Y断面的小型底栖动物密度、N/C均比寡贝类养殖的F断面高. 相似文献
10.
黄河口邻近水域中华哲水蚤现场食物组成的分子生物学检测 总被引：1，自引：0，他引：1
浮游桡足类是海洋初级生产力和高级营养级之间能量传递的重要中介,对自然海区桡足类食物组成的研究是深入了解其在海洋食物网所处生态地位的关键。然而,由于研究方法的局限,目前很难获取桡足类准确的现场摄食信息。本文用分子生物学方法研究了黄河口邻近水域中华哲水蚤的现场食物组成,对现场采集固定的中华哲水蚤样品进行清洗、去除附肢、镜检等处理,研磨匀浆后提取总基因组DNA。基于对以此DNA为模板扩增出的非桡足类核糖体小亚基基因(non-copepod 18SrDNA)序列的分析,本文共检测出属于8个门的中华哲水蚤的潜在食物种类。研究结果表明,PCR的分子生物学技术在桡足类摄食研究中具有强大的效用,同时,诸多潜在食物类群的发现也意味着利用分子生物学方法对桡足类及其它海洋生物现场食物组成进行深入系统研究,将有利于揭示海洋生态系统结构与功能的真实状态,促进海洋生态系统物质循环和能量流动的研究。 相似文献
11.
基于能值理论,结合生态足迹方法,构建能值生态赤字/盈余、渔业足迹强度(D)、社会发展压力指数(I)和经济协调指数(Q)参数评价海岛可持续性,选取典型海岛城市浙江省舟山市作为案例研究。结果显示:2003—2017年舟山能值足迹、能值承载力均呈上升趋势;人均能值生态足迹共增加15.78 hm2,增幅为63.26%;人均能值承载力增加5.20×102 hm2,增幅为82.86%;其中,化石能源用地能值足迹增加最多,社会经济承载力增加最多,而自然承载力却有所下降。能值生态赤字/盈余和经济协调指数不能完全反映区域可持续性,区域渔业足迹强度的不断增加表明当前的渔业经济模式不满足可持续发展要求,社会发展压力指数增大也进一步表明舟山的发展状况偏离了可持续性的轨道。 相似文献
12.
小型桡足类在海洋生态系统中的功能作用 总被引：32，自引：10，他引：32
依据渤海周年的中型浮游动物网样品 ,研究了小型桡足类的优势种小拟哲水蚤(Paracalanusparvus)、强额拟哲水蚤 (Paracalanuscrassirostris)和双刺纺锤水蚤 (Acartiabifilosa)生物量的季节变动、分布和年产量 ,并与渤海大型桡足类的优势种中华哲水蚤 (Calanussinicus)进行了比较。结果表明 ,三种小型桡足类成体的年产量分别为 2 4 .89、1 0 .83和 1 9.5 4mgC/(m3·a) ,中华哲水蚤的年产量为 1 8.30mgC/(m3·a)。小型桡足类主要分布在近岸 ,特别是渤海湾和莱州湾 ,这里正好是许多经济鱼类的产卵场和育幼场 ;而中华哲水蚤主要分布在中央水域。小型桡足类的高峰季节持续时间长 ,从 4月到 1 0月 ,覆盖了几乎所有仔稚鱼大量出现的月份 ;而中华哲水蚤高峰季节持续时间短 ,仅 6月和 7月。另外 ,在粒度上 ,小型桡足类的卵、无节幼体、桡足幼体和成体都比中华哲水蚤等大型桡足类小了一个数量级 (按体积计 ) ,特别适合作为仔稚鱼的饵料。因此认为 ,在近海生态系统中 ,小型桡足类较之大型桡足类起更为重要的作用 相似文献
13.
Impacts of CO2-driven seawater acidification on survival, egg production rate and hatching success of four marine copepods 总被引：1，自引：0，他引：1
Ecological experiments were conducted to examine the effects of seawater containing elevated par- tial pressure of carbon dioxide (p CO2 800 × 10 -6 , 2 000 × 10 -6 , 5 000 × 10 -6 and 10 000 × 10 -6 ) on the survival and reproduction of female Acartia pacifica, Acartia spinicauda, Calanus sinicus and Centropages tenuiremis, which are the dominant copepods in the southern coastal waters of China. The results show that the effects of elevated p CO2 on the survival rates of copepods were species-specific. C. sinicus, which was a macro-copepod, had a higher survival rate (62.01%-71.96%) than the other three species (5.00%-26.67%) during the eight day exposure. The egg production rates of C. sinicus, A. spinicauda and C. tenuiremis were significantly inhibited by the increased p CO2 and the exposure time duration. There were significantly negative impacts on the egg hatching success of A. spinicauda and C. tenuiremis in the p CO2 2 000 × 10 -6 and 10 000 × 10 -6 groups, and, in addition, the exposure time had noticeably impacts on these rates too. This study indicates that the reproductive performances of copepods were sensitive to elevated p CO2 , and that the response of different copepod species to acidified seawater was different. Furthermore, the synergistic effects of seawater acidification and climate change or other pollutant stresses on organisms should be given more attention. 相似文献
14.
海草床是三大典型的近海海洋生态系统之一,具有极高的生态服务功能。然而,截至2015年我国近海海草资源分布现状尚不明晰,严重制约了我国海草床保护与修复工作的开展。2015～2021年,笔者通过实地调查,借助船只走航、声呐探测、遥感等技术手段,重点对我国近海海草资源的分布面积、种类及主要威胁进行了全面普查,并据此提出我国海草床管理与可持续利用对策。结果表明,我国近海海域海草床面积共为26 495.69hm2,可划分为:温带海域海草分布区和热带-亚热带海域海草分布区;我国现有海草4科9属16种。其中,温带海域海草床面积为17 095.01 hm2,主要分布在辽宁、河北、天津和山东沿海,分布有2科3属5种,以鳗草(Zosteramarina)和日本鳗草(Z.japonica)为优势种,其中唐山乐亭-曹妃甸海草床面积达9 025.56 hm2,是我国面积最大的海草床;热带-亚热带海域海草床面积为9 400.68 hm2,主要分布在福建、广东、广西和海南沿海,分布有4科8属12种,以泰来草(Thalassia hemprichii)、海菖蒲(Enhalus acoroides... 相似文献
15.
Parameters of community structure (species composition and relative abundance, number of taxa, diversity, evenness, and cell density) were measured for a mudflat diatom community in the Avon‐Heathcote estuary, New Zealand. Fifty three diatom species were identified: 25 taxa (species and varieties) are new New Zealand records. The Shannon‐Wiener information index (H') was 3.46, indicating high diversity. Evenness (J') ranged from 0.57–0.67. The association between the biomass of the pulmonate gastropod, Amphibola crenata, and benthic diatom community structure was studied using large open enclosures (4.0 m2) to manipulate snail biomass. Community structure was compared at 0, 5 (natural biomass), and 10 g A. crenata dry weight per m. A similarity index (SIMI=0.88–0.95), as well as H’ and J’ indicated close similarity between the diatom assemblages within all enclosures, but number of taxa increased from 33 to 49 with increasing snail biomass. Cell densities were significantly lower at high snail biomass (6088 valves per mm2) compared to enclosures with no snails (10 110 valves per mm ). A. crenata had a higher ratio of diatom fragments to whole diatom valves in its faeces (2.42) than in its crop (0.55), indicating that it is capable of fragmenting diatoms. 相似文献
16.
Jefferson T. Turner Russell R. Hopcroft Jean A. Lincoln Cameran Sassman Huestis Patricia A. Tester John c. Roff 《Marine Ecology》1998,19(3):195-208
Abstract. Grazing by the copepods Temora turbinata and Acartia lilljeborgii and the marine cladoceran Penilia avirostris on natural phytoplankton and cyanobacteria assemblages from Kingston Harbour. Jamaica, was examined in summer 1992. Food assemblages were often dominated by an unidentified filamentous cyanobacterium. with abundances of up to 1.16 × 104 filaments. ml-1. Other abundant phytoplankters included microflagellates and diatoms of the genus Niteschia. Mean clearance rates for the entire food assemblage ranged from 0.10 to 2.41 ml animal-1. h-1, although most mean clearance rates were between 0.5 and 1.5 ml. animal-1 h-1. Patterns of selection of different food items by various grazers on different dates were variable and inconsistent. Microscopic measurements revealed that cyanobacterial filament lengths were shorter in grazed than initial aliquots during a cyanobacterium bloom in August. This suggests that grazers reduced lengths of many filaments by biting off portions, in addition to consuming entire filaments. Such ‘filament clipping’ of cyanobacteria filaments has been recorded previously in freshwater studies and suggests that grazers impact a larger portion of the phytoplankton assemblage than is accounted for by ingestion and clearance rates based only upon removal of filaments. Grazers exhibited no adverse effects from consuming cyanobacteria. Cyanobacterkd are often considered to be toxic or of poor food quality for planktonic grazers. but due to the high abundance and dominance of filamentous cyanobacteria in Kingston Harbour. if these cyanobacteria were ungrazed. there would at times be little alternative phytoplankton food for copepods and cladocerans. Our results suggest that the trophic role of tilamentous cyanobacteria in pelagic food webs of the tropical ocean should be further investigated and possibly reconsidered. 相似文献
17.
Food differentiation among coexistent species in the field is important strategy for copepods to acquire materials and maintain population stabilization.In situ diet analysis of co-occurring six copepod species in coral waters of the Sanya Bay was conducted using a PCR protocol based on 18 S ribosomal gene.Various prey organisms were uncovered,including dinoflagellate,diatom,green algae and plant,protozoa and metazoan.All these spatially coexisting six species showed different dietary diversity,with the food niche breadth(B)ranging from 1.00(Temora turbinate in morning)to 10.68(Calanopia elliptica in night).While food overlap between all these copepods were low,with the average value of the diet niche overlap index being approximately 0.09.Even temporally co-existing species sampled from the same time point fed on different groups of prey items with the food overlap index of 0.04 to 0.07 in midday and night but 0 in morning.As the most important dominant copepod in the Sanya Bay,Subeucalanus subcrassus seems to be capable to regulate its feeding,by exhibiting a rhythm of herbivorous feeding in midday and carnivorous feeding in morning and night,to better coordinate with other competitors for utilization of food resources.For most copepods,none of the prey items belonged to the dominant phytoplankton in the ambient water,indicating that copepod can better their survival by widening the choice of potential food resources in food limited environment.The dietary separation observed here might be important strategy for copepod to maintain population stabilization and thriving in the Sanya coastal waters. 相似文献
18.
关于对虾池混养中的几个问题 总被引：5，自引：0，他引：5
在两年围隔实验的基础上讨论了对虾池混养中存在的几个问题,认为：（1）虾池混养能够提高养殖产量和池塘氮磷的利用率,有助于缓解养殖对环境的污染,但由于养殖种类在池塘氮磷收支所占的比例很小,仅靠混养还不能彻底解决养殖污染问题;（2）罗非鱼与海产贝类的食物灶存在一定的分化。二者对虾池水质的影响具有互补性,因此虾鱼贝混养较虾鱼混养或虾贝混养效果更好。（3）对多个池塘组成的养殖系统的总体优化应是今后虾池生态系统结构优化研究的重要内容。 相似文献
19.
Jung-Hoon Kang 《Ocean Science Journal》2011,46(4):219-237
This study investigated the occurrence of Acartia copepods and their environmental characteristics to identify the existence and survival of foreign species at domestic ports
in Korea. Copepods samples were collected seasonally, and temperature, salinity, dissolved oxygen (DO), total suspended solids
(TSS), and chlorophyll-a (chl-a) were measured at the seaports Incheon, Gwangyang, and Ulsan from 2007 to 2009. No foreign species was found and all of the
Acartia copepods observed had been recorded in Korean waters previously. Acartia omorii, A. hongi, and A. pacifica were found at all three seaports, whereas portspecific species were found at Incheon (A. sinjiensis) and Ulsan (A. steueri, A. negligens, and A. danae). When chl-a and DO were not limited, eurythermal and euryhaline A. hongi, A. omorii, and A. hudsonica occurred at TSS concentrations between 38 and 183 mg·L−1, while warm-water copepods (A. pacifica, A. ohtsukai, A. sinjiensis, and A. erythraea) occurred at TSS concentrations <80 mg·L−1. The seasonal distributions of A. omorii, A. hongi, and A. pacifica at the three seaports were most significantly explained by temperature, salinity, DO, and TSS, and not chl-a. The variation in A. hudsonica and A. sinjiensis at Incheon was explained mainly by temperature, DO, and TSS, whereas A. erythraea at Ulsan was influenced only by chl-a. The occurrence of Acartia copepods showed spatiotemporal variation as a result of species-specific preferences or tolerances in each port environment.
Multiple regression analysis indicated that temperature, salinity, DO, and TSS were better predictors of the variation in
Acartia species at the seaports during the study than chl-a when food was not limiting. These results indicated that the occurrence of Acartia copepods and related environmental characteristics are crucial information for differentiating foreign species from the native
community and predicting the potential for foreign copepods to become established after their introduction to a seaport. 相似文献