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1.
We studied the characteristics of the phosphatase activity (Km and Vmax) in total seawater and in particulate material of the three main plankton classes (0.25-5, 5-90 and >90 microm) in a coastal marine ecosystem of Toulon Bay (French Mediterranean Sea). The measurement of the hydrolysis of sodium paranitrophenylphosphate (pNPP), a substrate of phosphatase, revealed low and high affinity components in unfiltered seawater and in particulate matter. In unfiltered seawater, the low affinity activity was predominant from October to March during phytoplankton development. The high affinity activity dominated from April to June and was significantly correlated with the bacterial abundances. The phosphatase behaviour in the particulate material differs from that in the unfiltered seawater. The activity of the three particulate classes was generally much lower than that of unfiltered seawater, particularly the low affinity activity. The >90 microm size fraction consisted in greater part of zooplankton. In this size class, the activity (nmol l(-1) h(-1)) of the low affinity component was predominant from May to August, when the abundance of the larvae of copepods (copepodites) was highest. Its high specific activity (Activity/Protein concentration as nmol l(-1) h(-1) microg(-1)) was particularly elevated during this period. The 5-90 microm fraction consisted of phytoplankton cells, especially Dinoflagellates. Between September and January, the activity (nmol l(-1) h(-1)) of this size class was mostly supported by the low affinity component. The specific activity (nmol l(-1) h(-1) microg(-1)) of the high affinity component was highest in June and August. No significant correlation was found between phosphatase activities and chlorophyll a or total cell abundance. In return temporary relationships with specific taxa exist in particular with Ceratium spp., Gymnodinium spp. and Protoperidinium spp. The contribution of the 0.25-5 microm size class exceeded rarely 20% of the total particulate activity. Between June and August, high specific activities (nmol l(-1) h(-1) microg(-1)) were observed for its high affinity component. In autumn, strong rainfall increased the phosphate and nitrate concentrations and led to a drop in salinity, which probably explains the low phosphatase activities (nmol l(-1) h(-1)) and cell densities observed during this period.  相似文献   

2.
基于2019-2020年4个季节的6个航次海上生态调查,研究黄河口邻近海域的浮游幼虫群落结构及其与环境因子的关系,旨在为海域生物多样性保护与重要生物资源养护提供科学基础.结果显示:在黄河口邻近海域,共鉴定出浮游幼虫16类,阶段性浮游幼虫是主要组成类群.浮游幼虫月均丰度以11月最高、1月最低.浮游幼虫香农-威纳多样性指数...  相似文献   

3.
This work investigates the alkaline phosphatase activity in a littoral marine ecosystem (Toulon Bay and Le Niel Bay, France) in order to study its biochemical characteristics with respect to pH, sea water composition and phosphate sensitivity. We also characterise the active forms in sea water and determine the extent to which zooplankton generate phosphatase activity with respect to other plankton classes. In Toulon Bay, phosphatase was produced mostly by the microplankton fraction (>90 μm), accounting for more than 90% of total activity. In contrast, most of the phosphatase activity in Le Niel Bay was generated by the nanoplankton fraction (5–90 μm) and the picoplankton fraction (0.25–5 μm). The microplankton enzymes had non Michaelis-Menten kinetics suggesting the involvement of multiple enzyme processes with distinct kinetic constants. This activity is in major part secreted into the sea water and is stimulated by the ionic strength and the pH of the sea water. Cypris larvae of the genus Balanus played a special role in this release. For the nanoplankton and picoplankton, part of this activity was due to non-secreted enzymes, probably bound to membranes or occurring intracellularly. Moreover, nano and picoplankton phosphatase required higher pH than microplankton enzyme. For all plankton size classes, there was no activity at low pH, suggesting that acid phosphatases were not involved in reactions with substrates dissolved in water.  相似文献   

4.
选择连云港近海临洪河口河心浅滩沉积物,采用不同浓度毒死蜱和重金属于室内培养,研究了毒死蜱和重金属对沉积物碱性磷酸酶和过氧化氢酶酶活性及其动力学特征的影响。研究结果表明:1)碱性磷酸酶活性受毒死蜱影响显著,峰值出现在10-200mg/kg浓度区间,培养第三周时Vmax显著下降,酶活性抑制作用最显著。2)毒死蜱对过氧化氢酶激活作用的峰值出现在50mg/kg处。培养三周,过氧化氢酶活性逐渐回归正常值。3)Cd处理对沉积物碱性过氧化氢酶和过氧化氢酶抑制作用显著,明显强于Pb处理以及Cd、Pb复合处理,而Pb在相当程度上缓解了Cd对两种酶的抑制作用。4)酶活性可以用来指示沉积物的早期污染状况。  相似文献   

5.
研究了2个育苗场不同发育期的中国对虾(Penaeus chinensis)幼体的异养菌和弧菌种群变化的动态过程。以典型特征法、BIOLOGGN法和数值分类法对菌株进行鉴定。结果表明,对虾幼体样品中所分离的细菌,大多是革兰氏阴性杆菌。鉴定为假单胞菌属(Pseudomonas)、气单胞菌属(Aeromonas)和弧菌属(Vibrio)。弧菌属主要为溶藻弧菌(Vibrioal-ginozyticus)和哈维氏弧菌(Vibrio harveyi)。在对虾幼体发育早期,假单胞菌(Pseudomonas)和气单胞菌(Aeromonas)占优势,随着对虾幼体的发育,弧菌(Vibrio)渐成为优势,其中溶藻弧菌(Vibrio alginolyticus)和哈维氏弧菌(Vibrio harveyi)优势明显。二者的消长与苗期病害的发生相关,溶藻弧菌总是在虾幼体健康时出现或成为优势,而哈维氏弧菌成为优势时,苗期病害容易发生。  相似文献   

6.
The temporal variations of mesozooplankton abundance and biomass (1-Volumetric method by settling volume and displacement volume and 2- Gravimetric method through wet weight, dry weight and ash-free dry weight) with relation to environmental parameters were studied in the mangrove creek area of Karachi coast, Pakistan. The data of mesozooplankton samples along with environmental parameters (temperature, salinity, pH, etc.) were collected during January 1998 to December 1998 from two creek stations. The abun-dance of mesozooplankton also exhibited seasonal trends at both stations. At Sta. S2, the highest and low-est abundance values were observed during post-monsoon and southwest monsoon respectively whereas, at Sta. S1, a clear trend of high abundance in pre-monsoon to low abundance in southwest monsoon was observed. Mesozooplankton abundance was also positively correlated with settling volume, displacement volume, wet weight and dry weight. The highest biomass value was observed in the northeast monsoon and pre-monsoon periods. The results of the canonical analysis of the output from the discriminate function was tested. Out of fifteen variables, only one was significantly different in single character ratios dry weight/ash free-dry weight (F3,23=4.78,P<0.005). The mesozooplankton community was collectively composed of 28 taxa. Among these groups, copepoda (66.3%), gastropod larvae (9.94%), evadne (4.60%), zoea (3.60%), cypris nauplii (2.56%), lemellibranch larvae (1.87%), chaetognaths (1.81%), ostracods (1.73%), lucifer (1.15%) and barnacles nauplii (1.35%) contributed the most to the similarities within Sta. S1, while copepoda (74.68%), cypris nauplii (5.29%), gastropods (4.87%), barnacles nauplii (4.81%), evadne (1.72%), zoea (1.53%) and ca-ridean larvae (1.18%) at Sta. S2. The remaining mesozooplanktonic group were accounted for less than 5% and 6% at Sta. S1 and Sta. S2 respectively, of the total organisms. Similarity perce  相似文献   

7.
2002-05-20-26在东海进行小尺度船基浮游生物生态系围隔实验,研究浮游动物的群落结构、组成与环境之间的关系,探讨了优势种群的自然繁殖发育期。结果表明,浮游动物的种类组成较简单,优势种明显。浮游动物生物量、丰度及优势种群丰度三者的变化呈逐渐增加趋势。在实验期的1~5d,小拟哲水蚤的无节幼虫和早期幼体占绝对优势,该自然种群的丰度不断增加;随时间推移,无节幼虫逐渐发育为桡足幼体,而后又逐渐发育为成体。因此,本次实验期是实验海区优势种小拟哲水蚤种群的自然繁殖发育盛期。  相似文献   

8.
A plume of herring larvae dispersing from a spawning site at Clythness in the Moray Firth (northern Scotland) was surveyed during early September 1985. Several cohorts of larvae were evident from the length distributions, and these were arranged in order of increasing length (age) towards the south-west. The spacing of cohort centres indicated a drift rate of 1–2 km day−1.Calanoid copepod nauplii constituted the major proportion of the diet of larvae <10 mm sampled during the study. Cyclopoid copepod nauplii and gastropod veligers were not found in the diet although they were present in the water. The distribution of nauplii in the region was inversely correlated with the concentration of phytoplankton chlorophyll, and nauplii concentrations were above average in the vicinity of the herring spawning site. The drift trajectory of the herring larvae took them towards an area of high copepodite and adult copepod concentration—items which formed an increasing part of the diet of larger (older) larvae.  相似文献   

9.
《Oceanologica Acta》2003,26(2):179-189
Respiration, excretion (NH4 and PO4) and feeding of zooplankton from the upper 200 m of the Almeria–Oran frontal region (western Mediterranean), were studied during winter 1997. Eight sites belonging to the three main hydrodynamic structures of the area (Mediterranean water, geostrophic Atlantic jet and associated anticyclonic gyre) were considered. Lowest values of respiration, PO4 excretion, O/P atomic ratio and particle ingestion were found in Mediterranean waters. At the frontal limit, respiration and ammonium excretion were enhanced compared to the adjacent structures (Mediterranean water and Atlantic jet). In the gyre water, lowest O/N and highest N/P values were observed and maximum faecal pellet production and reproduction activity (inferred from the proportion of nauplii in plankton) were recorded. Selectivity was observed for feeding with respect to particular spectra. At the front and in the jet, large particles (> 20 μm), were preferred, while medium- and small-sized particles were mainly used for food at the gyre and in Mediterranean water. As the bulk of zooplankton components was the same at all the stations, physiological variations were interpreted as adaptive processes to qualitative and quantitative changes in the food resource, i.e. Mediterranean scarcity and Atlantic water richness, “new production” of diatoms at the front limit, enhancement of the microbial food chain at the gyre and in Mediterranean waters. The maximum proportion of copepod nauplii observed at the gyre could result, either from an isopycnal transport from the front, of larvae issued from eggs produced at the frontal limit, or from a local enhancement of copepod reproductive activity induced by the favourable food conditions prevailing at the gyre, as suggested by the increase of faecal production.  相似文献   

10.
Crustacea experience periods of starvation during moulting or when limited food availability occurs. The effects of starvation on Crustacea physiological responses have been demonstrated, whereas the effects of starvation on Crustacea immune parameters remain to be more fully studied. In the present study the effects of starvation on immune parameters and antioxidant enzyme activities of the crab Carcinus aestuarii were evaluated for the first time. Treated crabs were starved for 7 days, whereas control crabs were fed daily with mussels. Total haemocyte count (THC), haemocyte diameter and volume, haemocyte proliferation, cell-free haemolymph (CFH) glucose and total protein levels, and phenoloxidase (PO) activity in both haemocyte lysate (HL) and CFH were measured in crabs. In addition, superoxide dismutase (SOD) and catalase (CAT) activities were evaluated in both gills and digestive gland from crabs, in order to evaluate whether starvation induced oxidative stress in C. aestuarii. THC increased significantly in starved crabs, with respect to controls, whereas no significant variations were observed in haemocyte diameter, volume and proliferation. In CFH of starved animals glucose concentration significantly increased, whereas total protein concentration significantly reduced. A significantly higher PO activity was recorded in HL from starved crabs, than in control crabs. Conversely, PO activity did not vary significantly in CFH. Starvation did not cause significant alterations in antioxidant enzyme activities in both gills and digestive gland. Results obtained demonstrated that starvation influenced crab immune parameters, but did not induce oxidative stress. Results also indicated that C. aestuarii can modulate its cellular and biochemical parameters in order to cope with starvation.  相似文献   

11.
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   

12.
人工增殖放流是恢复鲎资源最有效、最迅速的方法, 而了解和掌握环境因子对中国鲎(Tachypleus tridentatus)幼鲎生长状况的影响规律, 进而选择适宜放流的时间和海区, 是保证人工放流得以成功的关键。本文在实验室条件下, 研究了不同盐度(5‰、10‰、15‰、20‰、25‰、30‰、35‰、40‰)对中国鲎幼鲎成活率、蜕壳率、蜕壳增重率、Na+-K+-ATP酶活性、免疫酶活性、抗氧化酶活性等的影响, 探讨了不同盐度水平下中国鲎幼鲎生长、蜕壳、渗透调节能力、机体免疫力和抗氧化能力等的变化。养殖试验持续56d, 结果表明: 不同盐度对中国鲎幼鲎的成活率、蜕壳率、二龄幼鲎均重及蜕壳增重率均有显著影响(P<0.05), 且均随盐度升高呈先升高后降低的趋势; 蜕壳率和蜕壳增重率与盐度的回归分析均表明, 中国鲎幼鲎蜕壳与生长的最适盐度分别为24.10‰和24.94‰; 一龄和二龄幼鲎的Na+-K+-ATP酶活性均随盐度的升高呈先显著升高后显著降低趋势(P<0.05); 35‰和40‰盐度试验组一龄幼鲎的酸性磷酸酶(acid phosphatase, ACP)活性显著高于其他试验组, 而5‰盐度试验组一龄幼鲎的碱性磷酸酶(alkaline phosphatase, AKP)活性显著低于25‰试验组(P<0.05) ; 盐度对二龄幼鲎的ACP、AKP和溶菌酶(lysozyme, LZM)活性均没有显著影响(P>0.05); 35‰和40‰试验组一龄幼鲎的过氧化氢酶(catalase, CAT)活性显著高于盐度较低试验组(P<0.05); 二龄幼鲎的谷胱甘肽过氧化物酶(glutathione peroxidase)活性随着盐度的升高而升高, 盐度10‰试验组显著低于30‰和40‰试验组(P<0.05)。研究结果显示盐度对中国鲎幼鲎生长、蜕壳、Na+-K+-ATP酶活性、免疫指标和抗氧化能力均有显著影响, 蜕壳最适宜的盐度在24‰~25‰左右, 盐度过高或过低都将引起幼鲎生长率和成活率降低, 渗透调节能力、免疫力和抗氧化力显著下降。  相似文献   

13.
本文研究了13个2-(N-芳基氨甲基)苯并异噻唑啉-3-酮类化合物对球等鞭金藻Isochrysis galbana、亚心形扁藻Platymonas subcordiformis及舟形藻Navicula的生长抑制性能,并测试了其对藤壶二期无节幼虫的生物活性。结果表明:2-(N-芳基氨甲基)苯并异噻唑啉-3-酮类化合物对球等鞭金藻、亚心形扁藻和舟形藻都有良好的生长抑制活性,其中对球等鞭金藻和亚心形扁藻的抑制作用较强;对藤壶幼虫的生物活性测试表明,化合物最低质量浓度为2.0 mg/L时,除化合物g和l,都具有良好的生长抑制活性。化合物的结构与浮游生物的生长抑制活性关系表现为间位取代优于对位取代。  相似文献   

14.
为了解西沙群岛珊瑚礁海域浮游动物的群落特征, 于2015年5月末至7月初在西沙群岛8个岛礁(七连屿、永兴岛和东岛3个岛屿以及浪花礁、盘石屿、玉琢礁、华光礁和北礁5个环礁)进行了浮游动物采样, 分析了浮游动物的多样性、丰度和群落结构特征, 并比较了5个环礁潟湖内和向海礁坡区浮游动物群落组成的差异。调查海域共鉴定浮游动物180种(包括浮游幼虫13个类群), 其中桡足类最多, 达83种, 其次是水母类(38种)、浮游软体类(14种)、毛颚类(11种)和浮游被囊类(7种); 浮游动物平均丰度为256.4±117.8个·m-3, 桡足类占总丰度的51.08%, 其次是浮游幼虫(16.30%)、浮游被囊类(13.22%)和毛颚类(7.70%)。浮游动物种数、多样性和均匀度指数、丰度在岛屿和环礁之间以及环礁的潟湖区和向海礁坡区均存在差异; 浮游动物多样性和丰度在东岛、玉琢礁和华光礁较高, 而在七连屿和北礁较低; 5个环礁向海礁坡区的浮游动物多样性和丰度皆高于潟湖区的。多元统计分析结果表明调查岛礁的浮游动物可划分两个聚群(相似水平85%); 岛屿近岸及环礁的潟湖群落(Ⅰ)和岛屿远岸及环礁的向海礁坡群落(Ⅱ); 两个聚群浮游动物组成差异较显著(r=0.832, p<0.001); 前者的种数、多样性指数、总丰度和主要浮游动物类群如桡足类、毛颚类和浮游幼虫的丰度显著低于后者。环礁潟湖区和向海礁坡区的空间异质性和生态环境差异可能是导致浮游动物群落结构呈现不同特征的主要因素。  相似文献   

15.
张光涛  孙松 《海洋学报》2011,33(2):146-156
根据西北冰洋43个调查站位的浮游动物种类组成和数量资料,分析了浮游动物的群落结构和地理分布特征,探讨了浮游动物群落与环境因子的关系.结果表明,在调查区域存在三种不同的浮游动物群落类型:楚科奇海台和加拿大海盆地区的高纬度深海群落;楚科奇海中部的陆架群落;阿拉斯加沿岸和楚科奇海北部的沿岸过渡群落.深海群落浮游动物数量较少,...  相似文献   

16.
2010年夏季雷州半岛沿岸海域浮游动物群落结构特征   总被引:4,自引:1,他引:3  
2010年7月对雷州半岛海岸带的浮游动物群落结构及相关环境因子进行了调查,共鉴定出浮游动物87种和34类浮游幼体,其中原生动物4种,占总种类数的4.6%;腔肠动物20种,占总种类数的23.0%;介形类1种,占总种类数的1.1%;枝角类2种,占总种类数的2.3%;桡足类37种,占总种类数的42.5%;十足类2种,占总种类数的2.3%;毛颚动物7种,占总种类数的8.0%;被囊动物6种,占总种类数的6.9%;浮游软体动物8种,占总种类数的9.2%。优势种有13种和3类浮游幼体,孔雀强额哲水蚤和小毛猛水蚤是该海域重要的优势种群,几乎在全海域均为优势种,桡足类幼体为全海域优势类群。半岛沿岸海域浮游动物种类数由近岸往远岸逐渐增多,浮游动物丰度分布则相反。浮游动物种类数由多到少的顺序为东北部、东南部、西北部和西南部、南部,丰度由大到小的顺序为西北部、西南部、东北部、东南部、南部,生物量由大到小的顺序为东北部、西南部、西北部、东南部、南部,浮游动物丰度和生物量的平面分布反映了人类对海岸带开发利用的活动概貌。多样性指数和均匀度平均值分别为2.96和0.57。相关分析表明:浮游动物丰度与水温、细菌总数、浮游动物生物量均呈极显著的正相关关系,与磷酸盐呈显著的负相关关系;浮游动物生物量与TOC、细菌总数、叶绿素a、浮游植物丰度均呈极显著的正相关关系,与pH呈显著的正相关关系,与盐度呈显著的负相关关系。  相似文献   

17.
花尾胡椒鲷仔稚鱼期消化酶活性的变化   总被引:12,自引:0,他引:12  
本文研究了花尾胡椒鲷仔、鱼发育时期不同日龄的三种消化酶活性的变化。早期仔鱼已具有一定的蛋白酶、淀粉酶和脂肪酶活性,蛋白酶比活力在仔稚鱼转变期和稚鱼向幼鱼转变时明显下降,淀粉酶活笥随日 龄增加呈下降趋势,内源营养向外源营养转换过程中,脂肪酶活笥先升后降,进入于期后比活力迅速再次提升。结果表明,消化酶活笥的变化与他、稚鱼发育过程中开矿变化具相关性。混合营养期结束后。13日 龄仔鱼的三种酶活性均下降,且  相似文献   

18.
Seasonality of Plankton Assemblages in a Temperate Estuary   总被引:3,自引:0,他引:3  
Abstract. Synoptic measurements of temperature, salinity, nutrients, primary productivity, chlorophyll a, and abundance and composition of phytoplankton, zooplankton, and ichthyoplank-ton were made over an annual cycle on the Peconic Bay estuary (Long Island, New York, USA). There were pronounced seasonal fluctuations in all variables measured. During the warmer season, the plankton was dominated by nanophytoplankton (athecate microflagellates and chlorophytes, short chains of diatoms), small zooplankton (copepod nauplii, copepodites, and adults of small copepod species) and gelatinous carnivores (ctenophores and medusae). During the colder season, the plankton was dominated (in terms of primary productivity and chlorophyll a) by netplankton, larger zooplankton (adult copepods) and fish larvae. The winter bloom of apparent netplankton (> 20 μm fraction) was largely an artifact of the screening method employed, in that long chains of a diatom with small individual cell size (Skeletonema costatum) comprised 84.4–97.8% of the phytoplankton present. There was a significant negative relationship over the year between length of diatom chains and number of smaller zooplankton. For this reason, as well as initiation of the winter bloom during a period of declining levels of both light and zooplankton, inception of the bloom appeared more related to release of zooplankton grazing pressure than to illumination. Temporally offset pulses of ctenophores and other zooplankton during the warmer season suggest substantial predation by ctenophores. Apparent decimation of copepod populations by ctenophore predation in late summer and fall immediately preceeded inception of the winter diatom bloom. Larval Ammodytes americanus were the dominant ichthyoplankton, and these co-occurred in winter with increased abundances of larger adult copepods of species upon which A. americanus is known to feed. With certain modifications the patterns recorded for Peconic Bay corresponded to both of two generalized trophic pathways proposed by Greve & Parsons (1977) for temperate waters: nanoplankton → small zooplankton → gelatinous zooplankton carnivores or netplankton → larger zooplankton → young fish. The former pattern characterized the warmer season, and the latter the colder season. Comparison of patterns in Peconic Bay with those in some other temperate estuarine and coastal waters suggests similarity, particularly for estuaries of the northeastern United States.  相似文献   

19.
We investigated the seasonal variation of the neustonic zooplankton community in the surface layer (above 30 cm in depth) of 16 stations in southern waters of Korea from April 2002 to April 2003. In the neustonic community, copepods accounted for 59% of total organisms, as the most predominant group, while other dominant groups were invertebrate larvae, cladocerans, tunicates and fish eggs. Pontellid copepods, a major group of neustonic zooplankton, showed a marked seasonal variation and displayed a significant positive correlation with temperature (P < 0.05). Fish eggs appeared from spring to early summer in the inshore waters while tunicates and oceanic copepods (Eucalanus spp. and Euchaeta spp.) were dominant in the offshore waters during high temperature periods. This suggests that the distribution pattern of the neustonic zooplankton is seasonally affected by the hydrological conditions of in- and offshore waters. The abundance of zooplankton was higher in the surface layer (< 15 cm) than in the subsurface layer (15–30 cm), and was also higher at night than during the daytime. Of the dominant copepod families, the density of acartiid and pontellid copepods was higher in the surface layer than the subsurface layer. The density of acartiid and corycaeid copepods was significantly higher during daytime than nighttime. This indicates that the surface layer in temperate regions may provide a favorable habitat for neustonic copepods despite the dynamic environmental fluctuations.  相似文献   

20.
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   

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