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1.
2013年春季崂山湾浮游植物群落及其环境控制   总被引:4,自引:0,他引:4  
2013 年春季(3、4、5 月)对崂山湾海域浮游植物群落及其理化环境进行了3 个航次的调查研究。共鉴定浮游植物40 属75 种, 硅藻是调查区主要的浮游植物类群; 浮游植物细胞丰度平均为1.27×106个/m3,3 月份的平均丰度显著高于4、5 月份(P<0.01); 优势种主要为冰河拟星杆藻(Asterionopsis glacialis)、加拉星平藻(Asteroplanus karianus)、密联角毛藻(Chaetoceros densus)和夜光藻(Noctiluca scintillans), 浮游植物群落演替明显, 由3 月份硅藻控制逐步过渡到4、5 月份硅/甲藻共同控制; 相对较低的硝酸盐水平是导致4、5 月份浮游植物丰度显著低于3 月份的主要原因; 物种–环境数据的冗余分析(RDA)结果显示, 温度、硝酸盐含量是控制崂山湾春季浮游植物分布的重要环境因子。  相似文献   

2.
2014年春季渤海浮游植物群落结构   总被引:2,自引:1,他引:1  
张雪  王俊  高燕  王宏  马武  刘克奉  陈卫 《海洋科学》2020,44(6):45-55
基于2014年春季在渤海进行的水文、化学和生物方面的综合大面调查,研究了渤海浮游植物群落的结构特征,并结合文献资料,分析影响浮游植物群落结构形成的原因。结果显示:2014年渤海春季共鉴定浮游植物3门29属50种,以硅藻为主,还有少数甲藻和金藻。其中,硅藻门中圆筛藻属的种类最多,共12种,其次为角毛藻属,共5种。浮游植物总细胞丰度介于1.08×104~181.09×104个/m3,平均为25.47×104个/m3。硅藻与甲藻细胞丰度比值为12:1,硅藻在物种数量和细胞丰度上均占有绝对优势,为渤海浮游植物的主要类群。浮游植物优势种主要为密联角毛藻(Chaetoceros densus)、斯氏几内亚藻(Guinardia striata)、具槽帕拉藻(Paralia sulcata)和夜光藻(Noctiluca scintillans)。渤海春季浮游植物群落多样性水平较低,且分布不均。渤海中部和渤海海峡海域由于单一优势种过量繁殖导致群落稳定性较差。与历史同期资料对比,渤海海域浮游植物群落出现明显的物种演替现象,角毛藻的优势地位显著性下降,斯氏几内亚藻首次在渤海大面调查中被记录为优势种。本研究为今后渤海环境生态系统和渔业资源变动的研究提供重要基础资料和参考依据。  相似文献   

3.
分析了2009 年春季(5 月)渤海辽东湾网采浮游植物物种组成, 丰度分布, 生物多样性指数及群落相似性。春季共鉴定出浮游植物3 门23 属32 种, 主要隶属硅藻门和甲藻门, 生态类型多为温带近岸型和广布型种类, 少部分为暖海性物种或大洋性物种。优势种有夜光藻(Noctiluca scientillans)、翼鼻状藻(Proboscia alata)、旋链角毛藻(Chaetoceros curvisetus)、巨圆筛藻(Coscinodiscus gigas)和尖刺伪菱形藻(Pseudo-nitzschia pungens)等。浮游植物在各站位的细胞丰度分布不均匀, 其平面分布呈现由沿岸海域向海湾中部海域递减的趋势。Shannon-Wiener 指数、Pielou 指数较低, 群落结构简单, 稳定性较差。聚类分析结果表明群落之间的相似性较高。  相似文献   

4.
长江口海域春季浮游植物的年际变化   总被引:2,自引:0,他引:2  
林梅  李扬 《海洋与湖沼》2017,48(2):303-311
于2014年5月在长江口海域采集海水样品,分析了浮游植物种类组成、细胞丰度、优势种等群落结构特征。共鉴定浮游植物105种,其中硅藻30属56种,甲藻19属41种,以及隶属于金藻、蓝藻等的8个种。浮游硅藻以近岸半咸水种为主,优势种类是中肋骨条藻(Skeletonema costatum);浮游甲藻以沿岸广布种为主,典型代表是东海原甲藻(Prorocentrum donghaiense)。为了更好地了解长江口海域浮游植物的年际变化趋势,本文收集整理了该海域1986—2014年间的春季数据,分析了浮游硅藻、浮游甲藻主要群落特征的年际变化,以及浮游硅藻优势种类细胞粒径的变化趋势。结果表明:(1)浮游硅藻、浮游甲藻的种类数均呈现不同程度的上升趋势,浮游甲藻的上升幅度更为明显;(2)浮游甲藻种类数在浮游植物种类数中的占有比例呈上升趋势,而浮游硅藻所占比例呈下降趋势;(3)浮游硅藻优势种类的细胞粒径呈现小型化趋势。  相似文献   

5.
2014年冬季浙江中部海域网采浮游植物群集   总被引:1,自引:0,他引:1       下载免费PDF全文
于2014年12月至2015年1月, 在121°42′E~126°18′E, 28°43′N~30°02′N的浙江中部海域, 对97个站位采集的浮游植物的种类组成、群落结构、细胞丰度进行了研究。共鉴定浮游植物6门53属163种(含19未定种), 其中以硅藻为主, 甲藻其次; 浙江中部海域冬季浮游植物群落可分为4种生态类型: 半咸水类群、沿岸广温型、近海广温广盐型、外海高温高盐型, 其中最主要生态类型为近海广温型; 浮游植物优势种为中华齿状藻(Odentella sinensis)、琼氏圆筛藻(Coscinodiscus jonesianus) 、伏氏海线藻(Thalassionema frauenfeldii)、虹彩圆筛藻(Coscinodiscus oculus-iridis)、太阳双尾藻(Ditylum sol)、洛氏角毛藻(Chaetoceros lorenzianus)。浮游植物的细胞丰度范围为0.3×104个/m3~67.1×104个/m3, 平均值为8.8×104个/m3, 呈现近岸>近海>外海的分布特点, 高值区位于三门湾至渔山列岛之间的海域; 生物多样性指数平均值为3.36; Pearson 相关性分析得出: 调查海域浮游植物的细胞丰度与盐度呈负相关,与磷酸盐、硝酸盐成正相关。  相似文献   

6.
钱罡  魏玉秋  孙军 《海洋科学》2017,41(2):44-52
2015年春季, 在桑沟湾海域(122.48°E~122.64°E, 37.04°N~37.14°N) 21个站位进行了水文、生物和化学的综合调查, 应用Uterm?hl方法对调查海域浮游植物的物种组成、细胞丰度、优势物种以及群落多样性等相关生态特征进行了分析。结果表明, 本次调查共鉴定浮游植物4门36属70种, 主要由硅藻和甲藻组成, 也有少数的蓝藻和金藻出现, 浮游植物生态类型主要为温带近岸型。硅藻主要优势种为具槽帕拉藻(Paralia sulcata) 和离心列海链藻(Thalassiosira excentrica); 甲藻主要优势种为双刺原多甲藻(Protoperidinium bipes)。调查海域浮游植物细胞丰度范围为3×103~417.4×103个/L,平均值为130.76×103个/L。相比历史资料, 桑沟湾浮游植物物种数整体呈下降趋势。浮游植物细胞丰度的平面分布主要由硅藻分布所决定, 呈现中部较低, 逐渐向西部与东部增加的趋势; 其垂直分布呈现随水深的增加, 先降低后升高的趋势。浮游植物群落Shannon-Wiener多样性指数范围为0.486~2.305, 平均值为1.25; Pielou均匀度指数的区间范围为0.172~0.849, 平均值为0.462。由于Shannon-Wiener多样性指数和Pielou均匀度指数的高值区与浮游植物细胞丰度的低值区相对应, 从而说明优势种的出现会降低浮游植物的多样性。  相似文献   

7.
2009 年晚春黄海南部浮游植物群落   总被引:1,自引:0,他引:1  
在2009 年6 月对黄海南部及中部海域30 个站位进行综合调查, 对获得的131 个浮游植物样品用Uterm?hl 方法进行初步分析, 共鉴定浮游植物4 门51 属73 种(不包括未定名种), 其中硅藻32 属47种(不包括未定名种), 甲藻17 属24 种(不包括未定名种), 定鞭藻1 门1 种, 蓝藻1 门1 种, 硅藻在物种丰富度上占有优势。浮游植物的生态类型主要以温带近岸种为主, 优势物种为具齿原甲藻(Prorocentrum dentatum)、柔弱伪菱形藻(Pseudo-nitzschia delicatissima)、具槽帕拉藻(Paralia sulcata)等。调查区浮游植物细胞丰度介于0.089 × 103~1 045.200 × 103 个/L, 平均为15.941 × 103 个/L, 甲藻的细胞丰度要高于硅藻。细胞丰度高值区位于调查区的南部海域, 以具齿原甲藻为主, 垂向上在10 m 层出现最大值, 随着深度的增加丰度降低。调查区的Shannon-winner 多样性指数和Pielou 均匀度指数的平面分布基本一致, 并且与细胞丰度的分布呈相嵌形式, 即在细胞丰度高的区域多样性指数较低。  相似文献   

8.
夏季外海水入侵对大亚湾浮游植物群落结构的影响   总被引:1,自引:0,他引:1  
杨熙  谭烨辉 《海洋科学》2019,43(7):96-105
夏季大亚湾存在由粤东沿岸上升流所引起的外海水入侵现象,且入侵强度存在年际差异,作者利用大亚湾2004~2017年历年夏季航次调查数据,将弱入侵年份与强入侵年份进行对比分析,以探讨外海水入侵对大亚湾浮游植物群落结构的影响。结果显示,当外海水入侵由弱变强时,湾内水体理化特征发现显著变化,水体由高温低盐转变为低温高盐,N、P等营养盐含量出现下降。海水理化性质的改变导致了浮游植物群落结构的变化,硅藻、甲藻种类数以及浮游植物Shannon-wiener指数均出现升高;浮游植物总丰度和硅藻丰度下降,甲藻丰度变化不明显;常见浮游植物种类伪菱形藻属(Pseudo-nitzschiasp.)、角毛藻属(Chaetocerossp.)和叉角藻(Ceratiumfurca)丰度出现下降,而中肋骨条藻(Skeletonemacostatum)和菱形海线藻(Thalassionemanitzschioides)丰度出现升高;优势种由单一硅藻种类向硅藻和甲藻共为优势转变。此外,外海水入侵还会通过改变海水理化因子的空间分布以及湾内上层水体流向来影响浮游植物群落结构的空间分布。  相似文献   

9.
为了进一步了解霞浦长表岛附近海域浮游植物群落特征,文章利用2019年5月(春季)、9月(夏季)、12月(秋季)和2020年2月(冬季)4个航次调查的浮游植物和水环境数据,分析了浮游植物群落结构特征,通过冗余性分析(RDA)研究了影响浮游植物群落结构的主要环境因子,结果共鉴定出浮游植物4门60属170种,其中硅藻48属131种,甲藻10属26种,蓝藻1属2种,金藻1属1种。浮游植物以近岸广温广盐种和暖水种为主,全年优势种有13种,春季以东海原甲藻和夜光藻为主,夏季、秋季和冬季以中肋骨条藻和琼氏圆筛藻为主。浮游植物丰度在空间分布上整体呈现近岸高、远岸低、南部低、北部高的趋势特点。RDA和Person相关性分析表明,浮游植物丰度的季节动态变化主要受水温影响;春季和夏季适宜的温度与营养盐促进了浮游植物的大量增长,秋季和冬季则主要受到温度的影响。浮游植物大量繁殖增长甚至暴发出现在春季和夏季,霞浦长表岛海域滨海核电应在春季和夏季重点加强该海域赤潮灾害的监测预警。  相似文献   

10.
为阐明曹妃甸邻近海域浮游植物群落的水平和垂直分布特征,于2013年8月在该海域开展调查航次,应用Uterm9hl方法研究了浮游植物的物种组成、细胞密度和优势种等特征,采用冗余分析(RDA)和聚类分析探讨了浮游植物群落的空间分布特征及其与环境因子的关系。结果表明,本次调查共鉴定得到浮游植物3门34属66种,主要由硅藻和甲藻组成,浮游植物密度范围为(0.85~39.07)×10~4cells/L,主要优势种为长菱形藻(Nitzschia longissima)、中肋骨条藻(Skeletonema costatum)和浮动弯角藻(Eucampia zodiacus)等。浮游植物密度的空间分布与温度、盐度和营养盐等环境因子密切相关。水平方向上,近岸海域的细胞密度通常高于远岸海域,主要与陆源营养盐输入有关。垂直方向上,浮游植物群落的变化主要出现在水深超过20 m的远岸海域,细胞密度随深度增加而降低,大部分硅藻和甲藻主要分布在表层水体,而具槽帕拉藻(Paralia sulcata)等底栖种类主要分布在中层和底层水体,这些主要与海水的垂直混合受到抑制有关。  相似文献   

11.
鳚亚目 4 科 33 属 95 种,鰕虎鱼亚目 5 科 98 属 259 种,刺尾鱼亚目 5 科 11 属 65 种,鲈形目 19亚目 104 科 535 属 1799 种。  相似文献   

12.
Soil-sized particulates have been collected on board ship by a mesh technique from the lower troposphere of the North, Equatorial and South Atlantic Ocean, northern and southern Indian Ocean, South and East China Sea and various coastal localities.Spectrographic analysis reveals that, on average, the particulates have concentrations of Mn, Ni, Co, Ga, Cr, V, Ba, and Sr which are of the same order of magnitude as those in average crustal material. In contrast, the average concentrations of Pb, Sn, and Zn are one order of magnitude higher than those in average crustal material.Within this “world-wide” average there are significant geographical variations in the distributions of Pb, Sn, and Zn which may be related to anthropogenic sources.On the basis of trace-element distributions lower tropospheric soil-sized marine particulates have been divided into four genetic components; local, zonal, inter-zonal, and global. The proportions of these components vary geographically, and each component may have both a natural and an anthropogenic fraction.  相似文献   

13.
Tautog, Tautoga onitis, is an abundant species of fish in estuaries of the northeastern United States. Planktonic tautog larvae are abundant in summer in these estuaries, but there is little information on rates of growth of tautog larvae feeding on natural assemblages of food in the plankton. We examined abundance and growth of larval tautog and environmental factors during weekly sampling at three sites along a nearshore‐to‐offshore transect in Buzzards Bay, Massachusetts, USA during summer 1994. This is the first study of a robust sample size (336 larvae) to estimate growth rates of field‐caught planktonic tautog larvae feeding on natural diets, using the otolith daily‐growth‐increment method. The study was over the entire summer period when tautog larvae were in the plankton. The sampling sites contrasted in several environmental variables including temperature, dissolved oxygen (DO), and chlorophyll a concentration. There was a temporal progression in the abundance of tautog larvae over the summer, in relation to location and temperature. Tautog larvae were first present nearshore, with a pronounced peak in abundance occurring at the nearshore sites during the last 2 weeks in June. Larvae were absent at this time further offshore. From late June through August, larval abundance progressively decreased nearshore, but increased offshore although never approaching the abundance levels observed at the nearshore sites. The distribution and abundance of tautog larvae appeared to be related to a nearshore‐to‐offshore seasonal warming trend and a nearshore decrease in DO. Otoliths from 336 larvae ranging from 2.3 to 7.7 mm standard length had otolith increment counts ranging from 0 to 19 increments. Growth of larval tautog was estimated at 0.23 mm·day?1, and length of larvae prior to first increment formation was estimated at 2.8 mm indicating that first increment formation occurs 3–4 days after hatching at 2.2 mm. Despite spatial and temporal differences in environmental factors, there were no significant differences in growth rates at any of three given sites over time, or between sites. Because larval presence only occurred at a narrow range of temperature (17–23.5 °C) and DO (6.5–9.3 mg·l?1), in situ differences in growth did not appear to be because of differences in larval distribution and abundance patterns relative to these parameters.  相似文献   

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Concentrations of dissolved nutrients (NO3, PO4, Si), germanium species, arsenic species, tin, barium, dimethylsulfide and related parameters were measured along the salinity gradient in Charlotte Harbor. Phosphate enrichment from the phosphate industry on the Peace River promotes a productive diatom bloom near the river mouth where NO3 and Si are completely consumed. Inorganic germanium is completely depleted in this bloom by uptake into biogenic opal. The GeSi ratio taken up by diatoms is about 0·7 × 10?6, the same as that provided by the river flux, confirming that siliceous organisms incorporate germanium as an accidental trace replacement for silica. Monomethylgermanium and dimethylgermanium concentrations are undetectable in the Peace River, and increase linearly with increasing salinity to the seawater end of the bay, suggesting that these organogermanium species behave conservatively in estuaries, and are neither produced nor consumed during estuarine biogenic opal formation or dissolution. Inorganic arsenic displays slight removal in the bloom. Monomethylarsenic is produced both in the bloom and in mid-estuary, while dimethylarsenic is conservative in the bloom but produced in mid-estuary. The total production of methylarsenicals within the bay approximately balances the removal of inorganic arsenic, suggesting that most biological arsenic uptake in the estuary is biomethylated and released to the water column. Dimethylsulfide increases with increasing salinity in the estuary and shows evidence of removal, probably both by degassing and by microbial consumption. An input of DMS is observed in the central estuary. The behavior of total dissolvable tin shows no biological activity in the bloom or in mid-estuary, but does display a low-salinity input signal that parallels dissolved organic material, perhaps suggesting an association between tin and DOM. Barium displays dramatic input behavior at mid-salinities, probably due to slow release from clays deposited in the harbor after catastrophic phosphate slime spills into the Peace River.  相似文献   

18.
Three years of temperature data along two transects extending to 90 m depth, at Palau, Micronesia, show twice-a-day thermocline vertical displacements of commonly 50–100 m, and on one occasion 270 m. The internal wave occurred at a number of frequencies. There were a number of spectral peaks at diurnal and semi-diurnal frequencies, as well as intermediate and sub-inertial frequencies, less so at the inertial frequency. At Palau the waves generally did not travel around the island because there was no coherence between internal waves on either side of the island. The internal waves at a site 30 km offshore were out-of-phase with those on the island slopes, suggesting that the waves were generated on the island slope and then radiated away. Palau Island was thus a source of internal wave energy for the surrounding ocean. A numerical model suggests that the tidal and low-frequency currents flowing around the island form internal waves with maximum wave amplitude on the island slope and that these waves radiate away from the island. The model also suggests that the headland at the southern tip of Palau prevents the internal waves to rotate around the island. The large temperature fluctuations (commonly daily fluctuations ≈10 °C, peaking at 20 °C) appear responsible for generating a thermal stress responsible for a biologically depauperate biological community on the island slopes at depths between 60 and 120 m depth.  相似文献   

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In June 1981, dissolved Zn, Cd, Cu, Ni, Co, Fe, and Mn were determined from two detailed profiles in anoxic Baltic waters (with extra data for Fe and Mn from August 1979). Dramatic changes across the O2H2S interface occur in the abundances of Cu, Co, Fe, and Mn (by factors of ?100). The concentrations of Zn, Cd, and Ni at the redox front decrease by factors between 3 to 5.Equilibrium calculations are presented for varying concentrations of hydrogen sulfide and compared with the field data. The study strongly supports the assumption that the solubility of Zn, Cd, Cu, and Ni is greatly enhanced and controlled by the formation of bisulfide and(or) polysulfide complexes. Differences between predicted and measured concentrations of these elements are mainly evident at lower ΣH2S concentrations.Cobalt proved to be very mobile in anoxic regions, and the results indicate that the concentrations are limited by CoS precipitation. The iron (Fe2+) and manganese (Mn2+) distribution in sulfide-containing waters is controlled by total flux from sediment-water interfaces rather than by equilibrium concentrations of their solid phases (FeS and MnCO3). The concentrations of these metals are therefore expected to increase with prolonged stagnation periods in the basin.  相似文献   

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