深圳湾海域赤潮生物演变及赤潮预警关键因子分析

2020年5月初,深圳湾海域发生近5年来首次赤潮, 面积达到6 km2, 前期赤潮优势种为中肋骨条藻(Skeletonema costatum), 后期转变为赤潮异弯藻(Heterosigma akashiwo)。布放于深圳湾海域的海洋环境综合浮标自动监测到了赤潮发生过程的海水水质和生态数据变化: 赤潮发生前(4月底)硝酸盐和磷酸盐均大幅升高; 赤潮发生期间, 叶绿素a浓度迅速升高, 最高值达到127.1 μg·L-1(5月2日), 海水温度持续升高, 盐度整体下降; 5月4日开始, 赤潮逐渐消散, 当日水温日均值达到28 ℃以上, 风力也开始升高, 盐度则继续降低。经研究分析, 本次深圳湾赤潮的主要调控因素可能是水温, 活性磷酸盐大幅升高可能是引发中肋骨条藻大规模增殖的诱因, 而赤潮后期的陆源水体输入导致的悬浮物增加导致了赤潮快速消亡。本次赤潮优势种从硅藻到针胞藻的转变, 主要原因可能是赤潮前期磷酸盐快速消耗导致的磷供应不足。通过数据分析发现, 近十几年来, 深圳湾海域赤潮生物逐渐从硅藻转变为甲藻及其他藻类, 其原因与海域氮磷比持续升高、磷成为限制因子有关, 故海域赤潮监测预警应重点关注磷酸盐的变化。     

厦门海域2011年中肋骨条藻和血红哈卡藻赤潮期间细菌群落结构变化

【目的】研究2011年8月厦门海域爆发的由中肋骨条藻和血红哈卡藻共同引发的赤潮生消过程中细菌群落结构变化。【方法】应用变性梯度凝胶电泳技术(Denaturing gradient gel electrophoresis,DGGE)对两个赤潮站位和一个非赤潮站位的细菌群落结构进行研究。通过DGGE图谱分析确定赤潮生消过程中细菌群落中的关键菌群,借助Canoco软件分析细菌菌群与环境因子的相关性。【结果】在赤潮起始阶段细菌的群落结构与pH、N/P的相关性较大,在赤潮消亡阶段细菌的群落结构与盐度、温度呈明显的正相关。γ变形杆菌(Gammaproteobacteria)(47.7%)在赤潮期间处于主导位置,假交替单胞菌属(Pseudoalteromonas)、假单胞菌属(Pseudomonas)、交替单胞菌属(Alteromonas)、噬氢菌属(Hydrogenophaga)、Actibacter、Oleibacter等属均为优势菌群。香农-威列多样性指数表明,赤潮站位细菌多样性随着赤潮生消呈先升高后降低趋势,而非赤潮站位细菌多样性基本保持不变。通过Canoco对细菌菌群的主成分分析发现,在赤潮开始阶段Hydrogenophaga属为优势菌群,而在赤潮消退阶段则以Pseudomonas和Pseudoalteromonas属为主。赤潮站位藻际细菌和游离细菌群落多样性在藻密度较大时均达到最大值,然而两者与环境因子的相关性有较大差别。【结论】研究结果表明赤潮站位细菌群落多样性远高于非赤潮站位,细菌丰度随着赤潮藻密度的升高而增加,细菌与赤潮藻有着密切的关系。本文首次研究了多种优势藻引发的赤潮环境下细菌群落结构的变化,这对于多种藻引发的赤潮生消过程中细菌菌群结构有了深入的了解,为赤潮调控的研究提供了理论依据。     

湛江港湾潜在赤潮生物的时空分布及其影响因素

2009年2月(冬)、5月(春)、8月(夏)和11月(秋)分别对湛江港湾的浮游植物和环境因子进行了调查,并对该海域潜在赤潮生物的时空分布及其影响因素进行了分析。结果表明,湛江港湾海域潜在赤潮生物共有126种,其中硅藻门26属85种,占潜在赤潮生物种类数的67.5%,甲藻门14属36种,占潜在赤潮生物种类数的28.6%,蓝藻门1属2种,占潜在赤潮生物种类数的1.6%,金藻门2属2种,占潜在赤潮生物种类数的1.6%,针胞藻纲1属1种,占潜在赤潮生物种类数的0.8%。种类数以春季最多,达89种,秋季次之,为71种,夏季61种,冬季最少,仅有58种。细胞丰度在12.36×104～43.55×104cells·L-1,春季最高,夏季次之,冬季最低,从各主要优势种的细胞丰度和细胞大小判断,该海域潜在赤潮生物的丰度均未达到赤潮发生的阈值。4季均出现的种类共有31种,季节相似性指数在0.43～0.50。优势种共有19种,全为硅藻,没有观测到甲藻。优势度最大的种类主要有浮动弯角藻(Eucampia zoodiacus)、旋链角毛藻(Chaetoceros curvisetus)和中肋骨条藻(Skeletonema costatum),没有全年优势种。中肋骨条藻、旋链角毛藻和冰河拟星杆藻(Asteri-onellopsis glacialis)为3季优势种。分析表明,潜在赤潮生物细胞丰度与叶绿素a、水温、盐度和pH值存在着极显著的正相关,与DIN和SiO32-存在着极显著的负相关,与PO43-不存在显著相关关系。     

广州珠江口海域中肋骨条藻的周年变化及其与环境因子的关系

2004年3月至2005年3月对广州海域(22°33′～22°41′N,113°37′～113°42′E)进行了调查研究,分析结果表明,广州海域中肋骨条藻数量的空间平面分布不均匀,分布格局呈内河口向外河口递增的趋势;中肋骨条藻数量的季节波动模式为单峰型;中肋骨条藻的密度与活性磷酸盐含量存在显著的负相关关系,与硅酸盐含量存在显著的正相关关系;与温度、盐度、亚硝酸盐、铵盐、透明度、硝酸盐、COD及pH的相关性不显著,但与DO存在一定的正相关性,但相关性均不显著;活性磷酸盐和硅酸盐是广州海域中肋骨条藻的主要影响因素。     

水东湾海域浮游植物潮汐分布特征及其与环境因子的关系

2014年秋、冬两季,每个季节在大潮期和小潮期对水东湾海域浮游植物群落结构和环境因子进行了调查,共鉴定出4门57属134种。其中硅藻门42属106种,占浮游植物种类数的79.1%;甲藻门13属26种,占浮游植物种类数的19.4%;蓝藻门1属1种,占浮游植物种类数的0.8%;针胞藻纲1属1种,占浮游植物种类数的0.8%。优势种15种,主要为尖布纹藻Gyrosigma aluminatum、圆海链藻Thalassiosira rotula、中肋骨条藻Skeletonema costatum、丹麦细柱藻Leptocylindrus danicus和舟形鞍链藻Campylosira cymbelliformis等。4个航次共有种类数在18—40种,Jaccard种类相似性指数范围在0.200—0.404,多样性指数和均匀度平均值分别为2.60和0.60。秋季大、小潮期多样性指数差异较显著(P0.05),冬季细胞丰度、多样性指数和均匀度大、小潮期均无明显差异。浮游植物细胞丰度变化范围为0.95×10~4个/L—28.0×10~4个/L,平均为6.86×10~4个/L,平均丰度冬季小潮期(9.46×10~4个/L)秋季小潮期(7.56×10~4个/L)冬季大潮期(5.97×10~4个/L)秋季大潮期(4.44×10~4个/L)。主成分分析(PCA)表明:盐度和营养盐可能是影响水东湾海域生态环境的主导因子。对水东湾海域浮游植物群落结构与主要环境因子进行Spearman相关性分析,细胞丰度与盐度在秋季大、小潮期为负相关,在冬季大、小潮期呈显著正相关;与无机氮和磷酸盐在冬季大、小潮期呈极显著负相关,在秋季大、小潮期均无相关性。冬季小潮期水温与多样性指数、均匀度和细胞丰度均呈正相关;从测定结果来看浮游植物细胞丰度、多样性指数和均匀度与叶绿素a含量均无统计学意义上的相关性。     

不同pH对双胞旋沟藻和血红哈卡藻生长及光合特性的影响

双胞旋沟藻(Cochlodinium geminatum)和血红哈卡藻(Akashiwo sanguinea)是我国近海的两种赤潮藻种。研究了不同pH(8.30、7.80、6.80)值对上述两种甲藻的生长及光合作用特性的影响。研究结果表明: 经过一段时间的培养, 不同pH值下两种甲藻的细胞密度产生了差异, 与对照组(8.30)相比, 7.80组无显著性, 6.80组则呈现显著性下降(p<0.05)。在两种甲藻的三组实验培养结束时, 经单因素方差分析结果表明, 7.80组藻细胞的叶绿素a含量、最大光合效率(Fv/Fm)、最大相对电子传递速率(rETR)与对照组差异不明显, 6.80组与对照组均表现出显著性降低(p<0.05), 说明弱酸pH值条件对两种甲藻的光合特性具有抑制作用。     

舟山海域春季浮游植物生物量及东海原甲藻赤潮频发机制初探

通过2002和2003年春季2个航次对东海舟山群岛及其邻域大面站的浮游植物及期间爆发的大规模东海原甲藻(Prorocentrum donghaiense)赤潮的综合调查,研究了调查海区浮游植物叶绿素a和营养盐的分布特性,分析了赤潮高发区域的生态环境特征,探讨了诱发和控制海域赤潮发生的环境因子.结果表明,2002和2003年春季大面站表层平均叶绿素a浓度分别为1.09±1.63和4.21±5.33 mg·m^-3,调查海区平均为0.70±0.48和2.60±2.99 mg·m^-3,叶绿素a浓度的高值区基本上位于122.5°～123°E间冲淡水形成的锋面区域,此区域营养盐可以得到充分补充,光照条件适宜,也是浮游植物生产力的高值带.2002和2003年东海原甲藻赤潮跟踪期间,表层平均叶绿素a浓度分别高达18.45±11.04和12.47±8.15 mg·m^-3.赤潮发生海域盐度在26～30,赤潮藻生长易受磷的限制.光照条件适宜、营养盐(特别是磷酸盐)能得到较快的补充及锋面辐聚带的形成是赤潮形成的重要条件.     

汉沽盐场浮游植物生态特征

2012年5—12月,对渤海湾长芦汉沽盐场盐度从5~20!Bé逐级升高的5个盐池进行了卤水理化指标以及浮游植物种类和丰度分析。结果表明:调查取样鉴定检测出浮游植物共5门27种,其中硅藻18种,占绝对优势;各盐度盐池中(A1~A5)蓝藻门颤藻(Oscillatoria spp.)均为优势种,硅藻门菱形海线藻(Thalassionema nitzschioides)、中肋骨条藻(Skeletonema costatum)、菱形藻(Nitzschia spp.)和圆筛藻(Coscinodiscus spp.)等在较低盐度盐池中(A1和A2)占优势,而绿藻门杜氏藻(Dunaliella spp.)在中高盐度盐池中(A3~A5)为优势种;不同盐度盐池中浮游植物密度为6.47×103~5.07×106ind·L-1,多样性指数为0.13~1.57,均匀度为0.01~0.58,优势度均0.5,且均随盐度和季节呈规律性变化。总体而言,汉沽盐场浮游植物种群多样性和均匀度较低,优势度明显,且随卤水盐度升高和温度降低,浮游植物多样性和密度降低。     

微微型藻华爆发海域硅酸盐与叶绿素a分布特征研究

以南戴河近岸海域为研究对象,分析了该海域2009年5~10月份硅酸盐和叶绿素a的时空分布特征,并初步探讨了它们与微微型藻华的关系。结果表明:整个调查期间该海域硅酸盐平均含量为0.67±0.31 mg·L^-1,叶绿素a平均含量为2.06±1.16 ug·L^-1;其平面分布呈现近岸高、远岸低的特点;硅酸盐平均含量9月最高、5月最低;叶绿素a平均含量在8~9月高、5~6月低;微微藻赤潮期间海域硅酸盐和叶绿素a平均含量明显高于未发生微微藻赤潮的2008年同期。叶绿素a与硅酸盐浓度呈现出正相关关系,在微微藻赤潮爆发期间尤为显著,可能是因为微微型浮游植物大量生长抑制了硅藻等消耗硅酸盐藻类的正常生长繁殖所致。     

球形棕囊藻赤潮消亡过程环境因子变化及其消亡原因

针对2014年2月北部湾近岸海域的2次球形棕囊藻赤潮,分析了球形棕囊藻赤潮消亡过程的环境变化,探讨了球形棕囊藻赤潮消亡的原因。结果表明:棕囊藻赤潮发生期各站点球形棕囊藻的胶质囊泡密度为200~3000个·m-3,细胞密度为1.8×107~1.5×108cells·L-1,而赤潮消亡期各站点球形棕囊藻的胶质囊泡密度为1~200个·m-3,细胞密度为1.0×106~8.3×107cells·L-1,监测期间胶质囊泡和细胞密度呈下降趋势,赤潮逐步消亡;赤潮消亡时主要环境因子变化特征显著,水温、p H值、DO及COD含量呈下降趋势,活性磷酸盐及部分站点无机氮浓度较低,氮磷比呈上升趋势;温度降低、盐度升高和磷酸盐的限制影响球形棕囊藻的生长繁殖,很可能是直接导致球形棕囊藻赤潮消亡的主要原因。本研究为今后球形棕囊藻赤潮的预警和治理提供重要依据。     

东海赤潮高发区COD和石油烃分布特征及其与赤潮发生关系的初步研究

根据2002年4月25日-5月2日对东海赤潮高发区化学耗氧量（COD）、石油烃等项目的现场调查,探讨了该海区COD、石油烃以及富营养化指数（EI）的分布特征,结果表明,COD和富营养化指数（EI）表明,COD和海水富营养化程度高,是调查海区赤潮发生的必要条件,有合适的温盐和光照条件下,当海水EI和COD浓度分别处在2.5-15和0.8-1.4mg·L^-1范围内可导致赤潮发生。     

Chemotaxis towards inorganic phosphate in the red tide alga Chattonella antiqua

The red tide flagellate, Chattonella antiqua, was shown to beattracted to inorganic phosphate in both aged seawater and artificialseawater by well-test assays.     

Virioplankton community structure along a salinity gradient in a solar saltern

The virioplankton community structure along a salinity gradient from near seawater (40 per thousand ) to saturated sodium chloride brine (370 per thousand ) in a solar saltern was investigated by pulsed-field gel electrophoresis. Viral populations with genome sizes varying from 10 kb to 533 kb were detected. The viral community structure changed along the salinity gradient. Cluster analysis of the viral genome-banding pattern resulted in two main clusters. The virioplankton diversity within the samples with salinity from 40 per thousand to 150 per thousand was on the same cluster of a cladogram. The other group consisted of virioplankton from samples with salinity above 220 per thousand. The virioplankton diversity in the different samples was calculated using the Shannon index. The diversity index demonstrated an increase in diversity in the samples along the gradient from 40 per thousand to 150 per thousand salinity, followed by a decrease in the diversity index along the rest of the salinity gradient. These results demonstrate how viral diversity changes from habitats that are considered one of the most common (seawater) to habitats that are extreme in salt concentrations (saturated sodium brine). The diversity index was highest in the environments that lie in between the most extreme and the most common.     

The association between algae organisms and environmental factors in Hai-tan Strait of Fujian,China

27 points were surveyed, and then algae and seawater samples were collected in Hai-tan Strait. The correlation on HAB (harmful algae blooms) species and environmental factors were studied. Water temperature (T) and salinity (S) ranging from 11.9 °C to 27.8 °C and 20.4 to 33.7 in the year, respectively. Dissolved inorganic nitrogen (DIN) in surface water ranged from 0.098 to 0.776 mg·L^?1, PO₄-P ranged from 0.0016 to 0.0729 mg·L^?1. And Eutrophication index (E) ranged from 0.03 to 13.8, varied different. 102 species of algae belonging to 4 classes and 52 genera were identified. The diversity was increasingly from winter to summer, decreasingly from summer to autumn, highest in summer. 49 species of red tide organisms were found in Hai-tan Strait, main two classes were Bacillariophyta and Pyrrophyta. Ceratium tripos and Noctiluca scintillans were dominant species in spring, Skeletonema costatum was common, and was also mainly HABs dominant species in summer, autumn and winter. Pearson correlation and Canonical correspondence analysis (CCA) showed that environment factors had significant correlation with dominance HABs species in different extent, and the ordination result was that S(Salinity) > T(Temperature) > pH > E(Eutrophication index) > DO(dissolved oxygen) > DIN > PO₄-P. Prorocentrum donghaiense, Skeletonema costatum, Noctiluca scintillans and Karenia mikimotoi caused many times red tide in 2011 to 2016. However, Prorocentrum donghaiense and Karenia mikimotoi cell density was low in survey year. North of the strait and east coast of the southern strait were sensitive sea area of red tide. The work highlights for the first time ecological characteristic of HAB was studied in Hai-tan Strait. Further, the data and results of this study will help us to improve efficiency for controlling HAB. Even, it is worthwhile to the management and response to the red tide disaster. Ordination result can also be a good indicator of ecological risk.     

Nitrogen and phosphate removal by free and immobilised cells of Scenedesmus bijugatus (Kützing) from the Pinang River estuary,Penang, Malaysia

This research studied the effects of inorganic nutrient removal by free and immobilized Scenedesmus bijugatus cells, measured by algal growth (i.e., the chlorophyll a concentration) and the efficiency of the uptake of inorganic nutrients by the cells (uptake rate (b) and removal percentage) in water samples from the organically polluted Pinang River estuary (PRE). Water samples from the PRE were collected during low and high tide. S. bijugatus cells had a higher growth rate when incubated in low tide PRE water samples compared to high tide PRE water samples, with a growth rate of 0.29 µgml^?1d^?1 and 0.06 µgml^?1d^?1 for free and immobilized cells, respectively. S. bijugatus was able to more efficiently remove nitrogen, especially ammonium (81–94%), compared to phosphate (62–88%) from both low and high tide water samples. S. bijugatus cells in low tide PRE water samples recorded highest phosphate (0.36 mgL^?1d^?1 and 0.25 mgL^?1d^?1 for free and immobilized cells, respectively) and ammonium uptake rates (0.44 mgL^?1d^?1 and 0.29 mgL^?1d^?1 for free and immobilized cells respectively). Both inorganic nutrient removal and microalgal cell growth were not significantly different between free and immobilized S. bijugatus (p > 0.05). The data obtained indicated that the removal of nutrients by microalgae was affected by salinity and the immobilization technique applied may have good potential for bioremediation.     

黄渤海海水养殖自身污染的评估

探讨了投饵和非投饵两种养殖方式自身污染对海洋环境的影响.结果表明,海水养殖产量与营养盐类、COD和赤潮发生次数均呈正相关关系,其中无机氮含量和赤潮发生次数与虾养殖产量有显著正相关关系,说明海水养殖自身污染对邻近海域富营养化及赤潮发生有一定影响.通过黄渤海海水养殖向海洋排泄氮、磷、COD等污染物估算,分别占相应陆源污染物排海量的2.8%、5.3%、1.8%.虽然与人类其他活动向海洋排污量相比,水产养殖的排污量所占比重还不算大,对于某些局部水域,特别是海水养殖密集区,将对海洋环境的影响产生叠加作用,很可能成为刺激近海富营养化和赤潮发生的一个重要因素,应引起足够的重视.     

Preliminary studies on eutrophication and red tide problems in Bohai Bay

A study was carried out in 1978–1981 on the relationship between eutrophication and the occurrence of red tides in Bohai Bay.An assessment method using a single parameter as well as the multiparameter Trophic State Index was adopted. DIN, DIP, COD loadings and concentrations and phytoplankton community (species composition, diversity index, standing crop, chlorophyll a and primary productivity) were used as parameters. The western part of the bay and two sewage outfall sites showed the highest values of chlorophyll a, nitrate, phosphate, standing crop, primary productivity and the greatest population instability. Therefore, Bohai Bay, can be regarded as mesotrophic, but its estuary eutrophic. Anthropogenic factors are mainly responsible for its eutrophication. A relationship between environmental factors and red tide species was found. Noctiluca miliaris, Prorocentrum minimum and Skeletonema costatum have their bloom periods from July to September and are the most significant species.     

围隔生态系内浮游植物对富磷的响应

在长江口外应用围隔生态系实验方法,研究了富磷与浮游植物生物量的相关性以及浮游植物对磷吸收的种间竞争。结果表明,可溶性磷(主要是PO     

The Nutrient Status of Mgazana,a Warm Temperate Mangrove Estuary in the Transkei,Eastern Cape,South Africa

Mgazana, a rural southern African mangrove system, was visited monthly from August, 1995 to February, 1997 to collect water samples for nutrient analysis. Surface and bottom samples were taken during spring low tide at seven stations along the estuary and the following physico-chemical parameters measured: river flow, temperature, salinity, oxygen, transparency, ammonia, nitrite, nitrate, phosphate, inorganic carbon (IC), organic carbon (OC), total carbon (TC), soluble nitrogen (SN), particulate nitrogen (PN) and total nitrogen (TN). Using correlation matrix analysis and ANOVA, river flow was found to affect estuarine salinity, transparency and stratification, which influenced nutrient dynamics. Significant seasonal (winter and summer) differences were found for temperature, river flow, nitrate, SN, TN, IC and OC. Most nutrients were significantly correlated with river flow showing gradients down the estuary, indicating allochthonous input from the catchment. OC levels within the estuary were high, probably due to autochthonous mangrove leaf-fall processing by the various in-fauna, but high levels measured at the head of the estuary during high river flow suggested additional allochthonous input from coastal forest litter. Conversely, IC was negatively correlated with river flow suggesting that autochthonous faunal and microbial mineralisation of organic matter occurs within creeks, which is then diluted by increased stream-flow. An N:P ratio of 2.7:1 was obtained for this rural mangrove system, which was low compared with Spartina-based East Cape estuaries subject to urban, industrial and agricultural pollution.     

Meiobenthos of hypersaline tropical mangrove sediment in relation to spring tide inundation

Tropical intertidal sediments often contain porewater of relatively high salinity, especially in areas exposed to longer periods without seawater inundation and high evaporation. Such an area exists on the west coast of Zanzibar: a high intertidal mangrove plateau, flooded only during spring high tides, with sediment porewater salinities commonly exceeding 100 ppt. A field survey was conducted in this area to examine variations in population density of major meiofaunal taxa and the assemblage structure of free-living marine nematodes during spring-neap tidal cycles. Samples were taken on seven occasions for two months, starting from the end of the rainy season. Porewater salinity remained high throughout the sampling period, ranging from 89 to 160 ppt. Neither spring tide inundation nor heavy rains lowered the salinity markedly. The meiofauna consisted only of four taxa, present on all sampling occasions: nematodes, harpacticoid copepods, plathyhelminthes and chironomids. Densities in surface sediments (0–5 cm) were low compared to other mangrove areas, ranging from 271 to 656 animals 10 cm^-2 with nematodes dominant on all sampling occasions (58–87%). Density fluctuations could not be explained by the effects of spring tide inundation, but the meiofauna showed significant correlations with grain size and organic material. Despite the wide range of salinity, only the numbers of chironomids were negatively correlated with increased salinity. Nematode species diversity was low in all samples, although altogether 28 species were recorded in the samples. Four species occurred in more than 50% of the samples (Microlaimus sp. (100%), Metalinhomoeus sp. (76%), Daptonema sp.l (56%), Chromadorina sp. (56%)) while 12 species were found only in one or two samples. Multidimensional scaling ordination (MDS) of the nematode species abundance data indicated little effects of spring tide inundation on the assemblage structure, but rather a successive change from wet to dry season with a reduction in species diversity and increased numbers of the dominant nematode species Microlaimus sp.