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1.
海河口位于渤海湾西端,天津市东侧,是仅次于黄河口的渤海第二大河口。渤海湾是一个半封闭性的内湾,水质肥沃,资源丰富,是我国黄海、渤海许多经济鱼、虾类良好的产卵、索饵和育肥场所,在渔业上占有重要地位。自古就有“渔盐之利,舟辑之便”的海河口区,由于其独特的地理位置,对天津市社会经济的繁荣发展起着重要的作用。近20年来,随着天津市工农业的发展和经济开发的加强,以及城市的扩大和人口的密集,人类的社会经济活动对海河口区生态环境的影响越来越大,出现了入海径流锐减,水域污染严重等环境问题,渔业资源受到了威胁。为此,中国科学院海洋研究所与其他单位组成协作组,于1978-1981年对渤海湾的污染状况及其影响进行了多学科的综合调查,结果表明:污染的主要区域是河口近岸区,主要污染物是有机物、氮、磷和石油等。(本集邹景忠、张景镛?文)当时由于受调查范围和项目的限制,对河口区的有机污染研究甚少。为进一步查明海河口区有机污染的状况、规律及其影响,研究河口的物理自净,探索污染防治措施,我们又于1983-1985年,从陆、海区域水环境的综合研究出发,运用环境地球化学和污染生态学的一些理论和方法,比较全面、系统地对面积814 km2 的海河口区进行了多学科的专题调查和室内模拟实验研究。 调查范围是118°E以西,38°35’N以北,水深l0m以浅的外河口(包括大沽口、北塘口及其口外近岸水域)和受潮汐影响的内河口(包括永定新河河口段和大沽排污口),共29个测站(图1)。调查时间为1984年5月(枯水期)、8月(丰水期)、10月(平水期)三个代表月份。8月还在B, D, 8, 17 和20号站进行周日连续观测。调查项目如下: 水文、气象、物理部分:水深、水温、水色、透明度、盐度、海流、风速、风向。 水质部分:溶解氧(DO)、化学耗氧量(COD)、五日生化耗氧量(BOD5)、总氮(TN)、氨氮(NH4-N)、亚硝酸氮( NO2-N)、硝酸氮(NO3-N )、无机氮(TIN)、有机氮(TON)、总磷(TP)、无机磷(TIP)、有机磷(TOP)、阴离子表面活性剂(AS)、悬浮体。 底质部分:有机碳(TOC)、有机氮(TON)、硫化物(S)、腐殖酸(HA)、烧失量(IL)、AS。 生物部分:大肠菌群(CB)、陆源异养菌(THB)、海洋异养菌(MHB)、叶绿素a、浮游动、植物。另外,还进行了天津南、北排污河污水对鱼、虾的急性致毒和鱼虾的回避实验。 本调查是国内首次对河口区有机污染进行综合的研究。通过调查研究,获得了大量数据和样品,经过资料处理、分析和研究,查明了目前海河口区的有机污染水平;探讨了有机污染物的时空分布特征和迁移、转化规律;阐明了有机污染对河口生物(微生物、浮游生物、经济鱼虾)的影响状况;计算了海河口和渤海湾的三维潮流场,建立了COD的三维扩散数值模拟;并在此基础上提出了污染防治对策和建议。其中,对某些有机污染物的迁移、转化规律和河口生态现象所提出的一些新见解,以及调查中所建立的综合研究方法、有机污染评价方法和阴离子表面活性剂分析方法等等,对当前和今后更深入地研究有机污染规律及防治措施都有一定参考价值。 本调查研究成果包括调查报告和专题论文两部分。本调查报告,着重讨论海河口区水环境特征,海河口区有机污染的评价和海河口区有机污染的防治途径等三项内容。  相似文献   

2.
渤海湾海河口区是北京、天津二大城市工业及生活污水排放入海处,是一比较典型的海域。1972年以来曾对渤海湾进行过综合性的环境污染调查和研究,但由于受调查范围和项目的限制,对河口区特别是大沽口、北塘口区有机污染物的迁移转化研究甚少,尚不足以就有机污染对河口生态环境的潜在影响作出科学判断。目前,有机污染已成为海河口区特别是其附近大城市的主要污染问题之一。本文以化学耗氧量(COD)、生物耗氧量(BOD5)、溶解氧(DO)等项目作为耗氧有机物污染程度评价的主要指标(还有氮、磷、本集另有专文讨论),对海河口区有机污染物的迁移、转化及生态效应进行了调查研究,为有机污染评价提供数据并作初步探讨。  相似文献   

3.
河口区海域是河川径流与海水交汇混合的地带,水环境各要素的变化相当复杂,构成了一个特殊的生态系统。 河口水的盐度因径流量的变化和潮汐的作用而具明显的季节变化和日变化。丰富的有机碎屑和各种营养物质随着河川径流不断地汇入河口水域,为浮游生物的大量繁殖提供了有利条件,使河口海域成为不同营养级生物生产过程极其强盛的区域;同时,大量有机碎屑和生物尸体的存在也使得河口海域微生物的生命活动异常活跃。 然而另一方面,随着近代工业的发展,城市规模的扩大,注入河口水域的工业废水和生活污水不断增多,对河口生态系统形成了与日俱增的威胁和冲击。海河口区就是其中比较突出的一个。 尽管近年来,对区域性海洋异养细菌的生态分布的调查研究国内外已有不少报道(陈騳、钱振儒等, 1982 ;张景镛、李士荣等, 1984; Ishida, Y. & H. Kadota,. 1974; Austin, B.& S. Garges et al., 1979; Simida, U., N. Taga et al., 1980; Sugita, H., H. Tanami et al., 1981; Simida, U., K. Tsukamoto et al., 1982; Sugahara, L, L. C. Lim et al., 1984),但是有关河口水域海洋异养细菌的生态分布及其菌群组成特点的调查研究报告,在国内则尚未见到。 调查了解海河口区有机污染水域中海洋异养细菌的分布规律和菌群的组成特点,不仅有助于阐明富营养化与海洋微生物间的关系,而且对于河口生态系统的深人研究也是有意义的。  相似文献   

4.
河水径流是海洋营养盐最重要的来源之一。河流排放的营养盐为河口海区自养生物的繁殖提供了重要保证,但是过量的营养盐反会引起海水污染和水域富营养化,从而危及海洋生物的生命活动。研究河口及其附近海域营养盐的分布变化,不仅对了解它们在河水-海水界面的转移规律,而且对河口生态学的研究均具有重要意义,因此日益受到重视(顾宏堪等,1981;王正芳等,1983;林植青等,1984;吕小乔等,1985;沈志良等,1987)。 本文主要对黄河口及其附近海区水中硝酸盐、亚硝酸盐、氨氮和磷酸盐的分布特征、在河口的转移过程以及它们与浮游植物的关系等进行一些探讨。  相似文献   

5.
目前海洋污染以沿海工业大城市附近的港湾、河口区以及浅水海区较为显著。作者通过对渤海湾河口区污染状况的调查,研究了有机污染要素磷在海河口区的分布特征及其迁移规律,进而探讨磷在河口区有机污染中所起的作用以及与其他污染指标项目之间的关系。  相似文献   

6.
Okamoto (1969)指出,多变量的主成分具有变差最优性、信息损失最小性、相关最忧性和回归最优性等最优性质,因此多变量的主成分分析被广泛应用于自然科学和社会科学多种领域。由于主成分可以看作所研究的某个复杂事物的一个概括(肯德尔,1975),并可根据主成分所提供的数据,按数值大小排列顺序分级,因此主成分分析也被遥感界应用于区分不同水质(Klemas et al, 1981)。 本文以渤海湾西北部海河、永定新河河口区的陆地卫星数据作主成分分析,以显示河口区海水不同污染等级。同时以河口区各站位实测的多项有机污染数据作主成分变换,按主成分数值大小,将各站位分为不同污染等级。计算表明,遥感数据显示的不同污染等级的地理分布与实测数据是一致的。  相似文献   

7.
对于氮在河口区、海湾、大洋中的分布,氮的迁移,以及氮的地球化学,国内外己作过大量研究(Cooper, 1937; Brand, 1937-42 ;顾宏堪等,1981, 1982 )。本文主要从环境化学的角度了解渤海湾海河口区氮的分布规律,探讨各态氮从河口区入海后的变化、迁移和转化过程,为研究海洋中氮的迁移提供依据,也为氮的含量变化以及富营养化程度对河口区生物及水产资源的影响提供必要数据。  相似文献   

8.
三角褐指藻细胞密度对累积和排出 65Zn的影响   总被引:1,自引:0,他引:1  
本所在渤海湾污染调查中发现河口区沉积物已受到不同程度的重金属污染,如Zn在大沽河口外表层底质中的浓度已达131.5ppm~1)远高于本底值(70ppm)。渤海湾由于水质肥沃、饵料丰富,因而是我国北方海区的重要渔场之一。为研究近海河口区饵料细胞密度与污染物  相似文献   

9.
河口海区是浮游生物大量繁殖孳生的水域,也是许多水产动物的产卵、索饵场。渤海湾历来盛产食用贝类,又是某些经济鱼、虾类的天然渔场。但近十多年来,渤海西部主要鱼、贝类的产量逐年下降;探讨其原因时必然会考虑渤海湾的陆源污染是否已经危及饵料基础,从而导致渔业资源的衰退。本文试图通过查明渤海湾浮游动物生态现状,揭示陆源污染对其产生的影响,为评估渤海湾环境质量和采取渔业环境保护措施提供一个方面的科学依据。  相似文献   

10.
为考察长江三峡工程对河口区生态环境的影响,有必要探讨长江径流量的季节变化对河口区及口外陆架区流场结构的影响。在“长江三峡工程对长江口区流场的影响”的一文(本集)中,作者己着重探讨了三峡工程的流量调节方案将给长江口区流场带来的可能影响。本文试图从长江径流量的季节变化来分析长江口外陆架海域海流结构的季节变化,从而为三峡工程流量调节方案的设计提供某些依据。 关于长江口区及其邻近陆架海域的海流结构问题,根据实测海流资料所作的分析,迄今为止,主要限于洪水季节(即夏季)(乐肯堂,1987,1986,1984;赵保仁,1982;上海航道局设计研究所,1978;中国科学院海洋研究所,1977;华东师范大学地理系河口海岸研究室,1975,1973; Le Kentang,1986;Cannon, et al. , 1983; Beardsley et al.,1983)。长江口区枯水季节(冬季)的海流结构曾已讨论(Le Kentang, 1988)。至于春、秋两季,迄今尚未见有专题论述。本文将根据已收集到的实测余流资料(其中包括1959-1976年的资料,1980-1981年间的中美联合考察资料和1985-1986年的专题调查资料),结合有关的水文观测资料,对本区各个季节余流的结构作一初步的分析。  相似文献   

11.
The distribution and feeding of dominant mesozooplankton species were studied in the estuary of the Ob River and adjacent inner Kara Sea shelf waters in September 2013. It was shown that the spatial distributions of Cyclops sp., Senecella siberica, Limnocalanus macrurus, Mysis oculata, Drepanopus bungei, Jashnovia tolli and Pseudocalanus sp. are related to the specific characteristics of the hydrographic regime in the estuarine frontal zone. The distributions of Cyclops sp., Senecella siberica, and Pseudocalanus sp. are mainly limited by salinity, while other species inhabit an area with a wide range of salinity values without clear preferences. Peaks of their abundance could be either consolidated or distanced in space. The populations of Jashnovia tolli, Drepanopus bungei, and Pseudocalanus sp. permanently inhabit the layer under the pycnohalocline; the populations of Cyclops sp. and Mysis oculata inhabit the upper mixed layer. Limnocalanus macrurus demonstrates a different vertical distribution pattern: the copepod undertakes diel vertical migrations in the southern part of the estuarine frontal zone; in its northern part, the population is concentrated below the pycnocline during day and night. The differences in the distributions of the studied species determine their feeding behavior and their role in phytoplankton grazing. The most intense utilization of biomass and production of autotrophic phytoplankton by zooplankton occur in the freshened water zone and the adjacent southern periphery of the estuarine frontal zone: the total daily phytoplankton consumption makes up 10–18% of the biomass and 60–380% of primary production. Daily zooplankton consumption of phytoplankton in the estuarine frontal zone decreases to 2–7% of the biomass and to 14% of primary production; in inner shelf waters, the values do not exceed 1% for both phytoplankton biomass and production.  相似文献   

12.
长江口区浮游植物的数量变动及生态分析   总被引:1,自引:0,他引:1  
长江口一带水系交汇复杂,海水理化环境多变,导致海洋生物资源量产生很大波动。预计在三峽水利枢工程建成调节入海径流量后,河口生态环境必将出现新的格局,对河口生态系、生物资源量和社会经济将产生很大影响。故在工程兴建前必须从多方面进行预测和研究,以便对工程作出科学评价。以往虽在河口附近进行过多次调查,但迄今仍缺长江口门水域及河道内的资料,难以全面说明径流对河口环境的影响。为此,在1985-1986年逐月进行了长江口区生态环境及生物资源的本底调查。本文旨在根据调查结果探讨工程建成后,对作为生态系基础环节的浮游植物可能产生的影响,并为河口区生物资源开发利用提供科学依据。  相似文献   

13.
The studies were carried out on September 27–30, 2007, in the area of the Ob estuarine frontal zone and over the adjacent inner Kara Sea shelf. Based upon the latitudinal changes in the salinity, the 100 nautical mile wide estuarine frontal zone was marked out. The frontal zone was inhabited by a specific zooplankton community dominated by species that occurred outside the frontal zone in only minor amounts. The biomass of the mesozooplankton averaging 984 mg/m3 in the frontal zone exceeded by 1.5 and 6 times the corresponding values in the inner desalinated area of the estuary and the adjacent areas of the Kara Sea shelf. At the inner southern periphery of the frontal zone, at maximal latitudinal salinity gradients (>2 psu per mile), the maximal development of the mesoplankton with the mean biomass for the water column of 3.1 g/m3 (37 g/m2) and up to 5.8 g/m3 in the subpycnocline layer was observed. The latitudinal extension of the biomass in the maximum zone did not exceed 10 miles. More than 90% of the maximum was composed of herbivorous zooplankton with the strong domination of the copepod Limnocalanus macrurus. The daily consumption within the zooplankton maximum area was estimated at 820 mgC/m2 per day. This value exceeds by two orders of magnitude the local primary production. At that level of consumption, the available phytoplankton biomass was consumed by grazers in less than 8 hours (!). A zooplankton aggregation at the southern periphery of the estuarine front exists due to the advection of phytoplankton from the adjacent river zone. The aggregation forms a natural pelagic biofilter where new allochthonous organic matter delivered by the river flow is accumulated and high secondary production is formed on its basis. An anomalously high concentration of planktic predatory Parasagitta elegans with biomass of over 1 g/m3 (46% of the total zooplankton biomass) was associated with the outer northern periphery of the estuarine frontal zone.  相似文献   

14.
渤海湾水质肥沃,生物资源丰富。但近些年来每年注人海湾的污水殊为可观,对近岸水域造成很大威胁。为此,1978-1982年由中国科学院海洋研究所和天津市环境保护监测站、南开大学等单位组成的协作组,对渤海湾进行了多学科、综合性的环境污染调查和研究,本文是其部分成果的综述。  相似文献   

15.
2004-2016年夏季长江口网采浮游植物及其影响因素   总被引:1,自引:0,他引:1  
基于2004-2016年夏季长江口生态监控区13年的生态环境调查数据,开展网采浮游植物年际变化及其与环境因子关系研究。结果表明:(1)共鉴定出浮游植物7门263种,以硅藻占绝对优势,甲藻次之,物种数呈增加趋势,其中硅藻种类数占有比下降,而甲藻的种类数占有比呈上升趋势;(2)总细胞丰度、硅藻细胞丰度和甲藻细胞丰度都呈上升趋势,除2014年外,其余年份硅藻细胞丰度都占绝对优势并与总细胞丰度的分布曲线和变化趋势基本一致;(3)水平分布模式及其年际变化受环流变化和水团消长的影响,总体趋势是河口区细胞丰度较低,由河口到外海呈逐渐增大趋势,部分年份呈现先增大后减小的趋势;(4)生物多样性多年呈下降趋势,物种组成随空间和时间变化较大,只有较少的种类能够保持稳定,多数物种只是偶尔被检出;(5)中肋骨条藻有10年为区域第一优势种,41种常见种中有31种细胞丰度呈增加趋势,10种细胞丰度呈下降趋势。(6)浮游植物细胞丰度与活性磷酸盐和无机氮具有相关性,种类数、多样性指数除了与溶解氧、氨氮、叶绿素a无相关性外与其他10种环境因子都相关。本研究能够较好反映研究区域浮游植物的本底情况及演变趋势。  相似文献   

16.
The phytoplankton ecology of Great South Bay, New York, was studied over a 1-year period. The study area, a large barrier island estuary (coastal lagoon with estuarine circulation), was characterized by high levels of inorganic nutrients, high turbidity and a shallow euphotic zone (<2 m). Net annual primary production by phytoplankton was high—450 g C m?2 year?1—and accounted for approximately 85% of the total ecosystem primary production. Chlorophyll a-specific productivity was dependent on mean photic zone light intensity in areas of the bay <1 m in depth from September 1979 through June 1980; 65–95% of the total light extinction in those areas was attibutable to suspended solids. Nitrogenous nutrient concentration did not limit phytoplankton productivity. Diatom and dinoflagellate cell densities varied greatly over time, while cryptomonad and chlorophyte species were abundant throughtout the year. Chlorophytes of 2–4 μm (‘small forms’) were numerically dominant, and contributed approximately half of the total phytoplankton biomass. Dilution of bay water by intruding ocean water appeared to control the spatial distribution of chlorophyll a on the south side of the bay; in other areas, growth appeared to exceed the rate of dilution by flushing. Waters entrained in eelgrass beds were significantly higher in salinity and mean photic zone light intensity, and had lower phytoplankton standing stock and depth-integrated primary production than control areas; waters in the sediment plume of active clamdigging boats were statistically similar to control areas with respect to water quality and phytoplankton community characteristics.  相似文献   

17.
于2010年8月和10月对厦门海域营养盐和浮游植物等开展了两个航次的调查,目的在于研究该海域营养盐含量和比率变化及其对水采浮游植物群落的影响.各化学和生物要素的采集、保存和分析按照《海洋调查规范》或《海洋监测规范》的相关方法进行.研究结果表明,厦门海域浮游植物生长的营养盐限制性因子与1998年的研究结果比较,依然为PO4-P,而SiO3-Si含量和DIN含量相对充足.各项营养盐含量与盐度都有较明显的负相关性,其中保守性最明显的是DIN,而PO4-P与盐度的相关性相对最低.此外,8月份鉴定到的甲藻门种类和生物量明显高于10月份.本文认为,目前厦门海域营养盐比率变化的主要压力为N/P摩尔比率失衡.随着人为输入氮源的增加,在富氮的九龙江口及其邻近海域,极易发生中肋骨条藻赤潮,该藻的生物量与NO3-N和SiO3-Si含量的相关性十分明显.研究发现,厦门甲藻/硅藻生物量的比值与NO3-N和N/P摩尔比率有一定的正相关性,可能预示着该海域无机氮含量的增加及其引起的N/P摩尔比率增大会促进甲藻门种类的生长.并且浮游植物Shannon生物多样性指数可作为反映厦门海域富营养化较好的生物指标.  相似文献   

18.
The data for the present study were collected at 20 sampling stations in the Kara Sea along the transect from the Ob estuary to the deep sea St. Anna Trough in September 2007. Based on the hydrophysical features, the distribution of the Chl a, and the primary production, we distinguished six habitats: the river, estuary, inner and outer shelf, continental slope, and trough. The impact of the small-size (<0.5 mm) and large-size (>0.5 mm) fractions of the zooplankton on the phytoplankton’s organic carbon in the different regions of the Kara Sea was estimated. The ingestion rate was assessed using the analysis of the gut fluorescence content and the gut evacuation rate. The zooplankton grazed 1–2% of the phytoplankton biomass in the river and estuary; 3.5% over the shelf; and 6 and 10% in the regions of the trough and slope, respectively. The grazing impact of the small-sized zooplankton increased from the river zone to the deep regions (from 1 to 90%) along with their share in the total zooplankton abundance (from 18 to 95%). From 72 to 86% of the primary production was grazed over the shelf and slope. The primary production did not cover the feeding requirements of the zooplankton in the estuarine regions and St. Anna Trough in the autumn. In the estuarine regions, the major portion of the organic matter settles on the bottom due to the strong inflow of the allochthonous matter and the relatively low zooplankton grazing.  相似文献   

19.
河口是咸淡水交汇的水域,有大量的营养物质,是初级生产力和浮游生物最丰富的水域,为鱼类及其幼鱼的生长提供了丰富的饵料基础。本文综述了国内外有关河口鱼类早期资源(鱼类浮游生物)生态学研究的若干最新研究进展,内容包括:河口鱼类浮游生物的生态类型、种类组成和时空分布,温度、盐度、混浊度、食物、其他动物捕食等环境要素,厄尔尼诺和拉妮娜现象等气候现象,和大型工程建设、过度捕捞和污染等人为因素对河口鱼类浮游生物群落结构影响的研究。  相似文献   

20.
Phytoplankton diversity and community composition were studied along the Schelde river–estuary–coastal zone continuum during the summer of 2003. DCA analysis indicated a gradual compositional turnover of the phytoplankton community within the estuary. GAM modelling of species response curves along the estuarine gradient was used to identify taxa that had their population maximum in the river, the coastal zone or within the estuary. Taxa that had their population maximum within the estuary did not form a homogenous community but comprised species with different salinity optima and rather restricted salinity tolerances. The observed changes in community composition along the estuarine transition zone correspond more closely to an ecocline than to an ecotone model. Despite the fact that few taxa had their population maximum at or near the salinity gradient, alpha diversity did not display a minimum around the salinity gradient. This lack of a diversity minimum within the estuary was ascribed to an important contribution of taxa of riverine or coastal origin to alpha diversity within the estuary contributed. On average 55% of the alpha diversity in the estuarine samples was due to riverine or coastal taxa. Beta diversity displayed a clear maximum around the salinity gradient. For planktonic organisms which are subject to mass effects, beta diversity is probably a better indicator for the impact of the salinity gradient on diversity in estuaries than alpha diversity.  相似文献   

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