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自1971年围垦后，厦门港成为内湖，没有海水进出交换，从而积蓄多种有机污染物和重金属。但自从1984年采取纳潮排污后，该湖水质有所改善。本研究于1999年主要对湖水质进行调查和评价。结果显示污染物含量虽然有所降低，但仍属于污染状态。其纳潮排污，每天可排放出：石油烃40.8kg，有机氯农药0.011kg，铜4.54kg,铅0.284kg，锌11.97kg，镉0.36kg，汞0.011kg。由于湖水水质仍未完全改善，非常有必要继续进行监测。 相似文献
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根据2011-2013年福建省长乐市金峰镇陈塘港排污口及其邻近海域监测数据,对该排污口污染物状况及其对邻近海域环境的影响进行了研究。结果表明,排污口排放污水的主要污染物为化学需氧量、硫化物、悬浮物、生化需氧量和氨氮,化学需氧量超标明显且污染加剧;排污口邻近海域水质主要超标污染物为无机氮、悬浮物和活性磷酸盐,化学需氧量、石油类和重金属铅、铜、锌也有不同程度超标,综合评价结果显示水环境处于严重污染状态,海水水质等级为劣四类,无机氮和活性磷酸盐超标最为突出;海域表层沉积物超标污染物为重金属铅、锌和铜。该海域水质和沉积物超标污染物与陆源排污及闽江径流携带物质有关。 相似文献
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污水排入湖泊后,受污染的水体,由于各种物理、化学和生物等因素的作用,污染物浓度逐渐降低,经过一段时间后恢复到受污染前的状态,这一现象称为水体自净,研究污水入湖自净规律是开展湖泊水质预报,合理制订入湖污染物排放标准的依据。含酚污水是世界上污染范围较广,危害程度较大的一种工业废水,但是,有关含酚污水入湖自净规律的研究资料,目前尚为不足。本文试图根据二年多现场观测和室内实验资料,对造成太湖局部水域污染的某造纸厂含酚污水入湖后的沿程变化规律,作一初步探讨。 相似文献
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闽江下游河道排污口设置的水质响应分析 总被引：1，自引：0，他引：1
建立了闽江下游河道一维动态水质模型，探讨了北港不同排污口设置方案对南、北港分汉河道水质的影响．结果表明，北港排污不仅影响排污口附近及北港河道的水质，还影响到南港河道；两个排污口组合设置下的水质好于单个污染源设置情况：污染物浓度过程呈现周期性的变化，排污口河段以上断面，涨潮时污染物浓度增高，落潮时污染物浓度降低，排污口河段以下断面的则相反 相似文献
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本文应用二维水质数学模型,分析了舟山水产食品厂排污对沈家门港区水质影响的现状,并预估了新、老两厂同时运行后港区水质污染的程度。 计算结果表明,沈家门港内污染物质主要靠潮流的稀释和输移。在此狭长的水道内,水流沿纵向流动,横向水体交换少,以致污染物沿横向不易弥散。污水沿岸排放后,高浓度污染带紧贴岸边随涨落潮流往复移动,对水道内水质有一定影响。 相似文献
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随着沿海地区社会经济的快速发展,化学污染物的排海数量不断增加,海水水质不断恶化,我国的海域自北到南已遭到不同程度的污染和破坏,一些港湾、河口、近海海域污染已相当严重。实施污染物排海总量控制是改善海洋环境质量的重要措施。文章从法律、行政法规、部门法规、地方法规和规章以及相关标准和技术规范等5个层面对我国海域排污总量控制制度建设框架进行了设计;提出海域排污总量控制条例作为海域排污总量控制制度的主要组成部分,应包括总则、规划编制与管理、排污许可与排污交易、排污核查与监督以及法律责任等方面;根据我国对海域排污总量控制制度的必要性和急迫性,从加快立法、建立配套制度和强化管理等方面对海域排污总量控制制度提出建议,为我国海域排污总量控制制度建设提供科学依据。 相似文献
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依亚瓦拉半封闭澙湖是澳大利亚西南侧最著名的海岸澙湖,是全新世海侵以来残留的濒危脆弱地貌。湖面约35km2,流域面积达270km2,长期沉积速率不足1mm/a,短期沉积速率约5~6mm/a。近几十年来,由于受陆源泥沙淤积和工矿重金属污染,澙湖正处于快速退化阶段。当局采取以疏为主的多项整治措施,隔绝陆沙入湖、浚深湖底、加固湖岸、杜绝圈湖养殖、扩宽潮道,缩短了海、湖水交换的时间,目前已变成湖水清澈、鱼虾洄游的旅游圣地。该整治经验可为我国海岸澙湖研究提供借鉴。 相似文献
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为研究莱州湾水交换对胶莱运河修建工程的响应,以及为海洋污染治理问题提供参考,以莱州湾为重点模拟区域建立了二维平面潮流和对流扩散模型,利用渤海、黄海、莱州湾地形及海洋环境资料,结合2018年莱州湾海水水质监测结果,初步分析了胶莱运河的修建对莱州湾海洋环境现状的影响。模拟结果表明,胶莱运河建成后年径流总量约为7.2×109 m3,净流方向由胶州湾流向莱州湾;工程后整个莱州湾水交换能力略有增强,东部强于西部,半交换周期缩短14 d;黄海海水经由胶州湾进入胶莱运河输送至莱州湾,冲淡莱州湾内非优良水体,从一定程度上缓解了莱州湾东部河口入海处小范围海域海水水质现状。 相似文献
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The lake Hunnebotn (A=1 km2, zmax=11 m) has become separated from the sea by isostasis, but a 1.5-m-deep channel is held open by periodic dredging. Water exchange is minor due to the small tidal range (21 cm) and the length of the channel (1.8 km), but there may be an inflow of seawater at spring tides. The terrestrial watershed runoff may be fertilized by sewage and agricultural runoff despite some measures taken to prevent this. Historical and new records of biological communities indicate variations in sensitivity to different phases of the isolation and eutrophication process. The native oyster was most sensitive and disappeared first. Later, the eelgrass disappeared possibly due to overgrowth by epiphytic algae, and finally there was a massive littoral–sublittoral invasion of green algae. The lake should not be left in this condition, for aesthetic reasons and because marine inlets and eutrophic brackish water may serve as refugia for spore populations of toxic microalgae. Improving surface water quality will require better control of anthropogenic sources, but bursts and leaks of nutrients from the anoxic monimolimnion cannot be controlled. 相似文献
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A three-dimensional （3-D） finite volume coastal ocean model （FVCOM） was used for the study of water cir culation and seawater exchange in the Benoa Bay, Bali Island. The M2 tidal component was forced in open boundary and discharge from six rivers was included in the numerical calculation. The M2 tidal elevation produced by the FVCOM has a good agreement with the observation data. The M2 tidal current is also suc cessfully calculated under the ebb tide and flood tide conditions. The non-linear M2 tidal residual current was produced by the coastline geometry, especially surrounding the narrow strait between the Serangan Is- land and the Benoa Peninsula. The tidal residual current also generated two small eddies within the bay and one small eddy in the bay mouth. The salinity distribution influenced by river discharge could be success- fully calculated, where the numerical calculation and the observation results have a good correlation （r2） of 0.75. Finally in order to examine the seawater exchange in the Benoa Bay, the Lagrangian particle tracking method and calculation of residence time are applied. The mechanism of particle transport to the flushing of seawater is depicted clearly by both methods. 相似文献
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修建海岸水库是满足滨海地区淡水资源的保障的一个重要方式,为了进一步分析海岸水库的建立对滨海含水层的海水入侵的影响,采用SUTRA(saturated-unsaturatedtransport)模型建立具有代表性的二维海岸模型开展定量和定性研究,结果表明:潮汐作用抑制底层盐水楔的入侵,加快海陆物质交换;实例中计算表明建坝后,海岸水库坝体的建立加剧了海水入侵;水库水位在平均海平面以下时,潮汐动力因素占主导,海水入侵严重且随着水位抬高,海水入侵程度基本保持不变,应注意海水入侵的防治;库区水位在平均海平面以上时,海水入侵程度随着库区水位的抬高而减少,可以调节水库水位进行滨海含水层的海水入侵的防控;海岸水库在建设中存在一个控制水位,当水库水位在控制水位以上,库区水体盐度和含水层淡水储量能得到保证;库区高水位时内陆物质运移时间较长,运移区域较广,氮类污染物易在库底含水层堆积,需重视含水层的地下水污染防治。 相似文献
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文章利用2017—2019年杭州湾海域12个航次的水质监测资料，分析水质调查项目中石油类的分布特征。研究结果表明：2017—2019年杭州湾海域水质石油类含量范围分别为0.008～0.042 mg/L、0.011～0.046 mg/L、0.007～0.094 mg/L,年度平均含量分别为0.023 mg/L、0.023 mg/L和0.016 mg/L,均满足第一类海水水质标准。在季节变化上，水质中石油类指标由于受潮流、含沙量及风力等物理因素影响表现不明显，均属于低含量下的波动。在年际变化上，2017年和2018年石油类含量总体相当，2019年相比前2年有显著降低，具有一定的下降趋势。在平面分布上，主要呈现为多点源分布，高值区主要出现在嘉兴近岸和杭州湾南岸。通过相关性分析研究发现，石油类含量与悬浮物呈显著负相关，海水中悬浮物对石油类污染物有吸附作用，海水中悬浮物的质量越大，石油类含量越低。 相似文献
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Ivanov V. A. Lyubartseva S. P. Mikhailova É. N. Shapiro N. B. Shteinman B. S. 《Physical Oceanography》2002,12(1):43-53
Within the framework of a one-dimensional model taking into account the presence of an upper mixed layer, we compute the seasonal variation of temperature and the concentration of dissolved oxygen in the central part of Lake Kinneret. The temperature conditions of the lake are determined by heat exchange with the atmosphere, and the oxygen conditions depend on gas exchange with the atmosphere and oxygen consumption in sediments as well as on internal sources and sinks. The latter are connected with oxygen supply in the course of photosynthesis and its consumption for the oxidation of labile organic substance in the water thickness. In the period of winter convection from December to February, when the upper mixed layer reaches the bottom, complete aeration of water takes place. The presence of thermal stratification of the lake in the remaining time results in oxygen deficiency under the thermocline. 相似文献
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罗源湾海水交换三维数值模拟 总被引：5，自引：0，他引：5
利用ECOMSED模式中的示踪粒子三维追踪模块分析罗源湾的水交换情况。结果表明,水交换能力的强弱与纳潮量的大小成正比。这里分析湾内水逗留期的空间分布,然后根据湾水存留期的不同将湾内划分为4个地区。进一步的研究表明不同海区湾水逗留期的差异主要是由欧拉余流场的结构差异造成的。由于风场可以影响当地的海流,因此不同的风场也会影响水交换能力。本文结果表明西南方向的风有利于水交换;而作为罗源湾全年主导风向的东北风,在平均风速的情况下,却阻碍了湾内水体的交换。本文还发现在不同投放时刻水交换能力的不同。初始投放时刻的不同对质点总数的减少速度有较明显的影响,高潮时和落潮中间时投放的质点数要比涨潮中间时和低潮时投放的质点数减少得快。罗源湾水交换能力的垂直分布不是均匀的:表层交换率较快,底层较慢,整个海域的交换能力与中层的相当。 相似文献
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Dae-In Lee Jeong-Min Choi Yeon-Gyu Lee Moon-Ock Lee Won-Chan Lee Jong-Kyu Kim 《Estuarine, Coastal and Shelf Science》2008,80(4):495-508
An eco-hydrodynamic model was used to estimate the carrying capacity of pollutant loads and response of water quality to environmental change in Yeoja Bay, Korea. An energy-system model also was used to simulate the fluctuation in nutrients and organic matter in the bordering wetland. Most water quality factors showed a pulsed pattern, and the concentrations of nutrients and organic matter of seawater increased when input loads of nutrients increased due to freshwater discharge. The well-developed tidal zones and wetlands in the northern area of the bay were highly sensitive to input loads. Residence times of water, chemical oxygen demand (COD), and dissolved inorganic nitrogen (DIN) within the bay were estimated to be about 16 days, 43.2 days, and 50.2 days, respectively. Water quality reacted more sensitively to the effects of nitrogen and phosphorus input than to COD. A plan to reduce the present levels of COD and dissolved inorganic phosphorus (DIP) by 20–30% and DIN by at least 50% in pollutant loads is needed for satisfying the target water quality criteria. The natural removal rate of nutrients in wetlands by reeds was assessed to be approximately 10%. 相似文献