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1.
文章通过钦州湾现场调查资料,分别利用单因子污染指数法和富营养化指数法对湾内水质的污染状况和富营养化水平进行评价,并分析讨论不同的富营养化水平条件下浮游植物叶绿素a的响应。结果显示,钦州湾的污染状况和富营养化程度从湾顶至湾外呈现由重至轻的梯度变化,并出现两个“极端区域”:茅尾海化学需氧量(COD)和营养盐的污染指数劣于三类海水水质标准并重度富营养化;外湾污染指数符合一类海水水质标准并贫营养化。分析表明,茅尾海的重度富营养化是由河流输入、相对封闭的地形以及过度的牡蛎养殖造成,而外湾的贫营养化则主要归因于较少的水产养殖和陆源污水排放以及大量的浮游植物对磷酸盐的消耗。叶绿素a在这两个区域均呈现低值,茅尾海内主要是由于贝类滤食大粒径浮游植物和真光层深度下降引起,而外湾则是氮磷比(N/P)失衡,浮游植物生长受磷限制导致。另外,核电站温排水有可能是导致叶绿素a较高的原因。减少茅尾海内的养殖规模,种植红树林,集中污水于外湾排放,加强温排水口的水质监控是保证钦州湾海洋生态环境可持续发展的手段。  相似文献   
2.
The physico-chemical and bacteriological parameters of the water in Taladanda canal and associated water-borne diseases,from which the dwellers have suffered,were studied,by using statistical method. Overuse and the addition of the wastes with sources from urbane industrial sectors,as well as the decrease in water level have caused the canal water quality declined drastically and subsequently led to extensive eutrophication and bacterial contamination. According to the water sample analytical results,the water is lightly acidic with the pH value of 4.5~6.7. The measured indexes,such as total dissolved solid (TDS),electrical conductivity (EC),total suspended solid (TSS),Mn,Zn,Al,Fe,Cu,Cr,and Hg etc,mostly have very high concentrations which are higher than permissible limit,indicating that the canal water is completely unsuitable for human consumption. Furthermore,the biological analysis shows that the total coliform (TC) is in the range of 45.9~30.2 in per 100 mL water in April,30.5~25.3/100 mL in July and 52.9~35.4/100 mL in December,respectively. Similarly,fecal coliform (FC) ranges from 12.8 to 10.1,10.5~7.5 and 13.1~6.4 per 100 mL water in the months of April,July and December respectively. As a result,people who use the water have suffered from different water-borne diseases. On the basis of disease data derived from hospital observations in a period of three years,there had been 4 284 people affected by different water-borne diseases from 2016 to 2018.  相似文献   
3.
为了探讨广东雷州珍稀海洋生物国家级自然保护区海域水体和沉积物中石油类的含量及其分布特征,文章于2017年和2018年分别对保护区海域的石油类进行了调查。结果表明,保护区表层水体石油类含量为0.003~0.066mg/L,平均含量为0.015mg/L,平均污染指数为0.30,保护区水体中的石油类基本符合一类海水水质标准。保护区表层沉积物中石油类含量为3.0~54.8mg/kg,平均值为11.109mg/kg,符合海洋沉积物第一类质量标准。保护区水体和沉积物中石油类含量的变化规律基本相似,但是沉积物中石油类含量的变化更大。根据调查数据分析,保护区水体中石油类的主要来源是保护区社区小型渔船航行排放的石油类,以及保护区周边渔船在航行过程排放的石油类扩散到保护区海域。  相似文献   
4.
In recent years, several studies focused on the detection of hydrocarbon pollution in the environment using hyperspectral remote sensing. Particularly the indirect detection of hydrocarbon pollution, using vegetation reflectance in the red edge region, has been studied extensively. Bioremediation is one of the methods that can be applied to clean up polluted sites. So far, there have been no studies on monitoring of bioremediation using (hyperspectral) remote sensing. This study evaluates the feasibility of hyperspectral remote sensing for monitoring the effect of bioremediation over time. Benzene leakage at connection points along a pipeline was monitored by comparing the red edge position (REP) in 2005 and 2008 using HyMap airborne hyperspectral images. REP values were normalized in order to enhance local variations caused by a change in benzene concentrations. 11 out of 17 locations were classified correctly as remediated, still polluted, or still clean, with a total accuracy of 65%. When only polluted locations that were remediated were taken into account, the (user's) accuracy was 71%.  相似文献   
5.
In this study,accumulation and distribution of Pb,Cu,Zn,Co,Ni,Mn and Fe in water,bottom sediments and four plant species (Myriophyllum verticillatum,Hydrocharis morsus-ranae,Nymphaea alba and Typha latifolia) were investigated in (C)ernek Lake of Kizihrmak Delta.The Kizdirmak Delta is one of the largest natural wetlands of Turkey and it is protected by the Ramsar convention since 1993.Selected physico-chemical parameters such as pH,conductivity and dissolved oxygen and also trace metal concentrations were monitored in water.All the parameters obtained were found higher than that of the national standards for the protected lakes and reserves.The accumulated amounts of various trace metals in bottom sediments and wetland plants were found in the following order of Fe > Mn > Zn > Ni > Co > Cu > Pb and Fe > Mn > Zn > Ni > Co respectively.The historical trace metal intake of Myriophyllum verticillatum,Hydrocharis morsus-ranae,Typha latifolia and Nymphaea alba were obtained higher than that of the toxic metal levels and these plants may be accepted as accumulators for the detected trace metals and also bioindicators in the historically polluted natural areas.  相似文献   
6.
乌斯河铅锌矿床位于扬子板块西南缘,是川滇黔铅锌矿集区代表性大型铅锌矿床之一,估算资源量超过370万吨,Pb+Zn平均品位~15.7%。该矿床铅锌矿体主要呈层状、似层状、透镜状产于震旦系灯影组的白云岩地层中,其围岩蚀变较弱,以白云石化和方解石化为主。矿石类型主要包括块状、条带状、角砾状、脉状和浸染状等,其中矿物组成相对简单,以闪锌矿、方铅矿、白云石和方解石为主,含少量沥青和黄铁矿。该矿床地质地球化学研究程度相对较低,其成矿物质来源不清,致使该矿床存在热水沉积成因、喷流沉积-后期热液叠加改造以及MVT型等多种成因争议,难以建立统一成矿模式。本文对乌斯河铅锌矿床不同成矿阶段的硫化物(包括黄铁矿、闪锌矿和方铅矿),开展原位硫和铅同位素地球化学研究,以查明该矿床的成矿物质来源、还原硫的形成机制和示踪成矿过程,为认识该类矿床铅锌成矿作用提供新地球化学依据。原位S同位素分析结果显示,乌斯河铅锌矿床硫化物的还原硫存在不同硫来源,成矿早阶段硫化物δ34S值较低,介于+1.3‰~+14.2‰之间,暗示可能有来自于赋矿地层圈闭古油气系统中的H2S;主成矿阶段硫化物相对富集重硫同位素,δ34S值在+11.0‰~+23.3‰之间,表明其为赋矿地层的蒸发岩的热化学还原作用的产物。此外,硫化物的LA-MC-ICPMS原位Pb同位素组成分析显示,该矿床成矿金属元素主要来源于变质基底地层,水岩反应可能使赋矿地层贡献少量的成矿物质。综合矿区地质特征和已有的地球化学研究成果,本文认为乌斯河铅锌矿床属于MVT铅锌矿床,富Pb、Zn等成矿元素的流体与富H2S的流体混合是该矿床金属硫化物沉淀的主要机制。  相似文献   
7.
An assessment of water quality measurements during a long‐lasting low water period in the Elbe River is presented. Weekly samples were taken from May to December 2003 at a sampling site in the middle part of the Elbe River. For multivariate data analysis, 34 parameters of 46 samplings were considered. As a result of this analysis, 78% of the variance of the data set is explained by five factors. They can be assigned to the following latent variables: season (37.5%) > tributaries (12.7%) > re‐suspension (10.4%) > discharge (9.4%) > complexation (8.5%). For the investigated sampling site, two key processes were identified as dominating factors on the water quality during low water conditions. First, seasonal phytoplankton development caused changes in redox conditions with consequences for re‐solution of pollutants from sediments. Second, tributaries have a higher impact on the main stream, due to changes in mixing processes. Therefore, in addition to flood investigations, monitoring strategies, and management plans should be developed in order to survey changes in water quality during low water conditions.  相似文献   
8.
Baker's yeast industry has significant effects on environment due to significant water consumption and high strength wastewater production. Effluents from baker's yeast industry are characterized by high concentrations of biological oxygen demand (BOD5), chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), total dissolved solids (TDS), sulfate, and dark brown color. The aim of this study is to provide a detailed quantitative and qualitative identification and characterization of the wastewater sources from different processes of a baker's yeast industry. It is identified that the most polluted wastewater components of the facility are coming from rotary drum filter and evaporation process. However, the highest pollution loads is identified as tank and equipment cleaning effluent due to very high flow rate from this source. The efforts should be on the way to minimize the water usage for the tank and equipment cleaning process, and to recycle less polluted waste streams back to the process.  相似文献   
9.
“井水不犯河水”水文地质学含义初步探讨   总被引:1,自引:0,他引:1  
利用水化学及同位素水文地质学的方法,对密云水库、潮白河及位于潮白河边的2个地下水分层专门监测井进行取样测试,并结合收集相关资料,从水位、水质及氚、氘、氧-18等同位素方面进行分析研究,对中国古语“井水不犯河水”的水文地质学方面的含义进行了一定的微观层次的分析探讨.得出研究点处潮白河水对50 m外的25 m深的浅井井水有...  相似文献   
10.
Carbon and nitrogen stable isotopes were used to investigate spatial variation in terrestrial particulate organic matter (POM) input to a coastal area off the Tagus river estuary. Isotopic variation in higher trophic level organisms was also examined, along the coast. This study was carried out in late summer, after a period of 3 months of low river flow. The overall aim was to determine if under such conditions the coastal area is enriched by the river plume and, particularly, if lower secondary productivity should be expected in some areas. Spatial variation was detected as a gradient of decreasing terrestrial input with increasing distance from the river. It was concluded that terrestrial carbon input was also incorporated into higher trophic levels and that organisms with lower mobility are more sensitive to the gradient in terrestrial input. Even in low flow conditions the whole fishing area remained under the influence of the river plume, which still accounted for 24% of the total POM 30 km from the river mouth. Additionally, δ15N values indicated pollution input from the river Tagus.  相似文献   
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