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1.
长江口海域表层沉积物重金属元素的潜在生态风险评价   总被引:10,自引:0,他引:10  
根据三峡水库一期蓄水3 a后(2006年)长江口海域表层沉积物样品中元素(Cd,Cr,Cu,Pb,Zn,Al,As,Ca和Sr等)质量比和黏土组分百分含量,采用Hakanson潜在生态风险指数法,分析了长江口海域表层沉积物中重金属元素(Cd,Cr,Cu,Pb,Zn和As)的污染程度,评价了长江口海域表层沉积物的环境质量现状,定量分析了长江口海域表层沉积物的潜在生态风险程度,并结合2003年的资料,讨论了三峡水库一期蓄水3 a后长江口海域的环境变化。结果表明,长江口海域表层沉积物环境质量状况良好,6种重金属元素的污染程度排序为:AsCrCdZnCuPb;表层沉积物的潜在生态风险程度为"轻度",6种重金属元素的潜在生态风险程度排序为:CdAsCuCrPbZn。从区域差异来看,杭州湾口外泥质区和长江口外东北偏北海域表层沉积物中重金属元素(As,Cr,Zn,Cu和Pb)的污染指数和潜在生态风险指数均出现相对高值。从元素差异来看,Cd的污染指数和潜在生态风险指数高值区的分布明显异于其他重金属元素,说明Cd存在与其他重金属元素不同的富集机制,很可能是因为Cd更易受悬浮体浓度、有机质含量以及水体盐度的影响。与2003年的资料相比,三峡水库一期蓄水3 a后(2006年)表层沉积物总体潜在生态风险程度和重金属元素(除Cd之外)潜在生态风险指数的高值区均未发生显著变化。  相似文献   

2.
莱州湾沉积物粒度与重金属分布特征   总被引:1,自引:0,他引:1  
作者依据2019年8月份莱州湾海洋沉积物调查资料,分析了该海域表层沉积物粒径组成、重金属时空分布特征并评价了其生态风险。结果显示,莱州湾沉积物分为砂质粉砂、粉砂、粉砂质砂和砂4种类型,以砂质粉砂为主,其次为粉砂与粉砂质砂,再次为砂,中值粒径平均58.956μm;表层沉积物中Cr、Zn、Pb、Cu、As、Cd、Hg和TOC平均含量分别为57.6、52.6、18.7、15.3、9.14、0.130、0.0234 mg/kg和0.222%;由于河流排海物质和莱州湾内潮流运动,导致Cu、Pb、Zn、As、Cr和Cd基本呈现中部海域含量较高,西部海域高于东部海域的特征,东南部海域Cd、Hg与矿产资源的开发相关;14.3%的站位综合潜在生态风险属于中生态风险,Cd对综合潜在生态风险指数的贡献率最高,为主要潜在生态风险因子;研究区域中重金属Cu、Zn含量的分布与沉积物粒径和有机碳的含量密切相关。  相似文献   

3.
基于2017年11月珠江口外陆架海域表层沉积物中Hg、As、Cu、Pb、Cd、Zn、Cr等7种重金属元素的调查结果,应用单因子标准指数和地累积指数法评价了研究海域表层沉积物环境质量,采用H?kanson潜在生态风险指数评价法定量评估沉积物中重金属的潜在生态风险,并利用Pearson相关性分析和主成分分析初步探究了研究海域沉积物中重金属的主要来源。结果表明:研究海域表层沉积物中7种重金属污染物含量均达到海洋沉积物质量一类标准,地累积指数显示研究海域表层沉积物环境整体处于清洁状态,部分站位中的As和Cd属轻度污染。总体来说,研究海域沉积物环境属于低潜在生态风险(综合潜在生态风险系数RI 150)。单项因子潜在生态风险由高到低为Cd Hg As Pb Cu Cr Zn,研究海域西部表层沉积物重金属Cd的潜在生态风险系数均值达到中等潜在生态风险水平。Cr、Cu和Zn元素具有相近来源,主要为工业产生的陆源污染物; Pb、As和Cd元素来源相似,来源于陆源工业和农业污染经大气沉降及海上交通污染;而Hg与其他重金属元素无明显相关。  相似文献   

4.
对2009年春、秋两季辽东湾西部海域共25个采样站位4种重金属含量的分布特征进行了研究,并利用潜在生态风险指数法和地质累积指数法对其污染状况进行了评价.结果表明:该海域表层沉积物中Cu、Pb、Zn和Cd平均含量范围分别为8.0~32.1、4.3~56.9、20.0~102.6、0.12~0.34 mg/kg;Cu、Pb、Zn和Cd含量平均值均高于渤海重金属背景值.在该海域表层沉积物重金属单元素平均含量的潜在生态风险指数中,Cd的风险等级已经达到"中等",Cu、Pb和Zn的潜在生态风险等级"较低";各重金属元素综合潜在生态风险等级属于"中等",近岸及河口等海域的生态风险等级相对较高.重金属地质累积指数评价结果显示,Cu和Zn属于0级污染,Pb和Cd属于"轻度"污染.因此,作者建议应控制该海域近岸养殖区密度和减少养殖污染.表层沉积物中重金属和TOC含量相关性分析表明:该海域表层沉积物中重金属Cu、Pb和Zn具有一定的同源性,TOC含量对重金属分布具有一定的影响.  相似文献   

5.
根据日照近海13个站位表层沉积物粒度和重金属含量测试结果,分析了研究区表层沉积物粒度和重金属含量分布特征,采用地累积指数法和潜在生态风险指数法评估了研究区重金属污染状况和潜在生态风险,探讨了重金属的来源和控制因素。结果表明,研究区表层沉积物可分为粉砂、粉砂质砂、砂质粉砂等3种类型,沉积物类型主要呈大致平行岸线的条带状分布,由岸向海依次为粉砂 砂质粉砂 粉砂质砂。研究区表层沉积物中Cr、Zn、Pb、As、Cu、Cd、Hg等重金属的平均含量由高到低依次为45.5、21.8、16.4、8.5、4.8、0.113、0.11 μg/g。从空间分布特征来看,Cr、Cu、Zn和Pb高值区主要出现在付疃河口近岸和研究区中西部海域,Cd和As高值区位于研究区中东部海域。污染状况评估显示,Cr、Cu、Zn、As未出现污染;Cd轻度污染,个别站位达到中度污染,Hg、Pb部分站位呈轻度污染。潜在生态风险等级依次为:Cd>Hg>Cu>As>Pb>Cr>Zn,其中Cd和Hg表现为中生态风险,个别站位Cd为高风险危害。表层沉积物中Cu、Cr、Zn、Hg和Pb元素主要来源于陆源细粒物质的输入,Cd和As元素可能来源于钢铁冶炼、煤炭燃烧、农药、化肥以及海水养殖等。研究区表层沉积物中重金属空间分布主要受物源控制。  相似文献   

6.
辽东湾表层沉积物的重金属污染特征与质量评价   总被引:1,自引:1,他引:0  
本文研究了辽东湾表层沉积物中重金属的分布及污染特征,评价其生态风险及环境质量。对辽东湾表层沉积物8种重金属(As、Cu、Cd、Cr、Hg、Ni、Pb、Zn)的空间分布进行了研究,采用Hankanson法和Igeo(地累积指数)分析了该海域重金属潜在生态风险,并评价了该海域的环境质量。在辽东湾葫芦岛附近海域、西南部六股河口东南部海域以及西部近岸海域表层沉积物中As、Cu、Cd、Cr、Hg、Ni、Pb和Zn含量偏高。地累积指数法及生态风险指数法对重金属污染程度评价结果一致,辽东湾生态环境具有潜在危害的重金属主要是Cd、Hg和As,8种重金属潜在生态风险系数由高到低依次为Cd、Hg、Cu、Pb、As、Zn、Ni和Cr,各站位重金属综合潜在生态风险指数均大于150,生态风险总体上处于中等生态风险等级。Cd和Hg是该海域沉积物重金属中主要污染物,局部区域达到中、中-强污染程度。环境质量评价表明,辽东湾表层沉积物重金属引发有害生物效应的可能性不大,但Cd和Hg显著富集,应予以重视。  相似文献   

7.
根据2008—2015年3个航次对曹妃甸附近海域共51个采样站位的表层沉积物调查资料,分析了表层沉积物中Hg,Cu,Pb,Cd,Cr,Zn和As七种重金属的质量分数和年际变化特征,采用超标率统计法、地累积指数法和潜在生态风险指数法对其重金属含量进行了评价。结果表明,研究海域表层沉积物中重金属含量总体处于较低水平,3个航次中仅有1个站位的Cu超标,其他调查站位的重金属含量均符合第一类标准。研究海域表层沉积物中各重金属的年际变化略有差异,Cu,Pb和Zn的含量相对比较稳定;Cr的含量表现为逐年降低的趋势;Cd和As的含量表现为先降低后增大的趋势;而Hg的含量表现为先增大后略降低的趋势。近8a来总体上曹妃甸附近海域表层沉积物中重金属含量的年际变化不显著。采用地累积指数法评价显示,7种重金属元素的Igeo多年平均大小排序为CdPbHgCuCrZnAs,除个别站位Cd受到轻度污染外,其他6种重金属污染程度均为清洁。采用潜在生态风险评价显示,研究海域7种重金属的Eir多年平均大小排序为CdHgAsPbCuCrZn,综合潜在风险指数等级为低生态风险水平。结合地累积指数法和潜在生态风险指数法两种评价方法得出的评价结果一致,结果表明Cd是曹妃甸附近海域表层沉积物中主要潜在生态风险因子。  相似文献   

8.
为了解惠州近岸海域沉积物重金属的污染特征,于2016-08采集表层沉积物12个,分析了沉积物中Cu,Zn,Pb,Cd,Cr,Hg,As的含量,采用地积累指数法(Igeo)和潜在生态风险指数法(Eir)进行重金属污染现状和生态风险评价。结果表明:参照国家《海洋沉积物质量》标准(GB 18668—2002),惠州近岸海域沉积物质量整体良好,沉积物中7种重金属元素含量符合第一、二类标准。地积累指数法和潜在生态风险指数法评价结果显示,惠州近岸海域沉积物7种重金属元素的污染程度为CdZnAsCuPbHgCr,Cd在所有样点都是偏中度污染及以上,Pb,Cr,Hg三种元素皆为无污染;沉积物中7种重金属元素的潜在生态风险系数(E_r~i)由高到低依次为CdHgAsCuPbZnCr,Cd具有极强生态风险,沉积物重金属处于强生态风险状态(RI平均值为370.22),Cd是主要的生态风险贡献因子。沉积物中Cu,Zn,Pb,Cr四种元素显著相关,具有同源性;有机碳显著作用于沉积物重金属含量和分布。  相似文献   

9.
为了解辽东湾西北部海域沉积物重金属的分布特征及污染程度,文章基于2017年3月辽东湾西北部12个采样站位表层沉积物7种重金属含量(Hg、Cu、Pb、Cd、Zn、Cr、As)的测定,对辽东湾西北部海洋沉积物中的重金属进行了研究。SPSS用于沉积物中重金属含量统计分析并通过地累积指数和潜在生态风险指数的方法评估重金属污染和生态危害的程度。结果显示:(1)辽东湾西北部沉积物重金属含量平均值只有Cd符合海洋沉积物一类标准,变异程度由高到低依次为Hg、Cd、As、Zn、Pb、Cu,汞和镉受人为来源控制最高;(2)地累积指数法评价结果表明重金属元素污染程度由大到小依次为Hg、Cd、Zn、As、Cu、Pb;(3)潜在生态风险指数法评价结果表明,单因子潜在生态风险系数由高到低依次为Hg、Cd、As、Cu、Pb、Zn、Cr,Hg具有很强的生态风险,综合生态风险指数在233.77~4785.15,平均1224.12,处于很强的生态风险水平。文章揭示了辽东湾西北部海域沉积物重金属的分布特征,为该海域的生态环境建设提供依据。  相似文献   

10.
基于2014年4月庙岛群岛南部海域的调查资料,综合运用单因子指数法、地质累积指数法和潜在生态风险指数法3种方法,研究了海水和表层沉积物重金属元素的含量分布特征,并对重金属元素进行了污染评价和生态风险分析。结果表明:调查海域海水中Zn、Hg、Cu和Cd均符合第一类或第二类海水水质标准,15%站位的Pb超第二类海水水质标准;表层沉积物中7种重金属均符合第一类沉积物质量标准,沉积物质量良好;地质累积指数评价结果表明沉积物中重金属污染程度由高到低为ZnAsPbCrCuCdHg,Hg均处于清洁状态,As、Pb、Cr、Cu、Cd均有部分站位呈轻度污染状态;潜在生态风险指数表明沉积物中重金属综合潜在生态风险程度为中,7种重金属潜在生态风险由高到低为CdHgAsPbCuZnCr,Cd和Hg为调查海域沉积物重金属主要潜在生态风险因子;Pearson相关分析结果表明Zn、Cr、Hg、Cu、Pb、As之间呈显著相关(P0.01),具有相似的来源特征。庙岛群岛南部海域重金属的来源主要包括黄河入海泥沙悬浮物输送、周边沿岸入海径流输入、港口码头船舶引入和大气沉降输入等。应加强对庙岛群岛南部海域海水中Pb及表层沉积物中Cd和Hg的监测,重点关注沉积物中Cd和Hg相对高值区的潜在生态风险。  相似文献   

11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

13.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

14.
双壳贝类血淋巴中儿茶酚胺的检测方法初步研究   总被引:1,自引:0,他引:1  
研究的目的是探索一种检测双壳贝类血淋巴中儿茶酚胺含量的方法。以栉孔扇贝(Chlamysfarreri)和长牡蛎(Crassostreagigas)为实验对象,研究了取样、抗氧化剂、氧化铝用量以及Tris缓冲液用量等对实验结果的影响。结果表明,高效液相色谱电化学检测器法(HPLC-ECD)可以灵敏高效地对双壳贝类血淋巴中儿茶酚胺进行定性、定量检测。实验表明,取样时间最长不超过1.5min;还原性谷胱甘肽作抗氧化剂效果较好;前处理各试剂与血样量的最适配比为血样量1.5mL,Tris缓冲液(1.5mol/L,pH8.6)1mL和氧化铝25mg;水洗后离心并尽可能吸干氧化铝中的水分。去甲肾上腺素、肾上腺素和多巴胺的回收率分别为53%~69%、47%~73%和48%~56%。  相似文献   

15.
为研究黄河入海径流变化条件下河口附近海域盐度扩散特征,以更好地保护河口海域生物资源多样性,本文以黄河下游利津水文站的长序列实测径流数据资料为基础,利用近海水动力模型FVCOM,分析径流变化对黄河口海域盐度的影响规律。结果表明:黄河口与莱州湾之间存在顺时针的环流系统,在余流作用以及涨落潮方向的影响下,黄河冲淡水长期向莱州湾扩散;丰水期黄河冲淡水几乎影响了整个莱州湾,27盐度锋可以到达莱州湾中部,27等盐线的表层包络面积为2 665.61 km2,占莱州湾的1/4左右,枯水期低盐度水只有向南扩散的趋势,27以下的低盐度水集中分布在黄河口门附近,27等盐线的表层包络面积只有199.65 km2;5月份,随着入海径流量增加,27等盐线扩散的范围、距离、方向都会发生明显变化。在对近海生物资源有迫切保护需求的情景下,适当减少其他用水户供水量以增加入海生态径流量,可以有效改善黄河口海域附近的盐度情况,为生物资源的生长繁殖创造良好条件。  相似文献   

16.
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

17.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

18.
The authors have previously determined that the effectiveness and failure pattern of the ice cover caused by flexural-gravity waves generated by a submerged body motion near the bottom ice can greatly depend on the depth of the water area. In its turn, the presence of a ledge on the ice surface may affect a wave propagation pattern. This paper presents an experimental study of the bottom contour influence on the deflection and length of flexural-gravity waves. The authors describe a numerical model for the analysis of the deformed state of ice caused by hydrodynamic loads due to a submarine motion, taking into account the bottom contour. The experiments are carried out in the ice tank. The results of calculations and experiments are compared.  相似文献   

19.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

20.
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption (fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem, which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge, water exchange with the Black Sea, etc.). Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

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