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北黄海沉积物中重金属分布及环境背景值 总被引：5，自引：0，他引：5
本文讨论了北黄海１１个柱状岩样的颗粒物（＜０．０６３ｍｍ）中重金属的分布，采用统计学方法对Ｃｕ，Ｐｂ，Ｚｎ和Ｃｄ进行态性检验，用柱样稳定段（拐点以下）作为背景段，获得重金属环境背景值。 相似文献
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渤海湾及其附近海域沉积物中Cu,Pb,Zn,Cd环境背景值的研究 总被引：10，自引：1，他引：10
根据渤海湾及其毗邻河口区10柱岩芯样细颗粒（＜0．063mm）（GF 1983－1985年采集）中重金属含量特点，结合^216Pb年代学编年资料，用未受人类影响沉积层中元素含量，藉统计学方法获得渤海湾岩芯样中Cu，Pb，Zn，Cd的分布类型，并根据各区重金属的含量水平，用t检验法获得了渤海湾Cu，Pb，Zn，Cd的环境背景值。 相似文献
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利用从珠江莲花山河段采集的淡水和大洋海水经过滤后，按不同盐度混合，模拟河口咸淡水交汇区重金属在水中各微粒级的分配特征。实验结果表明，在各种盐度条件下，Ｆｅ，Ａｌ，Ｃｕ，Ｐｂ，Ｚｎ和Ｃｄ主要以粒径＞１．０μｍ和＜０．２２μｍ的微粒存在于水中。在加入Ｆｅ（３＋），Ａｌ（３＋）模拟实验中，重金属绝大部分含量形成粒径＞１．０μｍ的微粒，其中Ｆｅ达９９％以上，Ｃｕ，Ｐｂ约９５％，Ａｌ约有７０％－９０％，Ｃｄ约４０％，其余部分主要以＜０．２２μｍ微粒存在。加入与未加入Ｆｅ（３＋），Ａｌ（３＋）的实验比较，Ｆｅ（３＋），Ａｌ（３＋）的加入对水中Ｃｕ，Ｐｂ，Ｚｎ和Ｃｄ含量向大微粒聚集有很大影响，使其聚集在粒径＞１．０μｍ微粒的量增加３０％－４０％。另外从实验结果和理论分析可知，水的盐度与重金属在位径＜１．０μｍ微粒中的含量分布无明显关系，但咸水中大量离子将对河水中胶体絮凝和微粒增长有重大影响。 相似文献
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海水分光反射率与叶绿素浓度的相关分析 总被引：1，自引：0，他引：1
通过对东京湾两年度不同季节海水分光反射率与叶绿素浓度进行统计分析，结果表明，叶素素浓度Ｃ与两谱段分光射率之比Ｒｗ（λｉ）／Ｒｗｗ（λ１）具有幂函数关系Ｃ＝Ａ［Ｒｗ（λｉ）／Ｒｗ（λｉ）／Ｒｗ（λｉ）］＾Ｂ．两者的对数显示出较好的线性关系，即ｌｏｇＣ＝ｌｏｇＡ＋Ｂｌｏｇ［Ｒｗ（λｉ）／Ｒｗ（λｉ）］。负相关系数达０．９９。相关方程之一为Ｃ＝３．３２９［Ｒｗ（５２０）／Ｒｗ（５５０）］＾－１．３８４（ 相似文献
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通过对东京湾两年度不同季节海水分光反射率与叶绿素浓度进行统计分析，结果表明，叶绿素浓度Ｃ与两谱段分光反射率之比Ｒｗ（λｊ）／Ｒｗ（λｊ）具有幂函关系Ｃ＝Ａ［Ｒｗ（λｊ）／Ｒｗ（λｊ）Ｂ。两者的对数显示出较好的线性关系，即ｌｏｇＣ＝ｌｏｇＡ＋Ｂｌｏｇ［Ｒｗ（λｊ）／Ｒｗ（λｊ）］。负相关系数达０．９９。相关方程之一为Ｃ＝３．３２９［Ｒｗ（５２０）／Ｒｗ（５５０）］－１．３８４（１９８７年６月初）．在梅雨季节之后，相关方程为Ｃ＝１２．６８［Ｒｗ（５２０）／Ｒｗ（５５０）］－２．０１０（１９８８年８月）。这表明了海湾或混浊的沿岸水质，在叶绿素浓度算法中，统计参数Ａ和Ｂ的确立，要基于不同季节不同水质的现场观测资料。 相似文献
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象山港重金属的环境化学特征 总被引：2，自引：0，他引：2
本文根据１９９０年６月和１１月对象山港海域进行的综合环境（水文、生物、化学）调查资料,分析了水体（包括溶解态、颗粒态）和沉积物的重金属（Ｃｕ、Ｐｂ、Ｚｎ、Ｃｄ、Ｃｒ）含量,运用元素的分布规律,探讨了该区的水动力因素、生物地球化学循环和沉积环境对重金属的影响,初步揭示了象山港重金属的环境化学特征。 相似文献
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本文研究了南海北部３１孔岩芯样的长链烯酮化合物的分布与微体古生物（钙质超微化石和浮游有孔虫）的关系。烯酮化合物主要来自定鞭金藻的赫胥黎艾氏石Ｅｍｉｌｉａｎｉｓａｈｕｘｌｅｙｉ，其中Ｃ３７∶２Ｍｅ含量在３１％～７０％。应用Ｃ３７的不饱和比值（Ｕ３７ｋ）计算了南海３１孔柱状样的海水古温度，波动幅度在２３．２～２８．３℃之间，平均为２５．３℃，低于该海域海水实测年平均温度（２８．１℃）。Ｕ３７ｋ值的变化与浮游有孔虫壳体的氧同位素值分期有着对应的关系，亦可相应分成５期。 相似文献
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广西北海潮间带沉积物中重金属的污染状况及其潜在生态危害 总被引：10，自引：0，他引：10
利用广西北海段潮间带表层沉积物样品的实验数据,对其沉积物中重金属（Hg,Cd,Pb,Zn,Cu,As）含量的空间分布特征进行了初步分析;并采用海洋沉积物重金属质量国家一类标准和Hakanson沉积物重金属潜在生态危害系数（Eir）与危害指数（RI）方法评价了该海域重金属污染程度和潜在生态危害。结果表明：北海段重金属的平均质量分数（mg/kg）为：Zn（69.81）〉Pb（16.58）〉Cu（12.76）〉As（9.08）〉Cd（0.22）〉Hg（0.07）;其中,廉州湾和英罗湾的重金属质量分数相对较高,而铁山湾和银滩段的相对较低。此外,绝大多数观测站点的沉积物尚保持清洁状态,且其潜在生态危害较轻,多属轻微生态危害。 相似文献
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不同海产动物和烟台海域不同海区的紫贻贝（Mytilus edulis）对重金属（Cr）富集的研究 总被引：1，自引：0，他引：1
产于烟台的５种海产经济动物对Ｃｒ的富集存在明显差异。底栖的滤食性贝类（紫贻贝Ｍ．ｅｄｕｌｉｓ、栉孔扇贝Ｃｈｌａｍｙｓｆａｒｒｅｒｉ、菲律宾蛤仔Ｒｕｄｉｔａｐｅｓｐｈｉｌｉｐｐｉｎｅｎｓｉｓ）的富集量远远超过自游泳的种类（中华马鲛Ｓｃｏｍｂｅｒｏｍｏｒｕｓｓｉｎｅｎｓｉｓ，长额七腕虾Ｈｅｐｔａｃａｒｐｕｓｐａｎｄａｌｏｉｄｅｓ）。紫贻贝为理想的海洋重金属Ｃｒ污染的指示动物．烟台海域各海区紫贻贝体内Ｃｒ含量最高，向边远海区逐渐降低。５种海产动物体内Ｃｒ的含量均在食品允许范围之内。 相似文献
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背景噪声的强弱是影响地震台站观测的一个重要因素。获取背景噪声的分布特征对评估海底地震仪记录数据质量及对数据的降噪处理均具有重要的指示意义。利用概率密度函数方法获取台站数据的功率谱密度的概率分布特征并与全球背景噪声高值模型和低值模型进行对比是研究台站周围环境背景噪声水平的有利手段。本研究基于南海大规模的被动源海底地震仪台阵长期观测实验的部分数据,利用概率密度函数方法研究了南海的背景噪声。首先,在全频段上对背景噪声进行了分析,并与其他台站做了对比,发现海洋的背景噪声在微震段和低频段大于高值模型且在全频带上远大于陆基台站的背景噪声,这表明海底地震仪数据质量并不高;其次,对观测过程中出现的地震事件以及其他典型信号的概率密度分布进行了归纳总结,发现远震事件、近震事件和数据丢失现象分别具有不同的优势频段和特征,这对后续滤波处理和质量检查具有重要指示意义;最后,研究了背景噪声的时间变化特征,发现台风是导致微震段时间变化的主要原因。 相似文献
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通过2008年和2009年布放在南海北部的声学多普勒流速剖面仪(ADCP)锚系潜标,本文观测到了三次由台风引起的近惯性振荡(NIO)事件,分别编号为2008a,2009a,2009b,并对其进行了比较研究.其中2008a在三次事件中强度最大,持续时间最长(15 d),而2009a和2009b仅分别持续了4 d和8 d.三次事件的垂直能量分布和位相传播有明显的区别.在频率偏移方面,2008a的峰值频率略低于局地科氏频率(红移),而2009a和2009b则体现出蓝移.不同的NIO事件的特征表现主要由台风扰动和背景流场环境共同决定,特别是背景流场通过平流和调制作用在其中起了重要的作用.本文的研究为不同背景流场中NIO的不同响应提供了观测的证据.通过分析数模提供的背景流场的涡度和有效科氏频率,2008a事件中较强的振幅和较长的持续时间是由于背景的剪切流场的波导效应造成,其改变了台风过后NIO的能量分布,将入射波能量集中于负涡度区域.而2009a和2009b事件中由于涡度不明显,因此没有类似效应. 相似文献
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Determination of carbon monoxide pollution of the atmosphere over Moscow with a spectroscopic method
E. V. Fokeeva E. I. Grechko A. V. Dzhola V. S. Rakitin 《Izvestiya Atmospheric and Oceanic Physics》2007,43(5):612-617
The results of measurements of the total content of carbon monoxide in an atmospheric column over Moscow and the Zvenigorod Scientific Station (ZSS) are given for the period 1993–2005. The simultaneous measurements of the regional background contents of carbon monoxide over a rural area (ZSS) and over Moscow made it possible to isolate an urban portion of the CO content. The total content of CO over the city varies significantly from day to day from values close to the background value to values that are 2.5–3 times greater than the background value. The number of days with such a CO content is 5% of the total number of measurement days. Such a CO content is most often observed during the cold seasons. During the warm seasons, in most of the cases, slight excesses of the CO background value are observed in the urban atmosphere. Variations in the CO content are determined mainly by wind-velocity variations and temperature inversions. In 2002, the high CO concentrations were due to forest and peatbog fires. On some days, over the ZSS, the concentrations of CO were high as never before. Over this period (12 years), the CO content in the surface air layer over the city did not increase. 相似文献
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Estimates of the characteristics of the horizontal turbulent exchange (coefficients of horizontal exchange, scales of deviations of the velocity of geostrophic currents from the background flows, and horizontal scales of perturbations) in the upper ocean layer were obtained on the basis of the data of expeditions held in 1978 and 1980 in the northwestern part of the Pacific Ocean. It is shown that the characteristics of the horizontal turbulent exchange strongly depend on the structure of the background flows, and one of the causes of their variability is related to tropical cyclones. A tendency to a decrease (to different degrees) of the turbulent coefficients in the wake of a tropical cyclone is noted. 相似文献
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Scleractinian corals create three-dimensional reefs that provide sheltered refuges, facilitate sediment accumulation, and enhance colonization of encrusting fauna. While heterogeneous coral habitats can harbor high levels of biodiversity, their effect on the community composition within nearby sediments remains unclear, particularly in the deep sea. Sediment macrofauna from deep-sea coral habitats (Lophelia pertusa) and non-coral, background sediments were examined at three sites in the northern Gulf of Mexico (VK826, VK906, MC751, 350–500 m depth) to determine whether macrofaunal abundance, diversity, and community composition near corals differed from background soft-sediments. Macrofaunal densities ranged from 26 to 125 individuals 32 cm−2 and were significantly greater near coral versus background sediments only at VK826. Of the 86 benthic invertebrate taxa identified, 16 were exclusive to near-coral habitats, while 14 were found only in background sediments. Diversity (Fisher’s α) and evenness were significantly higher within near-coral sediments only at MC751 while taxon richness was similar among all habitats. Community composition was significantly different both between near-coral and background sediments and among the three primary sites. Polychaetes numerically dominated all samples, accounting for up to 70% of the total individuals near coral, whereas peracarid crustaceans were proportionally more abundant in background sediments (18%) than in those near coral (10%). The reef effect differed among sites, with community patterns potentially influenced by the size of reef habitat. Taxon turnover occurred with distance from the reef, suggesting that reef extent may represent an important factor in structuring sediment communities near L. pertusa. Polychaete communities in both habitats differed from other Gulf of Mexico (GOM) soft sediments based on data from previous studies, and we hypothesize that local environmental conditions found near L. pertusa may influence the macrofaunal community structure beyond the edges of the reef. This study represents the first assessment of L. pertusa-associated sediment communities in the GOM and provides baseline data that can help define the role of transition zones, from deep reefs to soft sediments, in shaping macrofaunal community structure and maintaining biodiversity; this information can help guide future conservation and management activities. 相似文献
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F. V. Kashin V. N. Aref’ev N. I. Sizov R. M. Akimenko L. B. Upenek 《Izvestiya Atmospheric and Oceanic Physics》2016,52(3):247-252
Data on the volume concentration of carbon oxide (CO) in surface-air samples taken in European Russia, which were obtained using the Fourier transform spectroscopy method, are given. Over 16 years of measurements, this concentration decreased by 28%. These measured concentrations of CO are separated into its regional natural background and anthropogenic components. Seasonal variations in the concentration of CO are separated from its background concentration. Their extreme intra-annual values and mean amplitudes are determined. An empirical model of time variations in the concentration of CO is proposed. The atmospheric concentration of the CO anthropogenic component decreased by ~61 ppb over the measurement period. 相似文献
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The results of 2-year (2010–2012) measurements of the concentrations of organic carbon (OC) and elemental carbon (EC), which were taken at the Zotino Tall Tower Observatory (ZOTTO) Siberian background station (61° N, 89° E), are given. Despite the fact that this station is located far from populated areas and industrial zones, the concentrations of OC and EC in the atmosphere over boreal forests in central Siberia significantly exceed their background values. In winter and fall, high concentrations of atmospheric carbonaceous aerosol particles are caused by the long-range transport (~1000 km) of air masses that accumulate pollutants from large cities located in both southern and southwestern regions of Siberia. In spring and summer, the pollution level is also high due to regional forest fires and agricultural burning in the steppe zone of western Siberia in the Russian–Kazakh border region. Background concentrations of carbonaceous aerosol particles were observed within relatively short time intervals whose total duration was no more than 20% of the entire observation period. In summer, variations in the background concentrations of OC closely correlated with air temperature, which implies that the biogenic sources of organic-particle formation are dominating. 相似文献
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基于一套涡分辨模式数据,本文利用一种新的泛函工具—多尺度子空间变换—将孟加拉湾（BOB）海域的环流系统分解到背景流（>96 d）、中尺度（24～96 d）和高频尺度（<24 d）3个子空间,并用正则传输理论探讨了3个尺度子空间之间内在的非线性相互作用。结果表明,BOB西北部边界和斯里兰卡岛东部是BOB海域多尺度相互作用最显著的区域,中部则较弱。前两个区域的背景流大多正压、斜压不稳定,动能和有效位能正则传输主要表现为正向级串;后者则以逆尺度动能级串为主。具体来说,在BOB西北部与斯里兰卡东部,中尺度涡动能（EKE）主要来源于正压能量路径（即背景流动能向EKE传输）,其次来源于斜压能量路径（即背景流有效位能向中尺度有效位能传输,并进一步转换为EKE）。通过这两个能量路径得到的EKE向更高频的扰动传输能量,起到了耗散中尺度涡的作用。不同于此二者,BOB中部海域的EKE和高频尺度动能主要通过斜压路径获得,随后通过逆尺度级串将动能返还给背景流。苏门答腊岛的西北部也是中尺度和高频尺度扰动较强的海域,正压能量路径和斜压能量路径均是该海域扰动能的来源,但以斜压能量路径为主。 相似文献
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Michael F. Tlusty Anita Metzler Sara Huckabone Sutara Suanda Saskia Guerrier 《新西兰海洋与淡水研究杂志》2013,47(1):247-255
American lobster (Homarus americanus) have a thick calcified cuticle, and do not exhibit rapid colour changes characteristic of other crustaceans. Thus, the plasticity of their coloration has been largely overlooked. Colour in lobsters is determined by the amount, location, and form of the carotenoid pigment astaxanthin, and it is possible for lobsters to alter colour by changing one of these characteristics of astaxanthin deposition. Here, short‐term colour variation in American lobster in response to environmental cues (background colour and ultraviolet (UV) light) was investigated in a laboratory experiment. Lobsters were reared in conditions controlling background colour (white, black) and UV light (present, absent). Digital photographic analysis was used to determine how these conditions influenced the luminescence (light or dark) of lobster colour, as well as the ratio of red to blue hues. Of the environmental variables considered within this experiment, UV light was the predominant factor, and caused lobsters to become darker in colour. In the absence of UV light, lobsters matched background colour, and turned darker in response to the darker background. Environmental matching has practical implications both for wild lobsters as they settle to the benthic habitat, and for enhancement programmes, to grow lobsters that are best suited for local habitats. 相似文献