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1.
Towards continuous long-term measurements of suspended particulate matter (SPM) in turbid coastal waters 总被引：1，自引：1，他引：0
Thomas H. Badewien Elke Zimmer Alexander Bartholomä Rainer Reuter 《Ocean Dynamics》2009,59(2):227-238
The dynamics of sediment transport in the East Frisian Wadden Sea are important for the coastal zone and for ecosystem functioning.
The tidal inlets between the East Frisian islands connect the back-barrier intertidal flats to the North Sea. Here, concentrations
of suspended particulate matter (SPM) in the water column are highly variable, depending on weather conditions and tides.
In order to estimate the nature and quantity of sediment transport, in situ measurements were carried out at a Time Series
Station in the tidal inlet between the islands of Spiekeroog and Langeoog. This study shows the suitability of multispectral
transmissometry (MST) for obtaining long-term SPM measurements with high resolution. The comparability of this technique to
the standard filter method and the laser diffraction method [laser in situ scattering and transmissometry (LISST)] is demonstrated.
In addition, the Junge coefficients derived from both MST and LISST measurements are compared. A time series of SPM data covering
nearly 4 months is presented. As a major result, the data reveal that a single storm surge can have less impact on SPM dynamics
than longer-lasting gales. This high-resolution long-term data set is very valuable for modelling suspended matter flux. It
also provides background information for studying the influence of SPM dynamics on coastal sediments. 相似文献
2.
矿物及材料表面的SPM微形貌研究 总被引：2，自引：0，他引：2
廖立兵 《矿物岩石地球化学通报》1999,(2)
矿物及材料表面形貌研究手段经历了从肉眼和手指到触针技术、光学技术及扫描电镜,最后到扫描探针技术（ｓｃａｎｎｉｎｇｐｒｏｂｅｍｉｃｒｏｓｃｏｐｙ,简称ＳＰＭ）的发展阶段,使可获取的表面形貌信息量不断丰富,分辨率不断提高,研究从宏观进入微观,从定性进入了... 相似文献
3.
在2007年底至2008年初的枯水期间,系统采集了中国东部流域面积和径流量较大的33条河流沉积物、悬浮颗粒物和水样,采用等离子质谱法、X荧光光谱法等方法测定了14种稀土元素含量以及常量组分和水体pH值等理化指标。研究发现中国河流稀土元素浓度总体高于世界均值,且南方河流沉积物、悬浮物稀土元素含量高于北方河流,南方河流悬浮物态中稀土、重稀土呈现一定程度的相对富集,与我国上地壳稀土丰度和稀土矿产种类的南北分异相吻合。展示了以中国东部泥质岩稀土元素丰度标准化后的稀土配分模式及Ce、Eu异常特征,发现河流沉积物的中、重稀土元素相对富集,悬浮物轻稀土相对富集,溶解相重稀土富集的特征;北方河流溶解相稀土元素浓度明显大于南方河流,且除小清河外,溶解相Eu不同于沉积物与悬浮物而呈强烈的正异常,主要与河水理化性质影响下的稀土分异有关。研究发现小清河等少数河流沉积物中稀土元素为异常高值,经Al标准化处理、计算拟合剩余值后,认为小清河等河流稀土元素已受人为污染的影响。 相似文献
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5.
When using Transient Geo-Electromagnetics (TEM) unusually slow decaying transients are sometimes observed in the absence of well-conductive objects. Many researchers explain this phenomenon by presence of material with magneto-viscous or superparamagnetic (SPM) properties. The analysis of electromagnetic (EM) field equations in conductive SPM medium is suggested in the present paper. It is shown that in a simplest case of small size single-domain magnetic particles with relative higher potential barrier energy, the SPM-medium is characterized by a very slow decaying exponential transient magnetic field, the level of which is much more as compared to that of due to non-magnetic medium of the same conductivity. This situation is traced up to the late transient time like 0.1 s and more. SPM and Induction fields are in the near zone additive. They depend in a different way on the superparamagnetic and electric properties of the SPM-medium. They also depend in different ways on the transient time and on the size of the transmitter–receiver configuration. These characteristics make it possible to recognize the presence of SPM-effect and to separate these fields. 相似文献
6.
桑沟湾夏、秋季悬浮颗粒物的沉降通量及再悬浮的影响 总被引：1，自引：0，他引：1
应用锚式悬挂沉积物捕捉器法,研究了我国北方重要海水养殖区域桑沟湾悬浮颗粒物沉降通量的分布特征,并通过金属Al标记法,同步测定了沉降颗粒物再悬浮比率。结果表明,桑沟湾的底层悬浮颗粒物(SPM)、颗粒有机碳(POC)、颗粒态总氮(PTN)和颗粒态总磷(PTP)平均表观沉降通量分别为1 511.4g/(m2·d)、20.01g/(m2·d)、1.497g/(m2·d)和0.474g/(m2·d),显著高于我国其他近岸海域,但底层沉降颗粒物再悬浮比率平均值高达92.8%,认为在养殖内湾,受再悬浮程度的影响,测得的底层表观沉降通量是中层的2.7倍,秋季明显大于夏季,海带和扇贝养殖区大于牡蛎养殖区。经再悬浮比率校正后的净沉降通量,仍存在着显著的空间和季节变化,但受控因素发生了根本转变;这主要表现为净沉降颗粒物质主要源于生物代谢活动强烈中上层水体,贝类的排泄作用使牡蛎和扇贝养殖区的净沉降通量显著大于海带养殖区,养殖贝类个体增大、排泄量增加使秋季净沉降通量高于夏季。在我国近岸海域,再悬浮作用的影响,会对该区域悬浮颗粒物沉降通量的估算带来巨大误差,因此该作用不容忽视。 相似文献
7.
厦门湾水体中铀、钍同位素及悬浮颗粒物的粒径谱--颗粒物采集方法的影响 总被引：2，自引：0，他引：2
运用增强型混合纤雏素(CN-CA)膜、聚碳酸酯膜和聚丙烯滤芯过滤3种不同的方法采集、研究厦门湾水体中悬浮颗粒物(SPM)及其U、Th同位素的粒径谱．发现3种方法所得SPM总浓度和U、Th各同位素的总比活度具有很好的一致性,但粒级分布存在差异．SPM的浓度随粒径的增大而增加,并且SPM的粒径谱控制着颗粒活性很强的4种钍同位素的拉径谱．对于所研究的3种方法,采用聚碳酸脂膜过滤是研究沿岸海域SPM及颗粒活性核素粒级分布比较理想的方法。 相似文献
8.
J. Deloffre R. Lafite P. Lesueur S. Lesourd R. Verney L. Guzennec 《Estuarine, Coastal and Shelf Science》2005,64(4):1073
In order to understand the hydrodynamic parameters that control the fluvial sediment dynamics on an intertidal mudflat located in a sheltered zone in the upper part (fluvial part) of the macrotidal Seine estuary (France), a two-year field study of high-frequency field measurements was carried out. The bed-level evolution of the mudflat surface was measured from the semi-diurnal period to annual time scales using a high-resolution altimeter. The data showed that the sedimentary patterns on the mudflat were mainly controlled by river flows and tides. During high river flows in winter, sedimentation dominated; suspended particulate matter concentrations were higher, submersion was constant and at semi-diurnal scale, sedimentation duration was more important than erosion due to an asymmetrical tide. By contrast during low river flows in summer, erosion dominated mainly as a result of immersion/emersion of tidal flats during semi-diurnal cycle. From this annual sedimentation–erosion cycle we identify a temporary storage of 10–30% of the fine-grained (<63 μm) river-borne particles on mudflats in the upper section of the fluvial Seine estuary during high river flows.River-related sediment fluxes were estimated from the measurement of fine-grained sedimentation zones in the fluvial part of the estuary. The erosion/sedimentation processes were perennial, and the amounts of contributing sediments were directly related to the solid river load. Our results indicate that mudflats in the fluvial part of the Seine estuary play an important role in the downstream transfer of fine-grained suspended particulate matter (SPM) towards the turbidity maximum and the Rouen docks particularly during low river flows, when roughly 30–50% of the SPM originates from the eroded intertidal flats. 相似文献
9.
贵阳市红枫湖水体悬浮物中重金属污染及潜在生态风险评价 总被引：7，自引：1，他引：6
研究了红枫湖水体中悬浮物重金属（Zn、Cu、Cr、Pb和Cd）的季节性和空间性污染特征,采用Hakanson潜在生态危害指数法评价了水体悬浮物中重金属的潜在生态危害。结果表明,重金属随着季节和空间变化都较大;产生潜在生态危害的重金属主要是Cd和Pb,分别达强度生态危害水平和中度生态危害水平,Cu、Zn和Cr显示轻度危害水平;潜在生态危害综合指数RI=226．09,说明重金属污染已达到中度生态危害。红枫湖悬浮物重金属潜在生态危害指数的季节性变化顺序为二月〉六月〉四月〉十二月〉十月〉八月,空间变化顺序为化肥厂河〉麦包河〉猫跳河〉桃化源河〉后六河〉羊昌河〉北湖〉麻线河〉南湖。 相似文献
10.
Anja Stojanovic Daniel Kogelnig Dieter Mader Rudolf Krachler 《Chemie der Erde / Geochemistry》2009,69(3):223-234
General geochemical parameters of water, superficial sediments, and suspended particulate matter (SPM) were determined from small shallow saline lakes (soda ponds) as well as from lake Neusiedlersee in eastern Austria. Additionally, instrumental neutron activation analysis (INAA) was used to determine the distribution of major, rare earth and other trace elements in superficial sediments and SPM. Chemical results show remarkable differences in salinity and ionic strength between the investigated ponds. Anthropogenic effects, such as drawdown of ground water level and a loss of lake water due to drainage, are clearly reflected in obtained chemical and geological data. Due to a strong dependence of the complexation and scavenging behavior of the rare earth elements (REE) on ionic strength, a significant difference between REE concentrations in soda ponds with different anthropogenic impact was found. The content and composition of authigenic evaporitic minerals in superficial sediments and SPM clearly differ with a fluctuating water level and salt concentration. Furthermore, we determined the distribution of major and trace elements in superficial sediments of a nearby fluvial system. Our results show a clear correlation between REE superficial sediment concentrations in anthropogenically degraded soda ponds and fluvial system. Therefore, we assume that REE concentrations of sediments and SPM are suitable for the study of geochemical changes of inland saline lakes due to anthropogenic impacts on water balance. 相似文献