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1.
Chemical water quality determinants and river water fluorescence were determined on the River Tyne, northeast England. Statistically significant relationships between nitrate (r = 0.87), phosphate (r = 0.80), ammonia (r = 0.70), biochemical oxygen demand (BOD) (r = 0.85) and dissolved oxygen (r = -0.65) and tryptophan-like fluorescence intensity were observed. The strongest correlations are between tryptophan-like intensity and nitrate and phosphate, which in the Tyne catchment derive predominantly from point and diffuse source sewage inputs. The correlation between BOD and the tryptophan-like fluorescence intensity suggests that this fluorescence centre is related to the bioavailable or fluorescence intensity and ammonia concentration and dissolved oxygen. The weaker correlation with ammonia is due to good ammonia treatment within the wastewater treatment plants within the catchment, and that with dissolved oxygen due to the natural aeration of the river such that this is not a good indicator of water quality. Mean annual tryptophan-like fluorescence intensity, measured by both bench and portable spectrometers, agrees well with the General Water Quality Assessment as determined by the England and Wales environmental regulators, the Environment Agency.  相似文献   

2.
In order to characterize the pollution discharged into the Moselle River and some of its tributaries, spectroscopic techniques, namely UV-vis spectroscopy and synchronous fluorescence spectroscopy, have been combined. UV-visible spectra were analysed using the maximum of the second derivative at 225 nm (related to nitrates), the SUVA254 and E2/E3 indices (related to the nature of organic matter). Synchronous fluorescence spectra (delta lambda = 50 nm) presented different shapes depending upon the type of pollution. The pollution results from anthropogenic activities: untreated domestic sewage due to misconnections in a periurban river, effluent from urban WWTPS, agricultural runoff (nitrates) in several streams, discharge from a paper mill (humic-like substances due to wood processing) and from steel mills (PAHs).  相似文献   

3.
紫色土丘陵区典型生态-水文单元径流与氮磷输移特征   总被引:1,自引:0,他引:1  
通过对紫色土丘陵区典型农业-集镇-林地复合型小流域3次降雨-径流全过程的连续监测,测定径流过程中泥沙含量和不同形态氮磷浓度,以期认识典型农村生态-水文单元降雨径流过程中氮磷迁移规律。结果表明:降雨-径流过程中悬浮泥沙的流失主要集中在径流前期,其峰值出现在雨强最大时;集镇径流污染的影响主要表现在径流前期,是径流前期铵态氮偏高的主因;降雨-径流过程中,颗粒态氮与可溶态氮比(PN/DN)、颗粒态磷与可溶态磷比(PP/DP)的峰值均出现在雨强较大时:其中PN/DN多小于1,而PP/DP范围为1.1~30.2,说明氮素流失主要通过可溶态的方式,而磷的迁移以颗粒态磷为主。因此在紫色丘陵区建议利用湿地植物与沉砂池等综合措施控制土壤侵蚀和非点源污染以保护当地生态环境安全。  相似文献   

4.
The fluorescence excitation-emission matrices (FEEM) of domestic waste water, treated effluent of a waste water treatment plant and receiving river water were analyzed to select wavelengths for the monitoring of organic contents as COD. Excitation/emission wavelengths of 220/350 nm and 270/350 nm for protein-like fluorescence and 240/450 nm and 340/450 nm for humic-like fluorescence were suggested as fluorescence peak emitting wavelength pairs, respectively. Without any pre-treatment, the protein-like fluorescence peaks showed better correlation between COD values and fluorescence intensities than the humic-like fluorescence peaks. No enhanced correlation was observed by removing the suspended solids from the samples using filtration. However, statistical multiple regression methods, using the fluorescence intensities from each peak and the light scattering intensity at 633 nm as variables, resulted in an enhanced correlation, with r2 > 0.9 for the measured and predicted COD values.  相似文献   

5.
A coliforms monitoring system in treated effluent of a wastewater treatment plant has been developed. In order to achieve rapid monitoring within 1 hour, an enzymatic fluorescence method without a culturing process was introduced to this system. It converts the increase rate of fluorescence intensity as enzymatic activity into the number of coliforms instead of converting fluorescence intensity itself. A flow injection analysis is used in this system for automatic measurement. Moreover, it is equipped with the pre-filtering unit to remove the interfering substances in the suspended solids causing deterioration in measurement precision. The good relationship (correlation coefficient of 0.90) between the obtained values using this system and the analysed values using the conventional direct counting method was observed in a test at an existing wastewater treatment plant.  相似文献   

6.
沉积物中砷、汞测定新方法的实验条件分析与研究   总被引:1,自引:0,他引:1       下载免费PDF全文
本文对微波消解沉积物样品中砷、汞的条件进行了优化实验,并对海河流域漳卫南运河沿岸的25个沉积物样品进行了测定,结果令人满意。本次实验条件的优化为下一阶段的全国沉积物污染情况调查奠定了基础。在优化的实验条件下,采用原子荧光光谱测定砷和汞的检出限分别为0 01μg L和0 001μg L,线性范围分别为0~100μg L和0~50μg L,两元素的回收率在90%~104%之间,相对标准偏差分别为2 88%和5 71%。  相似文献   

7.
为探讨重金属离子Cd~(2+)对铜绿微囊藻的毒性效应,通过室内实验,研究了铜绿微囊藻在不同Cd~(2+)浓度胁迫下的生理生化变化。结果表明:1 Cd~(2+)对铜绿微囊藻具有明显的毒害作用,Cd~(2+)对铜绿微囊藻的24hEC_(50)、48h-EC_(50)、72h-EC_(50)、96h-EC_(50)分别为0.978,0.863,0.646,0.302 mg/L,随着作用时间的延长,EC_(50)显著降低(P0.05);2在Cd~(2+)胁迫下,铜绿微囊藻的光合生理特性受到不同程度的影响,叶绿素荧光特性Fv/Fm、Y[Ⅱ]、ETR、q P变化趋势基本一致,且与叶绿素a都表现出剂量-效应关系;3 Cd~(2+)诱导藻细胞产生氧化应激反映,其中丙二醛(MDA)和超氧化物歧化酶(SOD)活性均显著升高(P0.05),且随暴露时间延长,氧化应激强度增大。综上,重金属离子Cd~(2+)能够抑制铜绿微囊藻的生长,阻碍其光合作用,同时造成氧化应激效应。  相似文献   

8.
The goal of the study was to compare the modes of management of seasonal floods for different dams and to constrain their impact on the relationship between climate variables and streamflow downstream from the dams. At the Rawdon dam, downstream from which the Ouareau River is characterized by a natural‐type regulated flow regime, a ‘type A’ flood management mode prevails, in which the same rainfall and/or snowmelt events account for seasonal floods both in the unregulated (natural) stretch of river upstream from the dam and in the river downstream from the dam. As a result, seasonal floods in the natural setting and downstream from the dam are nearly synchronous. In contrast, downstream from the Matawin dam (Matawin River), which produces an inversion‐type regulated flow regime, the prevalent flood management modes are of types B and D, whereby seasonal floods observed upstream and downstream from the dam are not caused by the same rainfall and/or snowmelt events and, as a result, are not synchronous. This difference in seasonal flood management modes affects the interannual variability of the magnitude of seasonal daily maximum flows related to the seasonal floods. Thus, the interannual variability of these flows downstream from the Matawin dam differs significantly from that of flows upstream. No correlation is observed between climate variables and streamflow downstream from the Matawin dam. This absence of correlation disappears gradually at the annual scale, at which streamflow is correlated with rainfall, as is observed upstream from the dam. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

9.
Four 10-m sediment cores from the Cedarburg Bog, Wisconsin, were collected for paleomagnetic measurement and carbon-14 dating. The paleomagnetic records for these cores are self consistent, with the intensity record affording the best correlation. These results are compared with sediment cores from Lake Michigan. The two sets of cores are unmistakably correlatable on the basis of intensity. The inclination correlation also shows common long and short wavelength features.On the basis of this correlation, we date certain member boundaries of the Lake Michigan Formation as follows: Waukegan–Lake Forest, 5,500 years B.P.; Lake Forest–Winnetka, 7,800 years B.P.; and Winnetka–Sheboygan, 9,700 years B.P.  相似文献   

10.
Research on the effects of chemical pollution in the environment that is related to urban wastewaters?? discharge and reuse until recently was focused almost exclusively on conventional pollutants. During the last several years though there has been a growing level of concern related to the hypothesis that various chemicals may exhibit endocrine disrupting effects. In addition, thousands of tons of pharmacologically active substances are used annually ending up in the wastewaters. In many countries facing prolonged droughts and implementing wastewater reuse schemes for irrigation and groundwater discharge, the existence of xenobiotic compounds in the tertiary treated wastewaters constitutes a new concern. This study describes the application of a recently developed multi-residue method for the determination of 29 multi-class pharmaceuticals using off line solid phase extraction followed by liquid chromatography?Ctriple quadrupole mass spectrometry (LC?CMS?CMS). The method was applied for the analysis of pharmaceutical residues at three sewage treatment plants in Cyprus serving major coastal Mediterranean cities. The presence of 19 pharmaceuticals was confirmed. For some of the compounds high concentrations were obtained for the final effluents (e.g. ofloxacin: 4.82 ??g/L, diclofenac: 5.51 ??g/L, carbamazepine: 27.27 ??g/L, metoprolol: 9.59 ??g/L). Concerning the elimination potential, what was derived from the study is that the biological treatment step contributes the most to the removal of the compounds while sand filtration and chlorination steps reduce slightly the residual concentrations.  相似文献   

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