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51.
海河干流、大沽排污河沉积物中有机氯农药的残留状况 总被引:7,自引:0,他引:7
调查了海河干流和大沽排污河沉积物中持久性有机氯杀虫剂(OCPs)的残留状况.在所选取的16个断面沉积物样品中均有大量HCHs、DDTs检出,表明海河和大沽排污河的DDT和HCH污染相当严重.海河沉积物中HCHs和DDTs总质量浓度分别为3.30~75.96、1.57~221.57 ng/g.大沽排污河沉积物中HCHs和DDTs的残留量分别为2.30~124.61、11.28~237.30ng/g.与国内外部分河流表层沉积物中HCHs、DDTs的含量相比,海河和大沽排污河沉积物中有机氯农药含量较高.最后根据两条河流沉积物中的OCPs的残留量,分析了其可能的污染源. 相似文献
52.
Occurrences of pharmaceutical and personal care products as micropollutants in rivers from Romania 总被引:15,自引:0,他引:15
Moldovan Z 《Chemosphere》2006,64(11):1808-1817
The occurrence of pharmaceutical and personal care products (PPCPs) was investigated in the Somes River. The aim of this study was to obtain a first overview about the contamination of Somes River (Transylvania) with PPCPs. The samples were preconcentrated by Solid Phase Extraction (SPE) procedures and analysed by GC/MS. A number of 15 compounds including pharmaceutics, metabolites, intermediates and musk fragrances were detected in concentration ranging from 30 ng/l to 10 μg/l. The detected pharmaceuticals are included in following therapeutic groups: analgesics, antiepileptics, psychiatric, stimulants, anticoagulants, antineoplastic and disinfectants. 相似文献
53.
为了探讨黑臭河道沉积物可转化态氮(TF-N)的赋存对上覆水的影响,以典型黑臭水体——南淝河为研究对象,采用连续提取的方法将沉积物中可转化态氮分为离子交换态氮(IEF-N)、弱酸浸提态氮(WAEF-N)、强碱浸提态氮(SAEF-N)和强氧化剂浸提态氮(SOEF-N),研究南淝河沉积物中可转化态氮形态受排口类型和沉积物理化性质的影响规律,及其与上覆水氮素含量之间的关系。结果表明:南淝河沉积物可转化态氮以TF-NO3--N为主,占TF-N的88.57%±6.13%,而TF-NH4+-N仅占TF-N的11.43%±6.13%;从赋存形态的角度看,南淝河沉积物中SOEF-N相对含量最高(57.48%±3.67%),WAEF-N次之(26.16%±3.10%),SAEF-N和IEF-N较少,其相对含量分别为10.30%±4.85%和6.05%±1.73%;沉积物中TF-NH4+-N含量受排口类型的影响较为敏感,且4种赋存形态氮含量受排口类型影响的规律各不相同。另外,pH值和有机质含量对IEF-N影响较大,而CEC影响着WAEF-N含量。上覆水中溶解有机氮(dissolved organic nitrogen,DON)含量与沉积物IEF-N含量之间的显著相关(P4+-N赋存含量越多,释放到上覆水体的可能性越大。研究结果表明黑臭水体是一个复杂的生态系统,调控沉积物可转化态氮形态给黑臭水体内源污染控制提供新思路。 相似文献
54.
55.
Anaerobic degradation of diethyl phthalate, di-n-butyl phthalate, and di-(2-ethylhexyl) phthalate from river sediment in Taiwan 总被引:5,自引:0,他引:5
We investigated anaerobic degradation rates for three phthalate esters (PAEs), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), and di-(2-ethylhexyl) phthalate (DEHP), from river sediment in Taiwan. The respective anaerobic degradation rate constants for DEP, DBP, and DEHP were observed as 0.045, 0.074, and 0.027 1/day, with respective half-lives of 15.4, 9.4, and 25.7 days under optimal conditions of 30 °C and pH 7.0. Anaerobic degradation rates were enhanced by the addition of the surfactants brij 35 and triton N101 at a concentration of 1 critical micelle concentration (CMC), and by the addition of yeast extract. Degradation rates were inhibited by the addition of acetate, pyruvate, lactate, FeCl3, MnO2, NaCl, heavy metals, and nonylphenol. Our results indicate that methanogen, sulfate-reducing bacteria, and eubacteria are involved in the degradation of PAEs. 相似文献
56.
Seasonal Fluctuation in Heavy Metal Pollution in Iran´s Siahroud River - A Preliminary Study (7 pp) 总被引:1,自引:0,他引:1
Charkhabi AH Sakizadeh M Rafiee G 《Environmental science and pollution research international》2005,12(5):264-270
Background The management of its available water resources has become a key issue for Iran. During the last few decades, the water quality
of Siahroud River in the coastal plain of the Caspian Sea in Gilan Province in Northern Iran has significantly degraded. The
scarcity of water has been compounded by rapid population growth and increasing pollution from fertilizers, pesticides, and
municipal and industrial wastes. One of the sources of this degradation is the movement of heavy metals from the river's watershed
into the various water systems supported by the river, including the water system for Rasht City.
Methods To study the magnitude of heavy metal pollution in the Siahroud River, seven heavy metals including Zn, Cu, Pb, Cd, Mn, Fe,
and Ni were measured in duplicate from replicated water samples collected over five consecutive seasons and analyzed by Atomic
Absorption Spectrometry. In situ measurements of pH were taken with the samples and total organic carbon (TOC) was analyzed
by IR gas measurement.
Results The results demonstrated that four of the seven heavy metals including Pb, Fe, Cd, and Mn exceeded permissible safe levels
as established by the United States Environmental Protection Agency. Multivariate factor analysis suggested that industrial
land-use was the main contributing factor for the high levels of Fe and Mn in the Siahroud River, whereas, Cd was principly
from agricultural activities in the watershed. The data also suggested that pH and TOC had an important role in the behaviour
of Pb and Mn, and that the elevated levels of these two heavy metals in Siahroud River was the consequence of other anthropogenic
sources. Only negligible levels of Zn, Cu and Ni were detected. Finally, all the sampling stations were subjected to cluster
analysis. The results indicated that three different zones could be distinguished according to the levels of pollution. In
addition, it was shown that the urban areas did not have a significant impact on the heavy metal pollution in the river. This
observation stems from the fact that the data from the sampling stations before and after Rasht City were not significantly
different.
Recommendation . Preventive measures need to be undertaken in the land-use systems and watersheds of the Siahroud River to reduce the pollution
levels of Pb, Cd, Mn and Fe. 相似文献
57.
改善深圳河水质的补水方案及生态影响初步分析 总被引:3,自引:0,他引:3
深圳河旱季天然径流量小而污染负荷高,为了改善河流水质,在削减入河污染物的同时有必要采取补水措施。利用水质模型,计算了不同污水处理率下,分别以污水资源化再生水、珠江口海水和大鹏湾海水为补水水源时,深圳河达到基本不黑臭所需的补水量。讨论了补水方案对河流水质、盐度、水动力条件的改变及其对生态系统的影响。研究表明,引海水对河流生态系统的冲击不容忽视。而污水资源化是较优的补水方案。 相似文献
58.
随着环境问题的日益突出,环境保护以及环境治理越来越迫切,由于造成环境污染问题的因素特别多,在对污染原因没有明确了解的情况下,盲目的着手进行环境污染治理工作,将会很难达到预期的治理效果。因此,作者从环境污染治理工程管理入手,进一步探索导致环境污染问题日益严重的根本原因,并详细分析加强环境污染治理工程管理的有效方略,旨在提高我国环境污染治理工程管理水平。 相似文献
59.
江苏淮河流域工业点源负荷空间分布特征研究 总被引:2,自引:0,他引:2
搞清流域工业点源的空间分异特征,可为水环境整治与工业规划提供参考依据。采用工业污染源普查数据建立污染源信息数据库,在GIS技术、密度分析法与ESDA方法支撑下,探析江苏淮河流域工业点源与工业污染负荷空间格局与特征。结果显示:工业点源集聚于城市、县城及专业乡镇,污染行业地域分异现象显著,其中,河流、港口及临湖地区成为高负荷工业点源集聚地区,化工、造纸、化纤与医药等行业的工业集中于临海、临河及临湖地区,饮料制造业、副食品加工业点源集中于工业化水平较低的北部流域的少数乡镇,工业氨氮多数来自化工业。在不同工业化水平下,工业污染负荷空间差异大,南部流域负荷整体水平高于北部,北部流域高负荷区分布于少数乡镇与城区 相似文献
60.
The influence of anthropogenic activities,especially artificial dykes,on the coastal wetland landscape is now considered as a serious problem to the coastal ecosystem.It is important and necessary to analyze changes of coastal landscape pattern under the influence of artificial dykes for the protection and management of coastal wetland.Our study aimed to reveal the quantitative characteristics of the coastal wetland landscape and its spatial-temporal dynamics under the influence of artificial dykes in the Yellow River delta(YRD).It was analyzed by the methods of the statistical analysis of landscape structure,five selected landscape indices and the changes of spatial centroids of three typical wetland types,including reed marshes,tidal fiats and aquaculture-salt fields.The results showed that:(1)Reduction of wetland area,especially the degradation of natural wetlands,had been the principal problem since the dykes were constructed in the YRD.The dykes created conditions for the development of artificial wetlands.However,the new born artificial wetlands were still less than the vanished natural wetlands.(2)Compared with the open area,the building of artificial dykes significantly speeded up the changes of landscape patterns and the aggravation of the landscape fragmentation in the closed area.(3)The changes of area-weighted centroids of three typical wetland landscapes were greatly affected by dykes,and the movement of the centroid of the aquaculture-salt field was very sensitive to the dykes constructed in the corresponding period. 相似文献