首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
青山水库的浮游植物与营养类型评价   总被引:1,自引:0,他引:1  
共鉴定青山水库藻类58属101种,其中有多污水体指示种5种,α-中污水体指示种24种、β-中污水体指示种49种,寡污水体指示种21种。优势种为窄颗粒直链藻(Melosiragranulatavar.angustissima)、颗粒直链藻(M.granulata)和小颤藻(Oscillatoriatenuis)。浮游植物的细胞密度为8.53×107个/L,生物量为16.34mg/L,叶绿素a为16.86mg/m3。根据浮游植物群落结构和水化学分析结果,青山水库已属富营养型水体,并有继续发展的趋势,控制污染,保护水质已刻不容缓。  相似文献   

2.
在2014年6月至2015年5月,对以再生水为补水水源的天津临港生态湿地公园景观湖区的浮游藻类和水质指标进行逐月监测,应用典范对应分析(CCA)研究了浮游藻类与环境因子之间的关系,评价了湖区的水环境状况。结果表明:共鉴定出浮游藻类7门67属115种(包括变种),硅藻门种类最多,其次为绿藻门和蓝藻门,浮游藻类丰度范围为3.5×106~49×106cells·L~(-1),平均丰度为25.7×106cells·L~(-1),优势藻种主要为链状假鱼腥藻、梅尼小环藻、四尾栅藻、颤藻、项圈藻和卵形隐藻;多样性分析显示,藻类物种多样性一般,结合优势指示种评价水体为中污染富营养型水体;典范对应分析表明,水温、盐度、TN/TP等是影响临港再生水补水景观湖藻类群落结构的主要因素。  相似文献   

3.
本文讨论了兼性塘试验中浮游植物群落结构与水质的关系。结果表明:浮游植物群落的多样性指数(H′)与塘的有机负荷率、出水BOD_5和COD均呈负相关;在温度不变时,浮游植物群落的生态优势度与塘的有机负荷率呈正相关(r>0.90)。  相似文献   

4.
分别于2017、2018年的非冰封期(5—10月)对南海湖的浮游植物群落和环境因子进行了调查。共发现浮游植物7门80属157种(含变种),其中绿藻门种数最多,其次是硅藻门和蓝藻门,时间上7月最多、10月最少,空间上呈东高西低、南高北低的趋势。浮游植物密度为23.35×10~6~126.00×10~6个/L,平均值为66.78×10~6个/L。主要优势种有微小平裂藻(Merismopedia tenuissima)、水华束丝藻(Aphanizomenon flosaquae)和螺旋弓形藻(Schroederia spiralis)。南海湖水质总体处于中污染状态。冗余分析表明,TN、TP、pH和温度是影响浮游植物分布的主要环境因子,绿藻门与TN关系密切,蓝藻门与TP、温度关系密切,硅藻门与pH关系密切。  相似文献   

5.
里杜湖富营养化综合评价及预测   总被引:2,自引:0,他引:2  
根据里杜湖水库的水质监测及水文资料,选择评分法结合生物优势种评价法以及“源-效应”预测模型对里杜湖水库水质的营养状态进行综合评价及预测。结果表明:里杜湖水库水质已轻度富营养化,并有逐年加重的趋势。旨在正确评价和预测里杜湖水库营养状态,并为同类水库的营养状态评价及预测提供参考和借鉴,从而为水库水质管理及富营养化的控制提供科学依据。  相似文献   

6.
为比较水体中浮游植物群落对不同紫色母岩净化景观水体效果的指示作用。选取重庆地区分布面积较广的蓬莱镇组(S1)、沙溪庙组(S2)、飞仙关组(S3)和遂宁组(S4)4种不同紫色母岩,将其灭菌后加入未灭菌的取自西南大学崇德湖的景观水体中,进行生态缸构建。测定水体理化性质、微量元素以及浮游植物群落结构。结果表明:利用浮游植物密度和功能群对景观水体水质的指示作用与利用水体理化指标的评价结果一致,而利用浮游植物生物量对景观水体水质的指示作用与利用水体理化指标的评价结果不符;对各组生态缸中水体元素和浮游植物优势功能群进行PCA分析,结果发现,水体中的部分微量元素与浮游植物的优势功能群Wo和X1呈现相关性。实验表明,浮游植物密度和浮游植物功能群可用于指示景观水体水质;相比于对照组,4组紫色母岩生态缸水体中的微量元素Cu、Mg可能通过对优势功能群Wo的抑制作用降低水体富营养化程度,具体机理需进一步研究。  相似文献   

7.
基于聚类分析和水质标识指数的水质评价方法   总被引:11,自引:0,他引:11  
为探讨一种适用于大尺度、多断面和长时间的水质评价方法,用层次聚类分析将2006~2008年海河5个监测断面的165个水质样本分为20组,并用方差分析验证了结果的可靠性。用综合水质标识指数表示水质样本的综合特征,与单因子评价法相比,该方法充分考虑了最差水质因子的影响,避免了单因子评价法以偏概全的缺陷,且分辨率高。将评价结果分解到各断面,结果表明:密云水库、官厅水库和于桥水库的水质处于II~III类水之间,可满足作为饮用水水源水的要求,三岔口断面大部分时间为IV~V类水,张家口八号桥断面全年有6个月以上水质属于劣V类。  相似文献   

8.
北方干旱区水库具有防洪、灌溉、城市供水多种功能,其富营养化控制具有重要意义。以对汾河水库水质长期监测数据为基础,结合水动力模型、物质输移扩散模型及富营养化生命过程建立富营养化耦合模型,研究不同情景下水库流场特征及营养物质的时空分布规律。研究表明,水库部分区域已发生富营养化,且库区内污染物浓度超标范围较大,提出上游排放口污染物削减方案,为汾河水库乃至整个北方干旱地区水库的富营养化控制提供技术支持。  相似文献   

9.
饮用水功能区水环境健康风险阈值体系研究   总被引:1,自引:0,他引:1  
结合天津市饮用水功能区水环境现状,筛选出14种特征污染物,通过危害识别将其分为化学致癌物、非致癌有毒物和特殊物质3类。针对不同类别污染物建立健康风险评价模型,给出化学致癌物的致癌强度系数、非致癌有毒物参考剂量、人均寿命、不同年龄段人群日均饮水量和平均体重等参数,建立针对不同人群的饮用水功能区水质风险阈值体系。在此基础上,对天津市饮用水功能区——于桥水库进行水质风险进行评价。结果显示,于桥水库国控监测点位10个监测指标中,氨氮、挥发酚、汞、铅具有健康风险,4个指标的浓度均处于10-7的风险水平以下,说明于桥水库水环境健康程度较好,4个指标对成人及儿童的风险水平排序为铅氨氮汞挥发酚,重金属铅是主要健康风险污染物。  相似文献   

10.
为了解青西郊野公园建设过程中大莲湖水生态环境变化动态,分别于公园建设前(2014年)、建设过程中(2016年)及开园运营后(2017年)对大莲湖水质及浮游植物群落进行了调查监测。3个年度水体综合营养状态指数平均值分别为49.84、54.66、53.16,表明水体呈现轻度富营养化趋势;3个年度分别采集浮游植物106、98、78种,均以绿藻门种数最多;3个年度浮游植物丰度平均值分别为6.36×10~6、1.05×10~7、1.89×10~7个/L,呈逐年递增趋势;基于浮游植物多样性指数评价,3个年度大莲湖水体水质基本处于中污染水平。冗余分析表明叶绿素a(Chl-a)、透明度和TN是影响大莲湖浮游植物种类和丰度的重要环境因子,其中Chl-a和透明度对浮游植物种类有显著影响,TN和透明度对浮游植物丰度有显著影响。  相似文献   

11.
Pesticides in rainfall in Europe   总被引:1,自引:0,他引:1  
Papers and published reports investigating the presence of pesticides in rainfall in Europe were reviewed. Approximately half of the compounds that were analysed for were detected. For those detected, most concentrations were below about 100 ng/l, but larger concentrations, up to a few thousand nanograms per litre, were detected occasionally at most monitoring sites. The most frequently detected compounds were lindane (gamma-HCH) and its isomer (alpha-HCH), which were detected on 90-100% of sampling occasions at most of the sites where they were monitored. For compounds developed more recently, detection was usually limited to the spraying season. A classification of pesticides according to their deposition pattern is proposed.  相似文献   

12.
The aim of the study was to estimate copper (Cu) accumulation efficiency in whole-fruiting bodies of 18 edible and non-edible wild growing mushrooms collected from 27 places in the Wielkopolska Voivodeship. Mushrooms were collected each time from the same places to estimate the diversity in Cu accumulation between tested mushroom species within 3 consecutive years of study (2011–2013). The study results revealed various accumulation of Cu in the whole-tested mushroom fruiting bodies. The highest mean accumulation of Cu was observed in Macrolepiota procera (119.4 ± 20.0 mg kg?1 dm), while the lowest was in Suillus luteus and Russula fellea fruiting bodies (16.1 ± 3.0 and 18.8 ± 4.6 mg kg?1 dm, respectively). Significant differences in Cu accumulation between mushroom species collected in 2011 and in the two following years (2012 and 2013) were observed. The results indicated that sporadic consumption of these mushrooms was not related to excessive intake of Cu for the human body (no toxic influence on health).  相似文献   

13.
Mercury (Hg) is a highly toxic environmental contaminant and man-made emissions account for between a quarter and a third of total atmospheric levels. Point discharges, particularly coal-burning power stations, are major sources of atmospheric Hg and can result in marked spatial variation in mercury deposition and subsequent uptake by biota. The aims of this study were to quantify the extent to which major point and diffuse sources of atmospheric Hg emissions affected accumulation of Hg by biota throughout Galicia and Asturias, two of the major regions in northwest Spain. We did this by relating renal Hg concentrations in locally reared cattle (n=284) to the proximity of animals to point and diffuse sources of Hg emissions. Mercury residues in calf kidneys ranged between non-detected and 89.4 g/kg wet weight. Point discharges from coal-fired power plants in Galicia had the most dominant impact on Hg accumulation by calves in Galicia, affecting animals throughout the region and explaining some two-thirds of the variation in renal residues between animals located directly downwind from the plants. The effects of more diffuse emission sources on Hg accumulation in calves were not distinguishable in Galicia but were detected in cattle from neighbouring Asturias. The impact of both point and diffuse sources in elevating environmental levels of bioavailable Hg and subsequent accumulation by cattle extended to approximately 140-200 km downwind from source.  相似文献   

14.
Mercury in fish in Swedish lakes   总被引:5,自引:0,他引:5  
The aim of this work has been to try to obtain a picture of the past, present and future mercury situation in fish in Swedish lakes, to make an estimate of the number of lakes threatened by 'blacklisting', and to see if the data can be used to reveal anything about the impact of liming on the Hg content in pike. The register contains a broad set of data from 1456 lakes. The main results are as follows. Trend analyses indicate that the Hg content in 1-kg pike seems to increase with time. This is interesting since there has been a significant decrease in mercury emissions from Swedish industries during the last two decades. High Hg contents in 1-kg pike appear in a very characteristic pattern, linked to specific sources of Hg emission. The data indicate that old Swedish 'sins' are still causing a lot of problems. The factors governing the leakage of Hg from soils to water ought to be a very important topic for further studies. The Hg content in pike shows the highest correlation with the following parameters: Hg in surficial sediments, pH, distance from point source and water hardness, lake water alkalinity and conductivity, water retention time, size of drainage area and lake surface. A formula which provides the best possible degree of explanation (r2 = 0.78) has been derived. At present there are about 250 lakes 'blacklisted' in Sweden due to high Hg content in fish. Our data show that there are at least 9400 lakes that ought to be 'blacklisted' today. A successful liming operation will alter the chemical conditions in lakes and also decrease the Hg content in fish.  相似文献   

15.
A trend analysis of the sulphate concentration in Europe in the summer half-year was performed. Data from various measuring networks were analysed, but only stations with quality assured sampling methods and a record of more than 10 years were included in the study. 1978 served as the reference year for the trend, because in that year most stations started operation. The relatively dense network in Belgium provided the most valuable data, as evidenced by the fact that two sites at a distance of only 10 km apart correlated better than 95% over a month. The two sites also show a correlation of better than 90% over a season with two other stations at distances of 45 and 95 km. The relative decrease in summer-sulphate at the four stations in Belgium, as analysed by linear regression, was 3.3% per year which corresponds to an absolute decrease of 0.42 μgm−3 per year. In the Netherlands the average yearly decrease in summer-sulphate at two stations was 3.5% (−0.34 μgm−3). In other countries stations were further apart or only a single site wits in use, which limits the representativeness of the data. In northwestern Germany, a region with several monitoring stations, a yearly averaged decrease of 3.0% occurred. The lower absolute decrease (0.25 μgm−3) per year compared to that in the two neighbouring countries reflects the lower summer-time sulphate concentrations. In the remainder of Germany the average decrease was 1.6%. In South-Scandinavia the yearly relative decrease at two sites was 2.6% (0.13 μgm−3 absolute). There was no significant trend in the U.K. Al the Polish station the levels increased, it decreased at the Hungarian and Austrian station and remained constant at the Czechoslovakian site. Reasons for omission of the data from France from the trend analysis are discussed.  相似文献   

16.
We investigated the occurrence, source and exposure time of lead poisoning in whooper swans (Cygnus cygnus cygnus) and Bewick's swans (Cygnus columbianus bewickii) in Japan during the winters of 1984-1987. Concentrations of lead in various tissues and physiological evidence of lead shot in some birds indicated that lead shotgun pellets were the source of lead, and exposure occurred after the birds arrived in Japan. Mortality probably occurred within 30 days after exposure to, and retention of, lead shot in the gizzard.  相似文献   

17.
Residues of five pesticides in surface water were surveyed during 2001 and 2003 in the Traiguen river basin in Southern Chile. Simazine, hexazinone, 2,4-D, picloram herbicides and carbendazim fungicide were selected through a pesticide risk classification index. Six sampling stations along the river were set up based on agricultural and forestry land use. The water sampling was carried out before and after the pesticide application periods and in correspondence to some rain events. Pesticides were analyzed by HPLC with DAD detection in a multiresidue analysis. During 2001, in the first sampling campaign (March), the highest concentrations of pesticides were 3.0 microg l(-1) for simazine and hexazinone and 1.8 microg l(-1) for carbendazim. In the second sampling (September), the highest concentration were 9.7 microg l(-1) for 2,4-D, 0.3 microg l(-1) for picloram and 0.4 microg l(-1) for carbendazim. In the last sampling period (December), samples indicated contamination with carbendazim fungicide at levels of up to 1.2 microg l(-1). In sampling carried out on May 2003, no pesticides were detected. In October 2003, the highest concentrations of pesticides were 4.5 microg l(-1) for carbendazim and 2.9 microg l(-1) for 2,4-D. Data are discussed in function of land use and application periods of the products, showing a clear seasonal pattern pollution in the Traiguen river. Risk assessment for these pesticides was calculated by using a risk quotient (RQ = PNEC/PEC). For picloram the calculated RQ < was 0, which indicates that no adverse effects may occur due to the exposure to this herbicide in the Traiguen river basin. For 2,4-D, simazine, hexazinone, carbendazim RQ > 1, meaning that adverse effects could occur and it is necessary to reduce pesticide exposure in surface waters. It is recommended to continue with a pesticide monitoring program and the implementation of ecotoxicological testing with local and standardized species in order to consider the probability of effects occurrence, with less uncertainty. Thus, it will be more feasible to make some recommendations to regulatory agencies regarding the pesticide use.  相似文献   

18.
二(口/恶)(口/英)是世界公认的强致癌物质,对人体健康危害极大.近年来,大气中二(口/恶)(口/英)的研究已成为各国环境化学家研究的热点.本文总结了近年来国际上有关大气中二(口/恶)(口/英)研究的进展情况,以及所取得的主要研究成果,并在此基础上指出了我国目前研究中存在的问题及以后所应开展的工作.  相似文献   

19.
20.
Toxic metals are bioaccumulated by insectivorous mammals but few studies (none from Britain) have quantified residues in bats. We measured renal mercury (Hg), lead (Pb) and cadmium (Cd) concentrations in bats from south-west England to determine how they varied with species, sex, age, and over time, and if they were likely to cause adverse effects. Residues were generally highest in whiskered bats (Myotis mystacinus). Compared with other species, pipistrelle (Pipistrellus spp) and Natterer's bats (Myotis nattereri) had significantly lower kidney Hg and Pb concentrations, respectively. Renal Hg increased over time in pipistrelles but the contributory sources are unknown. Kidney Pb did not decrease over time despite concurrent declines in atmospheric Pb. Overall, median renal metal concentrations were similar to those in bats from mainland Europe and 6- to 10-fold below those associated with clinical effect, although 5% of pipistrelles had kidney Pb residues diagnostic of acute lead poisoning.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号