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1.
内蒙古乌梁素海水质时空分布特征   总被引:5,自引:0,他引:5  
李兴  杨乔媚  勾芒芒 《生态环境》2011,(8):1301-1306
将地质统计学理论与地理信息系统相结合对乌梁素海富营养化指标、有机污染指标和盐化污染指标进行了kriging空间插值,结果表明:从时间角度分析,冬季总氮浓度、总磷浓度、化学需氧量质量浓度明显高于其他季节;叶绿素a质量浓度浓度冬季最低;时空电导率平均值在4.0 ms.cm-1左右波动。从空间角度分析,总氮浓度、总磷浓度、叶绿素a质量浓度呈现出由北向南递减的趋势;夏秋季化学需氧量空间分布与春冬季节相反;冬季电导率空间分布与其他季节明显不同。从浓度大小分析,乌梁素海复合污染已十分严重。  相似文献   

2.
将地质统计学理论与地理信息系统相结合对乌梁素海富营养化指标、有机污染指标和盐化污染指标进行了kriging空间插值,结果表明:从时间角度分析,冬季总氮浓度、总磷浓度、化学需氧量质量浓度明显高于其他季节;叶绿素a质量浓度浓度冬季最低;时空电导率平均值在4.0 ms.cm-1左右波动。从空间角度分析,总氮浓度、总磷浓度、叶绿素a质量浓度呈现出由北向南递减的趋势;夏秋季化学需氧量空间分布与春冬季节相反;冬季电导率空间分布与其他季节明显不同。从浓度大小分析,乌梁素海复合污染已十分严重。  相似文献   

3.
滇池流域土地利用景观空间格局对水质的影响   总被引:3,自引:0,他引:3  
曹晓峰  孙金华  黄艺 《生态环境》2012,21(2):364-369
选用综合水质评价方法,对滇池流域进行水质评价。选取斑块数量(NP)、斑块密度(PD)、最大斑块指数(LPI)、最大形状指数(LSI),作为表征景观空间格局的参数,来分析流域优势斑块对水质的影响。对水质评价结果与景观指数进行相关性分析得出:居民点及工矿用地斑块数量越多、形状越不规则,有利于延缓水质状况的恶化;耕地斑块越大,越集中,本身产生的面源污染浓度就越高,而流经耕地的径流中的污染物浓度则会因大斑块的吸附过滤作用而降低;林地斑块密度越大,对污染物的截留纳污作用就越大,而斑块越大,可能产生局限性,导致未流经林地的污染物直接进入河流而影响水质。  相似文献   

4.
巢湖沉积物中氮与磷赋存形态研究   总被引:18,自引:1,他引:18  
利用连续提取法研究巢湖沉积物中不同赋存形态P、N的组成和分布特征.结果显示,巢湖沉积物中总P含量为0.111~0.655 g·kg-1,平均0.358 g·kg-1,主要由无机P组成(65%~72%),赋存形态以铁结合态为主;巢湖沉积物中总N含量为0.220~0.922 g·kg-1,平均0.532 g·kg-1,以有机N为主,约占总N的94.7%.有机N含量与有机指数等指标显示,巢湖处于清洁与尚清洁状态.湖泊沉积物中有机质、总N、总P间相关分析表明,湖泊营养物质来源具同一性趋势;有机C/N比值的研究结果显示,有机质主要来源于陆源.  相似文献   

5.
应用荧光定量PCR技术对蓝藻水华暴发期间太湖和巢湖水体中产毒微囊藻和总微囊藻种群丰度的空间分布进行了研究.分别以微囊藻毒素合成基因基因家族成员mcyD和小核糖体16S rDNA序列构建定量PCR标准曲线,研究产毒微囊藻和总微囊藻种群丰度.结果表明:太湖和巢湖微囊藻种群由产毒微囊藻和非产毒微囊藻组成;蓝藻水华暴发期间,微囊藻种群组成及其丰度分布具有明显的空间差异性:太湖产毒微囊藻种群丰度为9.89×104~4.51×106 copies mL-1,产毒微囊藻占总微囊藻种群的比例为20.5%~38.1%;巢湖产毒微囊藻种群丰度为4.12×104~5.44×106 copies mL-1,其占总微囊藻种群的比例为8.4%~96.6%.总的来说,富营养化严重的湖区总微囊藻和产毒微囊藻种群丰度较高,产毒微囊藻占总微囊藻种群的比例也较高.图7表3参29  相似文献   

6.
灰色聚类法综合评价滴水湖水系环境质量   总被引:2,自引:0,他引:2  
将滴水湖水系看作一个灰色系统进行研究,利用灰色聚类理论,以地表水环境标准和富营养化分级标准为基础建立灰类评价体系,确定聚类指标的隶属度和标准灰类的权重,得到各聚类指标对标准灰类的聚类系数,最大聚类系数关联的等级即水体质量等级。2010年,每2周1次对滴水湖水系11个监测点的溶解氧(DO)、化学需氧量(CODMn)、五日生化需氧量(BOD5)、总磷(TP)、总氮(TN)、氨氮(NH3-N)、透明度(SD)及叶绿素a(Chl.a)进行监测,取各指标的年均值,建立灰类评价系统。结果表明:滴水湖水源大治河及引水干道随塘河处水质属于Ⅳ类~Ⅴ类,呈富营养化和极度富营养化状态;闸外引水河芦潮引河段水质类型为Ⅲ类,为富营养化水平;闸内引水河道水质总体呈现富营养化状态,水质类型为Ⅲ类;滴水湖湖区水体质量良好,水质类型为Ⅲ类,呈中营养水平。  相似文献   

7.
巢湖生态系统中微量有机污染物的研究进展   总被引:1,自引:0,他引:1  
本文综述了目前巢湖生态系统中微量有机污染物研究的主要进展。巢湖微量有机污染物研究起步较晚,但发展较快。目前已研究的微量有机污染物包括有机氯农药、多氯联苯、多环芳烃、多溴联苯醚、邻苯二甲酸酯、全氟烷基酸类物质、四溴双酚A、抗生素和有机磷农药。研究内容主要包括水、大气、降尘、沉积物、悬浮物、水生生物等多介质分布、来源解析、跨界面迁移、归趋模拟与风险评估等方面。期望本文的综述,可以为巢湖微量有机污染物风险管理和水质改善提供重要决策支撑,对于在其他湖泊开展此类研究有所裨益。  相似文献   

8.
洞庭湖湿地水环境变化趋势及成因分析   总被引:2,自引:0,他引:2  
李有志  刘芬  张灿明 《生态环境》2011,(8):1295-1300
采用经典的Mann-Kendall非参数统计检测方法对洞庭湖湿地1991—2009年的水环境重要参数进行了变化趋势分析。结果表明,电导率、COD、BOD5、总氮、总磷、悬浮物呈显著上升趋势,色度、大肠杆菌、硝态氮、铵态氮呈不显著上升趋势,溶解氧呈显著降低趋势,pH、透明度呈不显著降低趋势。可见,洞庭湖湿地水质在逐步下降。突变趋势中,各参数突变时期及次数存在明显差别。除色度有1突变点位于显著信度线(p=0.05)与极显著信度线(p=0.01)之间,其余参数突变点均位于显著信度线之间。以色度和悬浮物突变最频繁,总氮和硝态氮变化最为平缓,其余参数居中。从各参数突变发生的时间可知,水质突变主要发生在1992—1998年。其次,对影响洞庭湖湿地水环境变化的因素进行了分析,得出"四水"流域及洞庭湖区工业污染、农业污染(化肥污染、农药污染、水产养殖、畜禽粪便)、生活污染等是导致水环境逐步恶化的主要原因。  相似文献   

9.
采用经典的Mann-Kendall非参数统计检测方法对洞庭湖湿地1991—2009年的水环境重要参数进行了变化趋势分析。结果表明,电导率、COD、BOD5、总氮、总磷、悬浮物呈显著上升趋势,色度、大肠杆菌、硝态氮、铵态氮呈不显著上升趋势,溶解氧呈显著降低趋势,pH、透明度呈不显著降低趋势。可见,洞庭湖湿地水质在逐步下降。突变趋势中,各参数突变时期及次数存在明显差别。除色度有1突变点位于显著信度线(p=0.05)与极显著信度线(p=0.01)之间,其余参数突变点均位于显著信度线之间。以色度和悬浮物突变最频繁,总氮和硝态氮变化最为平缓,其余参数居中。从各参数突变发生的时间可知,水质突变主要发生在1992—1998年。其次,对影响洞庭湖湿地水环境变化的因素进行了分析,得出四水流域及洞庭湖区工业污染、农业污染(化肥污染、农药污染、水产养殖、畜禽粪便)、生活污染等是导致水环境逐步恶化的主要原因。  相似文献   

10.
This paper tests the hypothesis that the expansion of improved drinking water supplies in rural India reduced household expenditure on water quality, offsetting some of the quality benefits from source protection. I estimate demand for in-home treatment using geological characteristics to predict a household's drinking water source. The probability of treatment and in particular boiling reduces by 18–27 percentage points in response to source protection, offsetting 4% of the water quality gains and saving households 0.5–1% in monthly expenditure. Behavioral choices partly counteract the water quality gains from source protection.  相似文献   

11.
Emission trading is one of the most effective alternatives to controlling water pollution. Water environmental functional zone (WEFZ) is used to determine the water quality standard and identify the zone boundary for each river or reach. In this study, a new emission trading scheme was addressed based on WEFZ, accounting for both the temporal dimension and water quality control. A temporal factor of emission trading was proposed based on variations in the environmental capacity within a year by dividing the year into three periods, including high, normal, and low periods of environmental capacity. During each period, emission trading was implemented exclusively. A water quality-control scheme was suggested based on the water quality requirement in the water functional zone, in which the water quality at the downstream boundary of the zone was required to meet the water standard following auto-purification in the stream. Two methods of calculating water quality control are addressed for point-source pollution and non-point-source pollution. The calculated temporal dimension and water quality control were located in Dongxi River of the Daning Watershed in the Three Gorges Watershed. The high period was during June, July, and August, the normal period was during April, May, September, and October, and the low period was during January, February, March, November, and December. The results from the water quality calculation demonstrated that the discharge of point-source and non-point-source pollutions led to an excess of common contaminants at the downstream boundary of WEFZ. The temporal and spatial factors above should be incorporated into the emission trading scheme based on WEFZ.  相似文献   

12.
• The concentrations of 13 heavy metals in Taihu Lake were analyzed. • Aquatic vegetables intake was first included in deriving human health AWQC. • The human health AWQC for 13 heavy metals in Taihu Lake were derived. • Human health risk assessment for 13 heavy metals were conducted in Taihu Lake. Heavy metals are widely concerning because of their toxicity, persistence, non-degradation and bioaccumulation ability. Human health ambient water quality criteria (AWQC) are specific levels of chemicals that can occur in water without harming human health. At present, most countries do not consider the effects of aquatic vegetables in deriving human health AWQC. Therefore, the intake of aquatic vegetables (Brasenia schreberi) was added to the derivation of human health AWQC and a health risk assessment for 13 heavy metals in Taihu Lake. The human health AWQC (consumption of water, fish and aquatic vegetables) values of 13 heavy metals ranged from 0.04 (Cd) to 710.87 μg/L (Sn), and the intake of B. schreberi had a very significant effect on the human health AWQC for Cu, with a more than 62-fold difference. The hazard quotients of As (2.8), Cd (1.6), Cr (1.4) and Cu (4.86) were higher than the safe level (HQ= 1), indicating that As, Cd, Cr and Cu in Taihu Lake posed a significant health risk. Sensitivity analysis showed that the contribution rate of B. schreberi intake to the human health risk from Cu was 91.6%, and all results indicated that the risk of Cu in B. schreberi to human health should be of particular concern. This study adds the consideration of aquatic vegetable consumption to the traditional method of human health AWQC derivation and risk assessments for the first time, and this approach can promote the development of risk assessments and water quality criteria.  相似文献   

13.
14.
The implementation of the European Water Framework Directive requires reliable tools to predict the water quality situations in streams caused by planned land use changes at the scale of large regional river basins. This paper presents the results of modelling the in-stream nitrogen load and concentration within the macro-scale basin of the Saale river (24,167 km2) using a semi-distributed process-based ecohydrological dynamic model SWIM (Soil and Water Integrated Model). The simulated load and concentration at the last gauge of the basin show that SWIM is capable to provide a satisfactory result for a large basin. The uncertainty analysis indicates the importance of realistic input data for agricultural management, and that the calibration of parameters can compensate the uncertainty in the input data to a certain extent. A hypothesis about the distributed nutrient retention parameters for macro-scale basins was tested aimed in improvement of the simulation results at the intermediate gauges and the outlet. To verify the hypothesis, the retention parameters were firstly proved to have a reasonable representation of the denitrification conditions in six meso-scale catchments. The area of the Saale region was classified depending on denitrification conditions in soil and groundwater into three classes (poor, neutral and good), and the distributed parameters were applied. However, the hypothesis about the usefulness of distributed retention parameters for macro-scale basins was not confirmed. Since the agricultural management is different in the sub-regions of the Saale basin, land use change scenarios were evaluated for two meso-scale subbasins of the Saale. The scenario results show that the optimal agricultural land use and management are essential for the reduction in nutrient load and improvement of water quality to meet the objectives of the European Water Framework Directive and in view of the regional development plans for future.  相似文献   

15.
原位采集太湖流域典型平原河网地区农户化粪池排污口附近的表层土壤及化粪池出水,人工模拟研究区域典型降雨(夏季30 mm·次-1,冬季5mm·次-1)、气温(夏季27℃,冬季5℃)条件以及排污负荷[TN:(2.35±0.06) g·m^-2 ·d^-1,NH4+-N:(2.08±0.04)g·m^-2· d^-1,TP:(0.21±0.01)g·m^-2·d^-1,COD:(11.14±0.59)g·m^-2·d^-1],并进行室内模拟土柱试验,测算不同季节(夏季和冬季)、不同天气过程(雨前、雨天和雨后)排污口表层土壤对农村生活污水各类污染物的削减率并探讨其削减规律.结果表明:在季节差异上,雨前、雨天和雨后TN削减率均表现为夏季<冬季(P<0.05或P<0.001),NH4+-N削减率则均表现为夏季>冬季(P<0.01);雨前和雨后TP削减率表现为夏季>冬季(P<0.001),COD削减率无显著季节性差异;雨天TP和COD削减率则均表现为夏季<冬季(P<0.01或P<0.001).在天气过程差异上,夏季土壤TN削减率表现为雨后>雨前>雨天(P<0.01),夏季TP和COD削减率表现为雨前≈雨后>雨天(P>0.05,P<0.01),而夏季NH4+-N,冬季TN、NH4+-N、TP和COD削减率在不同天气过程之间无显著差异(P>0.05).据此划分,夏季雨前、雨天和雨后及冬季TN削减率分别为38.5%、-25.0%、46.0%和50.4%,夏季和冬季NH4+-N削减率分别为91.5%和85.5%,夏季雨天、夏季其余时间及冬季TP削减率分别为63.3%、93.1%和82.7%,夏季雨天及其余时间COD削减率分别为8.2%和66.2%.  相似文献   

16.
Cyanobacterial bloom events in South Taihu Lake cause serious water quality problems and disturb aesthetic view of lake’s environment. In this study, correlations between cyanobacterial blooms and hydro-meteorological factors, including water quality, temperature and precipitation were investigated. Results demonstrated that South Taihu Lake was heavily affected by cyanobacteria and the proliferation of cyanobacteria due to variations in hydro-meteorological factors and water quality conditions. Water quality parameters, including COD, NH3-N, TN and TP improved significantly since 2008 even at an elevated cyanobacterial bloom situation. Correlation analyses have shown that the development of cyanobacterial density and chlorophyll a concentration was sensitive to a wider temperature variation. The optimum temperature for cyanobacteria was 20°C, while extremely low and high temperatures were found to suppress their growth. Moreover, unusual rainfall patterns were measured during the study period (2003–2009), which showed an adverse impact on cyanobacterial development. Findings from this study suggested that seasonal lake’s water quality monitoring; suitable treatment of cyanobacterial blooms and strict policy implementation can solve the water quality issues in highly eutrophic lakes like Taihu.  相似文献   

17.
The concentration of selected inorganic chemicals was determined for 396 samples of bottled water, desalinated water, and groundwater used for drinking and domestic purposes in the United Arab Emirates (UAE). The objective of this study was to compare the concentrations of inorganic chemicals in different domestic water types used in the UAE with the World Health Organization (WHO) limits for drinking water. Results of the present study revealed a wide variation in the concentrations of major, minor, and trace inorganic chemicals in domestic water of the UAE. For example, the bottled water sold for drinking is depleted in major ions and the total dissolved solids (TDS) in some brands do not exceed 100 mg/l. On the other hand, some of the domestic water used may contain as much as 3,000 mg/l TDS, which is above the WHO recommended limit for drinking water (500–1,500 mg/l TDS). Similarly, while bottled water is almost free of trace ions and minor constituents, some natural groundwater may have concentrations higher than the WHO recommended limits for drinking water. The cause of this variation is related to the different water sources and the large number of companies producing and distributing drinking and domestic water. Moreover, it is clear that the current controls on domestic water quality in some areas, namely conformance of pH and electrical conductivity measurements with prescribed ranges of values, are currently inadequate. These two parameters are not enough to judge if water is suitable for drinking or not and some consumers may receive domestic water of uncertain quality.  相似文献   

18.
以第1次全国污染源普查为背景,针对太湖流域农村生活源产排污系数测算过程中监测点的设置、监测采样和数据分析等问题进行重点分析.基于自然环境分区与经济收入水平分级和突出重点、合理布局的原则设置太湖上游监测点,划分6个类型区共计15个监测点,分有下水和无下水农户2种情况进行监测点建设;具体分析了农村生活污水和生活垃圾的采样步骤,并设计了生活污水、垃圾现场采样记录表,以利于数据记录和分析处理的标准化;依据Grubbs准则和Dixon准则进行监测数据结果的数理统计,选取Grubbs准则进行监测数据最大值或最小值的异常值检验.  相似文献   

19.
基于多元统计的引黄水库沉沙条渠泥沙与水质的变异分析   总被引:1,自引:0,他引:1  
以济南市引黄供水鹊山水库沉沙条渠为研究对象,测定了9个断面(Y1—Y9)表层水体中的含沙量、总有机碳、总磷、总氮、叶绿素a等19个水质指标.运用主成分分析法和聚类分析法分别探讨水体的主要污染因子及监测断面的沿程归类,并通过室内模拟实验分析了泥沙对水体中N、P浓度的影响.结果表明,沉沙条渠中的水质总体特征以Ⅱ类水和Ⅲ类水为主,其中,超标水质指标为TN,达到劣Ⅴ类水标准,P为藻类生长的限制因子.19个水质指标可由6个主成分来反映,其贡献率分别为:F1(TN、NH3-N、NO3--N、NO2--N、总碱度、Br-、硫酸盐)34.41%,F2(含沙量、浊度、色度、电导率)22.78%,F3(pH和UV254)13.95%,F4(TP)6.280%,F5(CODCr)4.990%和F6(Chl-a)4.830%;9个监测断面归为4类,相应地整个沉沙条渠可划分为4个功能区:入渠布水区(Y1、Y2、Y3)、快速沉降区(Y4、Y5)、缓慢沉降区(Y6、Y7、Y8)和出水稳定区(Y9).此外,水质与泥沙关系的室内模拟实验表明,条渠来水的P浓度随着泥沙颗粒的沉降而降低,TP在0—15 h内快速下降,而后缓慢下降,30 h内基本达到平衡;而泥沙颗粒对水中N浓度基本没有影响.  相似文献   

20.
珠江水质和含氮消毒副产物的时空变化   总被引:2,自引:0,他引:2  
梁艳红  何洪威  周达诚 《环境化学》2012,31(9):1308-1314
研究区域是珠江广东省段的3条干流(西江、北江、东江)及交汇处(广州),目标是研究分析2年内29个采样点的常规水质指标的时空变化及溶解性有机氮(dissolved organic nitrogen,DON)对于消毒副产物生成势(specific disinfection byproduct formation potential,SDBPFP)的影响.结果表明,对于常规水质指标浓度而言,在时间上,西江、北江、东江三者基本无变化,但交汇处有稍微的变化,一般在7、10月份浓度偏高;在空间上,各干流及交汇处沿径流方向浓度呈逐渐增大趋势,且交汇处水质指标的浓度普遍高于干流.水体的PO34-浓度、总氮(total nitrogen,TN)浓度最高分别超出《国家地表水环境质量》Ⅴ类水质标准10倍、4倍.溶解性有机碳(dissolved organic carbon,DOC)浓度与UV254呈良好的线性关系,R2=0.901;但DON与卤乙腈(halogenacetonitrile,HANs)浓度的线性关系较差,R2为0.440.卤乙腈生成势(specific halogen acetonitrile formationpotential,SHANFP)与DOC/DON比值基本无线性关系.  相似文献   

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