共查询到19条相似文献,搜索用时 109 毫秒
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对日照市不同类型地下水总硬度与溶解性总固体监测数据进行分析并建立二者之间的回归方程。分析结果表明:四种类型地下水总硬度与溶解性总固体之间存在着良好的相关性:碳酸盐类裂隙岩溶水、碎屑岩类孔隙裂隙水、基岩裂隙水和松散岩类孔隙水的总硬度与溶解性总固体的相关系数分别为0.981,0.973,0.971和0.953。 相似文献
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矿化度是地下水化学成份测定的重要指标,在环境监测中,用重量法测定矿化度是目前普遍采用的方法。其缺点主要为费时,繁琐,耗电。本文通过测定洛阳市地下水的电导率,分析对比电导率与矿化度的关联,并进一步用回归方程确定电导率与矿化度之间的数量关系,探索出用电导率法间接测定地下水矿化度,具有快速,经济,准确的优点。 相似文献
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根据EDTA滴定法测定水质总硬度的实践经验,对EDTA滴定法进行改进,该改进方法和标准方法通过地表水、地下水以及总硬度标准样品的比对测定,实验证明改进方法测定结果准确、可靠,操作更加简便、快捷。 相似文献
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在宁夏灌区选择设施菜田(n=4)和水旱轮作大田(n=4),通过田间多点取样观测和室内分析的方法,研究了2种类型农田土壤氮素累积与分布特点,以及其迁移对浅层地下水的影响。结果表明,设施菜田0~150 cm土壤剖面溶解性总氮(TSN)、硝态氮(NO3--N)和溶解性有机氮(SON)含量都显著高于大田,前者分别是后者的1.5~5.6、1.5~3.4倍和1.6~9.8倍。设施菜田土壤氮素主要累积在0~5 cm和5~20 cm土层,而大田主要在40~100 cm土体。设施菜田和大田土壤溶解性总氮占全氮比例分别在5.4%~11.5%和2.2%~4.9%之间,前者的淋失风险较高。设施菜田各形态氮素累积量表现为SON>NO3--N>NH4+-N,大田为NO3--N>SON>NH4+-N。设施菜田浅层地下水中TSN、NO3--N和SON含量也都显著高于大田,前者平均含量分别是后者的9.5、13.8倍和7.0倍。因此,硝态氮和溶解性有机氮都是2种类型农田氮素累积的主要形态,也是浅层地下水污染的重要来源。 相似文献
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为了更好地了解眉山市东坡区主城区降水的化学组成特征,本文于2013年在东坡区环境监测站所在点采集到32场降水,并采用离子色谱仪、原子吸收分光光度计以及流动注射分析仪等分析降水中水溶性无机离子组份浓度,同时使用电导率仪测定降水的电导率,通过对这些数据的分析,总结得出:降水电导率加权年均值为100μs/cm,加权年均总离子浓度为982.21μeq/L,这两数的值均高于国内部分主要城市。另外,降水中主要组份依次是SO2-4、Ca2+、NO-3和NH+4,四者占总离子浓度的87%。NO-3/SO2-4质量浓度比的年均值为0.27,远小于1,说明本地区降水污染主要来自固定污染源。最后使用SPSS 19.0软件对降水中主要水溶性无机离子浓度进行相关性分析,推断出某些离子可能来自相同的污染源。 相似文献
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有机氯农药监测分析与其它监测分析一样,要求具备有均匀性、稳定性的标准参考物质或工作参考物质。如何研制液体和固体有机氯农药标准参考物质或工作参考物质,国内刊物中未见报导。研制农药六六六、滴滴涕标准试样,把它们配入有机溶剂(如石油醚、苯)中和固体(如面粉、土壤)中,均匀性及稳定性如何?降 相似文献
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Understanding of groundwater salinity using statistical modeling in a small tropical island,East Malaysia 总被引:1,自引:0,他引:1
Sarva Mangala Praveena Mohd Harun Abdullah Kawi Bidin Ahmad Zaharin Aris 《The Environmentalist》2011,31(3):279-287
This paper presents an understanding of groundwater salinity by identification of effective factors using chemometric methods
(cluster analysis and multiple linear regressions) in Manukan Island, Sabah. Local groundwater and environmental properties
were used to explore the effective factors of groundwater salinity. Cluster analysis showed salinity and chloride illustrated
the highest similarities. Electrical conductivity and total dissolved solids were also grouped in the same cluster. Seawater
is the only chloride source in groundwater of Manukan Island demonstrated an indication of seawater mixing in freshwater.
It is an effect of upward movement of the seawater by pumping activities. Precipitation and evapotranspiration (environmental
condition) with hydraulic heads were clustered together to show that they also influence salinity concentration in groundwater.
Multiple linear regressions showed descending order of the factors from chloride (the largest contribution) to evapotranspiration
(the smallest contribution) and illustrated the contribution to groundwater salinity in Manukan Island. The integrated results
using chemometric methods have provided a way to identify the effective factors on groundwater salinity. This similar approach
and resulting equation can be applied in other small tropical islands with alike hydrogeological condition and limited information
available for a better understanding of its groundwater salinity. 相似文献
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吹脱法应用于低浓度废水处理,可有效去除水中的溶解性气体和挥发性油类,同时还可增加水中的溶解氧,为进一步的生物处理创造有利条件。利用现场动态实验对影响除油的因素进行了试验研究,确定最佳处理条件为:气水比5∶1、淋水密度5.0m3/(m2·h),实验表明在最佳运行状态下,吹脱法对地下水中油类物质的去除率能够达到50%,还能去除水中的铁、氨氮等污染物质,是一种非常有效的预处理方法。为了弄清目前炼油厂废水的处理水平,通过对三个典型炼油废水处理厂的调查,分别对其处理流程、处理效果、采用的主要处理药剂及处理工艺进行了介绍,分析了每套处理设施的长处以及与先进设施对比存在的不足。 相似文献
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Ambient water quality and bacterial populations in the water resources of Pulau Perhentian, a Marine Park of Malaysia, were studied during a peak tourist arrival, off-monsoon period. The overall water and bacteriological quality of swimming/boating sites in the island is at an acceptable condition, although the conductivity (0.88–60 mS m–1) due to high dissolved solid concentrations is slightly high, when compared with the recommended standard and published guidelines for the protection/maintenance of recreation water and its aesthetic enjoyment (Universiti Malaya, Department of Environment, Malaysia, 1986). However, the bacteriological quality of the drinking/bathing water wells is poor, with faecal coliform counts (2 up to 1,600 MPN per 100 ml sample water) exceeding the permissible levels defined for raw water supplies (with or without treatment). This suggests that the groundwater, seepage and run-off into the wells is contaminated. Contrary to the belief of the water users being interviewed in a social survey, the untreated drinking/bathing water is not bacteria-free. The excessive counts are attributable to deoxygenated conditions (12–42 percent corresponding to 0.9–3.3 mg l–1) prevailing in the wells, high total suspended solids (up to 202 mg l–1) which promote bacterial growth, lack of adequate sewerage systems to receive effluents from lavatories of dwellings, chalets and resorts, as well as the lack of centralised water treatment plants and storage tanks to cope with water scarcity and waterway contamination. 相似文献
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Lekan Taofeek Popoola 《环境质量管理》2019,29(1):169-179
This study investigated the quality of groundwater collected from two industrial and residential locations, each within the Lagos metropolis. Prescribed standard procedures of the American Public Health Association (APHA) were used to measure the physicochemical parameters of each of the groundwater samples, which include pH, electrical conductivity (EC), dissolved oxygen, total dissolved solids (TDS), biological oxygen demand, chemical oxygen demand; the anions chloride (Cl?), nitrate (NO3?), sulfate (SO4?), and phosphate (PO4?); and heavy metals copper (Cu), zinc (Zn), lead (Pb), manganese (Mn), iron (Fe), cobalt (Co), cadmium (Cd), and chromium (Cr). Based on the laboratory analysis, the physicochemical parameters that were measured were within the permissible ranges specified by the World Health Organization and the Nigerian Standard for Drinking Water Quality Standards Organization of Nigeria (SON), except for pH, TDS, EC, Pb, Mn, and Fe for groundwater samples from the industrial locations and for pH, Pb, Mn, and Fe for residential locations. The elevated concentrations of TDS and EC reported for groundwater samples from industrial locations were attributed to the heavy discharge of effluents from nearby industrial treatment plants as well as the dissolution of ionic heavy metals from industrial activities involving the use of heavy machines. Statistical analysis using Pearson's correlation revealed the physicochemical parameters to be moderately and strongly correlated with one another at either p < .05 or < .01. In conclusion, groundwater samples from residential locations are more suitable for drinking than those from industrial locations. 相似文献
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John M. Peckenham Sarah K. Peckenham 《Journal of the American Water Resources Association》2014,50(6):1477-1487
Student scientists have analyzed groundwater used for drinking water in rural areas to understand groundwater quality. This was part of a greater effort to understand risks to drinking water. The data produced by middle level and high school students have not been accepted by experts because of concerns about method and student accuracy. We assessed the inherent errors associated with method accuracy, student precision, and sample variability to establish bounds for attainable trueness in water analyses. Analytical test kits and probes were evaluated for the determination of pH, conductivity, chloride, hardness, iron, total soluble metals, and nitrate. In terms of precision, all methods met or exceeded design specifications. Method trueness was variable and in general ranged from good to poor depending on method. A gage reproducibility and repeatability analysis of instrumental methods (pH and conductivity) partitioned the variances into student error (12‐46%), instrumental error (8‐21%), and random error (45‐68%). Overall, student‐generated data met some of the quality objectives consistent with the method limitations. Some methods exhibited a systematic bias and data adjustment may be necessary. Given good management of the student analyst process, it is possible to make precise and accurate measurements consistent with the methods specifications. 相似文献
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This study examined the spatial-temporal variations and factors influencing the management of groundwater along a section of the Bagmati river corridor in the Kathmandu valley (Nepal). The results showed that rural areas were less polluted than urban areas. In urban areas, the biochemical oxygen demand (BOD), total nitrogen (TN) and total phosphorus (TP) concentrations ranged from 8.41 to 29.74 mg/L, 6.7 to 128.96 mg/L and 0.06 to 1.5 mg/L, respectively. In rural areas, the BOD, TN and TP concentrations ranged from 0.78 to 18.25 mg/L, 4.8 to 11.56 mg/L and 0.07 to 0.65 mg/L, respectively. The level of organics was higher in the pre-monsoon season, while the level of nutrients was higher in post-monsoon season. A comparison of the groundwater and surface water in the upstream rural areas revealed that the TP concentration was higher in the groundwater than in the surface water, which was attributed to the sorption of phosphorus on iron, aluminum or calcium compounds contained in the surface water, which depends upon the temperature, pH and dissolved oxygen. In urban areas, a few wells were found at groundwater levels lower than the corresponding surface water levels and were subjected to a high risk of pollution. Overall, these findings reinforce the notion that the management of surface and ground waters in an integrated approach is essential for attaining sustainable development of groundwater systems. 相似文献
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Xianjun Xie Yanxin Wang Junxia Li Chunli Su Mengyu Duan 《Journal of the American Water Resources Association》2013,49(2):402-414
Abstract: Analyses of major elements, environmental isotope ratios (δ18O, δ2H), and PHREEQC inverse modeling investigations were conducted to understand the processes controlling the salinization of groundwater within the Datong Basin. The hydrochemical results showed that groundwater with high total dissolved solid (TDS) concentrations was dominated by sodium bicarbonate (Na‐HCO3), sodium chlorite (Na‐Cl), and sodium sulfate (Na‐SO4) type waters, whereas low‐TDS groundwater from near mountain areas was dominated by calcium bicarbonate (Ca‐HCO3) and magnesium bicarbonate (Mg‐HCO3) type waters. The characterization of the major components of groundwater and PHREEQC inverse modeling indicated that the aluminosilicate hydrolysis, cation exchange, and dissolution of evaporites (halite, mirabilite, and gypsum) governed the salinization of groundwater within the Datong Basin. The environmental isotope (δ18O, δ2H) and Cl?/Br? ratios revealed the impact of fast vertical recharge by irrigation returns and salt‐flushing water on the groundwater salinization. According to the analyses of major hydrochemical components and PHREEQC inverse modeling, evaporite dissolution associated with irrigation and salt‐flushing practice was probably the dominant controlling factor for the groundwater salinization, especially in the central part of the basin. Therefore, groundwater pumping for irrigation and salt‐flushing should be controlled to protect groundwater quality in this area. 相似文献
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van der Salm C van den Toorn A Chardon WJ Koopmans GF 《Journal of environmental quality》2012,41(1):229-241
In flat areas, transport of dissolved nutrients by water through the soil matrix to groundwater and drains is assumed to be the dominant pathway for nutrient losses to ground- and surface waters. However, long-term data on the losses of nutrients to surface water and the contribution of various pathways is limited. We studied nutrient losses and pathways on a heavy clay soil in a fluvial plain in The Netherlands during a 5-yr period. Average annual nitrogen (N) and phosphorus (P) losses to surface water were 15.1 and 3.0 kg ha(-1) yr(-1), respectively. Losses were dominated by particulate N (50%) and P (70%) forms. Rapid discharge through trenches was the dominant pathway (60-90%) for water and nutrient transport. The contribution of pipe drains to the total discharge of water and nutrients was strongly related to the length of the dry period in the preceding summer. This relationship can be explained by the very low conductivity of the soil matrix and the formation of shrinkage cracks during summer. Losses of dissolved reactive P through pipe drains appear to be dominated by preferential flow based on the low dissolved reactive P concentration in the soil matrix at this depth. Rainfall occurring after manure application played an important role with respect to the annual losses of N and P in spring when heavy rainfall occurred within 2 wk after manure application. 相似文献