Evaluation of pollution load of Lahore Canal by quantification of various pollutants through physicochemical characterisation

The work describes the physicochemical analysis of the water samples collected from Lahore Canal to evaluate pollution load at different points of the canal. Different physical and chemical pollutants such as temperature, pH, electrical conductivity, total dissolved and suspended solids, turbidity, chlorides, sulphates, nitrates, oils and grease, dissolved oxygen, chemical oxygen demand and biological oxygen demand (BOD) were analysed. The data was analysed through analysis of variance, which showed that the p values for dissolved oxygen (DO), chemical oxygen demand (COD), BOD, electrical conductivity, total dissolved solid (TDS), total suspended solid (TSS), turbidity, oil and grease, sulphates, and nitrates are <0.05, while p value of temperature, pH, and chlorides are 1.000, 0.984, and 0.070, respectively, which are >0.05. Further regression analysis revealed that the simple line regression modal is fit for turbidity and TSS, electrical conductivity and TDS, COD and DO, BOD and DO, and BOD and COD. The studies reveal that Lahore Canal is receiving a considerable amount of physical and chemical pollutants at different points.     

Water Quality Changes in Chini Lake, Pahang, West Malaysia

A study of the water quality changes of Chini Lake was conducted for 12 months, which began in May 2004 and ended in April 2005. Fifteen sampling stations were selected representing the open water body in the lake. A total of 14 water quality parameters were measured and Malaysian Department of Environment Water Quality Index (DOE-WQI) was calculated and classified according to the Interim National Water Quality Standard, Malaysia (INWQS). The physical and chemical variables were temperature, dissolved oxygen (DO), conductivity, pH, total dissolved solid (TDS), turbidity, chlorophyll-a, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solid (TSS), ammonia-N, nitrate, phosphate and sulphate. Results show that base on Malaysian WQI, the water in Chini Lake is classified as class II, which is suitable for recreational activities and allows body contact. With respect to the Interim National Water Quality Standard (INWQS), temperature was within the normal range, conductivity, TSS, nitrate, sulphate and TDS are categorized under class I. Parameters for DO, pH, turbidity, BOD, COD and ammonia-N are categorized under class II. Comparison with eutrophic status indicates that chlorophyll-a concentration in the lake was in mesotrophic condition. In general water quality in Chini Lake varied temporally and spatially, and the most affected water quality parameters were TSS, turbidity, chlorophyll-a, sulphate, DO, ammonia-N, pH and conductivity.     

Radioactivity, Physical and Chemical Parameters of Underground and Surface Waters in Qua Iboe River Estuary, Nigeria

Radioactivity, physical and chemical parameters of underground boreholes and surface waters in the region of Qua Iboe River Estuary involved in oil production activities were measured. The physical and chemical parameters measured included pH, temperature, turbidity, and concentrations of total dissolved and suspended solids, dissolved oxygen, chemical and biochemical oxygen demand, oils and grease, salinity, hardness (carbonates and bicarbonates), chlorine, sulphide, and metal ions. The work reveals that the radioactivity, physical and chemical parameters determined for both the underground and surface waters are safely below the international permissible limits except that of carbonate (68.6 mg/d – 228.7 mg/l) and bicarbonate (22.9 mg/l – 76.3mg/l) which renders both sources of water hard. The exceedingly high concentration range of hydrogen sulphide (40 mg/l–440 mg/l) in both sources is also beyond the international limit of 0.05mg/l. The ammonium ion concentration (1.40–2.80mg/l) was determined to be slightly higher in both the underground and surface waters than the international limit of 0.5mg/l.     

南京市地表水溶解氧分布特征及低氧成因初探——以外秦淮河七桥瓮为例

于2018—2021年对南京市及国考断面七桥瓮进行水质调查,分析其溶解氧变化特征,采用水质水量联合评价及皮尔逊相关分析法,并结合水文气象等相关信息,对南京市地表水溶解氧分布特征及国考七桥瓮断面低氧成因进行研究分析。结果表明,南京市地表水溶解氧浓度夏季最低,中心主城区及附近区域溶解氧浓度均相对较低。七桥瓮断面溶解氧浓度在2.25~11.07 mg/L,其中5—9月溶解氧易出现超标波动。溶解氧浓度昼间高于夜间,与pH值呈正相关关系,与水温、高锰酸盐指数、氨氮、总磷均呈负相关关系。水温和上游来水带入的耗氧污染物是七桥瓮断面溶解氧偏低的主要成因,其中,溶解氧浓度与水温相关性最为显著。研究结论可为七桥瓮断面稳定达标提供基础支撑,为秦淮河流域精准治污提供技术依据,为南京市水环境多源同治提供治理思路。     

Physicochemical quality of an urban municipal wastewater effluent and its impact on the receiving environment

The physicochemical qualities of the final effluents of an urban wastewater treatment plant in South Africa were assessed between August 2007 and July 2008 as well as their impact on the receiving watershed. The pH values across all sampling points ranged between 6.8 and 8.3, while the temperature varied from 18°C to 25°C. Electrical conductivity (EC) of the samples was in the range of 29–1,015 μS/cm, and turbidity varied between 2.7 and 35 NTU. Salinity and total dissolved solids (TDS) varied from 0.36 to 35 psu and 16 to 470 mg/L, respectively. The concentrations of the other physicochemical parameters are as follows: chemical oxygen demand (COD, 48–1,180 mg/L); dissolved oxygen (DO, 3.9–6.6 mg/L); nitrate (0.32–6.5 mg NO $_{3}^{-}$ as N/L); nitrite (0.06–2.4 mg NO $_{2}^{-}$ as N/L); and phosphate (0.29–0.54 mg PO $_{4}^{3-}$ as P/L). pH, temperature, EC, turbidity, TDS, DO, and nitrate varied significantly with season and sampling point (P?<?0.05 and P?<?0.01, respectively), while salinity varied significantly with sampling point (P?<?0.01) and COD and nitrite varied significantly with season (P?<?0.05). Although the treated effluent fell within the recommended water quality standard for pH temperature, TDS, nitrate and nitrite, it fell short of stipulated standards for other parameters. The result generally showed a negative impact of the discharged effluent on the receiving watershed and calls for a regular and consistent monitoring program by the relevant authorities to ensure best practices with regard to treatment and discharge of wastewater into the receiving aquatic milieu in South Africa.     

Analysis of the environmental impact on a stream: is only tannery to blame?

The contribution of wastewater from a tannery industry to the pollution of a stream was investigated. The main parameters studied were biochemical oxygen demand, chemical oxygen demand, chromium, dissolved oxygen, fecal and total coliforms, nitrogen, oils and greases, pH, phosphorous, sulfides, suspended solids, turbidity, and volatile solids. Three sampling points were located: (1) at the discharge point of tannery wastewater, (2) 50 m upstream, and (3) 80 m downstream of discharge point. Also was investigated the pollution at the stream source.     

Water Quality Assessment and Modeling of an Effluent-Dominated Stream, the Notwane River, Botswana

In an effort to assess current and future water quality of the only perennial river in southeastern Botswana, this study presents water quality monitoring and modeling results for the effluent-dependent Notwane River. The water quality along the Notwane River, pre- and post-implementation of secondary wastewater treatment, was compared and results demonstrated that water quality improved after the new wastewater treatment plant (WWTP) went online. However, stream standards for chemical oxygen demand, total dissolved phosphorous, and fecal coliform were exceeded in most locations and the critical dissolved oxygen (DO) reached concentrations of less than 4 mg L⁻¹. High dissolved P concentrations and intense macrophyte growth at the impounding ponds and at sites within 30 km of the effluent waste stream confluence suggest that eutrophication was a function of P release from the ponds. Results of DO modeling demonstrated that an unpolluted inflow at approximately 10 km downstream of the confluence was responsible for raising DO concentrations by 2.3 mg L⁻¹, while SOD was responsible for a decline in DO concentrations of 1.4 mg L⁻¹ at 6 km downstream of the confluence. Simulations also showed higher DO concentrations during winter months, when water temperatures were lower. Simulations, in which the distributed biochemical oxygen demand (BOD) loading from cattle excrement was decreased, produced nominal increases in DO concentrations. An increase in WWTP BOD loadings to projected 2020 values resulted in a 1.3 mg L⁻¹ decrease in the critical DO concentration. Furthermore, a decrease in treatment plant efficiency, from 94% to 70% BOD removal, produced critical DO concentrations and anoxia along much of the modeled reach. This has significant implications for Gaborone, especially if decreased WWTP efficiency occurs as a result of the expected future increase in pollutant loadings.     

太阳山湿地浮游植物优势功能群季节演替特征及驱动因子分析

为探明太阳山湿地浮游植物优势功能群季节演替规律及其主要驱动因子,于2019年4月(春季)、7月(夏季)、10月(秋季)和2020年1月(冬季)采样分析了太阳山湿地浮游植物的种类组成、优势种、丰度、生物量及季节变化,同时测定了水环境理化因子指标,采用冗余分析方法研究了浮游植物优势功能群的优势度、丰度与水环境因子之间的关系。结果表明:太阳山湿地浮游植物可分为22个功能类群;优势功能群的季节演替和空间分异特征明显,存在一定的规律性。春、秋、冬3个季节的浮游植物以硅藻门为主,夏季以绿藻门和蓝藻门为主。春季优势功能群主要为D、C、P,以硅藻门种类为主;夏季优势功能群主要为J、Lo、TC、M、H1,以硅藻门、绿藻门、蓝藻门种类为主;秋季优势功能群主要为D、S1、MP,以硅藻门、绿藻门种类为主;冬季优势功能群主要为D、X3,以硅藻门种类为主。影响太阳山湿地浮游植物优势功能群季节演替的水环境因子有水温(WT)、pH、溶解氧(DO)、透明度(SD)、盐度(Sal)、氮磷营养元素含量、化学需氧量(COD_Cr)和高锰酸盐指数(COD_Mn)。4个湖区浮游植物优势功能群的时空差异与水环境因子密切相关,其中,西湖区浮游植物优势功能群的季节演替驱动因子为pH、DO、WT、总磷(TP),东湖区为pH、DO、WT、氮磷营养元素含量,南湖区为pH、DO、COD_Cr、五日生化需氧量(BOD₅),小南湖区为pH、DO、WT、BOD₅、COD_Cr、TP。pH、DO、WT、BOD₅、SD等水环境因子的季节差异以及TP、TN、氨氮(NH₃-N)、COD_Mn等水环境因子的湖区差异是太阳山湿地浮游植物优势功能群出现季节演替的主要原因。     

浙江近岸海域春季表层溶解氧饱和度分布及影响因素

根据2014年春季对浙江省近岸海域溶解氧的调查结果,结合现场的温度和盐度,得出溶解氧饱和度的平面分布,并在此基础上探讨了饱和度与温度、盐度、化学需氧量、浮游植物丰度之间的关系。结果显示,浙江省近岸海域溶解氧饱和度范围为92.1%~120%,均值为100%。总体呈西部沿岸低,东部外海高的平面分布趋势。溶解氧饱和度高值区与浮游植物丰度的高值区一致。低饱和区域化学需氧量含量基本高于1 mg/L。陆源径流和有机物质耗氧分解是沿岸低饱和区域主要控制因素,外海水和浮游植物光合作用是高饱和区域主要控制因素。径流和外海水对有机物质分解和浮游植物光合作用有一定的调控作用。     

Evaluation of Water Quality Management Alternatives to Control Dissolved Oxygen and Un-ionized Ammonia for Ravi River in Pakistan

Different water quality management alternatives, including conventional wastewater treatment, transportation of wastewater, flow augmentation, low-cost treatment with reuse, and wetlands, are evaluated by using a verified dissolved oxygen (DO) model for the Ravi River. Biokinetic rate coefficients of the Ravi River for both the carbonaceous and nitrogenous oxygen-demanding wastes are adjusted, keeping in view the type and level of wastewater treatment. The conventional activated sludge process with nitrification comes out to be the most expansive alternative to meet the DO standard of 4 mg/L. Additional treatment cost is required to maintain un-ionized ammonia levels <0.02 mg/L, which corresponds to achieving treatment levels of 5 mg/L of DO in the river. Under critical low-flow conditions (i.e., minimum average seven consecutive days) of 9.2 m³/s, a flow augmentation of 10 m³/s can reduce 30 % of the cost with conventional wastewater treatment. Transportation of wastewater from the city of Lahore is a cost-effective alternative with 2.5 times less cost than the conventional process. Waste stabilization ponds (WSP) technology is a low-cost solution with 3.5 times less cost as compared to the conventional process. Further reduction in pollution loads to the Ravi River can be achieved by reusing WSP effluents for irrigation in the near proximity of Lahore along the Ravi River. The study results show that, for highly polluted rivers with such extreme flow variations as in case of the Ravi River, meeting un-ionized ammonia standards can reduce the efforts required to develop carbonaceous biochemical oxygen demand-based waste load allocations.     

Environmental assessment of water-courses of the Turvo Limpo River basin at the Minas Gerais State, Brazil

A study was performed to evaluate the environmental contamination in the Turvo Limpo River basin which receives effluent discharges from domestic (residential and commercial) activities. The watercourses examined were the São Bartolomeu Stream, Turvo Sujo River, and Turvo Limpo River, located in the Minas Gerais State, Brazil. Water samples were collected at the river-side and analyzed for evaluation of pollutant inputs. The pH, temperature, electrical conductivity, redox potential (Eh), dissolved oxygen (DO), total and settleable solids, visual color, hardness, chemical oxygen demand (COD), biochemical oxygen demand (BOD), chloride, total phosphate, total nitrogen, ammonia nitrogen, nitrate, total coliforms and E. coli, as well as the Cd, Pb, Cu, and Zn speciation were determined in the watercourses. The data obtained were compared with those of the Brazilian Environmental Standards and with data from non-contaminated areas. River water characteristics in some sites were far from the limit values established for superficial waters with satisfactory quality. For instance, the BOD values reached 411 mg L^?1 for a maximum limit of 10.0 mg L^?1, while the ammonia nitrogen concentration reached 28 mg L^?1 for a maximum limit of 13.3 mg L^?1. Some sites showed E. coli values above those of non-contaminated regions. Besides the effects of sewage discharges into the water-courses, agriculture activities and the use of the area for cattle husbandry influenced the quality of the river waters, for instance, the pH of a spring-water sample reached the value of 4.3. The São Bartolomeu Stream has been contributing to the deterioration of the water quality of the Turvo Sujo River, while the Turvo Limpo River has also been affected by anthropogenic discharges in the Turvo Sujo River. The speciation of Cd, Cu and Pb showed that these metals were mainly found in the particulate fraction (i. e., associated with the suspended material). Fifty five percent of the water samples showed labile Zn concentrations greater than that of the nonlabile Zn.     

Estimation of bacteriological levels in surface water samples to evaluate their contamination profile

The present work deals with the assessment of bacteriological contamination along with some physico-chemical parameters of water samples from Lahore canal. ANOVA showed that the observed p values of log-transformed viable plate counts, total suspended solids, turbidity, and biological oxygen demand are 0.000, 0.000, 0.000, and 0.000, respectively, which are <0.05, while the p value of total coliforms, total fecal coliforms, and Escherichia coli are 0.728, 0.827, and 0.081, respectively which are >0.05. Significant correlation was observed between log-transformed viable plate counts (CFU), biological oxygen demand, total suspended solids, and turbidity. Further regression analysis revealed that simple line regression model is fit for log-transformed viable plate counts and total suspended solids, log-transformed viable plate counts and turbidity, turbidity and total suspended solids, biological oxygen demand and total suspended solids, biological oxygen demand and log-transformed viable plate counts, and biological oxygen demand and turbidity.     

Physicochemical characteristics of paper industry effluents��a case study of South India Paper Mill (SIPM)

Pulp and paper mills generate varieties of pollutants depending upon type of the pulping process being used. This paper presents the characteristics of wastewater from South India Paper Mill, Karnataka, India which is using recycled waste paper as a raw material. The raw wastewater consists of 80?C90 mg L^???1 suspended solid and 1,010?C1,015 mg L^???1 dissolved solid. However, pH varied from 5.5?C6.8. The biochemical oxygen demand and chemical oxygen demand ranged from 200?C210 and 1,120?C1,160 mg L^???1, respectively. Aerobic treatment of raw effluent attribute to significant reduction in suspended solid (range between 25 to 30 mg L^???1) and total dissolved solid (range between 360 to 390 mg L^???1). However, pH, temperature, and electrical conductivity were found superior after treatment. Copper, cadmium, iron, lead, nickel, and zinc were found in less quantity in raw effluent and were almost completely removed after treatment. The dendrogram of the effluent quality parameters clearly indicate that South India Paper Mill does not meet Minimal National Standard set by central Pollution Control Board to discharge in agricultural field.     

Assessment Of A Natural Wetland For Use In Wastewater Remediation

An environmental study was conducted to assess various aspects of the water and sediment quality of a natural wetland to determine its feasibility for advanced wastewater treatment in Louisiana. Nitrate (NO₃), nitrite (NO₂), ammonia (NH₄), total Kjeldahl nitrogen (TKN), total phosphorus, chloride, total organic carbon, pH, trace metals, fecal coliform, dissolved oxygen (DO), and biochemical oxygen demand (BOD) were monitored. Productivity of a dominant shrub, Iva frutescens, in the wetland was also assessed. Research results indicated that gradients of chloride and salinity concentrations showed a broad mixing of the discharged fresh water into the more saline natural brackish waters. This provided an ideal pattern for nutrient assimilation by the receiving marsh. NH₄ was reduced in the range of 50–100% when all combinations of sources and outflows were considered. For total phosphorus and TKN, reduction ranged from 0–95.1% and 11.2–89.7%, respectively. Some nutrient concentrations in the effluent outlet, NO₃ in particular, were lower than background concentrations found in the reference wetland. Sediment and water showed no significant deficiency or toxicity problems for the major nutrients and metals analyzed. The secondary effluent discharges had little demonstrable negative impact on the wetland during the study period from 1995 to 1996.     

Seasonal and spatial variation of reservoir water quality in the southwest of Ethiopia

This research investigated the spatiotemporal variation of water quality in the Gilgel Gibe reservoir, Ethiopia, using physicochemical water quality parameters. Nonparametric tests and multivariate statistical techniques were used to evaluate data sets measured during dry and rainy seasons. Electrical conductivity (EC), pH, biochemical oxygen demand (BOD₅), total phosphorus (TP), total nitrogen (TN), nitrate (NO₃^?), total dissolved solids (TDSs), and total suspended solids (TSSs) were all significantly different among seasons (Mann-Whitney U test, p?<?0.01). In addition, principal component analysis distinguished dry season samples from wet season samples. The dry season was positively associated with EC, pH, TP, TN, NO₃^?, TDS, and TSS and negatively associated with BOD₅. The wet season was in contrast associated with high values of turbidity, soluble reactive phosphorus (SRP), water temperature, and dissolved oxygen (DO). Within the reservoir, spatial variation was observed for some of the water quality parameters, with significant difference at p?=?<?0.05. Overall, high nutrient concentrations suggest eutrophic conditions, likely due to high nutrient loading from the watershed. Levels of TSS, attributed to inputs from tributaries, have been excessive enough to inhibit light penetration and thus have a considerable impact on the aquatic food web. Our findings indicate that the reservoir is at high risk of eutrophication and siltation, and hence, urgent action should target the planning and implementation of integrated watershed management for this and similar reservoirs in the region.     

Long-term seasonal changes of the Danube River eco-chemical status in the region of Serbia

Seasonal spatial and temporal changes of selected eco-chemical parameters in section of the Danube River flowing through Serbia were analyzed. Data for electrical conductivity (EC), dry and suspended matter, residue on ignition, chemical oxygen demand (COD), biochemical oxygen demand (BOD-5), ultraviolet extinction, dissolved oxygen (DO), oxygen saturation, pH, nitrates, total phosphorus, and nitrogen were collected between 1992 and 2006. The use of monthly medians combined with linear regression and two-sided t test has been proven to be the best approach for resolving trends from natural variability of investigated parameters and for determining trend significance. Patterns of temporal changes between different months were examined. It was also determined that spatial trends of some parameters oscillate in predictable manner, increasing in one part of the year and declining in the other. Regression slope coefficients, an excellent indicator for determining when the water quality is changing the most along the course of the Danube, reach their maximum during summer for temperature (t), electric conductivity, nitrates, and total N, while in the same season suspended matter, COD, BOD-5, DO, and oxygen saturation coefficients reach their minimum. Correlations for used data sets of selected parameters were analyzed for better understanding of their behavior and mutual relations. It was observed that as Danube flows through Serbia, its general eco-chemical status either stagnates or improves, but the rate of river self-purification often depends on the season of the year.     

Interseasonal hydrological characteristics and variabilities in surface water of tropical estuarine ecosystems within Niger Delta, Nigeria

We present a seasonal and baseline survey of selected physicochemical parameters in epipelagic samples from Qua Iboe (QIB) and Cross River (CRV) estuaries in Niger Delta region of Nigeria. The parameters analysed were temperature, pH, salinity, turbidity, total suspended solids (TSS), dissolved oxygen (DO), biochemical oxygen demand (BOD), total organic carbon (TOC), total nitrogen, available phosphorus, Ca^2?+?, Mg^2?+?, Na^?+?, K^?+? (exchangeable cations) and ${\rm SO}_{4}^{2-}$ , Cl^???, ${\rm NH}_{4}^{+}$ and ${\rm NO}_{3}^{-}$ . The results showed that the physicochemical parameters exhibited spatiotemporally explicit variabilities. The mean levels of the parameters were higher during the wet season (June–September) except salinity, DO, Cl^??? and ${\rm NH}_{4}^{+}$ in CRV, whilst QIB recorded higher mean levels for temperature, pH, salinity, BOD, TOC, ${\rm SO}_{4}^{2-}$ , Cl^??? and ${\rm NH}_{4}^{+}$ during the dry season (November–February). Significant seasonal variability was recorded for salinity, DO, turbidity, TSS, ${\rm SO}_{4}^{2-}$ and ${\rm NH}_{4}^{+}$ levels in CRV and for turbidity, DO, BOD, TSS, TOC, available P, Na, Cl^??? and ${\rm NO}_{3}^{-}$ levels in QIB. This study confirmed that the degree of variability of the various physicochemical surface water quality indicators is dependent on the prevalent environmental estuarine factors.     

Potential effects on the marine environment of dredging of the Bonny channel in the Niger Delta

This study is an assessment of the possible effects of the dredging project on the water quality of the surrounding environment. Water quality data for the Bonny offshore river were collected. The parameters assessed were temperature, dissolved oxygen (DO), pH, biochemical oxygen demand (BOD), total dissolved solids (TDS), total suspended solids (TSS), nitrogen as nitrate, and phosphate. The concentrations of TDS, TSS, and nitrate far exceeded the permissible standard. There were significant differences between the dry and rainy season values of BOD5, TDS, TSS, nitrate, and phosphate. Also, the sediment physicochemical analysis indicated the presence of heavy metals such as Pb, Fe, Cd, Zn, Cr, and elements such as Ca, K, and Na. Following an assessment of the potential impact of the project using interaction matrix and checklist questionnaires, results showed that the major physicochemical parameters influenced by dredging are DO, TDS, TSS, heavy metals and calcium, potassium, and sodium. Mitigation measures for eliminating or reducing the negative impacts of dredging are presented.     

Calibration and verification of a dissolved oxygen management model for a highly polluted river with extreme flow variations in Pakistan

A dissolved oxygen (DO) model is calibrated and verified for a highly polluted River Ravi with large flow variations. The model calibration is done under medium flow conditions (431.5 m³/s), whereas the model verification is done using the data collected during low flow conditions (52.6 m³/s). Biokinetic rate coefficients for carbonaceous biochemical oxygen demand (CBOD) and nitrogenous biochemical oxygen demand (NBOD) (i.e, K _cr and K _n ) are determined through the measured CBOD and ammonia river profiles. The calculated values of K _cr and K _n are 0.36 day^?1 and 0.34 day^?1, respectively. The close agreement between the DO model results and the field values shows that the verified model can be used to develop DO management strategies for the River Ravi. The biokinetic coefficients are known to vary with degree of treatment (DOT) and therefore need to be adjusted for a rational water quality management model. The effect of this variation on level of treatment has been evaluated by using the verified model to attain a DO standard of 4 mg/L in the river using the biokinetic rate coefficients as determined during the model calibration and verification process. The required DOT in this case is found to be 96 %, whereas the DOT is 86 % if adjusted biokinetic rate coefficients are used to reflect the effect of wastewater treatment. The cost of wastewater treatment is known to increase exponentially as the removal efficiency increases; therefore, the use of appropriate biokinetic coefficients to manage the water quality in rivers is important.     

结晶紫-聚乙烯醇体系分光光度法测定水中溶解氧

在碘量法测定水中溶解氧的基础上,利用I3-与结晶紫在聚乙烯醇存在下结合成电中性的离子缔合物,以碘酸钾为标准溶液,与过量碘化钾反应生成碘,加入结晶紫后在550 nm处有最大吸收的原理测定水中溶解氧,优化了试验条件,考察了共存离子的干扰。方法在0.002 7 mg/L~0.55 mg/L范围内符合比尔定律,检出限为0.001 1 mg/L,蒸馏水平行测定的RSD≤0.2%,加标回收率为100%~101%,实际水样测定与碘量法和溶解氧测定仪结果一致。