Iodine and arsenic redox species in oxygen-deficient estuarine waters

1985 ◽  
Vol 36 (3) ◽  
pp. 301 ◽  
Author(s):  
ECV Butler ◽  
JD Smith

The distribution of the redox species of iodine and arsenic in two isolated pools of seawater underlying river water in deep holes in the estuary of the Yarra River is described. In the river water, the dominant species are iodide and As(V). In the saline water of these holes, there are levels of iodine and arsenic greater than are present in the original seawater. The subhalocline waters contained <0.22 ml 1-1 of dissolved oxygen, and the redox poise was intermediate between oxic and anoxic conditions. Most of the iodate originally in the seawater was reduced to iodide, but As111) and As(V) coexisted. Iodine and arsenic appear to have entered the water from the anoxic sediment.

Author(s):  
Sergio Palma ◽  
María Cristina Retamal ◽  
Nelson Silva ◽  
Antonio Canepa

This study characterizes the abundance and spatial distribution of siphonophores between the Trinidad Channel (50°06′S) and the Strait of Magellan (52°45′S) in southern Chile, during October–November 2009. Ten species were identified, of which Agalma elegans, Rosacea plicata and Sphaeronectes fragilis are new records for this region. Dominant species showed similar dominance values e.g. Lensia conoidea (26.3%), Dimophyes arctica (24.6%), Lensia meteori (22.2%) and Muggiaea atlantica (20.7%). Eudoxids of L. conoidea and D. arctica represented 97.3% of all eudoxids collected and they were mainly collected in estuarine waters. The highest densities were found in estuarine waters (high vertical stratification and low temperature, salinity and dissolved oxygen values). On the other hand, the lowest densities were found in coastal areas influenced by permanent influx of Sub-Antarctic waters from the Pacific (greater instability and vertical mixing, higher temperatures, salinity and dissolved oxygen values). Temperature and dissolved oxygen were the most important environmental variables. In general, all the dominant species showed a positive association with temperature and a negative association with dissolved oxygen (with the exception of L. meteori). The vertical distribution showed that M. atlantica was mainly distributed in the first 50 m, in association with estuarine waters, while L. conoidea, L. meteori and D. arctica were mainly found in the deeper layer (50–200 m) and in association with modified Sub-Antarctic waters. The comparison of the results obtained in the springs of 1996 and 2009 showed a significant increase in abundance.


2009 ◽  
Vol 60 (12) ◽  
pp. 1254 ◽  
Author(s):  
T. Venugopal ◽  
L. Giridharan ◽  
M. Jayaprakash

The various factors responsible for the chemical budget and pollution of river water have been evaluated and characterised using various statistical tools. The potential sources of pollution that alter the chemical composition of River Adyar water have been identified and quantified. Thirty-three samples were collected from the River Adyar and basic chemical parameters and heavy metals were interpreted by the systematic application of statistical techniques. The relationships among the various ions were examined and the sources of origin were evaluated using correlation studies. An R-mode factor analysis revealed that the chemistry of the river water largely depends on anthropogenic activities, rock–water interaction and saline water intrusion. A cluster analysis was applied and the major and minor clusters for pre-monsoon and post-monsoon seasons were classified. This classification was found to be in line with the results of the R-mode factor analysis. Seasonal variation in the chemistry and pollution level of the river water was clearly indicated by both cluster and factor analyses. Factor scores, which give vital information on the variation of the factors by station, were successfully applied. The contributing factors and any seasonal effect on the stations were evaluated and interpreted.


2012 ◽  
Vol 9 (2) ◽  
pp. 34 ◽  
Author(s):  
Riche - Hariyati

This research is aimed to study distribution and abundance of meiofauna and the quality of physicochemicalcharacteristics of uppersite of code river and up stream river code Yogyakarta province. Samples weretaken using modified Pysto style corer and were located based on habitat types specific river, which are pool, riffle,rapid, left side and right side of water column. Sample taken four times for each zone. The parameter of for waterquality measured were dissolved oxygen. Water current, alkalinity and pHResult from the analysis showed that the abundance of meiofauna at code river the highest at left side zone.Which was 537.806 individu/m3 with relative abundance was 28,09% result from physico chemical parameter ofdissolved oxygenbetween 5,44 ppm – 6,0 ppm, alkalinity 20 ppm – 25 ppm , pH 7,10 – 7,18.and watercurrenntmeasured between 0,03 m/sec – 0,49 m/sec. The abundance of meiofauna at code river was dominated bygroup of Nematodes horizontal distribution of the fauna was the widest for Nematodes ostracoda, Rhizopoda andinsecta. Physico chemicalquality of code river water was relative good for meiofauna habitat and other waterorganisms


2018 ◽  
Vol 30 ◽  
pp. 01004
Author(s):  
Sylwia Kołaska ◽  
Joanna Jeż – Walkowiak ◽  
Zbysław Dymaczewski

The paper presents characteristics of Debina infiltration intake which provides water for Poznan and neighbouring communes. The evaluation of effectiveness of infiltration process has been done based on the quality parameters of river water and infiltration water. The analysed water quality parameters are as follows: temperature, iron, manganese, DOCKMnO4, TOC, turbidity, colour, dissolved oxygen, free carbon dioxide, conductivity, total hardness, carbonate hardness, pH, heavy metals, detergents and microorganisms. The paper also includes an assessment of the impact of flood conditions on the quality of infiltration water and operation of infiltration intake. In this part of the paper the following parameters were taken into account: iron, manganese, DOCKMnO4, TOC, turbidity, colour, dissolved oxygen, free carbon dioxide, conductivity, total hardness, the total number of microorganisms in 36°C (mesophilic), the total number of microorganisms in 22°C (psychrophilic), coli bacteria, Clostridium perfringens, Escherichia coli, Enterococci. Analysis of the effects of flood on infiltration process leads to the following conclusions: the deterioration of infiltration water quality was due to the deterioration of river water quality, substantial shortening of groundwater passage and partial disappearance of the aeration zone. The observed deterioration of infiltration water quality did not affect the treated water quality, produced at water treatment plant.


2003 ◽  
Vol 69 (6) ◽  
pp. 3526-3531 ◽  
Author(s):  
Courtney S. Pfeffer ◽  
M. Frances Hite ◽  
James D. Oliver

ABSTRACT While several studies on the ecology of Vibrio vulnificus in Gulf Coast environments have been reported, there is little information on the distribution of this pathogen in East Coast waters. Thus, we conducted a multiyear study on the ecology of V. vulnificus in estuarine waters of the eastern United States, employing extensive multiple regression analyses to reveal the major environmental factors controlling the presence of this pathogen, and of Vibrio spp., in these environments. Monthly field samplings were conducted between July 2000 and April 2002 at six different estuarine sites along the eastern coast of North Carolina. At each site, water samples were taken and nine physicochemical parameters were measured. V. vulnificus isolates, along with estuarine bacteria, Vibrio spp., Escherichia coli organisms, and total coliforms, were enumerated in samples from each site by using selective media. During the last 6 months of the study, sediment samples were also analyzed for the presence of vibrios, including V. vulnificus. Isolates were confirmed as V. vulnificus by using hemolysin gene PCR or colony hybridization. V. vulnificus was isolated only when water temperatures were between 15 and 27�C, and its presence correlated with water temperature and dissolved oxygen and vibrio levels. Levels of V. vulnificus in sediments were low, and no evidence for an overwintering in this environment was found. Multiple regression analysis indicated that vibrio levels were controlled primarily by temperature, turbidity, and levels of dissolved oxygen, estuarine bacteria, and coliforms. Water temperature accounted for most of the variability in the concentrations of both V. vulnificus (47%) and Vibrio spp. (48%).


2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Rukumesh Paudyal ◽  
Shichang Kang ◽  
Chhatra Mani Sharma ◽  
Lekhendra Tripathee ◽  
Mika Sillanpää

During post-monsoon 2013, surface water samples were collected form 34 sites from the Bagmati River and its tributaries within the Kathmandu Valley to assess the river water quality. The physical parameters were measured on site and major ions (Na+,NH4+, K+, Mg2+, Ca2+, Cl−,SO42-, andNO3-) and 17 elements in water were analyzed in the laboratory. Conductivity ranged from 21.92 to 846 μS/cm, while turbidity ranged from 2.52 to 223 NTU and dissolved oxygen (DO) ranged from 0.04 to 8.98 mg/L. The ionic and elemental concentrations were higher in the lower section where the population density is high compared to the headwaters. The large input of wastewater and organic load created anoxic condition by consuming dissolved oxygen along the lower belt of the river. The concentration of the elements was found to be in the order of Mn > Zn > Ti > Rb > Cr > Cu > Sc > Ni > V > Li > Co > Mo > Cd > Y > Ga > Be > Nb. The concentration of Mn, Cd, Cr, Co, and Zn was particularly higher in urban and semiurban sections. Enrichment factor (EF) calculations for Cd, Co, and Zn showed their highly enriched values indicating that these elements originated from anthropogenic sources. Preliminary risk assessments were determined by the hazard quotient (HQ) calculations in order to evaluate the health risk of the metals. TheHQingestionvalues of elements were found to be in the order Sb > Mn > Cr > V > Co > Cd > Cu > Zn > Ni > Li > Mo with all averaged HQ values less than 1, indicating no or limited health risk of metals from the river to the local residence. However the values of Sb in some parts of the Bagmati were close to unity indicating its possible threat. Anthropogenic activities like industrial activities, municipal waste water, and road construction besides the river appear to control the chemical constituent of the river water. Overall the river was highly polluted with elevated concentrations of major ions and elements and there is a need for restoration projects.


2020 ◽  
pp. 1-3
Author(s):  
S. Uthirasamy* ◽  
T. Chitra

This study was designed to assess the physico-chemical characteristics of Cauvery river three stations (S1- Domestic sewage release place, S2- Pooja waste release place and S3- People dress washing place. Erode. The parameters were analysed such as Temperature, pH, Colour, Odour, Turbidity, DO2, BOD, COD, Salinity, Total alkalinity and Total hardness. The pH ranged from (8.2 to 8.7), Dissolved oxygen (4.987 to 6.253mg/lit), BOD (13.768 to 17.564mg/lit), as recorded in S1 Place. COD (34.7 to 36.7mg/lit), Calcium (89 to 105mg/lit), Salinity (7.12 to 12.6mg/lit), as observed in S2 place. Total Alkalinity (164 to 198mg/lit), Nitrate (0.32 to 0.45mg/lit) and Phosphate (0.34 to 0.40mg/lit) as analyzed in S3 Place. The nding of the study revealed that the river water is polluted not advisable for human usage without any treatment. This study concluded that the seriousness and responsibility of public to conserve our water resources for healthy living.


Sign in / Sign up

Export Citation Format

Share Document