Water Quality From Gualaxo Do Norte And Carmo Rivers (Minas Gerais, Brazil) After The Fundão Dam Failure

Author(s):  
Leonardo Brandão Nogueira ◽  
Sabriny Melo Sousa ◽  
Camila Gonçalves Lobo Santos ◽  
Gustavo Simões Araújo ◽  
Laser Oliveira ◽  
...  

Mining waste is rich in trace elements, which present a high toxic potential and may represent a risk for aquatic ecosystems. The Fundão dam failure, considered the largest environmental disaster in the world, affected 663.2 km of watercourses, including Carmo and Gualaxo do Norte Rivers. The ore tail also affected the riverside communities, destroying villages, killing people and affecting the subsistence farming. To evaluate the influence of the mine tailing wave on the water quality of the Carmo and Gualaxo do Norte Rivers water samples were collected at nine points located in Barra Longa during the rainy season. Physicochemical parameters (conductivity, resistivity, EH, total dissolved solids, pH and temperature) and major, minor and trace elements concentrations (Ba, Co, Cr, Cu, Ni, Sc, Sr, V, Zn, As, Pb, Al, Fe, Mn, Ca, K, Mg and P) were evaluated and compared with previous studies and conformity limits established by a national resolution (CONAMA Resolution N°357/2005). Only conductivity, Fe and Mn presented non-conformity values according to CONAMA Resolution N°357/2005. These results may be related not only to the dam burst but also to the rainy season and non-detectable pollution sources. Furthermore, the decreased levels in the toxic elements in the rivers over time, may be related to its association with sediments in addition to their flux to the Atlantic Ocean. Thus, after nearly six years, the environmental and social impacts are still alive and the minerals dragged to the riverbed could bring cumulative effects for the entire environment what means an uncertain future to the Rio Doce Basin and adjacent coastal zone.

2021 ◽  
Vol 27 (1) ◽  
pp. 6-14
Author(s):  
V. Zaslonovsky ◽  
◽  
N. Sharapov ◽  
M. Bosov ◽  
◽  
...  

The paper is devoted to the development of proposals concerning the improvement of surface water bodies and the appointment of target indicators of the natural waters’ quality. The paper considers a variety of problems of preserving, restoring and improving the quality of natural surface waters: from regional features of the formation of natural water composition, to differences in the requirements for the quality of water consumed. The object of the study is the qualitative indicators of the waters of natural water bodies, and the subject of the study is the methodological approaches to the normalization of these indicators. The purpose of the work is to identify the main shortcomings in the domestic system of rationing the quality of natural waters, and to form appropriate proposals. For this purpose, the following tasks were set and solved: to review the methodological approaches to assessing and rationing the quality of natural waters used in some foreign countries and in the Russian Federation, to identify the main causes and shortcomings; to make proposals for improving the current system of water quality rationing. The result of this work is the conclusions about the lack of impact of the strategy operating in Russia in the development of schemes of complex use and protection of water objects, standards of permissible impact on water bodies, the appointment of permissible discharge limits in terms of maintaining and improving the water quality of natural water bodies. The reasons that led to this are indicated. The necessity of taking into account, in addition to the physical and chemical composition, also hydrobiological parameters is shown. It is concluded that instead of fisheries management standards, environmental standards should serve as the basis for target indicators of water quality of natural water bodies, which determine the well-being of humans and the stable functioning of aquatic ecosystems, taking into account regional factors. Proposals were made to adjust the methodological approaches to the implementation of this strategy. According to the authors, these proposals will speed up the solution of the main objectives of the strategy – the ecological improvement of water bodies, the preservation of unique aquatic ecosystems and the environmentally safe development of territories that previously experienced relatively small anthropogenic impacts (Eastern Siberia and the Far East)


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Elarina N. Dkhar ◽  
Paul S. Dkhar ◽  
Jasha Momo H. Anal

Determination of the certain major and trace elements was carried out in drinking water supply scheme in three districts of Meghalaya. This work aims to identify trends resulting in the deterioration of drinking water which is also a potential source of environmental contaminants. About 50 samples, each from one district, were collected both from the source and various tanks and tap. The elements determined are Li, Na, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Rb, Ag, Au, Pb, Cd, Se, Ca, K, and Mg. The pH is slightly lower than neutral pH of 7 while the turbidity is very high even after treatment. The concentrations of Ca and Mg are found to be deficient. The elements Cr, Fe, Co, Ni, Zn, Mo, and Pb decrease after treatment while Mn, Cu, and Cd increase slightly after treatment. Se concentration is found to be much higher than expected. The results were compared with the standard recommendation values for the quality of drinking water. This study provides a general indication of where water-quality constituent concentrations met or exceeded water-quality standards and the data presented in this report will be useful from public health point of view.


2019 ◽  
Vol 19 (1) ◽  
pp. 57-66
Author(s):  
Le Thi Vinh ◽  
Nguyen Hong Thu ◽  
Pham Huu Tam ◽  
Le Trong Dung

The results of three surveys in the O Loan lagoon in the dry season (April 2013) and the rainy season (December 2012 and December 2014) showed that in the rainy season the average concentrations of nutrients in waters (ammonium: 76.8 μgN/l, nitrite: 13.9 μgN/l, nitrate: 55 μgN/l and silicate: 4021 μgSi/l) tended to be higher than those in the dry season (ammonium: 6.0 μgN/l, nitrite: 2.6 μgN/L, nitrate: 35 μgN/l and silicate: 1973 μgSi/l) while phosphate concentraiton did not differ between the two seasons with an average concentration of 66.8 μgP/l in rainy season and 60 μgP/L in dry season. By space, the concentrations of nutrients except nitrate in the lagoon, especially in the southern part, were usually higher than those in the canal connected to the sea. At O Loan lagoon waters, only ammonium (mainly in the southern part of the lagoon) and nitrate (mainly in the canal and southern part of the lagoon) concentrations were higher than the criteria values in the rainy season (December 2014) with pollution coefficient of about 1.2. However, the water quality of O Loan lagoon regarding nutrients always still needs to be monitored because from 1992 to the surveyed time, the concentrations of nutrients containing nitrogen and phosphate had the increasing trend in both seasons.


2015 ◽  
Vol 75 (1) ◽  
pp. 125-134 ◽  
Author(s):  
JL. Rodrigues-Filho ◽  
RM. Degani ◽  
FS. Soares ◽  
NA. Periotto ◽  
FP. Blanco ◽  
...  

The amendments to the Forest Law proposed by the Brazilian government that allow partial substitution of forested areas by agricultural activities raised deep concern about the integrity of aquatic ecosystems. To assess the impacts of this alteration in land uses on the watershed, diffuse loads of total nitrogen (Nt) and total phosphorus (Pt) were estimated in Lobo Stream watershed, southeastern Brazil, based on export coefficients of the Model of Correlation between Land Use and Water Quality (MQUAL). Three scenarios were generated: scenario 1 (present scenario), with 30-meter-wide permanent preservation areas along the shore of water bodies and 50-meter-radius in springs; scenario 2, conservative, with 100-meter-wide permanent preservation areas along water bodies; and scenario 3, with the substitution of 20% of natural forest by agricultural activities. Results indicate that a suppression of 20% of forest cover would cause an increase in nutrient loads as well as in the trophic state of aquatic ecosystems of the watershed. This could result in losses of ecosystem services and compromise the quality of water and its supply for the basin. This study underlines the importance of forest cover for the maintenance of water quality in Lobo Stream watershed.


Geosciences ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 464
Author(s):  
Tatiana Kondrateva ◽  
Tatiana Nikonenkova ◽  
Nadezhda Stepanova

We assess the quality of surface water in water bodies located in the Middle Volga region (Russian Federation). The water quality is assessed using 19 chemical compounds and cilioplankton indicators, such as the total number of species, the abundance of each species, and, based on both of them, the saprobity index and the Shannon–Weaver diversity index (H). We classify the water quality from polluted to extremely dirty by using abiotic indicators, and from conditionally clean to dirty by means of biotic indicators. Using the logistic regression method, we are able to predict the water quality (clean or dirty) in correspondence with the species diversity index (H) and to clarify how the quality of the water is related to its physicochemical properties. The seven most significant chemical predictors of both natural origin (mineralization, hydro carbonates, and chlorides) and natural-anthropogenic origin (organic substances (according to BOD5), nitrates, total petroleum hydrocarbons, iron), identified during the stepwise selection procedure, have a substantial influence on the outcome of the model. Qualitative and quantitative indicators of development of ciliates, as well as indices calculated on their basis, allow assessing with a very high level of accuracy the water quality and the condition of aquatic ecosystems in general. The Shannon index calculated for the number of ciliates can be successfully used for ranking water bodies as “clean/dirty”.


Author(s):  
Hazimah Haspi Harun ◽  
Mohamad Roslan Mohamad Kasim ◽  
Siti Nurhidayu ◽  
Zulfa Hanan Ash’aari ◽  
Faradiella Mohd Kusin ◽  
...  

The aim of this study was to propose a groundwater quality index (GWQI) that presents water quality data as a single number and represents the water quality level. The development of the GWQI in agricultural areas is vital as the groundwater considered as an alternative water source for domestic purposes. The insufficiency of the groundwater quality standard in Malaysia revealed the importance of the GWQI development in determining the quality of groundwater. Groundwater samples were collected from thirteen groundwater wells in the Northern Kuala Langat and the Southern Kuala Langat regions from February 2018 to January 2019. Thirty-four parameters that embodied physicochemical characteristics, aggregate indicator, major ions, and trace elements were considered in the development of the GWQI. Multivariate analysis has been used to finalize the important parameters by using principal component analysis (PCA). Notably, seven parameters—electrical conductivity, chemical oxygen demand (COD), magnesium, calcium, potassium, sodium, and chloride were chosen to evaluate the quality of groundwater. The GWQI was then verified by comparing the groundwater quality in Kota Bharu, Kelantan. A sensitivity analysis was performed on this index to verify its reliability. The sensitivity GWQI has been analyzed and showed high sensitivity to any changes of the pollutant parameters. The development of GWQI should be beneficial to the public, practitioners, and industries. From another angle, this index can help to detect any form of pollution which ultimately could be minimized by controlling the sources of pollutants.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Agnieszka Napiórkowska-Krzebietke ◽  
Andrzej Robert Skrzypczak

AbstractEach newly-created pond which is supplied with mine water gives the opportunity to study a unique ecosystem in context of possible conditions for biotic live. Therefore, this research aimed to assess a phytoplankton-based ecological potential against the trophic conditions and the risk of contamination with trace elements, and demonstrate the possibility to stabilize at least good water quality of a clarification pond. The gradual decrease in turbidity-related variables (including suspended solids and iron) and nutrients, on the one hand, and an increase in phytoplankton-related indicators, on the other hand, were the most evident. Besides, relative stability in trace elements (the best water quality class), trophic level (slightly eutrophic level) and ecological potential (maximum potential), and relative instability in sulfates and calcium were also recorded. The final stabilization of water habitat resulted in abundant growth of charophyte Nitella mucronata. This all suggested a new ecological opportunity for settlement of a rare species and important for biodiversity enhancement. Furthermore, the study revealed that a clarification pond did not pose any toxic risk from the elevated content of trace elements or the growth of toxic or potentially toxic cyanobacteria which is essential for proper functioning and management of water ecosystems.


Author(s):  
Addy Jose Vershima ◽  
Kabough Jonathan Terkimbi ◽  
Azua Terese ◽  
Aliyu Ibrahim

Water samples of six sampling sites (two downstream, two abattoir sites and two upstream sites) were analyzed using standard methods to determined and assessed heavy metal content of abattoir effluent on surface water quality of River Katsina-Ala, Benue State, Nigeria for rainy and dry seasons. Rainy season heavy metals results were; Cr6+ (0.032+0.06mg/l); Mn2+ (0.16+0.034mg/l); Cu2+ (0.86 +0.46mg/l); Pb2+(0.006+0.002mg/;Cd2+(0.0023+0.004mg/l) and the dry season results were: Cr6+(0.028+0.007mg/l); Mn2+(0.07+0.05mg/l); Cu2+(0.85+0.16mg/l); Pb2+(0.0030+0.014mg/l); Cd2+(0.0021+0.012mg/). Most heavy metals for both seasons were within the maximum permissible limit set by Federal Ministry of Environment, Nigeria (1991). The mean concentrations of Zn2+(1.70+0.29 mg/l) for rainy season and Zn2+(1.33+0.23mg/l) dry season were above the control and standard safe limits of < 1mg/l FMEnv (1991) for surface water quality. There was no significance difference (p<0.05) between the means from upstream and downstream sites for both seasons; though significance difference (p<0.05) existed at the abattoir sites. River Katsina –ala is slightly polluted. Heavy metal content from effluents from abattoir contributed to upset the physicochemical balance of the river. Bioaccumulation and bio-magnification of heavy metals may occur from prolong usage of the river water for drinking. It is suggested that the abattoir effluent be treated before discharge into the river to reduce environmental and health hazards.


2021 ◽  
pp. 55-62
Author(s):  
René Rodríguez-Grimón ◽  
Juan Valenzuela-Cobos ◽  
Juan Erazo-Delgado ◽  
Narvaez Teran ◽  
María Garcés-Moncayo ◽  
...  

The water quality of the San Camilo and Mojahuevo estuaries was monitored in the months of April (rainy season) and June (dry season) of 2016. The water of the Mojahuevo estury presented in both seasons the lowest values of turbidity between 17.20 and 33.70 UNT, biochemical oxygen demand being in a range between 14.00 and 19.00 mg/L, zinc content (0.02-0.05 mg/L) and copper content (0.07 mg/L), ammonia content (0.21-0.35 mg/L), fats and oils (0.23-0.29 mg/L), phosphates (0.39-2.34 mg/L) and nitrates (0.84-2.29 mg/L), while the water of the two estuaries San Camilo and Mojahuevo (rainy season) showed similar phenolic content (0.019 mg/L). The results showed that the Mojahuevo estuary presented the high quality of water recommended for being used in productive process like aquaculture due to the low presence of pollutants.


Sign in / Sign up

Export Citation Format

Share Document