The response of zooplankton assemblages to variations in the water quality of four man-made lakes in semi-arid northeastern Brazil

Abstract Aim The aim of this study was to analyze the water quality of a tropical, semi-arid reservoir after a reflooding. In terms of impact on water quality after a drought event, it is expected that there will be improvements with the reflooding. Less algal biomass, increased water transparency, decreased turbidity and low nutrient concentration. Methods This study was performed in a tropical, semi-arid man-made lake (Dourado Reservoir), during an extended drought period. This study consisted of a comparison of three distinct periods determined by water accumulation. The limnological variables, including water transparency, turbidity, electrical conductivity, pH, total phosphorus, soluble reactive phosphorus, and chlorophyll-a were analyzed. A principal component analysis (PCA) was also performed to verify the patterns of the variables in relation to the sample units in the studied periods. Results After water renewal, there was an expressive reduction in chlorophyll-a. Electrical conductivity, pH, and turbidity variables also reduced after the reflooding, indicating an improvement in water quality. There was no reduction in total phosphorus and soluble reactive phosphorus after the reflooding compared to the previous periods. Conclusions The significant reduction in algal biomass after reflooding in Dourado indicates water quality improvement in terms of eutrophication due to the change of the trophic state from eutrophic to mesotrophic.

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Correction to: Degradation of the macro-drainage water quality of an urban basin in Northeastern Brazil

Environment Development and Sustainability ◽

10.1007/s10668-020-00830-x ◽

2020 ◽

Author(s):

Iana Chaiene de Araujo Vidal ◽

Rui de Oliveira ◽

Mônica de Amorim Coura ◽

Andréa Carla Lima Rodrigues ◽

Francisco das Chagas da Costa Filho ◽

...

Keyword(s):

Water Quality ◽

Drainage Water ◽

Northeastern Brazil

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River water quality improvement by natural and constructed wetland systems in the tropical semi-arid region of Northeastern Brazil

Water Science & Technology ◽

10.2166/wst.2001.0886 ◽

2001 ◽

Vol 44 (11-12) ◽

pp. 599-605 ◽

Cited By ~ 15

Author(s):

B.S.O. de Ceballos ◽

H. Oliveira ◽

C.M.B.S. Meira ◽

A. Konig ◽

A.O. Guimarães ◽

...

Keyword(s):

Water Quality ◽

Constructed Wetland ◽

Arid Region ◽

Northeastern Brazil ◽

Effluent Treatment ◽

Good Efficiency ◽

River Bed ◽

Before And After ◽

Semi Arid Region ◽

Semi Arid

The efficiencies of a natural Typha spp wetland (Wn) formed on a river bed and its effluent treatment in a constructed wetland (Wc, subsurface horizontal flow) were investigated in northeastern Brazil (Paraiba State). The Wc system (12 tanks with stone gravel, 4.13 m2, 0.22 m3, 20 Typha spp rhizomes. m-2 each, with 38, 29, and 19 mm.d-1 hydraulic loadings, and 5, 7, and 10 days HRT) was fed daily with effluent from a Wn. Wn removal presented the highest values after Typha spp were cut during the 5th week. Removal values were (1st and 2nd periods or before and after cutting): 75% and 81% BOD5; 10-53% total phosphorus; 13%-55% ammonia; 89%-91% FC; 90-96% coliphages and bacteriophages. Wc removals increased with time with best results on 10d HRT. Removals were also higher in the 2nd period: 74%-78% BOD5; 58%-82% ammonia; 90% FC; 94-98% FS; and 92%-96% coliphages and bacteriophages. Despite the high remaining values of FC (1.4×104 CFU/100 ml) and FX (4×103 CFU/100 ml), the removals were satisfactory and HRT dependent, suggesting a gradual optimization of the system with time. The Wc exhibited good efficiency for improving water quality from polluted river.

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Impact of filamentous cyanobacteria on the water quality of two tropical reservoirs

RBRH ◽

10.1590/2318-0331.011716072 ◽

2017 ◽

Vol 22 (0) ◽

Author(s):

Mario Ubirajara Gonçalves Barros ◽

Ismael Keslley Carloto Lopes ◽

Stella Maris de Castro Carvalho ◽

José Capelo Neto

Keyword(s):

Water Quality ◽

Inverse Correlation ◽

Fish Farming ◽

Northeastern Brazil ◽

Filamentous Cyanobacteria ◽

Negative Effects ◽

Untreated Wastewater ◽

Flushing Rates ◽

Water Quality Deterioration

ABSTRACT Artificial lakes play an important role in water availability in tropical semi-arid Northeastern Brazil. However, in addition to the negative effects that dams have on the water quality of rivers, other practices such as discharge of untreated wastewater, intensive crop fertilization and fish farming have been contributing to water quality deterioration. Climate change may be another driver of water quality decrease. Increases in precipitation and drought intensities as well as temperature increase may redefine the dynamics of planktonic communities and favour species more adapted to the new environment. Water samples were collected in two reservoirs selected based on the recurrence of positive results for saxitoxins, Acarape do Meio (AM) and Sitios Novos (SN). In general, diversity in SN (1.08) was higher than in the AM (0.60). Phytoplankton dynamics in these reservoirs differ from other reservoirs in the same region of Brazil, in the sense that filamentous cyanobacteria are dominant. Furthermore, lower diversity, concentration and richness of chlorophyceae and bacillariophyceae were found in both reservoirs. Increase in diversity was observed during the intense rainy season of 2011, suggesting a slight improvement of water quality. A close inverse correlation between Cylindrospermopsis sp and other cyanobacteria was found in SN (R2= –0.862) and in AM (R2= –0.997) and the data collected demonstrates that a season with intensive rainfall may lead to lower cyanobacteria concentrations probably due to water dilution and higher flushing rates.

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Socio-economic effect on socially-deprived communities of developing drinking water quality problems in arid and semi-arid area of central Rajasthan

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-364-229-2014 ◽

2014 ◽

Vol 364 ◽

pp. 229-235

Author(s):

I. Husain ◽

J. Husain ◽

M. Arif

Keyword(s):

Water Quality ◽

Drinking Water ◽

Groundwater Quality ◽

Economic Effect ◽

Arid Environment ◽

Quality Data ◽

Toxicological Studies ◽

Ccme Wqi ◽

Semi Arid

Abstract. Rajasthan is well known for its Great Thar desert. Central Rajasthan has an arid to semi-arid environment. The area faces either scarcity of water or poor quality of drinking water. In some areas water is transported 2 km or more, which uses time, energy and money. Rich people have their own sources, which is restricted for use by others. Such conditions are affecting socially-deprived communities, both socially and economically. Groundwater is a major source of drinking water due to the unavailability of surface water. There is a lack of groundwater quality knowledge in the community and the data available is hard to understand by consumers. The CCME Water Quality Index is a tool to simplify the water quality report by rating the water on quality standards. It provides meaningful summaries of overall water quality and trends, which is accessible to non-technical lay people. In the present study the objective is to examine the groundwater quality of six districts (Ajmer, Bhilwara, Pali, Rajasamand, Nagaur and Jodhpur), centrally located in Rajasthan, with arid and semi-arid conditions. CCME WQI is also evaluated to produce quality data in a form to be understood by the community. A total of 4369 groundwater sources in 1680 villages from six districts (76 546 km2) were collected and examined. Results are outlined in the Bureau of Indian Standards (BIS: 10500, 2012) and 2952 sources are unsafe for drinking. According to CCME WQI groundwater of 93 villages is poor, 343 villages are marginal, and 369 villages are fair in quality. Toxicological studies of unsafe drinking water and their remedial measures are also discussed. A tentative correlation between prevailing water-borne diseases and quality parameter has also been shown

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Application of statistical control on water quality in cisterns in the semiarid Pernambucano

Journal of Environmental Analysis and Progress ◽

10.24221/jeap.6.2.2021.2834.128-135 ◽

2021 ◽

Vol 6 (2) ◽

pp. 128-135

Author(s):

Moacyr Cunha Filho ◽

Renisson Neponuceno Araujo Filho ◽

Ana Luiza Xavier Cunha ◽

Isys Pryscilla de Albuquerque Lima ◽

Ana Patricia Siqueira Tavares Falcão ◽

...

Keyword(s):

Water Quality ◽

Control Charts ◽

Fecal Coliforms ◽

Statistical Quality Control ◽

Semiarid Region ◽

Statistical Control ◽

Microbiological Characteristics ◽

Semi Arid Region ◽

Semi Arid

In the Brazilian semi-arid region, it is necessary to use alternatives for the better use of water, since evapotranspiration rates exceed rainfall rates, which may favor salt accumulation in cistern systems. This work aimed to investigate the water quality of cisterns from communities in the semiarid region of Pernambuco state. Thus, the following physicochemical and microbiological characteristics of cistern water were monitored: color, turbidity, total dissolved solids (T.D.S.), salinity through electrical conductivity (EC), pH and total and fecal coliforms. For monitoring, statistical quality control techniques, control charts and process capacity indices were employed. Results were found with high values for microbiological, total and fecal coliforms in most samples. Control charts showed no abnormality in the process. The probable reasons for the contamination of cistern water is the lack of cleaning of the gutters that are part of the stored water catchment system. In the northeastern semi-arid population, people are looking for ways to use natural resources to ensure survival and water quality is seen as a guarantee for quality of life.

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