The quality of surface waters is often altered by the presence of bacteria of faecal origin, as a result of untimely discharge of solid and liquid waste from households. The Sonfonia Lake located in the commune of Rat...The quality of surface waters is often altered by the presence of bacteria of faecal origin, as a result of untimely discharge of solid and liquid waste from households. The Sonfonia Lake located in the commune of Ratoma is under the influence of various forms of pollution resulting for the most part from anthropic activities. Field visits, interviews with resource persons and bacteriological analysis were carried out to assess the level of this pollution. Two water sampling campaigns were carried out during the low-water period and two others during the flood period of 2021. The comparison of the levels of faecal contamination bacteria in the present study with a previous one carried out in 2018 on the waters of the same lake, indicates an increase in the level of faecal coliforms and faecal streptococci that exceed the indicator values recommended by the WHO. These results show that Lake Sonfonia is polluted. This could be related to the increase in anthropogenic and demographic activities during the last four years. On the other hand, the analysis of the results showed the absence of pathogenic germs such as salmonella. The Mann-Whitney U statistical test was used to compare the value of the means of each of the variables observed during the two seasons.展开更多
As part of the determination of the possible impact of human activities on surface waters, case of Lake Sonfonia, six sampling sites were selected according to their solicitation by the population and their exposure t...As part of the determination of the possible impact of human activities on surface waters, case of Lake Sonfonia, six sampling sites were selected according to their solicitation by the population and their exposure to probable sources of pollution. The objective of this work is to monitor the physico-chemical quality of the waters of Lake Sonfonia during the low water level (March) and during the flood period (August) of the year 2021. Two sampling campaigns of water were carried out in dry weather and two others in cold weather. Parameters such as temperature, pH, EC (Electrical Conductivity), dissolved oxygen, TDS (Total Dissolved Solids) were measured in situ. Suspended matter, phosphate, nitrate, nitrite, sulphates, total iron, COD (Chemical Oxygen Demand) were measured in the laboratory by the colorimetric method. Stata 15 software was applied for the statistical analysis of the data and the correlation test between the parameters gave highly significant correlations. It has been noted that the situation is not very good and that this pollution comes mainly from human activities.展开更多
文摘The quality of surface waters is often altered by the presence of bacteria of faecal origin, as a result of untimely discharge of solid and liquid waste from households. The Sonfonia Lake located in the commune of Ratoma is under the influence of various forms of pollution resulting for the most part from anthropic activities. Field visits, interviews with resource persons and bacteriological analysis were carried out to assess the level of this pollution. Two water sampling campaigns were carried out during the low-water period and two others during the flood period of 2021. The comparison of the levels of faecal contamination bacteria in the present study with a previous one carried out in 2018 on the waters of the same lake, indicates an increase in the level of faecal coliforms and faecal streptococci that exceed the indicator values recommended by the WHO. These results show that Lake Sonfonia is polluted. This could be related to the increase in anthropogenic and demographic activities during the last four years. On the other hand, the analysis of the results showed the absence of pathogenic germs such as salmonella. The Mann-Whitney U statistical test was used to compare the value of the means of each of the variables observed during the two seasons.
文摘As part of the determination of the possible impact of human activities on surface waters, case of Lake Sonfonia, six sampling sites were selected according to their solicitation by the population and their exposure to probable sources of pollution. The objective of this work is to monitor the physico-chemical quality of the waters of Lake Sonfonia during the low water level (March) and during the flood period (August) of the year 2021. Two sampling campaigns of water were carried out in dry weather and two others in cold weather. Parameters such as temperature, pH, EC (Electrical Conductivity), dissolved oxygen, TDS (Total Dissolved Solids) were measured in situ. Suspended matter, phosphate, nitrate, nitrite, sulphates, total iron, COD (Chemical Oxygen Demand) were measured in the laboratory by the colorimetric method. Stata 15 software was applied for the statistical analysis of the data and the correlation test between the parameters gave highly significant correlations. It has been noted that the situation is not very good and that this pollution comes mainly from human activities.
