A study aimed at evaluating the physicochemical and bacteriological quality of surface water was therefore carried out in a few watercourses in the municipality of Mbankomo, located in the Center Region (Cameroon). Th...A study aimed at evaluating the physicochemical and bacteriological quality of surface water was therefore carried out in a few watercourses in the municipality of Mbankomo, located in the Center Region (Cameroon). The physico-chemical parameters were measured according to the standard method. The organic pollution index (OPI) was determined from the contents of nitrates, phosphates, and ammoniacal nitrogen to characterize the level of organic pollution of the water. The microorganisms sought were total flora, indicators of faecal contamination like total coliforms, faecal coliforms, feacal streptococci and Escherichia coli, as well as the species Clostridium perfringens. The organic pollution index indicates a high-level organic pollution level during the small rainy season and high to moderate during the small dry season. High concentrations of the total and fecal coliforms, streptococci fecal, Escherichia coli and Clostridium perfringens respectively of 1712 × 10<sup>5</sup> CFU/100mL;82 × 10<sup>5</sup> CFU/100mL;10 × 10<sup>5</sup> CFU/100mL;27 × 10<sup>5</sup> and 40 × 10<sup>3</sup> CFU/100mL, all higher than WHO standards, indicate that the waterways of Mbankomo are subject to feacal pollution and harbor pathogenic microflora. The cell densities of main bacteria were significantly correlated with main abiotic parameters, such as Escherichia coli, which was significantly correlated with the pH of the water (r = 0.35;p < 0.05). The variation of organic pollution index category means correspond to a high level of organic pollution during the small rainy season and a high to moderate level during the small dry season. The deterioration of the quality of these waters is favored by their proximity to sources of pollution (toilets, plantation), the runoff of the waters contaminated, the use of detergents and wrong maintenance. These waters without any treatment are not recommendable for human consumption according to standards of the World Health Organization.展开更多
Trace pollutants in the surface water of the Arctic region have been analyzed by the capillary gas chro-matography with the micro-electron capture detector (GC- mECD), the gas chromatography-mass spectrometry (GC- MS)...Trace pollutants in the surface water of the Arctic region have been analyzed by the capillary gas chro-matography with the micro-electron capture detector (GC- mECD), the gas chromatography-mass spectrometry (GC- MS) and the inductively coupled plasmas-mass spectrometry (ICP-MS). Compared with previously reported studies, concentrations of OCPs in these regions are much lower than those in the last decades. The ratio of a-/g-HCH indicates the different pesticide composition between these two regions and is the potential marker for the source of the OCPs. Many other OCPs with different residue patterns have also been found for the first time in the two regions. No heavy metal contaminant was found in the investigation regions.展开更多
文摘A study aimed at evaluating the physicochemical and bacteriological quality of surface water was therefore carried out in a few watercourses in the municipality of Mbankomo, located in the Center Region (Cameroon). The physico-chemical parameters were measured according to the standard method. The organic pollution index (OPI) was determined from the contents of nitrates, phosphates, and ammoniacal nitrogen to characterize the level of organic pollution of the water. The microorganisms sought were total flora, indicators of faecal contamination like total coliforms, faecal coliforms, feacal streptococci and Escherichia coli, as well as the species Clostridium perfringens. The organic pollution index indicates a high-level organic pollution level during the small rainy season and high to moderate during the small dry season. High concentrations of the total and fecal coliforms, streptococci fecal, Escherichia coli and Clostridium perfringens respectively of 1712 × 10<sup>5</sup> CFU/100mL;82 × 10<sup>5</sup> CFU/100mL;10 × 10<sup>5</sup> CFU/100mL;27 × 10<sup>5</sup> and 40 × 10<sup>3</sup> CFU/100mL, all higher than WHO standards, indicate that the waterways of Mbankomo are subject to feacal pollution and harbor pathogenic microflora. The cell densities of main bacteria were significantly correlated with main abiotic parameters, such as Escherichia coli, which was significantly correlated with the pH of the water (r = 0.35;p < 0.05). The variation of organic pollution index category means correspond to a high level of organic pollution during the small rainy season and a high to moderate level during the small dry season. The deterioration of the quality of these waters is favored by their proximity to sources of pollution (toilets, plantation), the runoff of the waters contaminated, the use of detergents and wrong maintenance. These waters without any treatment are not recommendable for human consumption according to standards of the World Health Organization.
基金This work was supported by the Chinese First Arctic Research Expedition,Office of Polar Expedition,State Oceanic Administration of China and Innovation Project of Chinese Academy of Science (Grant No. KZCX2-414).
文摘Trace pollutants in the surface water of the Arctic region have been analyzed by the capillary gas chro-matography with the micro-electron capture detector (GC- mECD), the gas chromatography-mass spectrometry (GC- MS) and the inductively coupled plasmas-mass spectrometry (ICP-MS). Compared with previously reported studies, concentrations of OCPs in these regions are much lower than those in the last decades. The ratio of a-/g-HCH indicates the different pesticide composition between these two regions and is the potential marker for the source of the OCPs. Many other OCPs with different residue patterns have also been found for the first time in the two regions. No heavy metal contaminant was found in the investigation regions.
