This study investigated the major ion composition and sources in wet and dry deposition samples collected over 15 months (December 2017 to February 2019) at four stations representing four different land use/cover typ...This study investigated the major ion composition and sources in wet and dry deposition samples collected over 15 months (December 2017 to February 2019) at four stations representing four different land use/cover types on the western side of Lake Kivu basin in D.R. Congo. The samples were collected every 13 days for dry deposition and two to three times per month for wet deposition. Samples were analyzed for major ionic components (Cl<sup>-, NO<sub>-</sub>3</sup>, SO<sub>2-</sub>4</sup>, Na<sup>+</sup>, K<sup>+</sup>, NH<sub>+</sub>4</sup>, Ca<sup>2+</sup>, CO<sub>2-</sub>3</sup>, HCO<sub>-</sub>3</sup> and Mg<sup>2+</sup>). Electrical conductivity and pH were analyzed immediately in the field while major ion measurements were in the laboratory. Results showed the pH of both the dry and the wet depositions were higher than what would have been expected based on equilibration with atmospheric CO<sub>2</sub> (pH > 5.6) at all four sites, with conductivity less than 50 μS/cm. The neutralization process in dry and wet atmospheric deposition is due to Ca<sup>2+</sup>, NH<sub>+</sub>4</sup>, HCO<sub>-</sub>3</sup> and CO<sub>2-</sub>3</sup>. The anion: cation ratio in dry deposition was close to 1 for Iko and Bukavu, and it was greater than 1.0 (1.1 - 1.2) for Lwiro and Goma in wet deposition. The dominant anions in wet deposition were SO<sub>2-</sub>4</sup> and NO<sub>-</sub>3</sup>, found around the rural area near cement factory and the urban area near active volcanoes, respectively. The most abundant cation was Na+ followed by K<sup>+</sup>. The enrichment factors and correlation analysis suggest that the main sources of Ca<sup>2+</sup>, Na<sup>+</sup> and Mg<sup>2+</sup> were disintegration of soil processes, aeolian suspension of soil and volcanic ash, biomass burning and the cement/lime factory around the Lake Kivu basin.展开更多
A systematic study has been carried out to assess the water quality in and around Lake Edward basin in D.R. Congo Side. Fifty four water samples were collected and analyzed for physicochemical parameters, including: t...A systematic study has been carried out to assess the water quality in and around Lake Edward basin in D.R. Congo Side. Fifty four water samples were collected and analyzed for physicochemical parameters, including: temperature, discharge, pH, electrical conductivity, transparency, dissolved oxygen, COD, BOD, Carbonate, Bicarbonate, alkalinity, total hardness, turbidity, calcium hardness, calcium, magnesium hardness, magnesium, total nitrogen, ammonium, nitrate, total phosphorus, soluble reactive phosphorus, chloride, sulphate and total suspended solids. For bacteriological parameters: fecal bacteria, enterococcus bacteria, vibrio and salmonella shigella bacteria were considered. For macroinvertebrates assemblages all taxa using standards methods for each parameter. A comparison of data from dry (June to August) and wet (September to May) season was done in and around Lake Eduard watershed. The analytical data of various physicochemical parameters indicates that water characteristics in the watershed were in the limit of WHO standards for drinking water and aquatic life. Bacteriological water quality of some ecosystems in the watershed revealed the infestation of water with bacteria which make the water unusable for drinking by the surrounding population near and within Lake Eduard watershed. Longtime period sampling in the watershed is needed to understand the variation and composition of water quality and aquatic macroinvertebrate environment of the watershed.展开更多
Atmospheric deposition of nutrients, particularly nitrogen and phosphorus has the capacity to significantly affect the productivity and biogeochemistry of aquatic ecosystems. The objective of this study was to assess ...Atmospheric deposition of nutrients, particularly nitrogen and phosphorus has the capacity to significantly affect the productivity and biogeochemistry of aquatic ecosystems. The objective of this study was to assess the impact of land use/cover types on the atmospheric deposition of nutrients around Lake Kivu. Dry and wet atmospheric deposition samples were collected from four different land use/cover types (forest, wetland, agricultural and urbanized area) at four stations (Goma, Lwiro, Bukavu and Iko) around the Lake Kivu basin. The highest annual loading of dry total phosphorus (TP) was recorded at a station located in an urban area at Goma (4.4 ± 3.9 μmol/m<sup>2</sup>/yr) and the highest dry deposition of total nitrogen (TN) was recorded at Iko (84.5 ± 41.2 μmol/m<sup>2</sup>/yr). High wet TP and TN were at Bukavu (0.7 ± 1.1 μmol/m<sup>2</sup>/yr) and Iko (21.7 ± 34.7 μmol/m<sup>2</sup>/yr) respectively. High dry TP loads were recorded in the forest area of Goma and the highest dry TN at Lwiro. High wet TP loads were record in agriculture at Goma and high values of wet TN in agriculture at Iko. Phosphorus and nitrogen deposition rates around Lake Kivu were similar to those reported for other African lakes. The highest rate of TP was recorded mainly in the forest area for dry deposition while high TN was recorded in all types of land use/cover in the basin. This study found out that forest traps high concentration of nutrient than other land uses/covers.展开更多
Monitoring of environmental parameters is one of the highest priorities in the evaluation of environmental status of water resources and in environmental protection policy. The main objectives are to understand and ev...Monitoring of environmental parameters is one of the highest priorities in the evaluation of environmental status of water resources and in environmental protection policy. The main objectives are to understand and evaluate the water quantity and quality in order to provide water of appropriate quality to various water users. The water quantity was assessed by the measurement of runoff or discharge at specific river cross sections using floating method for surface water and bucket and stopwatch method for springs and boreholes. The quality of river water and spring was identified in terms of its physical, chemical, and biological parameters. The analyzed data were compared with standard values recommended by WHO. Macroinvertebrates were collected in the rivers using a plankton nets and 10 minutes of sampling. Identification was made at the laboratory of Malacology. Results revealed that the quality of water obtained from sampling points is generally good to use for different domestic purposes except the Idanta River and Rwembwe borehole, which need an appropriate treatment before use. All sampling points are located far from houses and latrines, which can contribute to fecal contamination. On the different sampling points, bathing and washing clothes were observed and could constitute the source of pollution of drinking water. In Idanta and Kamira Rivers animals used water for drinking while also people use this water for domestic and drinking. In the two sampling points high values of Escherichia coli were found. No pollutant-taxa tolerant were found in the two monitored rivers for macroinvertebrates. Since water quality and quantity remain a major challenge in rural areas, the government should provide safe water to the population around Mikeno sector after treatment using suitable techniques.展开更多
文摘This study investigated the major ion composition and sources in wet and dry deposition samples collected over 15 months (December 2017 to February 2019) at four stations representing four different land use/cover types on the western side of Lake Kivu basin in D.R. Congo. The samples were collected every 13 days for dry deposition and two to three times per month for wet deposition. Samples were analyzed for major ionic components (Cl<sup>-, NO<sub>-</sub>3</sup>, SO<sub>2-</sub>4</sup>, Na<sup>+</sup>, K<sup>+</sup>, NH<sub>+</sub>4</sup>, Ca<sup>2+</sup>, CO<sub>2-</sub>3</sup>, HCO<sub>-</sub>3</sup> and Mg<sup>2+</sup>). Electrical conductivity and pH were analyzed immediately in the field while major ion measurements were in the laboratory. Results showed the pH of both the dry and the wet depositions were higher than what would have been expected based on equilibration with atmospheric CO<sub>2</sub> (pH > 5.6) at all four sites, with conductivity less than 50 μS/cm. The neutralization process in dry and wet atmospheric deposition is due to Ca<sup>2+</sup>, NH<sub>+</sub>4</sup>, HCO<sub>-</sub>3</sup> and CO<sub>2-</sub>3</sup>. The anion: cation ratio in dry deposition was close to 1 for Iko and Bukavu, and it was greater than 1.0 (1.1 - 1.2) for Lwiro and Goma in wet deposition. The dominant anions in wet deposition were SO<sub>2-</sub>4</sup> and NO<sub>-</sub>3</sup>, found around the rural area near cement factory and the urban area near active volcanoes, respectively. The most abundant cation was Na+ followed by K<sup>+</sup>. The enrichment factors and correlation analysis suggest that the main sources of Ca<sup>2+</sup>, Na<sup>+</sup> and Mg<sup>2+</sup> were disintegration of soil processes, aeolian suspension of soil and volcanic ash, biomass burning and the cement/lime factory around the Lake Kivu basin.
文摘A systematic study has been carried out to assess the water quality in and around Lake Edward basin in D.R. Congo Side. Fifty four water samples were collected and analyzed for physicochemical parameters, including: temperature, discharge, pH, electrical conductivity, transparency, dissolved oxygen, COD, BOD, Carbonate, Bicarbonate, alkalinity, total hardness, turbidity, calcium hardness, calcium, magnesium hardness, magnesium, total nitrogen, ammonium, nitrate, total phosphorus, soluble reactive phosphorus, chloride, sulphate and total suspended solids. For bacteriological parameters: fecal bacteria, enterococcus bacteria, vibrio and salmonella shigella bacteria were considered. For macroinvertebrates assemblages all taxa using standards methods for each parameter. A comparison of data from dry (June to August) and wet (September to May) season was done in and around Lake Eduard watershed. The analytical data of various physicochemical parameters indicates that water characteristics in the watershed were in the limit of WHO standards for drinking water and aquatic life. Bacteriological water quality of some ecosystems in the watershed revealed the infestation of water with bacteria which make the water unusable for drinking by the surrounding population near and within Lake Eduard watershed. Longtime period sampling in the watershed is needed to understand the variation and composition of water quality and aquatic macroinvertebrate environment of the watershed.
文摘Atmospheric deposition of nutrients, particularly nitrogen and phosphorus has the capacity to significantly affect the productivity and biogeochemistry of aquatic ecosystems. The objective of this study was to assess the impact of land use/cover types on the atmospheric deposition of nutrients around Lake Kivu. Dry and wet atmospheric deposition samples were collected from four different land use/cover types (forest, wetland, agricultural and urbanized area) at four stations (Goma, Lwiro, Bukavu and Iko) around the Lake Kivu basin. The highest annual loading of dry total phosphorus (TP) was recorded at a station located in an urban area at Goma (4.4 ± 3.9 μmol/m<sup>2</sup>/yr) and the highest dry deposition of total nitrogen (TN) was recorded at Iko (84.5 ± 41.2 μmol/m<sup>2</sup>/yr). High wet TP and TN were at Bukavu (0.7 ± 1.1 μmol/m<sup>2</sup>/yr) and Iko (21.7 ± 34.7 μmol/m<sup>2</sup>/yr) respectively. High dry TP loads were recorded in the forest area of Goma and the highest dry TN at Lwiro. High wet TP loads were record in agriculture at Goma and high values of wet TN in agriculture at Iko. Phosphorus and nitrogen deposition rates around Lake Kivu were similar to those reported for other African lakes. The highest rate of TP was recorded mainly in the forest area for dry deposition while high TN was recorded in all types of land use/cover in the basin. This study found out that forest traps high concentration of nutrient than other land uses/covers.
文摘Monitoring of environmental parameters is one of the highest priorities in the evaluation of environmental status of water resources and in environmental protection policy. The main objectives are to understand and evaluate the water quantity and quality in order to provide water of appropriate quality to various water users. The water quantity was assessed by the measurement of runoff or discharge at specific river cross sections using floating method for surface water and bucket and stopwatch method for springs and boreholes. The quality of river water and spring was identified in terms of its physical, chemical, and biological parameters. The analyzed data were compared with standard values recommended by WHO. Macroinvertebrates were collected in the rivers using a plankton nets and 10 minutes of sampling. Identification was made at the laboratory of Malacology. Results revealed that the quality of water obtained from sampling points is generally good to use for different domestic purposes except the Idanta River and Rwembwe borehole, which need an appropriate treatment before use. All sampling points are located far from houses and latrines, which can contribute to fecal contamination. On the different sampling points, bathing and washing clothes were observed and could constitute the source of pollution of drinking water. In Idanta and Kamira Rivers animals used water for drinking while also people use this water for domestic and drinking. In the two sampling points high values of Escherichia coli were found. No pollutant-taxa tolerant were found in the two monitored rivers for macroinvertebrates. Since water quality and quantity remain a major challenge in rural areas, the government should provide safe water to the population around Mikeno sector after treatment using suitable techniques.
