Combined effects of three metals were assessed through toxicological tests in binary and one tertiary mixtures. Death and changes in body weight were used as biological responses to the toxicity. Test solutions were prepared with metal salts grade Merck Analar at 65%. Concentrations were derived from the Congolese official standards from Mining Code and Regulations. These were 500 ppb fof Cd, 5000 ppb for Pb and 5000 ppb for Al. Acute tests were 96-h exposures of the Mosquito fish Gambusia affinis and chronic tests were based on the 35-d exposures. During the chronic exposure, fish were daily fed with the powder of the earthworm Eisenia fetida.Results allowed to conclude that:- Legal standards from the Congolese code were toxic to fish. They should be reduced or lowered.- Mixtures of Cd and Pb develop synergism and remain very toxic to aquatic organisms.- Mixtures of both metals with the Al in binary or tertiary combinations showed antagonism.This information provides useful tools to water quality managers.
The water of the river N’djili is used for several facts. Indeed, due to a lack of the servicing in drinking water in several districts of the city of Kinshasa, several residents use the water of this river as water of bathing, of cooking, of washing of linens, of drink, of watering of the gardens and washing of the gardening products (vegetables and tubers), etc. There is place to underline that biggest user of the water of the river N’djili is the REGIDESO that extracts every day a nominal volume equivalent to ±550.000 m3 of raw water in order to purify it to go against at least ¾ of the population of Kinshasa in drinking water. Yet several human activities susceptible to damage the quality of the water of this river are identified in its perimeters very brought closer. The danger is that in case of pollution of the river N’djili, several score of thousands of Kinshasa’s population should be exposed directly to water illnesses with risk of the epidemiological propagation, while the REGIDESO will be obliging to use big quantities of reagents to succeed in purifying this water polluted without forgetting the risk of resistance of some badly known pollutants. It will be able to be obliged however to resort to a lot of more refined techniques and expensive. A resource of as big importance had to absolutely be protected while the activities capable to harm to its good working should be regulated restricted either.
The environment (middle) of three important sites of catchment of water of the REGIDESO in Kinshasa notably the rivers N’djili and Lukunga and the Congo stream is in particular vulnerable following the failure to respect of the environmental hygiene by the riparian populations of these three sites and of all kinois in general. This survey proposes to verify the degree of water pollution treated by the REGIDESO and the efficiency of the treatment techniques applied by this one to purify water. For that to make, 3 samples by site of the raw water and three of water treated have been appropriated and have been analyzed in order to determine the physic-chemical parameters (MO, MES, Turbudité, pH, T°, SD, Co, NO-3, PO 4, FeT, Pb, OD, DBO5 and DCO) and bacteriological (fecal coliforms, fecal streptococci and Escherichia Colis) for the raw water, while for the treated water, it has about of the analysis of the data base of the laboratory of the REGIDESO.
The gotten results show that the dismissals descended of the human activities upstream of the sources of catchment have negative impacts on water to treat and that some parameters as the total iron, the DCO and the MY don't answer the norms of the drinking water. Otherwise, the meticulous exam on one period of one year of the archives of the laboratory of the REGIDESO indicates some temporary, daily or periodic failings as for the bacteriology.
This study aims to assess of importance of different environments (forest, river, planting, fallow, town and village) and categories of use and activities (fishing, hunting, pharmacopoeia, construction, ritual, food, tools and firewood) for the Batwa and Bantu living in Bikoro area. The interest of this study is to provide a comprehensive diagnosis that reflects the priorities and what is important from the perspective of forest people. To do so, comparative and synchronic study among the Bantu and Batwa in Iyanda and Moheli were conducted, two area in Lake Ntomba sector. Stones Distribution Method is applied to (SDM) methodology developed by CIFOR. So we thought that farming practice is likely to involve a reduction in the use of wild plants, the results of this study show that forests today still hold an important place in the daily lives of Batwa but also in that of their non-Pygmy neighbors. And that, including food: mushrooms and fruits are significant food supplements, which allow a more varied diet with the seasons. However, today, after a relatively old settlement and a long coexistence with non-pygmies, agriculture is also a priority.
The Pygmies are knowledgeable of the virtues of the biodiversity of their environment, including the food value of these species. This study report on food strategy developed by the Batwa and is based on a rich biodiversity. We conducted a household survey of 260 Batwa in five villages in Bikoro territory, Democratic Republic of Congo. The results of this survey show that 105 edible wild plants are recognized by the Batwa even if only 65 are actually used in the diet of the Batwa. Animal Genetic Resources and Other Non-timber Forest Products are also very diverse. However, there is currently in the region to a scarcity of natural resources, particularly due to the uncontrolled harvesting, expansion of agriculture due to strong population growth and logging.
This study reports on changes in traditional knowledge and know-how in Batwa communities due to livelihood changes especially due to cassava cultivation ownership. We compare Batwa (pygmies) and Ntomba (bantou) communities living in the two villages (Iyanda and Sekri) in Congolese jungle. Results revealed that Batwa communities have lost significant knowledge packages after they adopted bantou livelihood behavior. This situation should be well managed to avoid the complete loss of Batwa traditional knowledges and know-how.