Water quality of streams associated with artisanal gold mining; Suárez, Department of Cauca, Colombia.

Gold mining is one of the major problems of contamination of hydric resources in Colombia, this practice generates a high impact on water quality due to the accumulation of waste during its process. In this study water quality was evaluated in five natural stream beds corresponding to four streams with gold mining operations and one in the Cauca River, taking samples before the water inlet and after the outlet in each operation in the streams of Dios Te Dé, Tamboral, Piedra Imán, and Lorenzo affected by artisanal gold mining labor, which drain into the Salvajina Reservoir on the Cauca River in the municipality of Suárez Cauca, Colombia. Characterization of water bodies in the streams was carried out applying contamination indices of Colombia. The IDEAM protocol was used as guide to monitor the water currents. Samples were taken in 15 stations in the natural stream beds with operations and a sampling station on the Cauca River after the reservoir in these lotic ecosystems, during three periods; two from 2018 and one from 2019. The range of the contamination indices according to the environmental variables were considered. Results show that the contaminants associated with TSS, TUR, and Hg are high in the sampling stations in the output of the operations and the sampling stations of the streams with influence on the operations (T3, T4, I2, I3, D2, and D5). The water quality score according to the ICA IDEAM index varied between acceptable and regular in the different sampling stations. However the Hg concentration in sampling station C1 of the Cauca River is due to contributions from the operations in the amalgamation process. This requires strategic interventions by the communities, miners, operation owners, and control organisms as the Regional Autonomous Corporation of Cauca (CRC) and the Ministry of Environment and Sustainable Development (MADS) to minimize the negative impacts on the hydric resource and ecosystemic services associated with this resource.

Fish farm and water quality management / Piscicultura e manejo da qualidade da água

Fish farms water quality management is analyzed with regard to the management employed and the different trophic states are compared within the system during the dry and rainy seasons. Six sites were marked two in the water supply (P1 and P2), and four within the fish farm (P3 to P6). Whereas sites P1 and P2 (water supply) were characterized as oligotrophic, the others were mesotrophic and eutrotrophic sites. Environmental variables, mainly nutrients, conductivity, COD, BOD5 and TSS tended to increase as from P3 due to management and fertilization. Greater impact has been registered in the fish farm under analysis for variables COD, ammonia, total phosphorus and TSS during the discharge and pond emptying period. Frequent monitoring of water quality should be undertaken in fish breeding and plankton production ponds, especially in those close to P3 and P4. Removal of sediment in decantation lake or P5 is also recommended to decrease nutrient concentrations, especially phosphorus, accumulated on the bottom soil.(AU)

Este estudo objetivou avaliar a qualidade da لgua em uma piscicultura em funçمo do manejo adotado e comparar os diferentes graus de trofia dentro deste sistema nas estaçُes de seca e chuva. Seis pontos foram delimitados sendo dois na لgua de abastecimento (P1 e P2) e quatro dentro da piscicultura (P3 ao P6). Os pontos P1 e P2 foram caracterizados como oligotrَficos e os demais como mesotrَficos e eutrَficos. Houve tendência das variلveis ambientais principalmente, nutrientes, condutividade, DQO, DBO5 e STS aumentarem a partir do P3 em funçمo do efeito do manejo e fertilizaçمo. As variلveis DQO, amônia, fَsforo e STS foram de grande impacto dentro da piscicultura estudada, principalmente, no perيodo de descarga e esvaziamento dos viveiros e tanques. Frequente monitoramento da qualidade da لgua deve ser realizado nos viveiros de criaçمo de peixes e nos tanques de produçمo de plâncton, especialmente naqueles prَximos aos pontos P3 e P4. Outra recomendaçمo a ser adotada é a remoçمo do sedimento na lagoa de decantaçمo (P5) devido ao grande acْmulo de fَsforo neste local.(AU)

Fish farm and water quality management / Piscicultura e manejo da qualidade da água

Fish farms' water quality management is analyzed with regard to the management employed and the different trophic states are compared within the system during the dry and rainy seasons. Six sites were marked two in the water supply (P1 and P2), and four within the fish farm (P3 to P6). Whereas sites P1 and P2 (water supply) were characterized as oligotrophic, the others were mesotrophic and eutrotrophic sites. Environmental variables, mainly nutrients, conductivity, COD, BOD5 and TSS tended to increase as from P3 due to management and fertilization. Greater impact has been registered in the fish farm under analysis for variables COD, ammonia, total phosphorus and TSS during the discharge and pond emptying period. Frequent monitoring of water quality should be undertaken in fish breeding and plankton production ponds, especially in those close to P3 and P4. Removal of sediment in decantation lake or P5 is also recommended to decrease nutrient concentrations, especially phosphorus, accumulated on the bottom soil.

Este estudo objetivou avaliar a qualidade da água em uma piscicultura em função do manejo adotado e comparar os diferentes graus de trofia dentro deste sistema nas estações de seca e chuva. Seis pontos foram delimitados sendo dois na água de abastecimento (P1 e P2) e quatro dentro da piscicultura (P3 ao P6). Os pontos P1 e P2 foram caracterizados como oligotróficos e os demais como mesotróficos e eutróficos. Houve tendência das variáveis ambientais principalmente, nutrientes, condutividade, DQO, DBO5 e STS aumentarem a partir do P3 em função do efeito do manejo e fertilização. As variáveis DQO, amônia, fósforo e STS foram de grande impacto dentro da piscicultura estudada, principalmente, no período de descarga e esvaziamento dos viveiros e tanques. Frequente monitoramento da qualidade da água deve ser realizado nos viveiros de criação de peixes e nos tanques de produção de plâncton, especialmente naqueles próximos aos pontos P3 e P4. Outra recomendação a ser adotada é a remoção do sedimento na lagoa de decantação (P5) devido ao grande acúmulo de fósforo neste local.