Seasonal Variation of Major Elements in South Lake Cyohoha, Rwanda

The paper analyzed the seasonal variation of the concentrations of Cr, Mn, Al, N, P, As, Ba, Ca, Cu, Fe, Mg, and K in South Lake Cyohoha water using spectroscopic technique. Water samples were taken monthly at Ngenda, Karehe and Nyamabuye stations from January 2009 to December 2010. The results showed that the concentrations of aluminum, nitrogen, potassium, arsenic, phosphorous, manganese, chromium, barium and copper were high during the raining season and low during the dry season, while calcium, iron and magnesium varied independently with seasonal change. The results of conductivity and pH also confirmed the effects of seasonal change on the quality of water in the South Lake Cyohoha since the highest value of conductivity was found during the raining season, while the smallest was observed during the dry season, for pH the highest number was noticed during the dry season and the lowest during the raining season.