AbstractsBiology & Animal Science

Temperature is the main controller of in-stream progression when it relates to metabolism of plants and animals, microbial decomposition of organic matter, solubility of air and water exchange of gases (Thyssen, 1987). However there are so many factors that could bring about low and high stream temperatures that lead to significant ecological variation in running waters. The major drivers as observed from the experiments conducted reveals that as water travels downstream, the temperature increases until a point where water temperature reaches equilibrium with air temperature. However, precipitation as observed influences the water level and invariably changes the water temperature. Some studies revealed that water temperatures above 17°C generally decrease the metabolic activity of brown trout, and at temperatures above 22°C there is a breakdown of vital body processes.