What effect do high-temperature discharges have on bacterial populations?

High-temperature discharges negatively impact bacterial populations by causing shifts in their composition. Bacteria have specific temperature ranges in which they thrive, and when temperatures exceed these ranges, certain types of bacteria may be favored over others. For instance, thermophilic bacteria, which thrive in high temperatures, may proliferate, while mesophilic bacteria, which prefer moderate temperatures, could decline in number. This shift can alter the dynamics of the ecosystem, affecting processes like nutrient cycling and organic matter breakdown. Therefore, the correct answer emphasizes that high-temperature discharges can lead to a change in the types of bacteria present in a given environment, rather than just affecting biomass or nutrient uptake directly.