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(2) Heat affects the rate at which chemical reactions 

 progress, and it can speed up the formation of undesirable 

 compounds or change dynamic chemical equilibria. It also 

 affects biochemical reactions and can result in a more 

 rapid depletion of the oxygen resources. If sufficient 

 heat is added, temperatures can be elevated enough to 

 sterilize the environment by killing all living organisms. 



(3) Environmental temperatures are important to the living 

 resources. Physiological processes such as reproduction, 

 development, and metabolism are temperature dependent. 



The range of many species of fishes and the species com- 

 position of communities are governed to a great extent by 

 the environmental temperature. Temperature anamolies also 

 can block the passage of anadromous fish, greatly reducing 

 future populations. 



(4) An increase in temperature can result in synergistic 

 action; that is, the simultaneous effects of separate agents 

 is greater than the total sum of individual effects. Prime 

 examples are increased toxicity of some materials, increases 

 in susceptibility of fish to diseases, and increased 

 virulence of fish pathogens. 



(5) Thermal pollution affects other aquatic organisms such as 

 the aquatic plants, the benthos, and the bacterial popula- 

 tions. Increased temperatures may reduce the numbers of 



