A-2 

 ADAPTATION 



Change in the structure, form or habits of an 

 organism to better fit changed or existing 

 environmental conditions. (See Acclimation) 



AEROBIC 



Refers to life or processes occurring only in 

 the presence of free oxygen; refers to a 

 condition characterized by an excess of free 

 oxygen in the aquatic environment. (See 

 Anaerobic) 



ALGAE (Alga) 



Simple plants, many microscopic, containing 

 chlorophyll . Algae form the base of the 

 food chain in aquatic environments. Some 

 species may create a nuisance when environmental 

 conditions are suitable for prolific growth. 



ALLOCHTHONOUS 



Pertaining to those substances, materials or 

 organisms in a waterway which originate outside 

 and are brought into the waterway. (See 

 Autochthonous ^ 



ALLUVIAL 



Pertaining to material that is transported 

 and deposited by running water. 



ALLUVIAL FAN 



(Delta) 



ANABOLISM 



Synthesis or manufacture of organic compounds 

 within an organism. (See Metabolism) 



