vi-n4 



Oil 



Because of the increase in oil pollution and the associated use 

 of oil dispersants, it is urgent that a better understanding of 

 degradation processes involving both treated and untreated oil 

 spills be reached without delay. The extent and kinds of effects 

 exerted by oil dispersants must be known so that appropriate 

 reactions can be made when an oil -spill -induced emergency occurs. 

 For example, oil or petroleum concentration, per se^, at high 

 levels is considered deleterious to the ecosystem and maximum 

 levels of oil or grease are established for estuaries. However, 

 evidence from both the Torrey Canyon and Santa Barbara oil spills 

 indicate that some crudes and petroleum by-products are excellent 

 substrates for many organisms, becoming part of an enriched food 

 chain, while others may be either poisonous or have virtually no 

 food value. Thus, one must know not only how much oil and grease 

 Is present, but also their compositions and their effects on 

 important plants and animals. Much of the mortality in these 

 accidents was caused by the dispersant and not by the crude oil. 



NATURAL VARIABILITY 



A major gap in our knowledge of estuaries is an understanding of 

 natural variability. While there is a growing backlog of infor- 

 mation on natural variability within populations of certain 



