581 



necessary for plant growth. These nutrients in moderation and in 

 proper balance make possible the normal algal productivity which, 

 m turn, supports all animal life. In excess or imbalance, these nutrients 

 permit or encourage eutrophication, the accelerated superabundance 

 of algae to nuisance conditions. Bacteria are responsible for causing 

 foul odors, unacceptable bottom conditions, digusting slimes that foul 

 fishermen's nets, and depletion of dissolved oxygen in the water which 

 drives out fish and other desiraible organisms. Bacteria, protozoans, 

 and viruses are extremely important as disease organisms, both to 

 humans and to desirable estuarine plants and animals. 



ALGAL GROWTH PROCESSES 



As more and more studies determine that eutrophication is a major 

 current or potential concern in our estuaries, it is imperative that we 

 seek to understand the cause-effect relationships governing algal 

 growth processes. Both field and laboratory studies are required. The 

 actual impact of nutrients on estuarine eutrophication problems must 

 be understood. We must establish the major nutrient concentrations 

 allowable in various estuaries based on watershed characteristics, 

 influent stream concentrations, and the overall watershed management 

 policies. An approach often overlooked on this topic is the comple- 

 mentary use of experimental studies and modeling techniques in which 

 each is employed to direct the development of the other in the same 

 way as computer analyses and test flights have interacted in the space 

 program. Certainly, more knowledge will have to be developed about 

 the rates and conditions under which organic material is mineralized 

 by bacteria to the active chemical stage where it can be reincorporated 

 into new plant material. 



ECOLOGY AND ENVIRONMENTAL REQUIREMENTS OF MARINE BACTERIA 



Detailed knowledge of the environmental requirements and eco- 

 logical relationships of marine benthic bacteria and of attached algal 

 forms as well las the free-living and more economically important 

 marine species is necessary to insure that environmental changes al- 

 lowed do not effect water use at a point many biological steps removed 

 from the initial effect. Studies of factors involved in natural popula- 

 tion succession and natural fluctuations in populations of a single 

 species and/or a community of species are required when it becomes 

 desirable to control these natural changes. It is certainly necessary to 

 recognize them as factors affecting management of natural resources. 

 It must be borne in mind that bacteria themselves are an exceedingly 

 valuable prey species as well as is the phytoplankton whose develop- 

 ment is made possible by the mineralization activity of bacteria. 



The use of indicator hacteria 



In order to assess biological contamination and potential health 

 hazards in estuaries, adequate bacterial assay techniques are necessary. 

 The use of indicator bacteria, mainly fecal coliforms, is the inajor and 

 most widely used detection system. Current water quality criteria for 

 contact recreational waters place emphasis on fecal coliform data and 

 consider this group to be a more realistic indicator than total coliforms 



