Table 2. Mean annual flow. zinc. BOD5, for AVTEX's effluent from 

 1972 to 1977 



4.0- 



3.0 



S 2.0- 



1.0- 



1 2 3 4 



7 



6 7 8 



Stations 



9 10 11 12 



Figure 7. Comparison of macroinvertebrate community diversity (d) for the 1 970 and 

 1978 South River surveys. 



What sort of system properties might be useful in establishing baseline conditions? 

 An illustrative list follows: (1) productivity, (2) nutrient cycling or spiraling, (3) 

 biomass. (4) diversity, (5) decomposition or detritus processing, (6) properties con- 

 tributing to stability, such as resiliency, elasticity, and resistance to stress, and (7) 

 spatial relationships of various types. 



Additionally, a number of general concepts which are applicable to nearly all 

 ecosystems should be kept in mind when gathering data. Some of the biological 

 parameters that might be useful are mortality, reproductive success, growth rate, 

 genetic variability, nutrient flow, and partition coefficients. Some of the ways in 

 which alteration from desired conditions might be documented include alterations 

 in: population size, age distribution, species interactions, and spatial distribution. 

 Deleterious effects might also be recognized by life history table changes, alterations 

 in population turnover rates, or in alterations of functional parameters such as: 

 turnover rates in nutrients, rates at which storage of nutrients and other materials in 

 sinks become altered, and so on. 



233 



