The investigation combines field monitoring with field, microcosm, and 

 laboratory experiments. The spatial distribution of variables in the bay is 

 relatively well established; we have been gathering time-series data in the bay 

 since early 1976. The outfall is due to be diverted shortly after this is written 

 (November 1977), and we anticipate continued collection of time-series data 

 for at least one year after the diversion. 



PROJECT DESIGN 



Kaneohe Bay is relatively well-described spatially, and methods by which 

 chemical and biological characteristics of marine environments are measured 

 are reasonably standardized. Therefore the analytical details of the study do 

 not need discussion at this juncture. Let us instead examine the conceptual 

 approach to this analysis. 



Sewage discharge presently imposes a large and well-documented loading of 

 biologically active materials on the ecosystem. The change of that discharge 

 volume with time is known, and the termination date of the discharge will be a 

 discrete, well-defined event. The discharged materials alter the water 

 composition near the discharge sites, become incorporated into the food web, 

 cycle within tlie ecosystem, and flush from the ecosystem. In addition to 

 biostimulatory responses from the fertilization of the ecosystem, there may be 

 responses from the loading of plant and/or animal toxins on the system. When 

 the discharge terminates, there will be ecosystem responses as both direct and 

 indirect ramifications of the sewage diversion. 



There are three main components to the present study. 



1. Routine field sampling, to document the sequence of chemical, plant, 

 and animal changes through time. This sequence may be divided into "before 

 diversion" and "after diversion" periods which may be compared as two 

 distinct statistical populations of data, each of which may show seasonal or 

 other temporal variations. The frequency of tiie time-series sampling is largely 

 dependent upon the assumed or documented time scale of variability. For 

 example, some water composition variables are measured one or more times 

 per week, while characteristics of the benthos are measured every two months. 

 Important adjuncts, to the routine monitoring are the utilization of available 

 Kaneohe Bay field data antecedent to our own, and use of data from 

 environments which may be comparable to Kaneohe Bay witli respect to some 

 (but not all) of the natural and artificial ecosystem characteristics. 



2. Field studies, designed to answer specific questions about the ecosystem. 

 These studies may also establish time sequences and spatial variations in the 



348 



