gradients. While the metrics used for an IB! should be selected for broad applicability (e.g., Kerans & Karr 

 1994), not all applications of the original IBI concept have followed this tenet. 



The purpose of monitoring the condition of estuaries on a regional scale was to provide environmental managers 

 with an estimate of baseline conditions. EMAP-E provides regional estimates of estuarine condition against 

 which local managers can compare their estuaries. This further emphasizes the need to evaluate an indicator 

 in the context of a specific monitoring program, as an indicator that may be ideal for one type of program may 

 be inappropriate for another. In this case, the indicator itself could be applied to other, more spatially-specific, 

 monitoring programs if alternative methods were employed. The benthic index in this context is of high value 

 to environmental managers, especially to those concerned with estimating biotic or ecological condition in a 

 quantitative manner. 



References 



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