Plant analysis is one of several techniques suggested or 

 in use for nutrient assay in natural waters. This seems 

 a highly appropriate time to evaluate these various tech- 

 niques and to compare them with plant analysis. Chemical 

 analyses of water samples, 1 4 C uptake following nutrient 

 enrichment, the Provisional Algal Assay Procedure, and 

 enzyme assays such as the measure of phosphorus deficiency 

 in plants by phosphatase activity are among the techniques 

 that should be compared. 



