Temporal Variance Function for Total Phosphorus Concentration

Abstract

General relationships between means and variances can be used to determine requisite sample number for desired levels of precision but have not been developed for phosphorus, one of the best indicators of lake eutrophication. Data from 65 north-temperate lake-years are used to compare such relationships of temporal variance as functions of mean concentration for both total phosphorus (TP) and chlorophyll a (Chl a). We found TP to be less seasonally variable than Chl a, confirming several regional analyses and strengthening the established recommendations that variability in Chl a should dictate sampling program design.