SIMPLE ELECTROMETRIC METHODS FOR ESTIMATING MICROBIAL ACTIVITY IN AQUACULTURE PONDS

Simple electrometric methods were tested to estimate microbial activit y in hypereutrophic aquaculture ponds using equipment common at aquacu lture facilities for biochemical oxygen demand (BOD) measurements. Act ivity measurements tested included net photosynthesis based on changes in dissolved oxygen (DO) concentrations in samples incubated under li ght and dark conditions; general microbial activity as indicated by ox ygen consumption rates in the dark; nutrient limitations as indicated by changes in DO consumption rates with nutrient additions; and nitrif ication based on the difference in DO consumption rates between sample s incubated with and without a nitrification inhibitor. Method evaluat ions in intensive shrimp culture ponds suggest that simple electrometr ic methods are a good index of water column microbial activity under a range of conditions. (C) 1998 Published by Elsevier Science B.V. All rights reserved.