Shipboard Analysis of Soluble Nutrients in Lake Water Versus Analysis After Storage

"Water samples were collected from Lake Ontario during April and November, filtered (0.45 æm) and immediately analyzed onboard ship for the nutrients soluble reactive phosphorus, nitrate plus nitrite, and ammonia. Replicates were stored in glass bottles at 4°C and reanalyzed within eight days. Statistical analysis showed that soluble reactive phosphorus decreased by 11% and 13% and nitrate plus nitrite by 7% and 6%, whereas ammonia increased by 75% on one cruise and decreased by 37% on the other"--Abstract, p. v