Spectrophotometric Determination of Nutrients Using Principal Component Regression

Certain environmental factors such as salinity, dissolved oxygen and chlorophyll concentration can be measured by electric or optical sensors, enabling continuous and automatic measurement with high resolution in time and space. Such measurement is of great importance in the monitoring of marine environments. In order to understand the ecosystem of the sea in detail, the distribution of and changes in nutrient concentrations should be measured in terms of primary production. Generally, since seawater contains high concentrations of chloride, bromide and so on, nutrients must be extracted from these ions. Automatic measurement has therefore proven difficult, and water sampling and chemical analysis in a laboratory are required. This paper proposes a simplified method for measuring nitroxide concentration in seawater using ultraviolet spectrometry and principal component regression (PCR). The present method is shown to be superior to the conventional one since it does not require chemical processing or filtration of seawater.Copyright © 2009 by ASME