The standard has been designed specifically for use in determining the carbon assimilation of plankton algae (DS 293). At the same time, the penetration of irradiance into the water, characterized by the vertical attenuation coefficient, can be included as an element in the assessment of water quality. The standard is structured with a main part and two annexes. The main part describes a method for measuring and calculating downward photosynthesis-active irradiance in different water depths, including calculation of the vertical attenuation coefficient. The method can be used in all fresh and marine water types. Annex A describes a method for determining photosynthesis-active irradiance in incubators. Annex B lists the symbols used for irradiance parameters.
DS 294:1983 history
1983DS 294:1983 Determination of photosynthetically active irradiance in water