SolarStat (TM)

About

Description A new laboratory device has been developed at the UC San Diego Scripps Institution of Oceanography for the quantitative study of micro algae under simulated photic conditions as would be found, for example, in outdoor raceway ponds or natural shade-limiting growth environments. Such shade-limiting environments involve exposure to fluctuating light, whereby individual cells are mixed through a light gradient of very high light near the “pond surface” and no light near the “pond bottom”. Software allows choice for a variety of daily irradiance waveform patterns, with in situ incident intensities capable of >3000 Ein m-2 s-1. Little loss of irradiance to outside the sample chamber occurs from the perpendicular scatter of incident irradiance that allows the accurate measure of net photosynthetic efficiency.  The optically coherent properties of irradiance inside the culture vessel permit the study of shade-limiting algal growth dynamics in a quantitative manner under defined, quanta-determined conditions. The geometry of the culture vessel allows deep water columns (typically 10-40 cm, but deeper or shallower depths can be used) to have minimal volumes, providing low maintenance and low operational costs. Prototypes of individual and grouped units have a small footprint for bench top use. Prototypes have cultivated micro algae using batch and a variety of continuous culture techniques.   Advantages The device has unique advantage over current laboratory micro algae cultivation systems used to study photosynthesis by its containment of known light quantity in a deep water column, as would be compared with commercial units that conventionally irradiate cultures either from the side (thus requiring very wide cultivation vessels to attenuate light completely), or from the top (resulting with serious culture-surface related artifacts).