What this work is about, in plain words
Why do algal cells contain fewer pigments in bright light? The authors proposed an explanation — a balance between pigment synthesis and destruction by light — and described it with equations.
Satellites and aircraft show where the ocean is rich in phytoplankton, but the instruments measure pigments, not biomass. To go from pigments to biomass, one needs to know how much pigment there is per unit of cell mass. This share varies greatly, and the main factor is light: the brighter it is, the fewer pigments the cells contain. The authors set out to explain this phenomenon.
The work is theoretical. The authors proposed a mechanism in which pigment content is determined by two opposing processes: the cell constantly synthesizes pigments, and light constantly destroys them (photodestruction). On this basis, a mathematical model was built that takes into account how many light quanta a pigment molecule must absorb to be destroyed.
According to the authors, equations were obtained that describe how the pigment content of biomass depends on light intensity. The coefficients in these equations have a clear biological and physical meaning and can serve as a characteristic of a species.
The work provides a theoretical basis for converting optical measurements into biomass estimates and for understanding how light conditions affect the pigment composition of cultures.
Limitations. This is the theoretical part of the series: testing the equations on experimental data is left to the authors' subsequent articles. The text of the article is available only as a scan; the explanation was written from the recognized text.