Compensation point

The light compensation point of a plant indicates at which the illuminance fixed by the Calvin cycle carbon dioxide and the precipitated when their breathing carbon dioxide are just the same. The illumination in this case indicates how much photosynthetically usable light, so make photons of wavelengths 400 to 700 nm per unit area and time on the plants.

This can also refer to the oxygen conversion: The light intensity at which the oxygen consumption by the respiration of a plant and the production of oxygen by photosynthesis keep the balance, the light compensation point.

If this is exceeded, is a net gain rather than in the carbon fixation. The plant can therefore only survive in illuminance levels above the compensation point.

By the light compensation point, sun plants and shade plants can be distinguished from each other. While reaching for solar plants, the light compensation point at relatively high illuminance, shade plants may have a net gain in carbon fixation under lower illuminance. In C4 plants, the illuminance at the light compensation point is higher than that of C3 plants, so they need much more light than C3 plants in order to exist. However, they are far superior at high illuminances the C3 plants in their photosynthetic rate.