Lake ecosystem productivity, defined by the rate of biomass synthesis, is believed to be limited by nutrient availability. However, the comparison of several small unproductive lakes along a water colour gradient now shows that coloured terrestrial organic matter controls the key process for new biomass synthesis through its effects on light attenuation, suggesting that light is the more important limiting factor.
- Jan Karlsson
- Pär Byström
- Mats Jansson
