Dystrophic lake

Dystrophic lakes, also known as humic lakes, are lakes that contain high amounts of humic substances and organic acids. The presence of these substances causes the water to be brown in colour and have a generally low pH of around 4.0-6.0. Due to these acidic conditions, there is little biodiversity able to survive, consisting mostly of algae, phytoplankton, picoplankton, and bacteria. Ample research has been performed on the many dystrophic lakes located in Eastern Poland, but dystrophic lakes can be found in many areas of the world.