'Trophic' comes from Greek word for feeding. There are generally three classes distinguished:
Eutrophic (well-fed) means nutrient rich and is usually associated with high primary productivity and low oxygen levels;
Mesotrophic (medium) having intermediate levels of primary productivity; pertaining to water having intermediate levels of the minerals required by green plants;Oligotrophic (little-fed), nutrient-poor except for oxygen, low primary productivity. The trophic status for any one wetland is a condition determinated by the surrounding catchment, landform and geology.