Aquatic ecology and Biodiversity

Unit 9- Freshwater environment

9.3.3. Lotic habitats

Lotic habitats are called running water systems including streams and rivers. These water bodies are different from the lentic systems by the following factors
Factors influencing rivers
•Movement of water is the unique characteristic of lotic systems while the same is absent in the lentic systems. The flow of water is unidirectional.
•The interchange between the soil and water is higher in the lotic waters than the lentic waters.
•Dissolved oxygen content is more and uniformly distributed in running waters and there is no physical and chemical stratification.
•Depending on the water movement in different zones, the nature of bottom materials is changing with sandy, muddy, rocky or pebbles.
Zonation in rivers
Three zones are recognized in rivers. They are the crenine zone, rithron zone and potamon zone.