In this article we will discuss about:- 1. Introduction to Hydrosphere 2. Unique Properties of Water 3. Biological Method of Zonation 4. Lotic Environment 5. Lentic Environment 6. Nitrogen and Phosphorus Cycles 7. Complexion in Natural Water and Waste Water 8. Micro-Organic – The Catalyst of Aquatic Chemical Reactions 9. Nitrogen Fixation 10. Eutrophication 11. […]