2. INTRODUCTION Eutrophication is a natural phenomenon in which the water becomes green and degraded. It is a natural process which became a problem because of human activities. Human activities increases the rate of eutrophication in water bodies.

3. CAUSES (POINT SOURCES) Wastewater effluent (municipal and industrial) Runoff and leachate from waste disposal systems Runoff and infiltration from animal feedlots Runoff from mines, oil fields, unsewered industrial sites Overflows of combined storm and sanitary sewers Runoff from construction sites less than 20,000 m² (220,000 ft²) Untreated sewage

4. CAUSES (NON-POINT SOURCES) Runoff from agriculture/irrigation Runoff from pasture and range Urban runoff from unsewered areas Septic tank leachate Runoff from construction sites >20,000 m² Runoff from abandoned mines Atmospheric deposition over a water surface Other land activities generating contaminants

5. MECHANISM

6. EFFECTS Reduce quality of water Submerged aquatic vegetation Oxygen depletion Growth of Aquatic Plants Species Changes Enhanced Internal Recycling of Nutrients Elevated Nitrate Concentrations Increased Incidence of Water-related Diseases Increased Fish Yields

7. IMPACTS Decreased biodiversity New species invasion Toxicity

8. MITIGATION RIPARIAN BUFFER ZONES PREVENTION POLICIES 1. Technologies 2. Waste dispose technology 3. Public participation 4. Economic instruments NITROGEN TESTING AND MODELLING ORGANIC FARMING