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Water Pollution Sustainably managing a Renewable Resource OUTLINE of chapter 21. Surface Water Pollution Groundwater Pollution Ocean Pollution Water Pollution Control Spotlight on Sustainable Development Cleaning Up the Great Lakes Why water is important ? The majority of the cells in our body are made up of water. Water is the primary component of our saliva, sweat, and tears. It makes up a big portion of our blood and lymph systems. It transports food and oxygen to different cells and carries wastes out of our bodies. It controls our blood pressure by balancing our bodies’ electrolytes. It helps the kidneys flush out toxic substances. It moistens our mouth, nasal passages, and eyes. It helps regulate our body temperature. It keeps us cool when the weather is hot and it insulates our bodies from cold weather. It serves as a shock absorber or cushion for our organs. It serves as a lubricant for our joints so we can move comfortably. It provides us with many minerals that our body needs. SURFACE WATER POLLUTION Water pollution is any physical or chemical change in water that adversely affects organisms. Like many other problems, it is global in scope, but the types of pollution vary according to a country's level of development. SOURCES OF WATER POLLUTION: 1. Natural Sources: Rain,　Snowfall, Leaching, river, etc. 2. Anthropogenic Sources: Industrial sources Domestic Sources Agricultural Sources Mining Sources Physical Pollutant (thermal and radioactive sustainable). Water pollution comes from either a POINT or a NONPOINT SOURCE. Waste water characterization: 1. Physical 2. Chemical 3. Biological 1. Physical Characteristics: Colour Odour Turbidity Temperature Solids 2. Chemical characteristic: PH Alkalinity Inorganic constituents like chlorides, heavy metals, nitrogen, Phosphorus, etc. Dissolved Oxygen (DO) Biochemical Oxygen Demand (BOD) Chemical Oxygen Demand (COD) Pollution Spill, South Florida POLLUTANTS FOUND IN RUNOFF Organic and Inorganic Nutrients INORGANIC NUTRIENTS—NITRATES AND PHOSPHATES Inorganic nutrients stimulate excess plant growth, which impairs navigation and swimming and disrupts the aquatic environment. When the plants die, they decompose, causing oxygen levels to decline precipitously—an effect that can be harmful to a host of organisms. EUTROPHICATION AND NATURAL SUCCESSION The accumulation of nutrients in lakes, from both natural and human sources, is called natural and cultural eutrophication, respectively. Combined with the deposition of sediment from human activities, cultural eutrophication causes lakes to age prematurely. Natural eutrophication Natural eutrophication is usually a fairly slow and gradual process, occurring over a period of many centuries. It occurs naturally when for some reason, production and consumption within the lake do not cancel each other out and the lake slowly becomes over fertRead less