What Factors Affect Water Quality

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There are many factors that affect water quality. The pH of water, the dissolved oxygen level, amounts of phosphates and nitrates in the water, and pollutants are some of these factors. The water quality of rivers and lakes are important because we often get our drinking water from them, animals and plants depend on them for survival, we use water for recreation, and rivers and lakes are often connected to bigger bodies of water. If water quality is not maintained, the environment isn’t the only thing that will suffer. The commercial and recreational value of water resources will also decrease.

The pH of a substance is essentially the samples acidity; however it is actually the potential activity of hydrogen ions. The pH scale runs from
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A dissolved oxygen level that is too high or too low can affect the water quality and aquatic life. Oxygen can enter the water in various forms. One way oxygen enters the water is through the air. From the air oxygen slowly diffuses across the waters surface from the atmosphere or through aeration, whether natural or human made. The aeration of water can be caused by wind that creates waves, rapids, waterfalls, ground water drainage or any other form of running water. Man made causes include aquarium air pumps or large dams ("Dissolved Oxygen and Water Quality," n.d.). Dissolved oxygen is also produced as a waste product of photosynthesis. The amount of dissolved oxygen often determines the amount of fish and other organisms living in that particular body of water. If the dissolved oxygen level drops below 5.0 mg/l, aquatic life starts to become effected. Oxygen levels below 1-2 mg/l for a few hours can kill fish. The amount of dissolved oxygen depends on temperature, pressure and salinity. The solubility of oxygen decreases as the temperature increases. Also dissolved oxygen decreases as the salt levels increase. Due to this salt water holds about 20 percent less dissolved oxygen than freshwater if the sample had the same temperature and pressure. Lastly dissolved oxygen will increase as the pressure increases. Water at lower altitudes can potentially hold more dissolved oxygen than higher levels. However, due to microbial …show more content…
However plants and algae use nitrates as a source of food. Large amounts of algae cause dissolved oxygen levels to fall. Nitrogen is essential for all living things. Nitrogen helps form DNA and proteins found in cells. Animals get nitrogen by eating plants and other animals. Plants get nitrogen through water and soil. They absorb it in the form of nitrates and ammonium. When aquatic organisms excrete waist and when plants die ammonia is created. Bacteria in the water can change ammonia to produce nitrite, which is converted by a different kind of bacteria to create nitrate. Nitrates also come from the earth; soil contains organic compounds, which contains nitrogen compounds. Any excess nitrate in the water is food for aquatic plants such as algae. This creates an excess amount of plants, which can be dangerous to aquatic life. Excess amounts of nitrates usually cause high levels of dissolved oxygen during the day and low levels at night due to the plants undergoing photosynthesis. This in turn creates stress for fish, causing them to act irregularly and not reproduce. Fish and aquatic insects can also be affected by large amounts of algae. When the algae dies, it will settle on the bottom of the bank where bacteria can feed. These bacteria consume oxygen and cause the dissolved oxygen levels to decrease (“Nitrates and their effect on water

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