Lab 5: Calculating WQI and Capstone Project Flashcards
What is total phosphate a limiting factor in?
Plant and algal growth
Excess phosphorus causes what?
Eutrophication. Eutrophication can lower the levels of dissolved oxygen in the water and can render the water uninhabitable by many aquatic organisms. Phosphorus is often the limiting factor that determines the level of eutrophication that occurs. High levels of phosphates are associated with increased BOD and decreased DO.
What are the four classifications of phosphates?
Orthophosphates, organically bound phosphates, condensed phosphates (also called polyphosphates), and total phosphates.
What are orthophosphates?
Inorganic forms of phosphate. These are the forms of phosphates used heavily in fertilizers and are often introduced to surface waters through runoff.
What are organically bound phosphates?
Found in human and animal wastes or in decaying organic matter.
What are condensed phosphates (also called polyphosphates)?
Sometimes added to water supplies and industrial processes to prevent the formation of scaling and to inhibit corrosion. This is the form of phosphate that was commonly found in detergents in the past.
What are total phosphates?
The sum of all three of the forms described above. This is the most commonly reported form of phosphate concentration.
How is the concentration of phosphates expressed in units?
mg/L PO4-P
How are phosphates added to the water?
Humans add phosphates to water through industrial and agricultural wastes. Fertilizers contain high levels of phosphates and will enter the water by means of runoff and soil erosion. In areas where land and vegetation have been disturbed, soil erosion will increase. This will lead to even more phosphates being washed out of the soil and into the water. Phosphates also come from the excrement of animals living in or near the water.
