EESA11H3 Lecture Notes - Lecture 7: Gonyaulax, Thermal Pollution, Nitrification
5 Apr 2017
School
Department
Course
Professor
Document Summary
Sources and pathways of water pollution: agriculture growing corps, agriculture animal operations, timber-cutting operations, construction cities, cities/suburbs (paved surfaces, industrial outfalls, mining operations. Two major types of water pollution: point source specific spot (pipe, ditch, ship or smokestack, nonpoint sources runoff across large areas, urban areas (streets, parking lots, roofs), rural (agriculture, logging, mining sites) Sewage pollution: sanitary sewer wastewater from homes/commercial places to a treatment plant, storm sewer carries street runoff, combined sewer carries both sanitary wastewater and storm runoff heavy storms (discharges into the water bodies) Atmospheric deposition upon land and water: non-point source pollution. Conventional pollutions: biochemical oxygen demand (bod) Dissolved oxygen (do) needed for microorganisms to decompose waste. 6mg/l of do for high temperature and salinity. Lots of sewage = high bod= less oxygen available. Hypoxic (low oxygen) conditions fish moves away but crabs and snails may die. Bacteria are capable of oxidizing ammonia to nitrite and subsequently to nitrate (starts 6-7 days after cbod)
