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Nature of ecosystems. Energy flow – microbes are decomposers Water Carbon Nitrogen. Nitrogen Fixing Bacteria. Nitrifying Bacteria N 2 to NH 3 Cyanobacteria Methylotrophic bacteria Rhizobium – symbiotic. Water Pollution. Chemical Biological Indicator organism – E. coli.
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Nature of ecosystems • Energy flow – microbes are decomposers • Water • Carbon • Nitrogen
Nitrogen Fixing Bacteria • Nitrifying Bacteria • N2 to NH3 • Cyanobacteria • Methylotrophic bacteria • Rhizobium – symbiotic
Water Pollution • Chemical • Biological • Indicator organism – E. coli
Coliform Tests • Membrane Test • Water is filtered • ______________ is placed on agar • Colonies are counted • MUG (ONPG) Test • Fluorescence (yellow color) indicates E. coli presence
Sewage Treatment • Sewage – used water • Primary • Solids separated from liquid • Floating ____________ is shredded • Skimmers remove ___________________ • ___________________ recovered • Organic solids (__________) removed
Trickling filtration Sewage aerated by spraying Moves over a layer of aerobic microbes on rocks 80% removal of organic matter (BOD) Activated sludge treatment Air is pumped into liquid in a tank Microbes are added as a sludge and decompose organic material Secondary Sewage treatment
Tertiary Sewage Treatment • Filters can remove the last 5-20% of organics • Costly process • Applications: