• Microbes in their Environment
• Microbe-Microbe Interactions
• Biogeochemistry (Cycling of Elements)
• Microbe-Higher Organism Interactions
• Environmental Pollution Control
Actinomycete amensalism of parasitic fungi
Anaerobic Carbon Use
• Oxygen supply limited by mineral particle size, organic matter content and water content.
• Plant roots may also add oxygen to deeper soils or anaerobic soils.
• Water saturation leads to anaerobic conditions and increased denitrification.
• Distribution of microbes depends on organic matter supply and source (humus and root exudates)
Geosmin = “earthy smell”
Ectomycorrhizal association between
( Pseuditsuga menziesii ) and a boletus-like mushroom
( Suillus caerulescens).
Nodule formed by
It’s a 100+ liter cellulose-degrading methane-producing microbial incubation.
There are only a few manned submersibles in the world that can explore hydrothermal vent communities (e.g. Alvin )
Control Point Sources
• Raw Sewage (99.9% water to 0.1% waste)
• Pollutants in sewage are:
– Debris and grit
– Particulate organic material
– Colloidal and dissolved organic material
– Dissolved inorganic material
– Human Pathogens
– Toxic Chemicals
• Preliminary (physical screening)
• Primary (physically settle solids)
• Secondary (biological)
– Remove organics aerobicaly (lower BOD)
– Solids production (separate water and “sludge”)
– Sludge Treatment (solids reduced)
• Tertiary (biological or chemical “polishing”)
– Biological nutrient removal systems
– Pathogen removal by chlorine or ozone
– Chemical nutrient removal (costly)
Activated Sludge (aerobic)
Trickle Filters (aerobic)
Anaerobic Sludge Digesters
What da Floc?
• Bacterial growth in activated sludge digested (aerobic) will aggregate (floc).
• Dissolved organics aggregate with bacterial growth and removed from the water.
• Imbalances may cause growth of filamentous bacteria or fungi; prevents settling; called “bulking”.
Anaerobic Sludge Digester
What’s a coliform? Why test them? How can we test for them?