-
Pollution from organic sources
- Correct decomposition overview
- Dead stuff and detritus
- decomposed by bacteria and fungi
- Microbial loop in plankton
- Food for other organisms
- OR decomposed-> encrusted detritus becomes food for other organisms
-
What goes wrong with natural decomposition
- Nature, can get stagnant anoxic areas in stratified places
- In anoxic areas, get anaerobic bacteria, sulphur reducers in H2SO4
- ACIDIC
- Few organisms larger than bacteria: nematodes, gnathostomulids
- This is good for marine archeologists
- Some are caused by ship basins, others are natural
- Some long-lasting, natural anaerobic areas: SANTA BARBARA BASIN
- Estimated that it has been stagnant for 1000+years
- Black sea, Fjords of Norway
- Nice up at surface, but deep down=YUCK
- Humans may cause it due to dredging etc
-
System can be overwhelmed with too much input
- DEAD ZONE off Louisiana
- Much input from Mississippi River
- Detritus, nutrients
- Fertilizers from farms etc
- Spring phytoplankton bloom, dead phyto. Sinks, stratificaion occurs
- No or poor mixing-everything just rots
- Then SEASONAL OVERTURN
- Due to storm that brings everything up
- Black stuff comes up, causes fish to jump out-"JUBILLE"
-
Too much sewage or effluent
- Primary treatment: screen for chunks
- Secondary: sewage settle and is treated with bleach/chlorine to decontaminate
- Sludge is dried and removed
- Chlorine must eventually be removed form sewage outfall
- Outfall-where water goes into ocean
- Interferes with nervous system of vertebrates if chlorine present
- Tertiary: fit to drink
-
Other organic
- Petroleum products: various fractions
- More refine=more toxic
- Some floats: evaporates
- Can be toxic to birdsm, plnakton etc
- Fumes cause disorientation
- Some sinks: coat sea floor, closes burrows, coats marine life, creates anoxic layer
- Other effects:
- disrupts respirations
- Prevents self cleaning by birds, seals etc
- Self cleaning=>fluffy=> warm
- Can't clean=> may freeze
- Block body effects
- Black tar covers barnacle etc
- Cooks them in own shell
- Slimy organisms slough off tar
- On sandy beach with debris such as Sargassum
- Forms foamy mix, "Chocolate mousse"
- Causes troubles in animals CNS
- Effects will depend on
- What temperature and where
- Salt marshes-majorly affected-no get out
- Inorganic pollutants
- Pesticides, bioaccumulation; PCBs heavy metals
-
Pesticides
- Can act on nervous system or prevent reproduction
- Problem: non targeted species may die
-
Bioaccumulation: DDT
- First of all, some humans majorly allergic
- Diatom: 1 dose DDT
- Copepod: 10 doses
- Fish 100 doses
- Large fish 1000 doses
- Bald eagle 10000
- Not eating DDT, getting it from its food
- DDT has half life of 15 years
-
PCB's
Accumulate in fat, disrupt enzymatic pathways
-
Heavy metals
- Disrupt enzymatic pathways, interurpt nervous transmission
- Some mollusks (oysters for ex) not affected
- Ie Lead/ mercury LAVAKA BAY in there and the organisms can live and you can't tell its saturated until you die after eating it
- Solutions?
- Contain it, re-use it, prohibit it
- Some pollutants persist for long times
- If buried, last even longer
-
Is something a pollutant?
- Bio-assays: expose test animal to various concentrations of new compound
- Sea urchin embryo is often used b/c similar to vertebrae then
- If causes problem for it, STOP
- If pass urchin, move on to shrimp, mice, monkeys etc
|
|