Nutrient Pollution Flashcards
What are the two modes of uptake of nutrients into the food web?
bacteria, algae and vascular plants
What are the two classes of nutrients and examples of each?
Macro-N, P, C and Si
Micro-Mg, Fe, Zn and Cu
What is the nutrient that causes the most primary production?
Phosphorous
What are the three trophic lake statuses and what do they mean?
Ogliotrophic- <10 ug P/L
Mesotrophic- 10-30 ug P/L
Eutrophic- >30 ug P/L
What two nutrients are greater than the biological supply and why?
Nitrogen-atmospheric form is not usable
Phosphorous-not found in atmosphere and less mobile and precipitates out of solution
Why is phosphorous causing primary production?
binds with cations (Al, Fe, Ca and clay), forms insoluble products and precipitates under oxic conditions
What is the preferred form of nitrogen for organism take up and in what pH is it found?
NH4+, neutral to acidic pH, if the water is alkaline it is converted to NH4OH which is very toxic to fish and other organisms
What are the two classifications of unnatural sources of pollutants and examples of each
Point-Source: sewage/industrial discharge and urbana storm water
Non-point: agricultural and urban run off, atmospheric deposition
How does agriculture lead to increased nutrient pollution?
excess phosphorous found in fertilizer can accumulate in soils and then the run off goes to water and causes cultural eutrophication
What are the impacts of cultural eutrophication?
anoxia, fish kills, loss of water quailty, loss of recreational habitat and toxins
How cultural eutrophication cause fish kills?
hypolimnion (low oxygen area of lake with colder temperatures) become anoxic because the algae takes all hte O2 on surface and as it decays it sinks to the bottom, thus killing fish
What are cyanotoxins?
hepatotoxins or neurotoxins produced by microcystsis, anabaena and aphanizomenon that are present in algal blooms
What are red tides?
caused by bloom of dinoflagellates in tropical and subtropical estuaries from nitrogen run off and produced by alexandrium and gymnodinium genera
What is the toxin found in these red tides and what does it cause?
Saxitoxin, causes paralytic shellfish poisoning, eventually leading to muscular paralysis and respiratory difficulty, increased prevalence world wide
What causes amensic shellfish poisoning?
pseudo-nitzchia spp. produces domoic acid which concentrate in shellfish and can result in memory loss and potential death in humans, found along pacific coastline
