Lecture 11 Flashcards
1
Q
Post wwll population boom
A
- Unknown that more P was getting into water as a result
- Increased organic pollution
- Water bodies become increasingly eutrophic with poor water quality
2
Q
1960’s -1980’s
A
- Efforts to improve water quality was gradual
- It was controversial if phosphorus or carbon had the greater role in eutrophication
3
Q
1969-1973 experiments
A
- Team P: OCED study looking at P levels in 107 lakes
- Team C: Algal bioassays (supported by soap companies who often used P in products)
4
Q
1974 P experiment
A
- Took lowest C lake and added only P and N
- Also took a two basin lake, divided in half, added C,N and P in one side and only C, N in another
- REsult that P wasmajor case of eutrophication
5
Q
1972-2012
A
- Attempts to limit phosphorus inputs to water
- treating and diverting waste water
- Bans on phosphorus products (which were slow)
6
Q
Impacts of eutrophication
A
- Taxic cyanobacteria abundence
- Low O2 levels
- Low biodiversity
7
Q
Nitrogen
A
- Originally harvested to use in fertiliser
- Humans have altered global N cycles so much that industrial N is raining down on us
- N pollution caused by fertiliser run-off
8
Q
Hypoxia dead zones
A
- Caused by excess nitrogen
- Gulf of mexico dead zones covered 6000 every summer
9
Q
Sources of microplastics
A
- (<5mm)
- Primary microplastics: microbeads (e.g.cosmetics), banned in Uk since 2017
- Secondary microplastics: broken down larger plastic objects
- Other sources: washing synthetic fabric, tyre wear and tear
10
Q
Microplastic impacts
A
- Impair cognition in hermit crabs
- Lower filtration/growth rates in bivalves
