4.4 Flashcards
bioaccumulation vs biomagnification
hot water
decrease DO
loss biodiversity
Increase toxin
reproductive systems
increase metabolic rate
migration
biological pollutants (invasive species)
hypoxia
hyperoxia
anoxia
hypoxia (deficiency of O2)
hyperoxia (opposite hypoxia)
anoxia (absent of O2)
extensive hypoxia and anoxia
minimal hypoxia and anoxia
phytoplankton bloom
decomposition
warm water stimulates decomposition
what is BOD
a measure of the amount of dissolved oxygen used by organisms present in water sample
a measure of the amount of dissolved oxygen required to break down the organic material in a given volume of water through aerobic biological activity
provide indirect measure
the demand for oxygen increases proportionally with the number of bacteria (respiration)
unpolluted water have bod 5mg/L or less
Indicator species
definition:
Organisms that show something about their environment by their abundance or scarcity
-sensitive to specific environmental conditions (bcs they have limited tolerance)
-Lichens (not a vascular bundle) takde wax so dia akan absorbs everything yang kena dia
for example for the freshwater ecosystem:
frogs and toads (have permeable skin and are affected by water pollutants)
mayfly larva (clean water)
sludge worms (very polluted water)
How lichen be used for biotic index?
what is the characteristic that make it suitable for biotic index?
sample lichen may be analysed to see contamination of heavy metal
susceptible to air-borne pollutants
air pollutants dissolved in rainwater and damage lichen
trent biotic index
1-10 scale (10 is the cleanest)
compare 2 ecosystems or point source pollutants and compare using Simpson’s diversity index
measure the effect of pollutant, not the pollutant
kick sampling
to collect macroinvertebrates in shallow water
eutrophication
bad effect:
water quality degradation
affect the fishing
miss recreational opportunity
Reduce, altering human activities
plant buffer zone
prevent leaching into seware
don tplough up frass
use stee slopes for pemn
regulating, regulate release of pollutant
treat wastewater to remove phsophateas and nitraes
divert and treat sewage
minimize fertilizer usage
educate farmers about effective timing of fertilization-avoid heavy rains
public campaign such as australia ( use zer o to low phosphorus detergent
waash only full loads
wash vechicle on
reduce lawn fertilization
compost faredena and food waste
collect pet feaces
removing, restoration, clean up
treat wastewater to remove phosphates and nitrates
precipitation (treatment with solution to percipitate phosphorus)
removal of nutrient enriched sediment e.g. mud pumping
removal of biomass (harvesting of common reed) and using it for thatching or fuel.
what are the sources of freshwater and marine pollution?
- Industrial waste
- sewage and wastewater
- accidental oil leakage
- mining activities
what are the types of aquatic pollutants?
- suspended matter (doesnt dissolve in water)
- toxic metals
- fertilizer
what are the parameters use directly to test the quality of aquatic systems?
- pH
- temperature
- turbidity
- nitrates/phosphates
what is direct measurement?
monitoring the level of pollutant
example:
1. temperature
2. nitrates/phosphates
what is indirect measurement?
what is indicator species?
monitor the effects of the pollutants on other factors
example:
1. BOD
2. DO
3. Indicator species
Indicator species is organisms that are used to assess the quality of an environment or indicate the presence of specific environmental conditions, including pollution
hypoxia vs anoxia condition
hypoxia (less oxygen)
anoxia (no oxygen)
what is eutrophication?
what are the stages?
Definition: natural or artificial addition of nutrients such as phosphates and nitrates to a body of water resulting in depletion of the oxygen.
- Excess nutrient such as phosphates and nitrates enter the water.
- Algae grows rapidly.
- Causes algal bloom on the surface of water
- Reduces sunlight to reach the bottom of water.
- Causes plant underneath to die
- oxygen level drop
- Bacteria uses oxygen thorugh areobic respiration for decomposition
- Low oxygen causes other organisms to die
- causes oxygen depletion.
what is BOD?
what do high and low BOD indicate?
BOD range in ppm for good/bad water quality?
a measure of the amount of dissolved oxygen required to break down the organic material in a given volume of water through aerobic biological activity
high BOD
1. Many organisms using oxygen for respiration
2. Low DO level (high pollutant levels especially nitrates & phosphates)
Low BOD
1. Few organisms using oxygen for respiration
2. High DO level (low pollutant level)
BOD level (in ppm)
1-2 - very good
6-9 -somewhat polluted
100 or greater - very polluted
examples of indicator species and their pollution level
Mayfly nymph (Low pollution)
Freshwater shrimp (slight pollution)
Worm a.k.a Tubifex (high pollution)
No life (extreme)
what is biotic index?
what
A scale 1(excellent) to 10(very poor)
causes of eutrophication
- Agricultural fertilisers run-off
- Industrial effluent
- Soil erosion (soil contains residues of manure and fertilisers)
what are the impacts of eutrophication?
- Increase in turbidity
- Decrese in DO
- Loss of fish species diversity
what is dead zone?
example of case study?
what are the causes of the case study location?
any international conflict?
areas in oceans of fresh water where there is not enough oxygen to support life
Example: Gulf of Mexico
Nutrient run-off from agricultural states of the western USA carries by the Mississippi River.
International conflict between countries (USA, Mexico and Cuba) as the gulf is shared.
What is aquaculture?
3 negative impact of aquaculture?
Farming, breeding, rearing and harvesting of plants and animals in all types of water environments such as ponds and lakes.
negative impacts:
- pollution
- antibiotic
- feed waste (eutrophication)
- GMO fish (outcompete native species) - habitat destruction
- mangrove ecosystem being converted into shrimp farming - spread of disease
positive impacts:
- reduce fishing pressure
- overfished species can replenish - consistenr food suply
- reduce the need for overfishing to meet customer demand
State 2 factors that are used to determine the conservation status of a species?
- population size
- reproductive behavior
- habitat quality
identify two strategies for fisheries management that could improve the conservation status of sea turtles.
- restrict the use of fishing nets
- implement laws against poaching
- replace wild fisheries with aquaculture
Describe two strategies for the management of sustainable capture fisheries.
- regulation of fishing quotas
- designation of marine protected areas
state one disadvantage of using a biotic index compared to measuring the pollutants directly.
- does not identify pollutant causing impacts
- does not help identify source responsible for impacts
