1.5 Humans and Pollution Flashcards
Define pollution.
the addition of a substance or agent to an environment through human activity, at a rate greater than that at which it can be rendered harmless by the environment, and which has an appreciable effect on the organisms in the environment.
Distinguish between point and non-point source pollution.
point source: released from a single, identifiable source
non-point source: released from numerous, widely dispersed sources
Distinguish between persistent and biodegradable
- persistent: cannot be broken down by living organisms and so are passed along the foodchain
- biodegradable: not stored in biological matter or passed along food chains.
Distinguish between acute and chronic
acute: pollution that produces its effects through a short, intense exposure. symptoms are usually experienced within hours.
chronic: pollution that produces its effects through low level, long term exposure. disease symptoms develop up to several decades later.
Distinguish between primary and secondary pollutant
primary: active on emmission
secondary: formed by primary polluntants undergoing a physical or chemical change
what is DDT?
a synthetic pesticide that was used during the 1940s and 1950s to extensively control the lice that spread typhus and mosquitoes that spread malaria
Evaluate the effectiveness of Change the human activity that generates the pollutant in the first place (intervention)
PROs: - proactive becasue pollutant is not created in the first place
- reusing/recycling has reduced consumption of resources
CONs:
- alternative technologies are expensive to develop + may only work in certain enviornments i.e solar panels
- certain goods can only be recycled in certain conditions
- difficult to change behaviours
Evaluate the effectiveness of Minimize the amount of the pollutant released into the environment. (intervention)
PROS:
- more politically / socially acceptable than an outright ban
CONS:
- reactive
- tends to be expensive
- difficult to enforce and measure in unregulated parts of the economy (the informal sector)
Evaluate the effectiveness of Clean up the pollutant and the affected areas after the pollutant has been released (intervention)
PROS
- provides visible, short term results
- can help restore ecosystems and biodiversity
CONS
- labour intensive -> expensive (when people are involved)
- doesnt always reverse damage
- reactive
- sometimes scientifically impossible
advantages of DDT
- cheap (good for developing countries)
- helps fight against malaria, lupus (+ other insect caused diseases)
- easy to use
- useful for insect control in crop and lifestock production, homes and gardens (pesticides)
disadvantages of DDT
- toxic (effect of DDT on birds of prey in thinning their eggshells and reducing population numbers) → severe decline in bald eagle numbers
- persistent -> biomagnification (food chain) and bioaccumulation (organisms)
- POP
- some people exposed -> higher risk of cancer
- farmers -> increased risk of astham and/or diabetes
how do political systems affect the choice of pollution management strategies?
weak regulation and lack of enforcement in LEDC’s; strong coorporate involvement and lobbying in policy decisions in MEDC’s
how do economic systems affect the choice of pollution management strategies?
pollution can be promoted if the environment is seen as a free resources; the cost of reducing or cleaning pollution would reduce the likelihoods of solving the pollution problem
define Persistent Organic Pollutant
organic compounds that are resistant to environmental breakdown through biological, chemical or photolytic (i.e. broken by light) processes.
measuring pollution indirectly
record changes in biotic and abiotic factors
- e.g. recording the presence or absence of indicator species like dragonflys
measuring pollution directly
record the amount of pollution in air, water, soil
e.g. the acidity in rainwater
- altering human activites
- campaigns
- education
- community groups
- gov. legislation
- economic incentives/disincentives
- controlling the release of the pollutant
- legislating and regulating standards of emission
- developing / applying technologies for extracting pollutant from emissions
- clean up and restoration of damaged systems
- extracting and removing pollutant from ecosystem
- replanting/restocking lost or depleted populations and communities
define bioaccumulation
The build up of non biodegradable or slowly biodegradable chemicals in the body
define biomagnification
the process whereby the concentration of a chemical increase at each trophic level
different levels of pollution management
- altering human activity
- regulating and reducing quantities of pollutant released at the point of emission
- clean up and restoration
