environmental challenges 1 Flashcards
environmental studies
study of relationship between humans and environment
interdisciplinary approach of environmental studies
ecology…geography…sociology…resource management..economics…policy, law, ethics…
collapse
when human systems:
- consume more resources than the environment can provide
-make the environment toxic
-fail to adapt to changing environmental conditions
*human systems can and do collapse
(lessons from the past) Easter Island (Rapa Nui)
- civilization developed over time which caused deforestation
- failed to notice environmental warning
- disparity between classes widened
-exceeded CARRYING CAPACITY and collapsed
where do we stand today? have we learned from historical lessons?
-population growth (spurt around late 1900s)
- unsustainable economic growth and consumption
- loss of biodiversity
- decline of vital life-support ecosystems
- GDP (monetary value) increasing since 1900s
indicators of loss of biodiversity and decline of vital life-support
declining fish stocks
degradation of forests
global warming
degraded air quality
depleted/ degraded fresh water supplies
degraded agricultural soils
contemporary human stressors on the environment
similar to easter island:
population growth
consumption of resources
production of wastes
additional stressors:
alteration of global-scale biophysical processes (climate change rising)
alien chemicals and organisms in env
alien chemicals
many environmental impacts
manmade
don’t break down naturally
alien organisms
does not naturally occur in the area and has been brought in accidentally or intentionally by man
invasive species
ex. purple loosestrife, emerald ash borer bugs
2 categories of modern global environmental change
systemic - human modification to a global-scale system
cumulative- similar change in multiple places that add up to a global impact
types of systemic change
atmospheric systems
ocean circulation (it is not still, hot rises and cool falls, convection)
types of cumulative change
deforestation
biodiversity loss
desertification
land degredation
reductions in freshwater quality and availability
complexity key premise
the Earth functions as a set of complex, interconnected systems
changes in one system can cause changes in others
(some places like Vancouver are very complex even though it’s small)
carrying capacity
number of individuals of a species that can be supported by the resources in an area of land, indefinitely
overshoot carrying capacity = impact
system is altered, damaged or DELPLETED and eventually population declines
