Human impact on environment Flashcards
what is climate?
Refers to the long-term pravalent weather conditions of an area
what is the atmosphere made up of
nitrogen
oxygen
trace gases
what is the function of greenhouse gases
they absorb long wave radiation emitted from the e earth and prevent it escaping into atmosphere
what happens if there is an increase in concentration of greenhouse gases
leads to the enhanced greenhouse effect
what 3 things happen because of global warming
increased concentration of CO2
increased methane concentration
increased temperatures
what causes an increase in CO2 concentration in atmosphere?
burning of fossil fuels
deforestation
what causes an increase in methane concentration
livestock
coal mining
expansion of rice agriculture and landfill
impact of increasing temperatures
more evaporation
rising sea levels
increased wildfires
loss of biodiversity
more droughts
what is the ozone
greenhouse gas found at low concentrations 15-50km above earths surface. Its function is to aborb UV rays from the sun.
causes of ozone depletion
caused by chemicals called CFCs released by refridgerators, aerosol, packaging.
impacts of ozone depletion
more skin cancer
eye damage
what is carbon footprint
measure of total amount of greenhouse gas emissions of an individual, defined population or company per year.
5 strategies to reduce carbon footprint
reuse/recycle drive less reduce need for heating reduce carbon emissions reduce energy needs
what are the 2 main things that influence the availability of water
destruction of wetlands
construction of dams
why is upping the price of water a clever strategy to reduce wastage
people are less likely to over use water if it is more expensive
expalin how poor farming practice leads to waste in water
fertilizers and pesticides
overgrazing
benefits of wetlands
improve quality increase availability of water improves irrigation water for irrigation purifies water
why are exotic plants viewed as bad
use large quantities of water
briefly explain eutrophication
agricultural water contains pesticides and herbicides which pollute natural river sources and cause excessive growth of algae in rivers. (algal bloom) it then depletes the O2 levels depleting the O2 for other species, they then die and cause the river to become highly toxic.
why is heated water less useful
heated water has a lower O2 content - difficult to support life.
why are alien plants problematic
blocks waterways
reduces light to other plants
what is food security
acess by all people at all times to adequate, safe and nutritios food for a healthy and productive life.
list 7 causes of food security
exponential growth of humans drouights and floods poor farming practice alien plants loss of wild varieties and it impacts gene pools genetically engineered food food wastage
what is biodiversity
variety of plant and animal species on Earth.
factors that reduce our biodiversity
- Habitat destruction
- poaching
- alien plant invasions
list 6 ways in which habitats can be destroyed
- farming methods
- golf estates
- mining
- urbanization
- deforestation
- loss of wetlands and grasslands
ways in which biodiveristy can be maintained
control alien plant invasions
suistainable use of the environment
how can one control alien plant invasions
mechanically removal
chemical removal
biological removal
what is solid waste
any solid material that is of no use to humans and which needs to be disposed of in a safe and environmentally friendly manner.
how is a landfill rehabilitated
covering the old landfill site with clay (impermeable to water) and then covered with topsoil and then vegetation
why are landfills toxic
contributes to soil and groundwater pollution ( rain seeping)
name of the toxic substance produced by a landfill
leachate
