22- Humans and the environment Flashcards
how can food production be increased
1- using agriculture machinery
2- using agriculture chemicals (fertilizers, insecticides, herbicides)
3- selective breeding
examples of agriculture machinery
tractors- to cultivate larger area in shorter time
fertilizers
add more mineral ions (nitrate ions)
insecticides
sprayed on crop to kill insects that reduce yield or make it look less appealing
herbicides
sprayed to kill weeds, which compete with the crop plant to their growth
monoculture
growing crop plants of the same variety in a large area
negative impacts of monoculture
1- low biodiversity
2- only few species can live where crop is growing
3- increases the pest population on the crop
4- insecticides may kill harmless insects too
solutions to negative impact of monoculture
1- using mixed culture to decrease insect spread
2- using methods other than insecticides to control insects pests.
negative impacts of intensive livestock production
1- diseases may spread easily
2- increase risk of having bacteria resistant to antibiotics
3- the waste can pollute the area nearby
why do some parts of the world not have enough food
1- unequal distribution of food in the planet
2- high food prices that some people cant afford
3- famine can happen due to natural disasters or wars or diseases.
reasons for habitat destruction
1- increased area for human benefits (crop, roads, house)
2- mining for natural resources
3- marine pollution that kills aquatic organisms
deforestation
cutting down of large number of trees
effects of deforestation
1- extinction of some species 2- flooding due to soil erosion 3- climate change, as reduces rainfalls 4- increase CO2 in the air, causing global warming 5- local people loose their homes
dangers of non-biodegradable plastics
1- turtles mistake it for jellyfish and eat it
2- it traps animals and may kill them
female contraceptive hormones
- hormones excreted in urine then becomes sewage
- they can effect fish by preventing their male hormone (testosterone) from working
- makes fish produce less sperms or change to female
nuclear fallout
accidents releasing radioactive substances into the air
effects of exposure to radioactive substances
- radiation sickness and burns
- DNA mutation, lead to cancer
why does exposure to radioactive substances effect us
ionizing radiation damages DNA
alpha
the most ionizing radiation, causing most damage if penetrates the body
pesticides
chemicals use to kill organisms that damage crop
insecticides, fungicides…), and to control transmit disease (mosquitoes
cause if water pollution
discharge of chemical waste into water
DDT
a pesticide to kill insects, but doesnt break down and remains in them and the soil, where other animals eat those insects and get harmed
cause of acid rain
sulfur dioxides and nitrogen oxides from burning fossil fuels dissolve in water making carbonic acid which turns into acid rain
effects of acid rain
1- damage and kill plants
2- seeps to soil and washes out ions
3- kill aquatic animals
4- damage vehicles and buildings (limestone)
solution for acid rain
1- cut down emission of sulfur dioxides and nitrogen oxides
2- use renewable energy
3- use catalytic converter in cars
greenhouse effect
CO2 trapping some of the infrared radiations transmitted from the sun to keep the earth warm
enhanced greenhouse effect
trapping more infrared radiations due to the increase of CO2 in the air, causing global warming
sustainable resources
resources which can be removed from the environment without running out (wood for fuel)
sustainable development
providing for the needs of an increasing human population without harming the environment
recycling glass
- crushing used glass
- melting it at high temperature
- use to make new glass objects
advantages of recycling glass
- releases less CO2 than making glass
- reduces the use of raw materials
recycling paper
- mix waste paper with water and chemicals to form pulp
- filter to remove any glue
- spread into sheets to make new paper
advantages of recycling paper
- causes less water and land pollution
- uses less energy
advantages of recycling plastic
- reduce amount of fossil fuels used
- makes fleece clothing and packaging
advantages of recycling metal
- uses less energy from fossil fuels than mining to get the ore of a metal
- less mining to less habitats damaged
reasons for conservation
1- prevent extinction 2- not harm the environment 3- increase number of plants for medicines 4- destructing food chains 5- increase biodiversity
conserving forests
1- reduce cutting down trees
2- plant new trees to replace old ones
3- educate people about the importance of conserving trees
conserving fish stock
1- reducing the number of fish caught
2- specify fishing amounts for different species
3- breed large number of fish in fish hatchers then release them
conserving endangered species
1- captive breeding
2- protecting their natural habitat
3- reduce hunting
4- start conservation program
reason species become endangered
- habitat destruction
- hunting
- pollution
- introducing of new species
effect of sewage
1- increase water pollution, eutrophication
2- causes diseases as it contains bacteria
treatment of sewage
1- trickling filter
2- activated sludge
