B17 Flashcards
What is biodiversity ?
Variety of differnt species of organisms on earth , or within an ecosystem
Why is high biodiversity important?
It makes sure the ecosystems are stable because different species depend on each other for things like shelters and food. Different species can also help to maintain the right physical environment for each other.
Why is the population rising?
Medicines and farming methods , whcih have reduced the number of people dying from disease and hunger. Great for humans , but it has an effect on the world around us.
How has population growth effected the environment?
Pressure eon the environment as we need more resources to survive . More raw materials are used as people are demanding a higher standard of living. One day we will run out of raw materials
What has led to more waste?
Rapid growth of human population and an increase in the standard of living mean that increasingly more resources are used and more waste is produced unless waste and chemical materials are properly handled mor pollution will be caused
How can pollution occur?
- water
- air
- land
What is water pollution?
Sewage and toxic chemicals from industry can pollute lakes, rivers and oceans , effecting the plants and animals that rely on them fro survival(including humans). And the chemicals used on land (fertilisers , pesticides and herbicides) can be washed into water
What is land pollution?
We use toxic chemicals for farming (pesticides and herbicides) we also bury nuclear waste underground and dump lots of waste in landfill sites
What is air pollution?
Smoke and acid gases released intot he atmosphere cam pollute the air eg. Sulfur dioxide can cause acid rain.
Why pollution is a problem?
Kills plans and animals , reduces biodiversity
What is the temperature of the earth , how is it balanced?
Between energy it gets from the sun wnd the energy it radiates out into space.
What do gases in the atmosphere do?
Act as an insulating layer . They absorb most of the energy that would normally be radiated out into space , and reradiated it in all directions (including back to earth) . This causes temperatures to rise.
Why gases in the atmosphere are need?
There would be nothing to keep the enrgy in , making the world very cold
Why is the earth heating up?
Increasing levels of greenhouse gases. This is global warming, which is a type of climate change and causes other types of climate change
What are greenhouse gases?
Gases in the stmosphere thta keep nergy in. Main ones are carbon dioxide and methane
Consequences of globalw amring
- loss of habittas, when low lying areas are flooded
- changes in distribution of species , due to the temperature /rain fall
- changes in migration patterns , of birds , insects and mammals could change due to the changing temperature
- reduced biodiversity- due to the climate change many organisms will be unable to survive in The changing conditions and will be at risk of becoming extinct
What do humans use land for?
1) building,, quarrying , farming and dumping waste. So there is less land available for other organisms. Sometimes it requires deforestation or destruction of habitats like peat bogs.
What is deforestation?
Cutting down trees in forests. Causes big problems on a large scale
Why does deforestation take place?
- to clear land fro farming to provides food
- to grow crops from which biofuels based on ethanol can be priduced
How does burning trees reduce carbon dioxide taken in?
- cutting down trees measn amount of co2 removed from atmosphere during photosynthesis is reduced
- trees lock up some of the carbon that they absorb during photosynthesis in their wood, which can remove it from atmosphere for hundreds of years. Removing trees means that less is locked up
How deforestation leads to more carbon in the atmosphere?
- co2 is released when trees are burnt to clear land
- microorganisms feeding on dead wood released carbon dioxide as a waste product of respiration.
How does deforestation lead to less biodiversity?
-habitats like forests contain huge numbers of species of plants and animals , so when they are destroyed there is a danger of many species becoming extinct , biodiversity is reduced.
What are bog?
Areas of land that are acidic and waterlogged. Plants that live in bigs dont fully decay when, they due , because theres not enough oxygen. The partly rotted plants gradually build up to for, peat.
Forms of beat bog?
Carbon in the plants are stored in the peat instead of being released. Peat bogs are often drained so the area can be used as farmland , or peat is cut up and dried to use as fuel. Also sold for compost, peat is being used fast than it is formed.
How peat bogs being destroys add carbon to the atmosphere?
Destruction of peat bogs and other areas of peat to produce garden compost , reduces the area of this habitat and thus the variety of different plant , animal and microorganisms species that live there (biodiversity). Burning this releases carbon into the atmosphere
How can we maintain biodiversity?
- bredding programs for endangered species
- protection and regeneration of rare habitats
- reintroduction of field margins and hedgerows in agricultural areas where farmers grow only one type of crop
- reduction of deforestation and carbon dioxide emissions by some governments
- recycling resources rather than dumping waste in landfills
How are humans negatively effecting biodiversity?
- polltuion
- deforestation
- misuse of land
- global warming
