what resources do plants and animals need to survive?
- food and water
why do living things need to compete for resources?
- there is not enough for every plant or animal to get what it needs
what happens to organisms that are not successfull at competing?
- they die because they do not get what they need
causes of enviromental change
- burnt in car engines-lead to global warming and it causes polar ice caps to melt, sea levels rise and this will cause flooding
Factories and power stations
- sulphur dioxide and nitrogen oxide is given off, this leads to acid rain which can erode sculptures,rocks, plants and animals in water bodies die
Landfills, waste, mining and quarrying
- can get oil spillage
measuring enviromental change
Thermometers measure highest and lowest temperatures reached within a 24 hour period
pH meter: measures how acidic or alkaline the water is
Rain gauges: are for measuring rainfall. the depth of water collected indicates how much rainfall has fallen
Oxygen meters: measures the concentration of dissolved oxygen in the water.Unpolluted water contains lots of dissolved oxygen
Lichens as indicators of air pollution
Lichens are plant-like organisms that are found on crusty patches of rock, tree trunk and walls. Lichens absorb water and minerals form rainfall and directly from the atmosphere,over their entire surface area.
Lichens are used as bio indicators of sulphur dioxide pollution because they are sensitive to sulpur dioxide pollution form burning fossil fuels. Different lichens tolerate different levels of sulphur dioxide in the air. Therefore, the presence or absence of a particular typeof lichen can tell us the level of sulphur dioxide in the air.
The more polluted the air, the fewer lichen species there are.the cleaner the air is,the more lichen species there are.