Environmental Change

Changes in the Environment- caused by various factors such a lack of food source- may affect the distribution and behaviour of organisms.

Animals and plants are exposed to environmental change- Living (change in predator, food source, competitor) Non-living (Change in temp/rainfall) 

Effects on enviromental change

• Changes in the enviroment affect the distribution and behaviour of living organisms. (e.g. humans cutting down trees.
• This deforestation can have local effects, such as reduction in food and less shelter for the animals
• Could change amount of rainfall and temperature
• Also could change the distribution of bird species

Predators and Prey

• If they prey population grow, predator numbers will repsond to the increases food supply by increasing as well
• Growing predator numbers will eventually reduce the prey supply and the predator population will also decrease

Air pollution 

The most common source of air pollution is the combustion of fossil fuels. This usually happens in vehicle engines and power stations. Sulpher dioxide is released if the fuel contains sulpher dioxide. This gas contributes to acid rain.

Lichens can be used as air pollution indicators. Especially the concentration of sulfur dioxide in the atmostphere.

Lichens are plants that gorw in exposed places such as rock or tree bark. They need to be very good at absorbing water and nutrients to grow there. Rainwater contains enough nutrients to keep them alive. Sulfur dioxide can damage lichens preventing them from growing. This makes lichens natural indicators for air pollution. 

• Bushy Lichens need really clean air
• Leafy lichens can survive a small amount of air pollution
• Crusty lichens can survive in more polluted air

In a place where no lichens are growing, it is often a sign that the air is heavily polluted with sulfur dioxide

Water Pollution 

Water pollution is caused by the discharge of harmful substances into rivers, lakes and seas. Many aquatic invertebrate animals cannot survive in pollued water so their presence or absence indicates the extend to which a body of water is polluted.

• Clean - Mayfly larva
• Low- Freshwater shrimp 
• High- Water louse
• Very High- Rat tailed maggot, sludgeworm 

Scientists can use equipment to measure environmental changes. E.g Oxygen levels in water can be measured using oxygen probes. There are often connected to a data logger.

Rainfall 

Rainfall is measured using a rain gauge. The depth of rain is usually measured daily e.g. at the same time every morning.

Temperature

A thermometer can be used to measure the temperature in an environment. 

A digital themometer connected to a data logger allow an almost continuous measurement of temperature over time. It also has the advantage that no one needs to be there to take a reading.

Scientists can use equipment to measure environmental changes. E.g Oxygen levels in water can be measured using oxygen probes. There are often connected to a data logger.

Rainfall 

Rainfall is measured using a rain gauge. The depth of rain is usually measured daily e.g. at the same time every morning.

Temperature

A thermometer can be used to measure the temperature in an environment. 

A digital themometer connected to a data logger allow an almost continuous measurement of temperature over time. It also has the advantage that no one needs to be there to take a reading.

Scientists can use equipment to measure environmental changes. E.g Oxygen levels in water can be measured using oxygen probes. There are often connected to a data logger.

Rainfall 

Rainfall is measured using a rain gauge. The depth of rain is usually measured daily e.g. at the same time every morning.

Temperature

A thermometer can be used to measure the temperature in an environment. 

A digital themometer connected to a data logger allow an almost continuous measurement of temperature over time. It also has the advantage that no one needs to be there to take a reading.