Living Things in their Environment

1. Living Things in their Environment

2. Contents • Adaptation: Camel and Polar Bear • Competition: Plants & Animals • Impact of Humans • Human Population Growth • Urbanisation & Industrialisation • Effect of Fertilisers • Effect of Pesticides • Fishing & Forestry • Pollution • Global Warming • Energy Transfer • Carbon & Carbon Cycle • Nitrogen Cycle

3. Adaptation • Camel well suited for desert: - slit-like nostrils, two rows of eyelashes to keep sand out - wide, flat feet to stop them sinking into sand - thick fur to keep sun off their skin

4. Adaptation • Polar Bear well suited for Arctic: - black skin absorbs heat well - white fur camouflages against snow and ice - thick layers of fat and fur for insulation - wide, hairy soles avoid bear from slipping

5. Competition • Organisms compete with each other for certain essential needs for survival. Survival of the Fittest! • Plants compete for: - light for photosynthesis - water - nutrients & minerals • Animals compete for: - food - water - mates to reproduce - living space

6. Impact of Humans • Humans pose a huge threat to lives of animals, plants and their environment • Our impact is so great due to: - technologies that change the world so quickly - population increase - consumption of natural resources, and waste

7. Human Population Growth • Humans can adapt to survive in almost all habitats and climates. The human population is increasing rapidly and is threatening the environment • The population will eventually be limited by these factors: - food and water supply - disease and pollution - over-crowding - sudden changes in climate

8. Urbanisation & Industrialisation • More and more people are moving into the cities. The effects: - increased pollution due to traffic, energy consumption and waste production - farmland is built on, land taken out of food production - loss of natural habitats, as cities and roads are built - rural communities and cultures dissolve as people leave to live in urban areas • Development of industries. The effects: - non-renewable fossil fuels are used for energy - release of greenhouse gases speeds up global warming

9. Effect of Fertilisers • Intensive farming can damage the environment. • Fertilisers containing plant nutrients are sprayed onto fields • Plants grow faster and boost crop yields. • Rain means may wash nutrients from the fields and into rivers and lakes (this is called run-off). • Eutrophication (hyper-nutirtion from fertisiler pollution) occurs which can kill almost everything living. • Algae grows fast using up lots of oxygen and blocking sunlight • Plants begin to die providing food for microbes • Microbes increase the competition for oxygen • Water becomes de-oxygenated causing aquatic life to die

10. Effect of Pesticides • Pesticides used to kill insects and other crop damaging micro-organisms can effect the food chain • Pesticides can be abosrbed by small aquatic animals • Fish each the animals, which have eaten pesticide • Birds eat the fish

11. Fishing & Forestry • Fishing: Unsustainability: the using up of resources faster than they are produced so that they will not continue in the future e.g. North Sea Cod are over-fished so are reproducing slower than are being caught. Effect  population is heavily declining • Forestry: Humans burn wood or clear land for farming  deforestation: 1) destroys habitats 2) causes soil erosion  barren land and flooding 3) causes pollution from combustion 4) increased levels of carbon dioxide as loss of photosynthesis

12. Pollution • Atmospheric: Caused by combustion, exhaust fumes, livestock, waste dumps • Effects: - smoke, which damages air quality - carbon dioxide and Methane, which cause climate change - sulphur dioxide and nitrogen dioxide, which mix with rainwater to form acid rain - carbon monoxide, which is poisonous to humans and animals • Water: Caused by deposition of substances into seas, lakes, rivers • Effects: - sewage and oil, which destroy habitats and kill animals - fertilisers and pesticides, which damage ecosystems

13. Global Warming • The Earth is heating up as CO2 levels are increasing – why? • Earth’s atmosphere is an insulating layer • It lets the Sun’s heat in but also stops some going out • Increase in carbon dioxide due to: 1) Deforestation (loss in photosynthesis) 2) Combustion of fossil fuels • Increase in methane due to: 1) livestock farming 2) rotting plant material 3) drilling for oil and gas

14. Energy Transfer • In every ecosystem, energy is transferred along food chains from one trophic level to the next. Energy is absorbed up a food chain, but at each trophic level, this amount of energy decreases rapidly 1st: photosynthesis 2nd onwards: respiration excretion movement transport

15. Carbon & Carbon Cycle Living organisms need carbon to: • make food (green plants photosynthesise) • make energy (through respiration) • make new cells for growth and repair Carbon cycles through ecosystems, moving repeatedly from one organism to another, and between organisms and the environment.

16. Nitrogen Cycle Living organisms need nitrogen to make proteins. They cannot get it directly from the air because nitrogen gas is too stable to react inside an organism to make new compounds. Nitrogen must be changed into a more reactive form to allow plants and animals to use it. Plants can take up and use nitrogen when it is in the form of nitrates or ammonium salts. Nitrogen fixation is the process when it is changed into a more reactive substance.

17. Summary • Organisms adapt to suit their environment • Plants and animals compete for certain things to survive • Humans impact on the environment and the lives of others • Habitats and the environment are destroyed by urbanisation & industrialisation, use of fertilisers, use of pesticides, fishing & forestry, pollution • Global warming is increasing rapidly due to human impact • Energy is transferred through food web trophic levels • Carbon is a necessity to life, and is transferred through the carbon cycle • Nitrogen is a necessity to life, and is transferred through the nitrogen cycle