2Contents Adaptation: Camel and Polar Bear Competition: Plants & AnimalsImpact of HumansHuman Population GrowthUrbanisation & IndustrialisationEffect of FertilisersEffect of PesticidesFishing & ForestryPollutionGlobal WarmingEnergy TransferCarbon & Carbon CycleNitrogen Cycle
3Adaptation 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
4Adaptation 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
5CompetitionOrganisms compete with each other for certain essential needs for survival. Survival of the Fittest!Plants compete for:- light for photosynthesis- water- nutrients & mineralsAnimals compete for:- food- mates to reproduce- living space
6Impact of HumansHumans pose a huge threat to lives of animals, plants and their environmentOur impact is so great due to:- technologies that change the world so quickly- population increase- consumption of natural resources, and waste
7Human Population Growth Humans can adapt to survive in almost all habitats and climates. The human population is increasing rapidly and is threatening the environmentThe population will eventually be limited by these factors:- food and water supply- disease and pollution- over-crowding- sudden changes in climate
8Urbanisation & 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 areasDevelopment of industries. The effects:- non-renewable fossil fuels are used for energy- release of greenhouse gases speeds up global warming
9Effect of Fertilisers Intensive farming can damage the environment. Fertilisers containing plant nutrients are sprayed onto fieldsPlants 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 sunlightPlants begin to die providing food for microbesMicrobes increase the competition for oxygenWater becomes de-oxygenated causing aquatic life to die
10Effect of PesticidesPesticides used to kill insects and other crop damaging micro-organisms can effect the food chainPesticides can be abosrbed by small aquatic animalsFish each the animals, which have eaten pesticideBirds eat the fish
11Fishing & Forestry Fishing: Unsustainability: the using up of resources faster than they are produced so that they will not continue in the futuree.g. North Sea Cod are over-fished so are reproducing slower than are being caught. Effect population is heavily decliningForestry:Humans burn wood or clear land for farming deforestation:1) destroys habitats2) causes soil erosion barren land and flooding3) causes pollution from combustion4) increased levels of carbon dioxide as loss of photosynthesis
12PollutionAtmospheric: Caused by combustion, exhaust fumes, livestock, waste dumpsEffects:- 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 animalsWater: Caused by deposition of substances into seas, lakes, rivers- sewage and oil, which destroy habitats and kill animals- fertilisers and pesticides, which damage ecosystems
13Global WarmingThe Earth is heating up as CO2 levels are increasing – why?Earth’s atmosphere is an insulating layerIt lets the Sun’s heat in but also stops some going outIncrease in carbon dioxide due to:1) Deforestation (loss in photosynthesis)2) Combustion of fossil fuelsIncrease in methane due to:1) livestock farming2) rotting plant material3) drilling for oil and gas
14Energy TransferIn 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 rapidly1st: photosynthesis2nd onwards: respirationexcretionmovementtransport
15Carbon & Carbon Cycle Living organisms need carbon to: make food (green plants photosynthesise)make energy (through respiration)make new cells for growth and repairCarbon cycles through ecosystems, moving repeatedly from one organism to another, and between organisms and the environment.
16Nitrogen CycleLiving 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.
17Summary Organisms adapt to suit their environment Plants and animals compete for certain things to surviveHumans impact on the environment and the lives of othersHabitats and the environment are destroyed by urbanisation & industrialisation, use of fertilisers, use of pesticides, fishing & forestry, pollutionGlobal warming is increasing rapidly due to human impactEnergy is transferred through food web trophic levelsCarbon is a necessity to life, and is transferred through the carbon cycleNitrogen is a necessity to life, and is transferred through the nitrogen cycle