section b

• define ecosystem

  a natural system made up of plant, animals and the environment
• what does complex interrelationship do

  link between non living and living components
• define biotic

  living features eg plants and animals
• define abiotic

  non living environmental factors eg climate, soil, water and temperature
• what are the 2 scales in ecosystems

  local small scale = pond, global scale = tropical rainforest
• define producers

  convert energy from the environment into sugars
• define consumers

  get energy from the sugars produced by the producers eg pond snail
• define decomposers

  break down plant and animal material and retain nutrients to the soil eg bacteria and fungi
• define food chain

  shows the direct links between producers and consumers in a simple line
• define food web

  shows all the connections between producers and consumers in a more complex way
• define nutrient cycle

  nutrients are foods that are used by plants or animals to grow. 2 sources: rainwater washes chemicals out of the atmosphere, weathered rock releases nutrients into the soil
• what are 2 impacts of change on a ecosystem

  thousands of years are required for an ecosystem to develop, balance is needed for it to remain sustainable
• what are changes that can take place at different scales

  global = climate change, local = change to a habitat
• what is an example of how change can effect a ecosystem

  avington park lane, winchester. a county estate close to winchester. the lake is historical and ecological importance. lack of maintenance = silt and vegetation growth. created an excellen habitat but the view had been lost of lake from the house. 2014 - restoration, view restored but new waterslide habitats to attract birds
• state 3 changes due to human activities

  woods cut down, destroying habitats and affecting the nutrient cycle and agricultural fertilisers can lead to eutrophication: nitrates increase growth of algae will deplete oxygen and fish may die and hedge rows removed to increase size of fields but habitats will be destroyed altering plant/animal balance
• how can natural changes effect ecosystems

  droughts can dry up in places this changes the edge of the pond environment. plants will dry out and die. fish starved of oxygen might not survive
• name the 8 characteristics of global ecosystems

  polar, tundra, tropical rainforest, desert, dedious and coniferous forests, temperate grassland, tropical grassland and mediterranean
• describe polar region

  cold air sinks at north and south, resulting in low temperatures and dry conditions. main polar regions are antarctica and greenland where temperatures go below -50
• describe tundra region

  low growing plants, retain heat and moisture in the cold

  eg northern canada and northern europe - reindeer have adapted to survive here
• describe tropical rainforest region

  high temperatures and heavy rainfall - ideal conditions for plants to grow. 6% of earths land surface
• describe desert region

  1/5 of earths land surface. sinking air stupid clouds from forming resulting in high daytime temperatures and low night time temperatures
• describe decidous and coniferous forests region

  decidous trees shed their leaves in winter and retain moisture

  coniferous trees are cone - bearing evergreens to maximise photosynthesis

  coniferous forests are in the north eg canada
• describe temperate grassland region

  vast areas of grassland in north america and eastern europe.

  warm, dry summers and cold winters. land is used for grazing animals
• describe tropical grassland region

  wet and dry season. dry season is very hot and wildfires can break out. violent thunderstorms can occur during the wet season. large herds of animals graze on these grasslands
• describe mediterranean region

  hot, dry and sunny summers with mild winters. due to pressure belts migrating north and south during the year. vegetation is fruit and olive trees, such as lemons and oranges.

  eg california usa, south africa and parts of australia
• where are tropical rainforest found

  broad belt through the tropics

  eg central and south america, south east asia and northern australia
• what is the rainforest climate like

  warm and wet conditions, found in equatorial zone - over 2000mm per year and 27 degrees average, temperature is high and constant, rainfall is high: rising air =clouds =heavy rain
• what are the soils like

  infertile, most nutrients found on surface = dead leaves decompose rapidly in hot humid conditions, trees have shallow roots = absorb nutrients, fungi transfer nutrients directly from air, heavy rainfall = washes away nutrients = leaching = leaves behind rich soil
• what plants and animals are in the rainforest

  supports largest number of species of any biome, 7% of worlds land mass = over half of all plants and animal species, has a huge biodiversity
• name 3 plant and animals found in TRFs

  birds live in canopy = feed on nectar, mammals like monkeys and sloths = well adapted, animals like deer and rodents live on the floor
• how do plants and animals adapt in the rainforest

  majority live in canopy - most light, forest floor = dark, small changes = knock on effect of entire ecosystem, biotic factors have a close relationship with abiotic factors
• name 2 plant/animals that have adapted in TRFs

  sloth and strangler figs
• what adaptions do sloths have

  camoflague, sharp teeth to defend themselves, nine cervical verterbrate to scan for threats, thick dense coats to keep them dry during rainy season
• what adaptations do strangler figs have

  fig sends aerial roots down trunk until they reach the ground. as it grows the fig will surround the host, criss cross its roots and start to strangle. the fig branches will grow taller to catch the sun and roots rob the host of nutrients. the host will die and leave a hollow sturdy trunk
• what is the purpose of camoflague

  allow it to blend in - protecting itself from predators and stalking prey
• example of camoflague

  green eyed tree frogs has flaps of textured skin around its body to look like tree bark
• what is the purpose of mimicry

  pretending to be something else
• example of mimicry

  non poisinous dart frog is brightly coloured to look like poisinous relative
• what is the purpose of limited diet

  eat foods that other birds and animals are unable to access
• example of limited diet

  toucan - strong beak can open fruits