living world

• what is an ecosystem

  a community of living organisms interacting with the non living ( abiotic) in their environment
• decomposer


  organism that eat both plant ( producer) and animal 9 consumer) matter to gain energy
• herbivore


  organisms that eat plant matter ( producers) to gain energy
• omnivore


  organisms that eat both plant ( producer ) and animal ( consumer) matter to gain energy
• consumers


  organisms that get their energy by eating other organisms
• carnivore


  organisms that eat meat to gain energy
• food chain


  a line of linkages between producers and consumers
• producer


  organisms that get their energy from the sun
• food web


  series of inter connected food chains which shows the flow of energy and nutrients between organisms at different trophic level
• nutrient cycle


  nutrients are used by plants and animals to grow, There are 2 main sources of- rainwater washes chemicals our o the atmosphere and weathered rock releases nutrients into the soil. When plants or animals die the decomposers help to recycle the nutrients making them available once again for the growth of plants or animals
• some ecosystems are on a small scale , what are they known as and list examples

  biomes

  - sahara desert, amazon tropical rainforest
• ecosystems can be small scale , eg..

  a pond, a meadow and a woodland
• biotic factors


  plants, animals and microorganisms and they can be divided into producers, consumers and decomposers
• abiotic factors


  non living : water, temperature, reliefs, soil type, fire, rocks, nutrients
• what is a biomass


  weight of living organisms, plants, animals, microorganisms
• what is humus


  dark, organic material that forms in soil when plant animal matter decay
• what do the circles in a gersmehl diagram show

  the relative sizes
• what do the arrows in a gersmehl diagram represent

  - shows movement of nutrients between the stores
• example of a small scale uk ecosystem : name

  epping forest
• epping forest

  - what is it an area of , what broad leaf trees are there

  - where is it located

  - most of the forest is a ? and many of the ??? are protected by ?

  - it is a xxx scale ? and a ? place where life cycle of xxx are linked to each other to form ?

  epping forest is an area of temperate deciduous ( lose their leaves in the autumn) woodland with broad leaf trees such as oak, beech and elm, in south east england. Most of the forest is a site of special scientific interest and many of the insects and fungi are protected by law. Epping forest is a small scale ecosystem and a natural place where the life cycles of plants, animals and other organisms are linked to each other and to the non living parts of the environment to form a natural system
• epping forest part 2

  . It depends on the energy flows and nutrient cycling, All ecosystems can be divided into the living or biotic components which comprises all organisms: plants, animals, bacteria and fungi, and the physical, non living or abiotic components. which include temp, water, light, wind and nutrients in the soil. The soil beneath the forest is a fertile brown earth. The nutrient cycle plays an important role in the forest. In the autumn , the leaves fa;l from the trees. and decompose, giving the soil its nutrients. Earthworms in the soil help top mix the nutrients and blend the layers within the soil. the tree roots are deep so help to break up the rock below. This helps give the soil more minerals., The trees take up the nutrients in the soil as hey grow in the summer. However, more nutrients are put pack in the soil when the autumn comes
• what is the impact of one changing component on the ecosystem

  if deer were fenced out of the epping forest , small plants and ash and birch seedlings would start to appear. ash seedlings grow faster than oak seedlings. As the ash trees grow, ash leaf litter would begin to build up on the woodland floor. Ash leaf litter is better food for earthworms than oak leaf litter so the number of earthworms would increase

  earthworms make up more than half the diet of badgers so these changes would increase the number of badgers in the area because there are more worms for them to eat
• biomes around the world ( distance from equator )


  learn diagram on showbie
• tropical rainforest - location and characteristics

  close to the equator

  - high temperatures and heavy rainfall associated with equatorial low pressure belt creates ideal conditions for plants to grow. Rainforests cover 6% of the earth's land surface. More than half the world's species of plants and animals live in this global ecosystem. a quarter of all medicines come from the rainforests plants
• desert - location and characteristics


  roughly 30 degrees north and south of equator

  - deserts cover 1/5 of the world's land surface. Hot deserts are associated with sub tropical high pressure belts. Sinking air stops clouds from forming, resulting in high daytime pressures, low night time temperatures, and low rainfall. plants and animals have trouble be well adapted to survive in these conditions
• polar location and characteristics

  - arctic and antarctic

  - cold air sinks at the north and south poles. resulting in very low temperatures and dry conditions . The main polar regions are antarctica and greenland where temps can fall below -50 degree celsius
• deciduous and coniferous forests - location and characteristics

  - roughly 50-60 degree north of equator

  - deciduous trees shed their leaves in winter to retain moisture. coniferous trees are cone bearing evergreens, retaining their leaves to maximise photosynthesis during the brief summer months . The UK's natural vegetation is deciduous forest. Further north, eg in canada and Scandinavia, coniferous forests dominate as they are better suited to colder climates
• temperate grassland - location and characteristics

  - roughly 30-40 degree north and south of equator ,inland away from coasts with hot summers and cold winters

  - this includes the vast areas of greenland in north america and eastern europe. These areas experience warm, dry summers and cold winters. Grasses can tolerate these conditions and this land is mainly used for grazing animals
• mediterranean - location and characteristics

  40-45 degree north of eqator also in isolated locations like south of equatior - south africa and western australia

  - countries around the mediterranean enjoy hot, sunny and dry summers, with mild winters. This is due to the pressure belts migrating slightly north and south during the year. Mediterranean vegetation includes olive trees and fruit trees, such as lemons and oranges. Other parts of the world have a similar climate eg california ( USA), south africa and parts of australia
• tropical grass land ( savanna) - location and characteristics

  between 15-30 degree north and south of the equator

  - the tropical climate in these lows latitudes is characterised by distinct wet and dry seasons. The dry season can be very hot and wildfires can break out. Violent thunderstorms can occur during the wet season. Large herds of animals graze on these grasslands, along with predators such as lions and leopards
• tundra - location and characteristics

  from the arctic circle to about 60-70 north ( eg canada, northern europe). there are only very small areas of tundra in the southern hemisphere due to lack of land at these latitudes

  - tundra is characterised by low growing plants adapted to retain heat and moisture in the cold, windy and dry conditions. These regions are found in northern canada and cross northern europe. It is a fragile ecosystem easily damaged by humans and threatened by developments such as oil exploitation and tourism. animals such as reindeer are adapted to survive the cold
• where are the rainforests and what is the climate like?

  - central and south america

  - central africa

  - southeast asia

  - northern australia

  - tropical rainforests thrive in warm and wet conditions.The equatorial zone where they are found is characterised by high rainfall; ( over 2000mm a year ) and high temperatures ( averaging about 27 degree celsius) throughout the year eg the amazonian rainforest -> temperature is high and constant throughout the year. This is because the powerful sun is overhead most of the time, rainfall ids high 9
• describe the distribution of tropical rainforest

  about 5 degree north and south of equator, tropical rainforests covers about 6% of world's land surface , largest area of rainforest in south america and others include congo basin and south east asia

  ( near equator between tropic of cancer , tropic of capricorn)

  - continents - south america, south east asia, africa

  countries - brazil, indonesia, malaysia, congo
• tropical rainforests have an equatorial climate. Temperatures are high but annual temperature range is small why

  the temperature is constant most of the time because the powerful sun is overhead most of the time
• the total annual precipitation is often in excess of 2000mm because there are intense conventional rainstorms each afternoon. Why?


  - due to a period off intense rainfall when the equatorial low pressure area is directly overhead . An area of low pressure - air rises and cools, water condenses into clouds, conventional rainfall. however, there is a distinct wet season of 6 months when the equatorial low pressure is directly overhead
• tropical rainforests are very biodiverse. Over half of all plant and animal species on the planet are found here. and often up to 100 species in a single hectare. despite this, the soils are surprisingly infertile. Why?


  - most nutrients are found at the surface , where dead leaves decompose rapidly in hot and humid conditions . Because the heavy rainfall washes out the nutrients such as potassium and calcium through leaching
• if soil is so infertile, how do tropical rainforests support such biodiversity

  nutrient cycling
• Nutrient cycling in tropical rainforests - gersmehl diagram

  - the majority of nutrients are stored in biomass because there are so many trees and plants. there are few nutrients in litter due to rapid decomposition by fungi and bacteria that thrive in warm and wet conditions. despite high rates of decomposition few nutrients are stored in the soil. This is due to rapid uptake by plants and significant leaching causes by heavy rainfall. the warm wet tropical climate promotes processes such as decomposition, weathering and leaching accounting for the rapid recycling of nutrients shown by thick arrows
• different layers ( types of plants and animals ) in rainforest

  birds mostly live in the canopy, feeding on nectar from flowers

  - mammals like monkeys and sloths are well adapted to living on trees

  - animals like deer jaguar and rodents live on forest floor as well as many species of fungi and bacteria
• The different layers of the tropical rainforest

  - shrub layer and ground layer 5m

  - lower tree canopy 10m

  - middle canopy 15m

  - top canopy 15m