People and the Biosphere

• What are biomes?


  They are large-scale, global ecosystems
• What does and ecosystem include?

  An ecosystem includes all living and non-living things in an area
• What determines what biome an area has?

  They are determined by the climate in an area
• What are the features of a tropical rainforest climate?

  Equatorial. temperatures high all year, concentrated solar radiation, high precipitation (2000mm per annum). No definite seasons
• Why does the TRF have similar temperatures and day lengths all year round?


  It is based near the equator so the sun is almost directly above it all year.
• What are some TRF plant characteristics?

  Most trees are evergreen (don't lose their leaves in a specific season) to take advantage of the year round growing season.

  Plants grow fast and are adapted to take in maximum light.

  dense forest with several layers of trees, with other smaller plants competing for light.
• What are some TRF animal characteristics?

  Lots of species because of the wide variation of vegetation which provides food and habitats.

  Lots of insects and birds.
• What are some TRF soil characteristics?

  Plants leaves that drop all year round decompose, this provides a constant supply of nutrients in the soil, these nutrients are cycled quickly.
• What are the features of a Temperate Forest climate?

  They have 4 distinct seasons, warm summers and cool winters due to variations in the suns rays.

  High amounts of rainfall all year (1000mm per annum)

  Days are shorter in winter and longer in summer, hours of sun vary through the year.
• What are some Temperate Forest plant characteristics?

  The mild, wet climate supports less plant species than TRF but more than Boreal Forests.

  Forests usually have broad leaved trees that drop leaves in autumn, shrubs and undergrowth
• What are some Temperate Forest animal characteristics?

  The climate and range of plants provides food and habitats for mammals, birds and insects
• What are some Temperate Forest soil characteristics?

  trees lose leaves in winter and leaf litter decomposes quickly in the moist, mild climate.

  The soils are thick an quite nutrient rich.
• Taiga (boreal) forests


  - higher latitudes

  - sun's rays weaker

  - adapted to cold weather with needle like leaves
• What are the features of a Boreal Forest climate?

  mild summers (10-20)

  very cold winters (below 0)

  low precipitation (500mm) - mainly in summer
• What are some Boreal Forest plant characteristics?

  Most trees are evergreen so they can always take advantage of the small amounts of light, coniferous trees, needle like leaves
• What are some Boreal Forest animal characteristics?


  Relatively few animal species, some examples are wolves, elk, eagles and black bears
• What are some Boreal Forest soil characteristics?

  The cool dry climate means the that needles from trees decompose slowly.

  The soil is thin, acidic and nutrient poor, in some areas the ground is frozen for most of the year.
• What are some features of the Tropical Grassland (Savanna) climate?

  moderate rainfall, with distinct wet and dry seasons. Temperatures are hot all year.

  Usually near the equator / between the tropics so sun all year round.
• What are some Tropical Grassland plant, animal and soil characteristics?

  Consists mostly of tall grasses, drought adapted shrubs and trees.

  They are home to lots of insects and larger animals like lions and elephants.

  Grass died back during dry season which forms a thin nutrient rich soil but these nutrients are washed out during the wet season.
• What are some Temperate Grassland plant, animal and soil characteristics?

  Have a lot of grasses and small plants but have very few trees and less animals than tropical grasslands.

  High summer temperatures mean that decomposition is fast which leads to thick and nutrient rich soil.
• What are some features of Temperate Grassland climate?

  They have hot summers (25) , cold winter (-40 degrees) and up to 500mm of rain per year most in late spring.

  They are further down from the equator, tropics area (20-50o) so light varies around the year.
• What are the features of a Desert climate?

  Very low rainfall (less than 250mm per annum), sometimes it only rains once or twice every 2-3 years.

  Found at tropics, hot DRY air sinks down to Earth's surface and the suns rays are concentrated here making it hot.

  Hot deserts might be up to 45 degrees in the day but below 0 at night - large diurnal temperature range.

  Hot deserts get more daylight in summer than winter, because there is little cloud cover there is lots of sun every day.
• What are some Desert plant characteristics?

  Very little plant growth due to the small amount fo rainfall. water store features to survive, extensive roots.
• What are some Desert animal characteristics?

  Relatively few species, those that do live there are adapted to the harsh climate such as lizards, snakes and insects
• What are some Desert soil characteristics?

  Sparse vegetation means little leaf litter, the dryness makes decomposition slow.

  Soil is mostly thin and nutrient poor.
• What are the features of a Tundra climate?

  Low temperatures all year below 0, short mild summer (10). Low precipitation (less than 250mm), sun gives little heat at high latitudes and so little rainfall. Usually found at very high latitudes which results in almost continuous daylight in summer but short daylight hours in winter.
• What are some Tundra plant characteristics?

  The cold and lack of light makes it extremely hard to grow plants so there is usually tough short grasses, moss and low shrubs. trees are rare.
• What are some Tundra animal characteristics?

  The cold and lack of vegetation means that few animals live here, lots of birds, some mosquitoes and arctic species reside here.

  Some animals migrate south for winter.
• What are some Tundra soil characteristics?

  Sparse vegetation leads to little leaf litter and slow decomposition. The soil is thin and nutrient poor, there is also a permafrost layer below the soil which stops water drainage.
• What local factors affect biome distribution on a smaller scale?

  Altitude, Rock type, Soil type and Drainage
• How does Altitude affect biomes on a smaller scale?

  Higher altitudes are colder, high precipitation, exposure to winds, so fewer plants grow there which limits plant species. This also leads to thin or non-existent soils.
• How does Rock Type affect biomes on a smaller scale?

  Type of rock affects how nutrient rich the soil is as different rocks have different minerals so when they are weathered different qualities form.

  granite weathers slowly soil are thinner.

  limestone alkaline soils dry as highly permeable prevents tree growth.
• How does Soil Type affect biomes on a smaller scale?

  More nutrient rich soils can support more plants, acidity and drainage also affects types of plants that can grow. dry soils allow water to drain through easily, drought resistant plants.
• How does Drainage affect biomes on a smaller scale?

  If drainage is poor for example impermeable rocks then only plants adapted to wet conditions can grow there.
• What is a biotic component of a biome?


  This is the living part of a biome like plants and animals
• What is an abiotic component of a biome?

  This is the non living part of a biome like water and soil
• What is an example of biotic and abiotic components interacting?

  Water availability affects how plants can grow, it also affects soil quality which affects plant growth. Plants also release moisture into the atmosphere for further rainfall.

  Taiga biome has low biodiversity - long cold winters low precipitation frozen soils (abiotic factors) - only specialist plants are able to grow in the poor soils, low light, cold temperatures (biotic factors) - a small amount of plant food = small numbers of animals.
• nutrient cycling - shows how biotic and abiotic components interact


  How nutrients are transferred between stores of the ecosystem, varies between different ecosystems

  L = litter store

  B = biomass store

  S = soil store

  the size of the arrow shows the size of the nutrient transfer between each store.
• What resources does the biosphere provide?

  Food, Medicine, Fuel and Building Materials
• How does the biosphere provide Food?

  Many indigenous people get their food directly from plants and animals, some hunt (fish and meat) and some grow their own (sustainable harvesting of fruits, berries and nuts)