What is a biome? What do they include?
Large scale global ecosystem
Ecosystems include all living and nonliving things
Describe the climate of a tropical forest?
Same all year around Its hot (20-28°c) Near the equator Day length is the same all year around Rainfall is very high (2000mm a year)
Describe the characteristics of tropical forests?
Plants- most are evergreen, plants grow quickly, adapted to take in maximum light
Animals- lots of food available due to dense population, lots of habitats
Soil-plants grow quickly so they shed leaves. Constant supply of nutrients.
Describe the climate in temperate forests?
Four distinct seasons Summers are warm Winters are cold Rainfall is very high (1500mm a year) Days are shorter in winter and longer in the summer
Describe the characteristics of a temperate forest?
Plants- mild wet weather means fewer species, made up of broad leaved trees that shed leaves in autumn.
Animals-range of plants gives variety of food for animals
Soil- plants lose leaves in autumn, leaf litter decomposes quickly in moist mild climate. Soil is thick and nutrient rich
Describe the climate of boreal forests?
Short summers and long winters
Temp average below -20°c in winter And 10°in summer
precipitation is low (500mm) mostly snow
Lots of daylight in summer not much in winter
Describe the characteristics of boreal forests
Plants- mostly evergreen (coniferous) trees have needles
Animals- few animal species, less food, must be adapted to cold
Soil- needles tale a long time to decompose, soil is thin and nutrient poor
Describe the climate in tropical grasslands?
Low rainfall Distinct wet and dry seasons Temperature highest just before the wet season (35°) and lowest after it (15°) Found around the equator Lots of sunshine
Describe the climate in temperate grasslands
Hot summers(40°c) Cold winters (-40°) 250-500 mm of precipitation a year
Describe the characteristics of tropical grasslands
Plants-grass, shrubs, small plants
Animals, lots of insects, lions elephants etc
Soil-grass dies during dry season forming a thin nutrient rich soil but wet season washes nutrients out.
Describe the characteristics of temperate grasslands
Plants-dominated by grasses and small plants, few trees
Animals- wild horses, mole rats
Soil-soil is thick and nutrient rich
Describe the climate in the desert
Rainfall is low
Hot temp (45°c) in day, cold at night (below 0°)
Lots if sun as little cloud cover
Describe the characteristics of deserts
Plants- little rainfall means little vegetation
Animals- few animals, camels, lizards, snakes
Soil-thin and nutrient poor
Describe the climate of the tundra
Low temps (5-10°) in summer and lower in winter (-30°) Low precipitation Found at high altitudes. Near continuous daylight in summer Little or no sunlight in winter
Describe the characteristics of the tundra
Plants- lack of light and cold makes it hard for vegetation to grow
Animals- few species of animal due to cold conditions
Soil-little vegetation means it is nutrient poor. Laters of permafrost below soil surface stops water from draining away.
What affects the distribution of biomes
Altitude- higher altitudes are colder
Rock type-some rock types are easily weathered to form soils
Soil type-more nutrient rich soils support more vegetation
Drainage-if drainage is poor soil gets waterlogged.
What sort of resources does the biosphere produce?
Food
Medicine
Fuel
Building materials
How do humans exploit the biosphere?
Energy- increasing population increases demand. Crops grown here can be burnt to make biofuels. Large spaces are cleared for coal mines or power stations.
Water- water is being taken from the biosphere due to increasing population. This is bad as plants and animals wont have as much water.
Minerals- gold and iron can be used for buildings and lots of other things. They are extracted by mining
How does the biosphere help regulate gases?
Plants take in carbon dioxide and release oxygen
Animals take in oxygen and and give out carbon dioxide
What does the biotic components of a biome mean
The biotic components of the living part of the biome e.g. plants and animals
What does the abiotic components of a biome mean
The abiotic components of the nonliving parts e.g. soil water rock atmosphere
What are some examples of how the biotic and abiotic components of biomes interact
- Water availability affects the plants that can grow
- The type of density of vegetation grows affect the type of soil that forms
Why is it important to maintain the balance of gases in the atmosphere
Most living organisms need oxygen to survive
Increased levels of CO2 lead to global warming
Increased levels of CO2 can also make the oceans acidic affecting organisms that live there
Some CO2 is needed to keep that woman off to support life
What is the water cycle
The water cycle is the movement of water between the land, bodies of water and the atmosphere
How does the water cycle go
Clouds form It rains Water runs to the rivers and the sea Water evaporates Repeat
How is the biosphere an important control on the water cycle
Water is taken up by plants, so less reaches rivers preventing flooding and soil erosion
Plants also help regulate the global water cycle by storing water and releasing it slowly
How can an increased demand for one resource increase demand for another
More people means more food. This means an increase in demand for water
How was increasing wealth increased demand on resources
Wealthier people have more disposable income.
They have more money to spend on food and they often buy more than they need
They can afford cars, fridges, televisions all of which is energy. Manufacturing these goods and producing energy to random water uses a lot of water
How is increased urbanisation increased demand for resources
Cities tend to be more resource intensive than rural areas. Street lights and neon signs use energy and Fountains in urban parks require water
How has increased industrialisation increased demand for resources
Manufacturing goods uses a lot of energy. Manufacturing also uses a lot of water. As countries become more industrialised the demand for energy and water increases
Industrialisation is increasing the production of processed goods. This increases the demand for ingredients such as palm oil
Who was Thomas Malthus
Thomas Malthus was an 18th century economist
What did Thomas Malthus believe
I thought that population was increasing faster and supply of resources so eventually they would be too many people for the resources available
He believed that, when this happened, people will be killed by catastrophes such as famine, illness and war, and the population would return to a level that would be supported by the resources available for
Who was boserup
Ester boserup was a 20th century economist
What did Esther Boserup believe
Her theory was that however big the worlds population grew people would always produce sufficient resources to meet their needs
She thought that if resource supplies became limited, people would come up with new ways to increase production in order to avoid hardship
