People and the Biosphere Flashcards
Biomes
Large scale global ecosystems with distinctive vegetation
What does an eco-system include?
all the living and non-living things in an area
What determines the the type of biome that forms in an area?
the climate
location of different biomes on map
(look at map)
Climate in TROPICAL RAINFOREST
same all year round - no definite season
as it is near the equator:
- temperatures are generally between 20-28°C
- day length is the same (12hrs) all year round - forest gets plenty of sunshine
very high rain fall - around 2000mm per year
rains everyday usually during afternoons
Plants in TROPICAL RAINFOREST
most trees are evergreen - they take advantage of continual growing season
grow quickly
adapted to take max light
Animals in TROPICAL RAINFOREST
dense vegetation provides lots of food and different habitats - so lots of different species of animals
examples of animals - gorillas, jaguars, anacondas, tree frogs, sloths
lots of insects and birds
Climate in TEMPERATE FORESTS
four distinct seasons
summers are warm and winters are cool
very high rainfall - up to 1500 mm per year
rains all year round
shorter days in winter and longer in summer - hours of sunshine vary through year
Plants in TEMPERATE FORESTS
mild, wet climate support less plants than tropical forest but more than boreal forest
forest made up:
- broad-leaved trees - drop their leaves in the autumn
- shrubs
- undergrowth
Animals in TEMPERATE FORESTS
mild climate and range of plants provide food and habitat for mammals, birds and insects
Soil in TEMPERATE FORESTS
plants lose their leaves in autumn
leaves litter decomposes quickly in the moist mild climate - soil is relatively thick and nutrient rich
Climate in BOREAL FORESTS
short summers and long winters
in winter average temperatures are below -20°C
in summer average temperatures are about 10°C
low precipitation - less than 500 mm per year
a lot of precipitation falls as snow
get lots of daylight during summer months
gets little or none daylight during winter
skies tend to be clear - during daylight hours there’s is plenty of sunshine
Plants in BOREAL FORESTS
most trees are evergreen - so they can grow whenever there's enough light common plants : - coniferous trees - pine and fir - moss - lichen
Animals in BOREAL FORESTS
relatively few species compared to tropical - as there is less food and animals need to adapt to cold climate to survive animals that live in boreal forest: - black bears - wolves - elk - eagles
Soil in BOREAL FORESTS
cool dry climate - means needles from trees decompose slowly so soils are thin, nutrient poor and acidic
some areas of ground is frozen most of the year
Climate in GRASSLAND
low rainfall - 800-900 mm per year
distinct wet and dry seasons
temperatures are highest (35°C) just before wet seasons
temperatures are lowest (15°C) just after
found around equator - get lots of sunshine all year round
Effects of low rainfall in GRASSLAND
too low to support many trees in tropical or temperate grassland which effects animals and soils
What does TROPICAL GRASSLAND consist of?
mostly grass, scrub and small plants with a few scattered trees (acacia)
many insects - grasshoppers, beetles, termites
large animals - lions, elephants, giraffe, zebras, antelope
Describe soil in a TROPICAL GRASSLAND
grass dies back during the dry season
this forms thin, nutrient rich soil
but nutrients is washed out of the soil during wet season
What does a TEMPERATE GRASSLAND consist of?
mostly grass, small plants and very few trees
fewer animal species than tropical grassland
mammals - bison, wild horses, rodents
Describe soil in TEMPERATE RAINFOREST
high temperatures in summer mean decomposition is fast - soils are relatively thick and nutrient rich
Climate in DESERTS
low rainfall - less than 250mm per year
might only rain once every two or three years
hot desert temperatures range from very hot in the day (45°C) to cold at night (below 0°C)
hot deserts get more day light during summer than winter - due to little cloud cover
get lots of hours of sunshine every day
Plants in DESERTS
growth is sparse due to lack of rainfall
plants :
- cacti
- thorn bushes
Animals in DESERTS
Relatively few animals species living in hot deserts
those that do are adapted to cope with harsh climates
animals :
- lizards
- snakes
- insects
- scorpions
Soil in DESERTS
sparse vegetation - so little leaf litter
dry climate - so organic matter is slow to decompose
due to this soil is mostly thin and nutrient poor
Climate in TUNDRA
low temperatures - around 5-10°C during summer and lower than -30°C in the winter
low precipitation - less than 250 mm per year
most of the precipitation falls as snow
found at high latitudes - gets near continuous daylight in summer and little or no daylight during winter
more cloud cover during summer
Plants in TUNDRA
cold climate and lack of light in winter makes it harder for plants to grow plants : - mosses - grasses - low shrubs - hardly any trees
Animals in TUNDRA
cold climate and lack of vegetation - means there are relatively few animals
animals:
- artic hares
- artic foxes
- mosquitos
- birds
some animals migrate south for winter (warmer)
Soil in TUNDRA
sparse vegetation produces little leaf litter
cold dry climate means organic matter decomposes slowly
due to this soil is thin and nutrient poor
there is a layer of permafrost below soil surface which can stop water from draining away
Permafrost
permanently frozen ground
How does Altitude affect biome distribution?
higher altitudes - colder
fewer plants grow there which limits number of animal species
this means not much organic matter so soil is thin or non existent
How does Rock-type affect biome distribution?
some rock types are:
- easily weathered to form soils
- contain different minerals - affects how nutrient rich it is
- permeable
- impermeable
How does Soil-type affect biome distribution?
more nutrient rich soil can support more plants
acidity and drainage also carries - affects type of plants that can grow
How does Drainage affect biome distribution?
poor drainage - soil gets waterlogged and only plants adapted to wet conditions can grow
Biotic components
living parts of a biome - plants and animals
Abiotic components
non-living components - soil, water, rock, atmosphere
Biosphere
includes all the parts of the earth that are occupied by living organisms - plants, animals, bacteria, fungi, soil, water
What resources does the Biosphere provide?
Food
medicine
building materials
fuels
food in biosphere
indigenous people get their food directly from plants and animals
foraging, picking wild fruits/veg/nuts, hunting
others grow food - cereals, fruits, veg, raise livestock
medicine in biosphere
lots of plants have medicinal properties - can be used to cure illness or keep people healthy
plant species in tropical forest has been used to create over 7000 drugs
building materials in biosphere
using trees and other plants
pine from taiga forest - used to make furniture and build houses
tree sap - glue or make buildings waterproof
reed and straws - roofs
plant fibres - ropes
fuel in biosphere
indigenous people rely on plants/animals for fuels for cooking and keeping warm
wood, moss, dried grass and dried animals dung - burnt as fuel
indigenous people in areas with low vegetation (tundras) use animals fat - blubber from seals as fuel for oil maps
Why is demand for energy increases
population is increasing and people have more technology
why are large areas of forest being cut down?
to clear land for the growing of crops that can be used as biofuels or to make way for coal mines or power stations
How have areas of tropical rainforests been flooded?
by building hydroelectric dams
How is the tundra biosphere being damaged?
drillings for oil and gas is damaging the biosphere because the pipelines are melting the permafrost
Why is demand for water increasing?
increase in global population - people use water for washing, irrigating farmland etc
Where are water sources currently being over-exploited? What are the effects of this?
in arid areas like the Sahara Desert
can cause damage to the biosphere - plants and animals no longer have enough water to survive
How are minerals used?
minerals such as gold and iron used in building scientific instruments, electrical appliances etc
How are minerals extracted?
mining
Effects of mining in the tropical rainforest
responsible for lots of deforestation and toxic chemicals are washed into streams and rivers - kill wildlife
How does the Biosphere control the proportion of different gasses in the atmosphere?
plants take in CO2 and give out oxygen during photosynthesis
animals take in oxygen from air and give out CO2 when they breathe
Why is maintaining balance of gasses in the atmosphere important?
- most living organisms need oxygen to serve
- increased levels go CO2 lead to global warming, make oceans acidic
- some CO2 is needed to keep the earth warm enough to sustain life
What spreads nutrients through soil?
plant roots and animals such as earthworms
this helps maintain soil structure and fertility - allows plants to grow
What holds soil together?
roots of vegetation
without this soil can be eroded by wind and rain
How does vegetation effect rainfall?
Intercepts it before it reaches the ground
helps prevent leaching
Leaching
nutrients in soil is washed downwards out of reach of plants
Water cycle
movement of water between land, bodies of water and the atmosphere
How does biosphere control the water cycle?
water is taken up by plants so less reaches rivers - this prevents flooding and soil erosion
plants also help to regulate the global water cycle by storing water and releasing it into the atmosphere slowly
Population projections
predictions of how many people there will be in the world in the future
UN predictions
UN has made 3 predictions about population growth up tot the end of this century
highest shows worlds total pop reaching 14 billion
Factors which are increasing demand for resources
wealth
urbanisation
industrialisation
How does Increasing wealth increase demand for resources?
people have more disposable income - affects resource consumption
more money to spend of food - buy more than they need
can afford cars/fridges/television - use more energy
more people can afford flushing toilets, showers, dishwashers - increases water use
How does Urbanisation increase demand for resources?
cities are more resource intensive than rural areas
street lights - energy
fountains - water
food and water have to be transported long distances to meet increased demand in cities and waste needs to be removed - increased energy use
How does Industrialisation increase demand for resources?
manufacturing goods such as cars, chemical and electrical appliances use lots of energy
can also use lots of water
as countries become more industrialised demand for water and energy increases
What is Malthus’s Theory?
He though population was increasing faster than supply of resources so eventually there would be too many people for the resources available
What did Malthus believe would happen once the population surpassed the supply of resources?
people would be killed by famine, illness, was
population would return tin a level which could be supported by the resources available
What is Boserup’s Theory?
Her theory was that however big the worlds population grew, people would always produce sufficient resources to meet their needs
What did Ester Boserup think would happen if the resources become limited?
people would come up with new ways to increase production in order to avoid hardships
Urbanisation
growth in the proportion go a country’s population living in urban areas
Industrialisation
the shift in a country’s main economic activity from primary production to secondary production
