Topic 7: People & The Biosphere Flashcards
What are biomes?
Large-scale, global ecosystems with distinctive vegetation
Why do different parts of the world have different biomes?
The climate in an area determines what type of biome forms. So different parts of the world have different biomes as they have different climates
Name 3 biomes
- Tropical forest
- Temperate forest
- Boreal forest
Climate of Tropical forests
- Same all year round, no definite seasons
- Hot (temperatures 20-28 degrees) due to being near the equator
- Day lengths are the same all year round (12hrs) due to being near the equator, so recieves plenty sunshine all year
- High rainfall (2000mm per year), rains everyday
Characteristics of Tropical forests
Plants - most trees are evergeen to take advantage of the continual growing season. Plants grow quickly & are adapted to take in maximum light
Animals - the dense vegetation provides lots of food & different habitats, so there are lots of different species of animal (gorillas, jaguars, etc). Lots of species of insects and birds
Soil - plants grow quickly & shed leaves all year round. These decompose quickly, so theres constant supply of nutrients in soil that are cycled quickly
Climate of Temperate forests
- 4 distinct seasons. The summers are warm & winters are cold
- High rainfall (1500mm per year), all year round
- Shorter days in winter, longer in summer. Hours of sunshine vary through the year
Characteristics of Temperate forests
Plants - the mild, wet climate supports fewer plant species than tropical forests, but more than boreal forests. Forests made up of broad-leaved trees that drop leaves in autumn, shrubs & undergrowth
Animals provides food & habitats for mammals (eg. foxes, squirrels), birds and insects
Soil - plants lose their leaves in autumn, leaf litter decomposes quickly in moist, mild climate. Meaning soils are relatively thick & nutrient-rich
Climate of Boreal forest
- Short summers & long winters. Average temperature in winter is below -20 degrees, and 10 degrees in summer
- Low Precipitation (less than 500mm per year), mostly falls as snow
- Lots of daylight during summer, but little to none during winter. Clear skies so plenty of sunshine in daytime
Characteristics of Boreal forest
Plants - most trees evergreen, so can grow whenever theres enough light. Coniferous trees (pine & fir) are common, as are low-growing mosses & lichen
Animals - relatively few animal species (eg. black bears, wolves, eagles) compared to tropical forests because less food available & animals need to be adapted to the cold climate to survive.
Soil - cool, dry climate means needles from trees decompose slowly, so soils are quite thin, nutrient-poor and acidic. In some areas, ground is frozen most of year
What are the 2 types of Grassland
- Tropical grassland
- Temperate grassland
Climate in Tropical grasslands
- Quite low rainfall (800-900mm per year)
- Distinct wet and dry seasons
- Temperatures are highest (35 degrees) before wet season & lowest (15 degrees) just after it
- Found near equator, so recieve lots of sunshine all year round
Characteristics of Tropical grasslands
Plants - consists mostly of grass, scrub & small plants, with few scattered trees
Animals - home to lots of insects (grasshoppers, beetles), larger animals include (lions, elephants)
Soil - grass dies back during dry season forming a thin, nutrient-rich soil, but nutrients are washed out of soil during wet season
Climate of Temperate grasslands
- Hot summers (up to 40 degrees) & cold winters (-40 degrees)
- Lower rainfall than tropical grasslands (250-500mm per year)
- As further from equator, the amount of light recieved varies throughout year
Characteristics of Temperate grasslands
Plants - Much like tropical grassland, dominated by grasses & small plants, very few trees
Animals - home to fewer animal species than tropical grasslands, mammals (bison, wild horses), rodents (mole rats)
Soil - high temperatures in summer means that decomposition is fast, so soils are relatively thick & nutrient-rich
Climate of Deserts
- Very low rainfall (less than 250mm per year). Might only rain once every 2-3 years
- High temperatures range from 45 degrees at day and 0 degrees at night
- Recieve more dayligt during the summer than winter. Little cloud cover, so lots of sunshine everyday