7 | People And The Biosphere Flashcards
(32 cards)
What are the 7 major biomes?
Tropical rainforest, tropical grassland (Savannah), desert, boreal forest, tundra, temperate grassland, temperate forest
Climate characteristics of a tropical rainforest.
- Hot all year round as it’s near the equator (25-30°C)
- Wet all year (annual precipitation; 200-3000mm)
- Day length of around 12 hours
Distinctive vegetation of a tropical rainforest.
- Dense forest, several layers of tree
- Nutrient dense soil due to fast decomposition rate
- Fast nutrient cycling
Climate characteristics of tropical grasslands (Savannah).
- Hot all year (25-35°C)
- Annual precipitation of 500-1000mm of rainfall per year
- Distinct wet and dry seasons
Distinctive vegetation of tropical grassland (savannah).
- Tall grass
- Drought adapted shrubs and trees (baobab)
Climate characteristics of deserts.
- Hot all year (>30° C)
- Diurnal temperature range - cool nights
- Low precipitation (<250mm annually)
Distinctive vegetation of deserts.
- Plants are scarce but have water storing features (cacti)
- Spines instead of leaves and extensive root systems
Climate characteristics of temperate grassland.
- Summer: Hot (25°C)
- Winter: Very cold (-40°C)
- Late spring and summer: 500-900mm of annual precipitation
Distinctive vegetation of temperate grassland.
- Short grass
- Few trees and bushes
Climate features of temperate forests.
- Warm summer (18°C)
- Cold winter (5°C)
- Precipitation yearly (1000mm)
- Four seasons and corresponding day lengths like the UK (e.g. winter has short days and summer has longer ones)
Distinctive vegetation of temperate forests.
- Broad leaves trees that drop their leaves in Autumn
- Oak, brambles, undergrowth (fern)
- Deciduous trees
Climate features of boreal forests.
- Mild summer (10-20°C)
- Very cold winter (well below -20°C)
- Clear skies in daylight hours
- Low precipitation that usually occurs during the summer (annually <500mm)
Distinctive vegetation of boreal forests.
- Coniferous trees such as pine and fir.
- Evergreen trees
- Mosses and lichen
Climate features of tundra.
- Mostly below -20°C in the winter
- 10°C in the summer
- Short daylight hours in winter
- Long daylight hours in summer
Distinctive vegetation of tundra.
- Cold climate and lack of light and organic matter means very few plants live in the tundra
- Mainly lichens and mosses
How does latitude affect the temperature of biomes?
- Locations near the equator will receive more intense sunlight and are subsequently warmer than those near the Poles.
- If near the equator there is always high angle of sun (all year)
- Lack of heat and light limits vegetation growth and development in the poles
How does latitude affect precipitation?
- North and south of the equator there are three major convection cells (Hadley, Ferrel and Polar).
- Air pressure is low at the rising parts of these cells so precipitation is high and vice versa.
How does continentality affect how wet a biome is?
Oceans retain heat and provide moisture, so the further from the sea you are the drier it will be.
How does altitude affect biome distribution?
- The higher the altitude, the colder it gets and the more wind and precipitation there is.
- E.g. on the slopes of Mt. Kilimanjaro the biomes are tropical rainforests and the higher you go it is a tundra.
Local factors affecting biomes: Rock type/Soil
- Permeable rock (limestone) and impermeable rock (marble)
- Chemical weathering of rocks (influences how nutrient dense the soil is) affects the acidity/alkalinity of the soil which affects which plants grow there
Soil types and characteristics
- Sandy soil drains water so it is dry, doesn’t support many plants
- Clay soil doesn’t allow much water drainage so puddles of water stay on top holding nutrients and supporting wheat and grass.
- Peat has decayed plants and is rich in nutrients, supports forestry.
What is altitudinal zonation?
Change in ecosystems at different altitudes caused by changes in temp., precipitation, sunlight and soil type.
Interaction of biotic and abiotic components: What is the hydrological cycle regulation?
Plants regulate the hydrological (water) system,
E.g. trees intercept and absorb rainfall, reducing surface run off, reducing flooding risk.
In Pakistan in 2010 floods were blamed on illegal logging.
Transpiration of plants returns moisture to the atmosphere,
Interaction of biotic and abiotic components: Photosynthesis and respiration
Plants take in carbon dioxide and release oxygen, and animals do the opposite meaning that gases are regulated in the atmosphere.
