content - biomes Flashcards
(41 cards)
1
Q
typical characteristics for a tropical forest
A
- hot all year = 25 - 30 degrees
- wet all year 2000 mm of rain
- dense forests with several layers of trees + all competing for light
2
Q
typical characteristics for a temperate forest
A
- warm summers - around 18 degrees
- cool winters - around 5 degrees
- rain all year round - around 1000mm
- DECIDUOUS TREES such as OAK
3
Q
typical characteristics for a boreal forest
A
- mild summers - around 10-20 degrees
- very cold winters - below 0 degrees
- low precipitation - less than 500 mm mainly in summer
- CONIFEROUS trees such as PINE
4
Q
typical characteristics for a tropical grassland
A
eg. SAVANNA
- hot all year - 25-35 degrees
- always has a dry season
- only 500- 1000mm of rain per year
- tall grasses, with some drought - adapted shrubs and trees eg. BAOBAB
5
Q
typical characteristics for a temperate grassland
A
- hot in summer = 25 degrees
- very cold in winter = as low as -40 degrees
- 500-900mm of rainfall
- short grasses with very few trees and bushes
6
Q
typical characteristics for a desert
A
- very hot all year - above 30 degrees
- cool nights = large diurnal temperature range
- very low rainfall - below 250 mm a year
- plants are scarce and have water storing features = spines instead of leaves and extensive root system = eg. CACTI
7
Q
typical characteristics for tundra
A
- temp below 0 degrees for most of the year
- reaches about 10 degrees in summer
- low rain - less than 250mm
- short-daylight hours in winter
- very few plants can survive here mainly - LICHENS and MOSSES
- trees are rare and stunted
8
Q
how are the biomes influences by temp
A
- concentration of solar energy
9
Q
how are the biomes influenced by rainfall
A
- rising / sinking air
- dense vegetation
10
Q
how are the biomes influences by sunshine hours
A
- less growth period
- lower rates of photosynthesis
11
Q
how does altitude effect biome distribution
A
- forest biomes decrease with altitude, becoming stunted and replaced with hardier species eg. grases
BECAUSE
- temp fall at approx 1 degree per 100m
- mountains more exposed to wind
- precipitation usually greater at higher altitudes
- slopes steeper
- soils thinner
12
Q
how does rock type effect biome distribution
A
- rock hardness = granite hard vs chalk soft
- permeability = sandstone permeable vs slate impermeable
- LIMESTONE = produce ALKALINE soils + due to permeability are very dry = these factors lead to beech trees replacing oak tree growth
13
Q
how does soil type effect biome distribution
A
- sandy soils = pale coloured with lots of small air gaps / water drains through easily so usually quite dry / plants must have tolerance to drought / supports RYE + BARLEY + SOME ROOT CROPS
- clay soils = orange / very few air gaps / water doesn’t drain through easily / puddles stay on top for a while / holds nutrients well - WHEAT + BEANS + GRASS
- chalky soil = light brown / water drains through - GRASS + BARLEY
- Peat = doesn’t contain rock particles like others / made from oil - decayed plants / dark crumbly + rich in nutrient / acidic - FORESTRY
14
Q
how does drainage effect biome distribution
A
- impermeable rock = surface becoming frequently waterlogged because rain can not drain away
- water-logging can prevent trees from growing + PEAT BOGS pr other mashed may form = only specially adapted plants eg. BULUSHES
15
Q
biotic factors
A
- Flora
- Fauna
16
Q
abiotic factors
A
- Soils
- Rock
- Water
- Atmosphere
17
Q
How do abiotic and biotic components interact in a biome
A
- sometimes flora and fauna can secrete acids which dissolve rocks = bio-chemical weathering = most plants do this when they decompose producing humid acid
- photosynthesis + respiration
- nutrient cycle
18
Q
How does the biosphere provide recourses for indigenous and local people
A
- Food - howwwww
- Medicine
- Building materials
- Fuel resources
19
Q
How / why is the biosphere increasing exploited commercially for energy
A
- biofuels = valuable alternative to fossil fuels = because renewable
- commercial production of biofuels means that high areas of land has to be deforested for biofuel crops
- impacts biodiversity
20
Q
How / why is the biosphere increasing exploited commercially for water
A
- huge demand for water = population growth / urbanisation / agriculture
- means that other parts of the biosphere are deprived of water eg. HAMOUN WETLANDS = wetlands dried up due to droughts + rapid population growth
21
Q
How / why is the biosphere increasing exploited commercially for mineral resources
A
- coal mining
- remove tops of mountains
22
Q
How does the biosphere regulate the composition of the atmosphere
A
- respiration animals
- photosynthesis plants
23
Q
How does the biosphere maintain soil health
A
- leaf litter decomposes ( by decomposers) in the presence of warm wet conditions to produce rich HUMUS
24
Q
How does the biosphere regulate water within the hydrological cycle
A
25
Global and regional trends - there is an increasing demand for..
- Food
- Energy
- Water resources
26
why is there an increasing demand for these things
- Population growth
- Rising affluence
- Urbanisation
- Industrialisation
27
Malthus
* believed that the human population would grow faster than food supply and a disaster would then take place = social unrest / fighting / famine / epidemics
* argued that population increased geometrically whereas supplies only increased arithmetically
* point of catastrophe
* EVIDENCE = EBOLA DISEASE SPREAD / CIVIL WAR
28
Boserup
* believed that as population approaches the point where food and resources may run out = then human INGENUITY will find ways of increasing food production
* **necessity is mother of invention**
* as carrying capacity is approached = people will find solutions
* evidence = the green revolution = use of selective plant breeding / irrigation / fertiliser = INCREASE YIELD + BIRTH CONTROL
29
distribution of tropical rainforest
* occurs where there is year-round high temps + high precipitation
* occurs near the equator because the sun is more direct
* heat causes air to rise = cools = condenses = clouds = high rainfall
30
define inter-tropical convergence zone
a belt of low pressure around the earth, just north and south of the equator where warm, moist trade winds come together
atmospheric systems of northern hemisphere and Southern Hemisphere come together
31
distribution of tropical grassland - savanna
* occurs further from the equator than tropical rainforest
* temp still high but there is a pronounced dry season, preventing dense tree growth
* tall grass eg. ELEPHANT GRASS thrive here
32
distribution of hot desert biome
* occurs around tropics of cancer and Capricorn because air is sinking here
* sinking air warms so can hold more moisture
* so there is little condensation and cloud forming
* creates high pressure
* high temp during the day ( because sun is still up and no clouds to protect) but cooler at night ( because no clouds to act as a blanket)
33
distribution of temperate forests
* occur at high latitudes eg. UK
* atmosphere consists of many low pressure systems = rain all year round
* in winter = sun lower in the sky = less sunlight hours = slowing photosynthesis
* DECIDUOUS trees save energy + protect themselves from cold temps by dropping their leaves in autumn
34
distribution of temperate grasslands
* similar latitudes to temperate forests
* seasons are more pronounced as away from moderating effect of the oceans = in the middle of continents
35
distribution of boreal forests
* occur north
* found where temp is colder = air sinking which leads to low rain
* conifer trees have waxy needle-like leaves = coating + small SA protect from cold
* often snow = trees have sloping branches to allow snow to fall off
36
distribution of tundra
* occurs closets to the poles
* plant growth limited by the very low temps + short sunlight hours
* sinking air = low rain
37
HARD ROCK
GRANITE
38
SOFT ROCK
CHALK
39
PEAT BOG
a wet, spongey area where the soil is made up from decayed plant material
40
nutrient cycle
* as animals and plants die their tissues fall in the litter store
* as living tissue decomposes, nutrients are transferred to the soil store
* some nutrients are lost from litter nu surface run off
* some nutrients are taken up by plants in the soil
* some nutrients are lost by leaching
41
exploitation
* demand for palm oil = used in shampoo + ice cream = lead to massive deforestation in CAMEROON
* demand for beef has lead to massive deforestation in AMAZON = cattle ranching
* huge HEP projects lead to flooding behind dams = SANTA ANTONIO DAM IN BRAZIL + THREE GORGES DAM IN CHINA
* massive swatches of boreal forest have been destroyed through **OPEN CAST MINING** of the Alberta tar sands
