Studied by 4 people
when dead materials decomposes nutrients are released into soil
nutrients taken up from soil by plants; plants may be eaten by consumers
when plants/consumer dies, nutrients returned to soil
high latitudes [above 60° N] in Northern Europe/Canada + Alaska
cold winters/brief summers
little rainfall
little vegetation [mosses/grasses]
layer of permafrost
found between 50-60° N
cold/dry winters
mild/moist summers
coniferous trees
found mid-latitudes
four distinct seasons
warm summers/mild winters
rainfall all year around
deciduous trees lose leaves in winter to cope with colder weather
found around equator, between the tropics
hot/wet all year around
lush forest + dense canopies of vegetation forming distinct layers
found between 15°-35° North and South of equator
little rainfall
hot during day/cold at night
shrubs/cacti are sparsely distributed in sandy soil
found around north and south poles
cold, icy and dry
dark for several months each year
short growing season
no definite seasons
It's hot (between 20-28°C)
high rainfall, 2000mm per year
evergreen/tall trees
dense vegetation cover - little light reaches the forest floor (2%)
epiphytes (plants that grow on other living plants and take nutrients and moisture from the air) e.g. orchids and ferns
high biodiversity, 50% of world's plant, animal and insect species
stable/productive environments from the constant climate (hot + wet)
organisms evolved to depend on few species for survival
deforestation
uncontrolled development
warm/wet climate helps fungi/bacteria decompose dead plant material making surface soil high in nutrients, meaning plants grow easily
nutrient cycling
plants and animal species formed symbiotic relationships (dependent on the other for survival)
[deforestation]
trees intercept and take up lots of water
reduced tree covers increases risk of drought affecting wildlife
trees roots stabilise soil and provide nutrients when leaves drop
fewer trees mean soils has less protection for rainfall, nutrients will wash away and plants struggle to grow
trees compete for sunlight by growing tall
thick, waxy leaves with pointed drop-tips channel rainwater to encourage runoff -> leaves' waxy coating coating helps repel the rain
lianas use tree trunks to reach sunlight
smooth and thin bark helps water to run off
large, stable buttress roots support the tall trees' trunks
plants drop their leaves throughout the year, so they can grow all year round
layer receives 2-15% of sunlight
spacious containing young trees and herbaceous plants tolerating low light
receives less than 2% of sunlight
little grows here
floor is a thin layer of fallen leaves, seeds, fruits and branches that decompose
strong limbs to move around habitat quickly and easily e.g. monkeys
birds have short pointed wings to manoeuvre between dense tangled trees
suction cups help animals climb
some animals can swim, e.g. jaguars
nocturnalism conserving energy in cooler territory e.g. sloths
camouflage to hide from predators
global rate of deforestation is high, from 2007-2017, average of 22m hectares of forest were lost each year
countries are working to reduce deforestation rates, e.g. from 2004-2012, rate of deforestation in Brazil decreased by about 80%
rubber, coffee, chocolate and medicines, are sourced from the rainforest
Sustainable development offers long-term economic benefits e.g. ecotourism
trees to continue absorbing CO2 and reduce global warming
regulate climate/water cycle - without them the risk of drought/flooding in areas can increase
Replanting
Selective Logging
Ecotourism
Education
Conservation
Reducing Debt
New trees are planted to replace ones that were cut down
It's important the same type of trees are replanted
Some countries have laws to replant trees when they are cleared by deforestation
Some trees are felled (old ones), the rest remain -> overall forest structure is kept/the canopy remains/soil is not exposed allowing forest regeneration
Least damaging form is 'helicopter logging' - dragging felled trees without the use of machinery
{e.g. Helicopter logging is used in Sarawak, Malaysia}
Small number of visitors allowed into an area at a time + rules are imposed to minimise environmental impacts
Provides a source of income for locals
{e.g. Costa Rica; 21% of country protected from development}
People can buy products to encourage sustainable sources
Locals might damage the forest to overcome poverty -> educating locals about deforestation impacts reduce damage
Teaching locals alternative ways to make money that don't damage the environment means they won't be as dependent in unsustainable options to make a living
{e.g. The Rainforest Alliance is teaching communities in Guatemala about sustainable livelihoods}
debts can be cancelled by countries/organisations meaning LIC's do not have to log/mine the rain forest to repay the money so it can be reserved
no guarantee money is spent on conversation so a conversation swap is better where a part of country's debt is paid in exchange for guaranteed money spent on conversation
{e.g. 2011, USA reduced Indonesia's debt by $29 million in exchange for conserving their rain forests}
national parks and nature reserves are set up in countries to reduce damaging activities but lack of funds makes it difficult to police the restrictions
overseas governments/businesses can invest in funds for rain forest conservation
money is used to enforce restrictions of damaging activities
{e.g. 2018, Norway paid $70 million into Brazil's Amazon Fund used for conservation}
little rainfall, less than 250 mm p/y
varied rainfall
extreme temps because lack of cloud cover reaching 45°C in the day, dropping below 0°C at night
lack of leaf fall limits soil's fertility
little rainfall so soil dries out
soil is shallow + gravelly texture
animals adapted to harsh environment
small, nocturnal mammals e.g. kangaroo rats
Birds leaves desert during harshest conditions but roadrunners live there all year
grow few crops near natural water sources, in desert fringes
indigenous people are nomadic - keep travelling to find food/water for livestock
plants take up nutrients from soil providing nutrients/water to animals that eat them; animals spread seeds through dung helping plants reproduce
hot + dry climate affects desert soil ; soils are salty due to high evaporation rates + low in nutrients from low decomposition of dead plant material by fungi/bacteria so plants struggle growing
vegetation limits food availability, desert can only support low-density populations of animals/people
roots are either deep or wide to absorb maximum water
succulent plants have large, fleshy stems to store water and thick waxy skin to reduce transpiration
small leaves/spines lowering s.a and reduces transpiration; spines contain toxins protecting plant from predators
some plants only germinate after it rains growing quickly to make most of wet conditions
nocturnal to conserve energy and stay cool
long limbs/ear giving larger s.a to lose heat from
fat that breaks down into water e.g. camels' humps
camels have triple eyelids/long eyelashes to block sand + ability to close nostrils to keep sand out, large + flat feet so they don't sink
areas with water have highest density of human populations; people threaten biodiversity by increasing desertification or over-using/contaminating water supplies
development around desert margins means habitats are divided by roads threatening animals that migrate over large distances
global warming makes deserts hotter/drier forcing species to move/become extinct
Climate Change { rainfall + temperatures }
Human Activities { removal of fuel wood + overgrazing + over-cultivation + population growth}
water management
tree planting
soil management
appropriate technology
trees act as windbreaks, reducing wind erosion
trees stabilise sand preventing desert from encroaching on farm land
growing trees amongst crops protects them and soil by providing shade, reducing temperatures and evaporation rates
leaving areas of land to rest in between grazing/planting recovers nutrients
rotating crops that take different nutrients from soil prevents same nutrients being continually removed
compost used to add extra nutrients to soil
sand fences (barriers trapping windblown sand) or terraces constructed stabilising soil + reducing erosion
rate of deforestation reduced by using solar cookers, uses the sun's energy to heat food -> cheap + easy to make not requiring fuel wood
![<ul><li><p>high latitudes [above 60° N] in Northern Europe/Canada + Alaska</p></li><li><p>cold winters/brief summers</p></li><li><p>little rainfall</p></li><li><p>little vegetation [mosses/grasses]</p></li><li><p>layer of permafrost</p></li></ul>](https://knowt-user-attachments.s3.amazonaws.com/6fb81ddfd6e543e78b7c6220f1672a2b.jpg)
