a large eco-system - grouping of plants +
animals over a large area of the Earth
eco-system
grouping of plants + animals that interact with each
other + their physical environment
degradation
the character + quality are being constantly lowered caused
by human actions
Local factors affecting biomes
Altitude
temp. drops 0.5degrees
every 100m increase
tough grasses replace trees on mountains
distance from sea
in USA + australia
inland areas have low rainfall as moisture is lost
said to be a 'rain shadow'
Geology + soils
e.g. limestone - dry soil conditions because
rainwater passes through the rock easily
little trees here due to limited water availability
A life-support system
water cycle - plants slow flow of water to rivers +
filter to make clean
plants absorb CO2 and release O2 for us to breathe
dead plants + leaves add nutrients to the soil
insects + animals burrow allowing air to circulate
goods provided to us by the biosphere
Food
natural vegetation is replaced with commercial crops
e.g. central USA 'bread basket' naturally occuring
grass replaced by wheat + corn
land used for biofuels
fish, meat, fruit, berries + nuts
Medicines
Quinine - painkiller
Periwinkle plant - leukaemia
St John's Wort - depression
Natural store of medicines is called the 'gene pool'
vitamins - oranges
Raw Materials
wood - construction of homes + boats
plant material - thatched roofs
the baobab tree -
stores water in trunk
vital water source for people living in rural areas
rainfall is rare
The importance of forests to human life
Britain - deciduous forests helped make fuel which drove
the industrial revolution
coniferous forests in Scandinavia + North
america provide much of world's softwood
pine for lightweight furniture
Tropical rainforest - wood, land + medicines
Degradation of the biosphere by human activity
mining
the grande carajas development programme, Brazil
mines aluminium + iron from huge areas where virgin forest once stood
so people can make money (economic) from the minerals found
Timber
clearance of tropical hardwood e.g. mahogany - fuelled by
demand for expensive furniture and flooring
Agricultural land - landless farmers migrate along new roads in Amazonia
deforest for firewood + to grow crops
patterns of deforestation folow road networks
soya beans
Rainforest
reasons for destruction
timber - buildings, furniture, fuel
agricultural land - crops, grazing animals
Mining/ Quarrying of minerals - contruction industry, jewellery
transport routes
Building human settlements
Building dams + power stations - power
The soya craze
the governer of Mato Grosso state is Blairo Maggi - also runs the world's largest soya bean production company
2003, first year as governer - rate of deforestation of Brazil rose by 40%
response to increased global demand
Cattle ranches (especially Europe) - switching to soya as a healthy + safe food souce for their animals
people want meat-rich diets
demand is high in emerging superpower countires e.g china
citizens have become richer in recent years
more soya bean needed to feed the
ever-growing number of cattle
People pressure
over-fishing
pantanal - giant wetland
population of pacu fish has declined
helps disperse seeds of trees
species interdependecy
population
72 million - 1960
200 million - Today
1.5% growth per annum
need land for farming + housing
Degradation
direct human actions damaging biosphere
deforestation
mining
quarrying
Farming
overfishing
ways humans detroy the biosphere indirectly
pollution + climate change (cause by C02 + CH4)
sea temp. rise
seawater acidification
melting of polar ice caps
polar bears extending their hunting range inland
changing amounts of rainfall
treeline changes
stress within ecosystems
changes
flora + fauna under stress from warming climate
droughts reported
2005 + 2010 longer-lasting drought affected a large area covering northwest, central + southwest Amazon
caused by unusual northerly shift in rain-bearing winds
amphibians, reptiles + frogs are highly sensitive to environmental change
rapid decline in frog population
temp. change - more vulnerable to disease
changes for the UK
winners
growing season in central Enland already lengthened by a
month sice 1900
can grow exotic species e.g. yucca + olive in warmer , drier southern england
new marine wildlife
more whales, sharks + sea turtles
changes in marine biodiversity
caused by warmer water suface temp.
Tree-line moving up in scottish highlands
bring greater biodiversity to upland areas
losers
changes in precipitation patterns
grasses instead of the naturally occuring deciduous forests in south-east
severe heatwave - 2006
fewer frosts and winter cold spells since the 1960s
trees could become stressed wherever water supplies are limited
(well-drained area with highly permeable soils)
a 2-4 degree change in temp.
major change in geographical distrubution of forests + plant communities
bird + animal species change
1/2 of UK's migratory birds already seen rapid decline
Biosphere conservation
global scale
The Ramsar convention
Scale: Global, 168 countries have signed treaty
Started: 1971, meeting in Iranian city Ramsar
What it conserves: 2.05 million km2 of wetlands around the world
why: Wetlands provide rich biodiversity eith many rare species
How is it threatened: Population growth means Wetlands are drained for farmland, also vulnerable to climate change
Management type: International treaty protects important wetlands by law
National scale
National Parks, UK
Scale: National
Started: 1951, peak district first
What is conserves: areas of natural beauty in the UK - 22,000km2 in 15 parks
Why: important for people's leisure, enjoyment and culture + to preserve wildlife + environment
How they are threatened: any development that would degrade the ecosystems, e.g mining, construction, overdevelopment
Management type: each park has its own authority contolling any new developmet
Local scale
The Caledonian Forest
Scale: local
important biological resource + 'environmental inheritance'for people living in Scottish Highlands
EU funding for restoration of habitat - benefit of future generations
bring back lost aniaml habitat + populations within a part of forest - Glen Affric
restore biodiversity to natural level by management strategy known as environmental stewardship
reintroduce wild-boar - made extinct by hunting
feed on forest-floor organisms e.g. fungi + insects
aids growth of trees
Acheiving a sustainable outcome
sustainable - meeding the needs of today without compromsing the
needs of future generations
econmic sustainability - continue to generate similar amounts of
money without needing lots more money put in
prevent long term damage to an ecosystem
by not polluting it, destroying plants, overfishing
educate local people- why they need to manage ecoystem for their own benefit
e.g. teach sustainable farming methods that won't exhaust the ecosystem
help them benefit socially + economically without damaging environmentally
e.g. helping them to irrigate land better tp produce more crops to sell + eat + keep soil norished/ helping them to make a living
through environmental tourism - help conserve environment whilst economically benefitting local people
tensions
social
reintroducing wolves + bears in Europe + North America - regarded as dangerous
must bebefit all groups
Economic
rising population + resource consumption due to poverty reduction e.g. Brazil, China
want to build econmomic progress - may exploit environment to do so e.g. deforestation of the Amazon Rainforest
Environmental
reintoducing species and protecting environments e.g. wetlands
not harming natural resouces so they cannot regnerate