A community of plants and animals that interact with eachother and the physicalenvironment
what is biotic?
living things eg. Animals
What is abiotic?
Non-living things eg. Water
What is an example of a small-scale ecosystem?
A pond
Global - scale ecosystems
Eg. Tropicalrainforests
These global ecosystems are called biomes
What is nutrient cycling?
When plants or animalsdie, decomposers help to recycle The nutrients making them available once again for the growth of plants and animals
What do producers do?
Convertenergy from the environment (mainly sunlight) into sugars (glucose)
Eg. Plants that convert energy from the sun by photosynthesis
What do consumers do?
Get energy from sugars produced by producers
Eg. Pondsnail eats plants
what do decomposers do?
Breakdownplant and animalmaterial and return nutrients to the soil
Eg. Bacteria
What is a food chain?
It shows directlinks between producers and consumers in the form of a simple line . It shows how plants and animals get their energy
What is a food web?
Shows all the connections between producers and consumers in an ecosystem in a complex way
Threats to ecosystems
Extremeweather events eg. Drought caused by globalwarming
Yellowstone national park restoration
Wolves were reintroduced
They forced the deer to avoid certain areas and vegetation in these places started to regenerate
Birds, foxes etc. all increased in population size there
The behaviour of the riverschanged
What is a biome?
A largescaleecosystem
These are defined mainly by the dominanttype of vegetation that grows there It is the distance from the equator that determines the type of vegetation that grows there Global ecosystems form broadbelts across the world
Tropical rainforest
close to the equator
Hightemperatures and heavyrainfall due to lowpressure conditions
Idealconditions for plants to grow
Overhalf of all plants and animals live here
desert
roughly 30°north and south of the equator
sub-tropicalhighpressure belts
Cloudsdon’tform , resulting in highdaytemperatures and lownighttemperatures
Plants and animals are well adapted to survive
Lowrainfall
Polar
Located at the Arctic and Antarctic
Cold airsinks at the north and southpoles, resulting in very lowtemperatures and dryconditions
Deciduous and coniferous forests
Roughly 50° - 60°north of the equator
Deciduoustreesshed their leaves in winter to retainmoisture
Coniferoustrees are cone-bearingevergreens , retaining their leaves to maximisephotosynthesis during the brief summer months
Coniferousforests are better suited to coldenvironments
The UK’s natural vegetation is deciduous forest
Temperate grassland
Roughly 30° - 40°north and south of the equator
It is found inlandaway from coasts
Experiences hot, drysummers and coldwinters
Grasses can tolerate these conditions and this land is mainly used for grazinganimals
Mediterranean
40° - 45°north of the equator
Hot,sunny and drysummers
MildWinters due to highpressurebeltsmigrating slightly north and south during the year
Vegetation includes olives, tomatoes and lemons
Savanna
Between 15° - 30°north and south of the equator
Distinctwet and dryseasons
Violentthunderstorms can occur during the wet seasons
Wildfires can occur during dry seasons
Large herds of animalsgraze on these grasslands
Tundra
From the ArcticCircle to 60° - 70°north eg. Canada
Lowlyingplants adapted to retainheat and moisture in the cold, dry and windy conditions
Fragile ecosystem
location of rainforests
Along the equator
In between the tropics
Tropical rainforest climate
The temperature is high and constant through the year
Rainfall is high because the global atmospheric circulation shows that risingair creates clouds and triggers rain
Rainfallvaries throughout the year
Plants and animals in tropical rainforests
Huge biodiversity
Home to more than half of the worlds plants and animalspecies
Tropical rainforest adaptations
Many leaves have waxydriptips that allow water to runoff them, otherwise, moss would quickly grow over the leaf’s surface, cuttingoff its light
Spidermonkeys have prehensiletails which functions as extralimbs to grabbranches, they also have long ,stronglimbs to help it climb through the rainforesttrees
Epiphytes are plants that live on branches of treeshigh up in the canopy to get sunlight , they establish aerialroots that get their nutrients from the air and water rather than soil
Sloths are slow so algaegrows on their fur for camouflage
Deforestation in Malaysia
Deforestation means that the land can be used for other profit-making enterprises like commercialfarming and the production of rubber and palmoil
The rate of deforestation in Malaysia is increasingfaster than in any tropicalcountry in the world
Causes of deforestation in Malaysia
Transmigration has led to land being cleared for newsettlements
Large companies use the land to run cattlefarms
Development of mining, farming and tourism will providejobs for people
The BakunDam that provided hydro-electricpower has flooded230 km^3 of rainforest
There Is a growingneed for land to be used to grow products - palmoil and rubber
Roadconstruction in rainforests to allow access for mining
15000hectares of land to build newsettlements
Timber is exported to developed countries which is a valuable source of income
Local impacts of deforestation in Malaysia
Soilerosion - soil takes thousands of years to form
Deforestation is happening faster in the Malaysianrainforest than any other In the world
Loss in biodiversity
Improvement in infrastructure has led to increasedtourism
HEP will provide cheapelectricity
Soil becomes infertile because the canopylayers is removed and rainfall can erode more soil
Global impacts of deforestation in Malaysia
Direct effect on globalclimates, contributing to the greenhouse effect
has an impact on the worldsoxygensupply as one third is stored in rainforests
Fires from slash and burn can get out of control,damaging wide areas of rainforest and addingcarbondioxide into the atmosphere
The rainforest is used as a worldtouristsite and is protected as a world heritage site
Medicinal plants could be lost
Why should tropical rainforests be protected?
Biodiversity - tropical rainforests contain half of all the plants and animals in the world
Climatechange - rainforests absorb and storecarbondioxide
medicine - 25% of all medicines come from rainforest plants
Resources - tropical rainforest trees provide valuablehardwoods and fruit,nuts etc.
People - indigenoustribes live in the world’s rainforests eg. The Achuarpeople
Selective logging and replanting
A more sustainable approach to logging because othertrees and plantssurvive in the logging process and can allow the forest to recover overtime
Leaves some trees for futurelogging so is sustainable
In order to access the wood, the forest will have to be cleared to make way for machinery
Conservation and education
Conservationareas can be used for education,scientificresearch and tourism
potential to discover newmedicines in plants
Costsmoney to protect these areas
Can be difficult to monitor that everyone is following the rules due to the vastareas
Some people may not be educated as to why we need to conserve them
Ecotourism
Can provide locals with jobopportunities
Localcommunities can earn extraincome from selling to tourists
Increases awareness of conservation
Deforestation would now be detrimental to the income from tourists
Locals can be exploited eg. For cheaplabour
Local people can lose their traditionalway of life
Destroyingresources to make room for ecotourism
Companies who run ecotourism earnmost of the profit
international agreements
Countries come together in peace
Raises awareness through media
Non-profitable
Cold environments
experiences temperatures at or below0°c for a longperiod of time
Coldest place on Earth = Antarctica
Characteristics of tundra regions
Wintertemperatures are lessextreme, 20°c
Summers can be warm
Precipitation can be high
In winter,soil is frozen
In summer,soilpartiallythawsclose to the surface (perma-frost)
The soil is infertile as the waterdrainsnutrients
Morefood options allow for moreanimals such as : articfox, artichare
Characteristics of polar regions
Wintertemperatures can be below-50°c
Very lowprecipitation
The soils are permanently covered by ice so soils are permanentlyfrozen
Animals include : polarbears,penguins
Some plants such as mosses are found on the fringes of the ice
What plants can be found in tundra regions?
Low-lying flowering plants
Eg. Bearberry which is adapted by its:
5-15cm off the ground to enable it to survive the strongwinds
Stems have a thickbark for stability
Waxyleaves help to retainmoisture in this dry environment
Hairystems help to retainheat
Brightredberries are eaten by birds and owls which helps to distribute the seeds