Ecosystems Flashcards
What is an ecosystem?
a community of plants and animals that interact with eachother and their physical environment
What is a biome?
an ecosystem on a global scale - creates the biosphere (layer of living things on our planet)
What is the climate of tundra biomes?
- below 0°C for most of the year
- only reach 10°C in summer
- low precipitation (often below 250mm)
What is the climate of boreal forest biomes?
- warm summers 16-30°C
- cold winters below 0°C
- less than 500mm (which usually falls in the summer)
What is the climate of temperate forest biomes?
- warm summers 18 °C
- cool winters 5 °C
- precipitation all year 1000mm
What is the climate of temperate grassland biomes?
- hot in summer 25 °C
- v cold in winter -40 °C
- 500-900mm of rainfall - most in late spring or summer
What is the climate of desert biomes?
- v hot all year 30+ °C
- low rainfall less than 250mm
What is the climate of tropical grassland biomes?
- hot all year 25-35 °C
- 500-1000mm of rainfall per year
- dry season
What is the climate of tropical rainforest biomes?
- hot all year 27-30 °C
- wet all year 2000-3000mm
What is the vegetation of tundra biomes?
very few plants - mostly Lichens and Mosses - trees are rare and stunted
What is the vegetation of boreal forest biomes?
coniferous trees with needles to survive the cold and reduce water loss
What is the vegetation of temperate forest biomes?
deciduous trees that drop leaves in autumn
What is the vegetation of temperate grassland biomes?
grasslands with v few shrubs/trees
What is the vegetation of desert biomes?
plants have storing features (succulence) and spines instead of leaves and extensive root systems
What is the vegetation of tropical grassland biomes?
tall grasses with scattered, drought adapted trees and shrubs
What is the vegetation of tropical rainforest biomes?
huge variety of broadleaved plants - trees dominate with other plants competing for light
What is the distribution of tundra biomes?
- within the arctic circle
- high latitude
What is the distribution of boreal biomes?
- at higher latitudes
- canada and russia
What is the distribution of temperate forest biomes?
- mid-latitude
- 45º north of equator
- e.g. Europe, east USA
What is the distribution of tropical grassland biomes?
- mostly south of the equator
- low latitudes, mostly within tropic of capricorn
- e.g. South Africa
What is the distribution of temperate grassland biomes?
- found around 45º n-s of equator just above tropics
- higher latitudes
e. g. Australia
What is the distribution of tropical rainforest biomes?
- within the tropics of capricorn and cancer 23.5º n-s
- low latitudes
- usually at coastlines (prevailing winds bring moisture)
- south america e.g. amazon rainforest, Brazil and SE Asia
What is the distribution of desert biomes?
- low latitudes
- close to equator
- within tropics
- e.g. Sahara Desert, North Africa
What climatic factors affect biome distribution? (3)
- temperature (lower at higher latitudes - e.g. boreal forest is colder than tropical rainforest)
- precipitation (influenced by global circulation system e.g. deserts have low precipitation due to descending dry air)
- sunshine hours (eg lower sunshine hours in tundra means less sunlight for plants to photosynthesise than in tropical rainforest)
What climatic factors affect biome distribution? (2)
- rock and soil type (leads to different vegetation in the same ecosystem e.g. NW australia poor sandy soul means shorter grass than in other tropical grasslands)
- altitude differences (leads to different plants growing within the same ecosystems e.g. higher altitudes mean lower temp - lowland forests and mangroves grow - at cloud level?? moist cloud forests occur??)
What is a climatic factor?
any factor linked with the earth’s climatic system which is driven by the sun’s energy - large scale (e.g. latitude)
What is a local factor?
any factor to do with a local area - small scale (e.g. soul type)
What is a good?
a tangible object you can take to use from an ecosystem/biome (e.g. wood/minerals)
What is a service?
something a biome does which automatically benefits us (e.g. preventing flooding/regulating the atmosphere)
What are the services of a tropical rainforest?
- photosynthesis-regulating atmosphere
- maintaining soil health
- flood prevention
Which resources do people obtain from the biosphere?
- food
- medicine
- fuel resources
- building materials
What are the three main overextracted goods in the biosphere?
- water - (e.g. Hamoum Wetlands - Iran dried up from over abstraction, population growth and dam building)
- biofuels/energy - (e.g. Malaysia decline in orangoutangs for palm oil extraction in their trees and fewer crops can be grown for local people as they are used for biofuels)
- mineral resources - (e.g. mountain top removal destroys mountains)
Which foods are provided from the biosphere?
- fish and meat
- sustainable harvests e.g. fruits/nuts
- natural vegetation is replaced by crops
Which medicines are commonly obtained from the biosphere?
- poppies for morphine
- aloe plant soothes skin conditions
- lichens stop blood loss from cuts
- vitamin c from oranges
Which fuel resources are commonly obtained from the biosphere?
- animal dung dried and burned
- trees and shrubs
- fermenting crops like sugar cane produces bioethanol
Which building materials are commonly obtained from the biosphere?
- straw for roofing and insulation
- timber
- animal dung, straw and clay mix for bricks
What is the nutrient cycle?
- fauna/flora die and fall onto the ground
- the material is decomposed by microorganisms
- the decomposed material fertilises soil, increasing amount of nutrients and so more vegetation grows
What does the Gersmehl model show?
the nutrient cycle in an ecosystem with biomass, litter and soil in little circles
What are the ecosystems of the UK? (5)
- moorlands
- heaths
- woodlands
- wetlands
- marine areas
What are the characteristics and distribution of wetland ecosystems in the UK?
- many no longer exist as they are often drained and used for farming
- have water logged soils low in nutrients, acting as a vital habitat for many species e.g. bog moss and bittern birds
- mostly located in Scotland and East Anglia
What are the characteristics and distribution of heathland ecosystems in the UK?
- 95,000 hectares in lowland areas scattered around the UK
- some are dry//sandy where as some are marshy
- distinctive species e.g. ladybird spider
What are the characteristics and distribution of moorland ecosystems in the UK?
- covers 350,000 hectares in England and Wales, largest area in Scotland
- upland areas
- too high for arable farming
- rough grassland, peat bogs and low growing plants found
- heather dominates and large areas used for grouse shooting
What are the characteristics and distribution of marine ecosystems in the UK?
- found in our seas and can be divided into two sections;
- inshore
- offshore
- make up area around UK which is 3.5 times the landmass
What are the characteristics and distribution of woodland ecosystems in the UK?
- makes up 12% of UK, 5% is ancient forest and 80% is less than 100 years old
- mostly deciduous in England but monoculture non-native plantations are found in Scotland
In what ways are marine ecosystems important to the UK? (3)
- for tourism
- for fishing
- for energy
Why are marine ecosystems important for tourism in the UK?
- 250 million people visit coastlines per year
- 200,000 jobs have been created
- provides £3 billion to the UK economy
Why are marine ecosystems important for fishing in the UK?
- 12,000 fisherman use the ecosystem to capture fish
2. UK is the 7th largest fishing fleet in the EU
Why are marine ecosystems important for energy in the UK?
- 24 billion barrels of oil are being extracted from the North Sea - enough for 30 years of production
- 450,000 people employed in the energy industry
- 175 turbines on London Array - worlds largest offshore wind farm
How have marine ecosystems been degraded?
- development of coastlines leads to destruction of plant and wildlife habitats e.g. salt marshes
- climate change allows new species to move into new areas altering the food chains
- overfishing of fish species e.g. cod impacts wider ecosystem and damages food chain
- fertilisers by farmers lead to eutrophication from chemicals reaching the sea
What are the biotic characteristics of the tropical rainforest?
indigenous tribes - hunt animals for food, have small-scale farming and spread seeds when eating fruit
What are the biotic characteristics of the deciduous woodland?
humans - shape the woodland by walking, cycling, horse-riding and picnics
What are the abiotic characteristics of the tropical rainforest? (2)
- fast leaching means soil is low in nutrients - heavy rainfall seeps into the soil taking nutrients/minerals with it as it moves downwards
- chemical weathering is common in bedrock as warm, moist conditions
What are the abiotic characteristics of the deciduous woodland? (4)
- thick later of leaf fall each year creates deep, fertile soil
- slow leaching - nutrients move slowly through the soil
- plants in herb layer blossom before larger plants grow their leaves (blocking sunlight)
- bogs/ponds provide habitats for plant and animal species range
What is the Gersmehl model like for a tropical rainforest ecosystem?
biomass is the largest store - nutrients are recycled quickly because of year-round plans growth and rapid decomposition of dead matter due to warm, wet conditions
What is the Gersmehl model like for a deciduous woodland ecosystem?
they are similar sizes
Why do tropical rainforests have high biodiversity?
- believed to be the oldest ecosystem so species have been evolving for a long time
- complex layered structure creates a range of habitats
- hot, wet climate all year with no seasons
- long hours of sunlight with warm temperatures are ideal for photosynthesis
Why do tropical rainforests have a moderate biodiversity, lower than tropical rainforests? (5)
- lower food production levels in winter
- smaller size ecosystem so less space for plant and animal species
- higher latitude - lower temp and fewer sunlight hours (not as efficient for photosynthesis or food productions for animals)
- rainfall all year with distinct seasons leading to different adaptations by species
- four layers create a range of habitats
How are animals adapted to live in the tropical rainforest? (2)
- strong limbs e.g. monkeys have evolved gripping hands and feet and long tails to balance, to find food 30-40m high where the berries are
- camouflaged to match surroundings e.g. uroplatus geckos in Madagascar or animals in herb layer camouflaged to hide in shadows (2% sunlight)
How are plants adapted to live in the tropical rainforest? (5)
- emergent trees have adapted to grow 40m to reach above the canopy to get more light for photosynthesis
- trees are deciduous so drop leaves in drier periods to conserve water
- lianas climb trees to reach light
- plants have thick, waxy leaves with drip-tips so water runs off them to prevent mould/rotting
- buttress roots have developed which are stable and only reach the top layer of soil where the nutrients are found
How are animals adapted to live in the deciduous woodland? (4)
- must adapt to harsh winters
- birds migrate from the UK to warmer conditions in winter
- squirrels store food for winter
- some hibernate e.g. hedgehogs
How are plants adapted to live in the deciduous woodland? (4)
- deciduous trees drop leaves to reduce transpiration and conserve water
- trees spread branches for greater access to sunlight
- broad, thin leaves on plants to absorb maximum sunlight in the summer
- § trees have large, deep root systems for stability and to reach nutrients and ground water
What goods are provided by tropical rainforest ecosystems? (3)
- source of food e.g. fruits and nuts for indigenous tribes
- diverse range of plant species which are key ingredients for drugs
- timber for manufacture, construction and fuel
What services are provided by tropical rainforest ecosystems? (3)
- acts as a carbon store - takes in 2 billion tonnes of CO2 per year
- source of revenue as a popular tourist attraction
- home to many indigenous tribes
What goods are provided by deciduous woodland ecosystems? (3)
- wood (used for fuel in wood-burning stoves)
- wood pellets (most common biomass in power stations to burn biomass)
- contribute to 13 million tonnes of timber used each year in UK construction
What services are provided by deciduous woodland ecosystems? (3)
- act as carbon store (UK woodlands take 1 million tonnes of carbon per year)
- protect rare animal and plant species (e.g. rare native bluebells)
- used for cycling, walking etc (e.g. in the New Forest)
What are the three elements of tropical rainforests and deciduous woodlands that climate change is impacting?
- structure
- functioning
- biodiversity
How does climate change threaten the structure of tropical rainforests?
long periods of drier conditions slows down the process of decomposition, reducing the biomass store
How does climate change threaten the structure of deciduous woodlands?
rising temps and drier conditions increase risk of forest fires - significant damage to plants and animals
How does climate change threaten the functioning of tropical rainforests?
longer periods of drier conditions stop “cloud functioning” - the process that provides water for the ecosystem
How does climate change threaten the functioning of deciduous woodlands?
increased drought threatens survival of trees because they become vulnerable to disease
How does climate change threaten the biodiversity of tropical rainforests?
changes in climatic conditions (e.g. less rainfall) threaten survival of species, leading to invasion of non-rainforest species that are more tolerant of the changing conditions
How does climate change threaten the biodiversity of deciduous woodlands?
milder winters could mean pests survive causing rise in disease
What are the main causes of deforestation in tropical rainforests? (3)
- resource extraction
- conversion to agriculture
- population pressure
How does resource extraction cause deforestation in tropical rainforests?
- mining - rising demand/prices for minerals e.g. iron ore, brazil
- illegal logging - high demand for timber in the western world
- road building - to transport resources like iron ore and timber often without proper controls
How does conversion to agriculture cause deforestation in tropical rainforests?
- oil palm plantations - demand high for food, cosmetics and as biofuel
- cattle ranching - biggest cause of deforestation in the Amazon - needs vast areas of land
- subsistence agriculture - land cleared to grow crops quickly loses nutrients so farmers clear more
How does population pressure cause deforestation in tropical rainforests?
- demand for housing and agriculture e.g. Madagascar population 4 - 20.7 million in 1950-2010
What are the main causes of deforestation in deciduous woodlands? (3)
- urbanisation/population growth
- timber extraction
- agricultural change
How has urbanisation and population growth caused deforestation in deciduous woodlands?
- land to build new homes (pressure on green belt sites where houses can fetch higher prices
- higher car ownership (demand for wider roads to ease congestion)
How has timber extraction caused deforestation in deciduous woodlands?
- replanting with conifers (38% of deciduous woodland cleated in 20th century)
- conifers more economic (faster growing, easier to manage, quicker return)
- cost of conifer plantations (dense canopy blocks light, monoculture, non-native species, reduces biodiversity)
How has agricultural change caused deforestation in deciduous woodlands?
- pesticide damage (woods often border farmland so chemicals sprayed could damage trees and wildlife)
- need for farmland (most land cleared centuries ago so rising demand affects ancient woodland)
Why does the Amazon Rainforest require sustainable management? (3)
- consists of 1/3 of the planet’s remaining tropical rainforest
- provides resources for people locally and worldwide - food, water, timber, medicines
- home to diverse range of plants and animals with over 1300 bird and 40,000 plant species
How have government policies helped to manage the Amazon Rainforest more sustainably?
- National Forests belong to the state - but government can grant timber companies concessions to manage certain areas
- Brazil - 31 national forests cover 16 million hectares
- biodiversity survey must be carries out before logging to establish the areas in need of protection
How has commodity value helped to manage the Amazon Rainforest more sustainably?
- timber firms realise that undamaged forest is a commercial asset and they can yield sustainable income
- sustainable management or reduced-impact logging can be more profitable than clear all methods of timber extraction
- reduced-impact logging is 12% cheaper than conventional logging
How has ecotourism helped to manage the Amazon Rainforest more sustainably?
- construction of visitor centres are used to educate local people and tourists about the importance of conservation
- provides alternative form of employment that doesn’t involve removing trees
What are the positives of using Reduced-Impact Logging?
- mature trees are selected to cut down
- “seed” trees are left to help quicker regrowth
- direction of falling trees is calculated to reduce damage
- less fragmentation and quicker regeneration
What is bad about Conventional Logging?
- the rainforest becomes fragmented and species become endangered
- for every tree cut down, 10-20 others are damaged
Why does The New Forest require sustainable management? (4)
- National park is a popular tourist attraction - over 15 million a year contribute to local economy
- Movement of visitors cause litter, erosion and air pollution from traffic
- Softwood and hardwood timber being extracted for commercial use
- 40% of the woodland privately owned and often unmanaged
What sustainable management is used on the New Forest?
- New trees planted
- NPA raised awareness (posters, leaflets)
- Careful management by NPA (dedicated walking and cycling routes in more fragile areas)
- The Green Leaf Tourism Scheme (promote use of local products)
- Work restricted (April-August minimises disturbance to nesting birds)
- Pesticide use limited
- Sustainable transport schemes (e.g. bike electric vehicle hire) to reduce congestion/pollution
- Landowners funded to plant native tree species by NPA
- Tree felling controlled (some left, older trees felled and left to rot)
What does the NPA stand for?
National Park Authority - careful management of the New Forest with dedicated walking and cycling routes in more fragile areas, awareness raising (leaflets and posters on sustainability importance), fund landowners to plant native tree species