P1 - Unit 1B - Ecosystems and Tropical Rainforests Flashcards
What’s a natural system made up of plants, animals and the non-living environment?
An ecosystem
What are the non living elements of en ecosystem called? And what’re some examples?
Abiotic
E.g. Soil, rocks, water, sunlight
What are the living elements of en ecosystem called? And what’re some examples?
Biotic
E.g. Plants, animals, bacteria
What’s a large scale ecosystem closely related to the climate called?
Biome
What’s an organism or plant that’s able to convert energy from the sun into carbohydrates, through the process of photosynthesis?
Producer
What’s an organism that breaks down dead organic matter, such as leaves, and returns the nutrients to the soil, which can then be absorbed by plants.
Decomposer
Name two decomposers:
Bacteria and fungi
How are organisms in ecosystems linked together?
By a food chain/ food web
Name a set of processes whereby organisms extract minerals necessary for growth from soil or water, before passing them on through the food chain - and ultimately back to the soil and water.
Nutrients cycle
-recycling nutrients and energy flow
State two routes by which nutrients input an ecosystem:
- in litter layer, dissolved in rainfall
- in soil layer, from weathered bedrock
State two routes by which nutrients are lost from an ecosystem:
- in litter layer, surface loss in runoff by rainfall
- in the soil, nutrients are lost by leaching
What sits on top of the soil and contains both dead and decaying plant matter?
Litter
Name the process by which rocks are broken down and add nutrients to the soil:
Chemical weathering
Name the process by which nutrients is dissolved in rainwater and are then removed from the soil:
Leaching
What’s the name of the thin, black layer of soil made up of newly decomposed plant and animal remains?
Humus
Where are tropical rainforests located?
Between 25° north and south of the equator
Name three areas of the world where tropical rainforests can be found:
- amazon basin- South America
- Congo basin- Africa
- Indonesian islands- South east Asia
What’s the average temperature of a tropical rainforest all year round?
27°C
range between 20-28
What’s the average annual rainfall in a tropical rainforest?
2000mm, rains everyday
What type of rainfall occurs in tropical rainforests?
Convectional rainfall
How would you describe the humidity of the tropical rainforest?
High humidity
-rapid evapotranspiration
What’s the name of a tropical rainforest soil?
Latosol
List three characteristics of a tropical rainforest soil:
- deep
- infertile-leaching occurs due to high rapid rainfall
- lots of chemical weathering of bedrock
- rapid breakdown of leaf litter due to humid climate, thin layer of nutrients on the surface of the soil
Describe the growing season in a tropical rainforest:
Continuous (all year round), no definite seasons
Why does chemical weathering of the bedrock happen so quickly in a tropical rainforest?
Chemical weathering happens so quickly because of the hot, wet climate
Why does the nutrient cycle happen very rapidly in a tropical rainforest?
The hot wet climate
- average at 27°C
- 2000mm of rain per year
- no definite seasons
Where is the major store of nutrients found in a tropical rainforest? Why?
Biomass
Because in a rainforest they have the biggest store of biomass which contains nutrients and the humid climate promotes plant growth
Why is the rainforest soil described as infertile?
There’s heavy rainfall everyday and the rain leaches the nutrients out of the soil
Name the four main layers of a tropical rainforest:
Emergents
Canopy
Lower tree canopy
Shrub layer
Why do rainforest trees have buttress roots?
They stabilise the tree to allow the tree to grow tall
Increase the surface area for gas exchange
Help transport water
Why do new trees grow quickly upwards?
So that they can get the maximum amount of sunlight
What’s an example and impact of commercial cattle farming as a cause of deforestation?
Example- southern margins of Amazonia
Impact- economic
What’s an example and impact of road building as a cause of deforestation?
Example- 6000km Trans-Amazonian Highway
Impact- political, economic
What’s an example and impact of settlement and population growth as a cause of deforestation?
Example- 25million landless people migrate from drought stricken areas, new roads become ‘growth corridors’
Impact- social
What’s an example and impact of energy development as a cause of deforestation?
Example- HEP station on Tocantins river generates power for Carajás mine
Impact- economic, political
What’s an example and impact of mining(mineral extraction) as a cause of deforestation?
Example- Carajás mine in Northern Amazonia Worlds largest source of iron ore
Impact- economic
What’s an example and impact of logging as a cause of deforestation?
Example- Hardwoods(such as mahogany, teak, rosewood), Japan uses 11 million cubic meters of Equatorial hardwoods per year
Impact- economic
What’s an example and impact of commercial arable farming as a cause of deforestation?
Example- Soya grown in Amazonia is used to feed UK chickens
Impacts- economic
What’s an example and impact of subsistence farming as a cause of deforestation?
Example- Slash and burn cleared small areas by indigenous tribes
Impact- social
What’s the term for the absolute clearance of all trees from an area of forest?
Clear felling
What’s the term for the cutting down of selected trees, leaving most of the trees intact?
Selective cutting
List five local impacts of deforestation:
- decline of indigenous tribes
- soil erosion
- river pollution
- local climate change
- conflicts
List two global impacts of deforestation:
- more carbon dioxide, global warming
- less biodiversity
Which economic activity most threatens the indigenous people and why?
Logging, because the indigenous people lose there place to live
How does deforestation cause river pollution?
Mining
Mercury is used to mine gold from the ground, this mercury is then washed into rivers, which poisons fish and people in nearby towns
How does deforestation cause the soil to become infertile?
The nutrient cycle is disrupted, heavy rain leaches the soil of its nutrients
What’s the difference between goods and the services of a tropical rainforest ecosystem?
Goods are things obtained directly from the rainforest.
Services are benefits that the rainforest can offer to people and the environment.
List three goods that can be obtained from a tropical rainforest:
- timber
- native fruits and nuts
- wild meat, fish
List three services supplied by tropical rainforests:
- wildlife habitat-biodiversity
- air purification-absorbs carbon dioxide
- employment opportunities-ecotourism
What’s the term for development that preserves future resources, standards of living and the needs of future generations?
Sustainable
On what two levels does rainforest management occur?
- local level
- international level
What does FSC stand for?, is it an example of international or local management?
FSC- Forest Stewardship Council
-international management
List three international management strategies:
- intergovernmental agreements on hardwoods(FSC)
- debt reduction
- conservation and education by NGOs
What term means that natural resources can still be used, but only if used sustainably?
Conservation
What term means that the environment should be untouched and humans should not interfere, so ecosystems can find there own balance?
Protection
List six local management strategies:
- ecotourism
- conservation and education
- selective logging
- agroforestry
- stopping illegal logging
- replanting
Give a named example of an ecotourism scheme in the Amazon rainforest:
Tambopata lodge - Peruvian Amazon
What’s the total weight of all biotic organisms per unit area?
Biomass
What’s an example of a small scale U.K. ecosystem?
Epping Forest in North East London
How are plants adapted to the tropical climate?
- drip tips- to allow excess rain water to run off
- waxy leaves- to allow water to flow off, and to reduce evaporation
- leaf angling- so the plant avoids shading its own leaves
- stilt and buttress roots- to support the tree so it can grow tall above the canopy to get light
What are examples of global ecosystems?
- Grassland
- Tundra
- Temperate Deciduous Forest
- Tropical Rainforest
- Polar
- Hot Desert
What are the characteristic of a grassland ecosystem?
- SAVANNAH GRASSLANDS (found between the tropics), distinct dry and wet seasons, average rainfall is relatively low, grass with a few trees for vegetation
- TEMPERATE GRASSLANDS (found at higher latitudes), more variation in temperature and less rainfall, no trees just grasses
What are the characteristics of a tundra ecosystem?
- Found at higher latitudes
- Winters are very cold, summers are brief and there is little rainfall
- hardly any trees, have mosses, grasses and low shrubs for vegetation
- there’s a layer of permafrost
What are the characteristics of a tropical rainforest ecosystem?
- Found around the equator, between the tropics
- Hot and wet all year round
- have lush forest, with dense canopies forming distinct layers
What are the characteristics of a temperate deciduous forest ecosystem?
- found mainly in the mid latitudes
- have four distinct seasons
- summers are warm and winters are mild
- rainfall all year round
- deciduous trees lose their leaves in the winter
What are the characteristics of a Polar ecosystem?
- found around the north and south poles
- cold, icy and dry
- not much grows, they remain dark for several months each year so the growing season is very short
What are the characteristics of a Hot Desert ecosystem?
- found 15° and 35° north and south of the equator
- there’s little rainfall, hot in the day and cold at night
- shrubs and cacti are sparsely distributed in the sandy soil
What are features of plants in tropical rainforests?
- evergreen (to take advantage of the continual growing season)
- trees are very tall and vegetation cover is dense (very little light reaches the forest floor)
- lots of epiphytes (plants that grow on other living plants)
What are features of animals in tropical rainforests?
- contain more animal species than any other ecosystem in the world
- brightly coloured and make lots of noise
- examples: gorillas, jaguars, anacondas, tree frogs, sloths
What are features of people in tropical rainforests?
- people who have adapted to life there over many generations
- make a living by hunting and fishing and gathering nuts and berries and growing plants in small garden plots
What type of ecosystem is the rainforest?
an interdependent ecosystem
How are plants in the rainforest adapted?
- tall trees competing for sunlight have buttress roots to support their trunks
- plants have thick waxy leaves with pointed tips (drip tips channel the water so it runs off, so the weight of the water doesn’t damage the plant)
- trees have smooth, thin bark as there is no need for protection from cold temperatures & increases runoff
How are animals in the rainforest adapted?
- many animals live their entire life in the canopy and so have strong limbs
- some animals have flaps of skin to allow them to glide between trees
- camouflage
- some are nocturnal, so they are active when it is cooler at night (helps them to save energy)
- some are adapted to low light levels on the forest floor, strong sense of hearing and smell
- many rainforest animals can swim, to cross river channels
what is biodiversity?
The variety of organisms living in a specific area
How is population pressure a reason for deforestation?
as the population in an areas increases, trees are cleared to make land for new settlements
How is energy development a reason for deforestation?
building dams to generate hydro-electric power floods large areas of forest
What are the environmental impacts of deforestation?
- soil erosion occurs because of the lack of trees so landslides and flooding can also occur
- without trees to intercept and roots to absorb rainfall, more water reaches the soil (reducing the fertility as leaching occurs)
- trees remove carbon dioxide from the atmosphere, burning trees also creates carbon dioxide (all adds to the greenhouse effect)
What are the economic impacts of deforestation?
- logging, farming and mining creates jobs
- money is made from selling timber, mining and commercial farming
- long term deforestation can destroy the resources that countries depend on
- livelihoods of some local people are destroyed
How is the rate of deforestation changing?
- rate of deforestation is very high
- globally the rate seems to be slowing down, but their are still hotspots of deforestation (e.g. Borneo)
What are the causes of deforestation in the amazon?
ORDER FROM MOST SIGNIFICANT CAUSE TO LEAST
- commercial cattle ranching
- small-scale subsistence farming
- commercial farming (soy, rice, corn, sugar)
- logging, including lots of illegal logging
- mineral extraction, road building, energy developments and building new settlements
What are the environmental impacts of deforestation in the Amazon?
- Amazon stores 100 billion tonnes of carbon, deforestation will release this causing global warming
- Brazil is loosing 55 million tonnes of topsoil every year because of soil erosion caused by soy farming
What are the economic impacts of deforestation in the Amazon?
- brough wealth to coutries that were extremely poor
- farming makes a lot of money for countries in the rainforest (Brazil made $7billion from cattle in 2008)
- mining industry creates jobs for local people (In peru 3500 people are employed in the industry)
- logging contributes hugely to Brazil’s economy
Why is it important to protect the rainforest?
- to preserve its biodiversity
- many products including rubber, coffee, chocolate and medicines
- reduces the enhanced greenhouse effect
- they help regulate climate and the water cycle
What are some strategies to sustainable manage tropical rainforests?
selective logging replanting ecotourism international hardwood agreements education reducing debt conservation
How can selective logging be a strategy to sustainably manage tropical rainforests?
- only felling some trees, less damaging because the main body of the rainforest remains, so it can regenerate naturally
- least damaging forms are horse logging and helicopter logging, rather than using huge trucks
How can replanting be a strategy to sustainably manage tropical rainforests?
- new trees being planted to replace the cut down ones
- means there will be trees for people to use in the future
- same types of tree are planted as were cut down, to maintain the variety of trees
- in some countries there are laws making logging companies replant trees when they clear an area
How can ecotourism be a strategy to sustainably manage tropical rainforests?
TOURISM WHICH MINIMISES THE DAMAGE TO THE ENVIRONMENT AND BENEFITS LOCAL PEOPLE
- only a small number of people in an area at one time
- provides a source of income for local people, so they don’t have to log or farm to make money (less trees cut down)
- been very successful in Costa Rica with it being the largest source of income for the country and over 20% of their country is protected from investment
How can international hardwood agreements be a strategy to sustainably manage tropical rainforests?
HARDWOOD IS A TERM FOR CERTAIN TREE SPECIES (e.g. mahogany, teak) - used for furniture
-high demand for hardwoods from rich countries means that some of these trees are becoming rare, these agreements promote sustainable management
-Forest Stewardship Council (an NGO), mark sustainably-sourced timber products with their logo so consumers can choose their products with knowledge of their origins
How can education be a strategy to sustainably manage tropical rainforests?
- education of the international community about the impact of deforestation (encouraging people to buy products that are certified from sustainable sources)
- some local people don’t know the environmental impacts of deforestation, so educating them can reduce the damage and show them other ways to make an income
How can reducing debt be a strategy to sustainably manage tropical rainforests?
- lots of tropical rainforests are in LICs
- LICs often borrow money from HICs to fund development schemes, this money then has to paid back with interest (they normally allow logging, farming, mining to pay back the debt)
- reducing debt means LICs don’t need to exploit their forest
- conservation swaps are an effective way to exchange debt for money being spent directly on conservation
How can conservation be a strategy to sustainably manage tropical rainforests?
- many countries have national parks and nature reserves in rainforests (however lack of funds can make this difficult to police)
- some countries set up funds which overseas governments and businesses can invest in, this money can then be used to enforce restrictions on damaging activities
