Topic 4 - Ecosystems Flashcards
What is meant by an ecosystem?
A community of biotic and abiotic factors living together and their interdependence with one another.
BIOTIC FACTORS - LIVING
eg flora and fauna
ABIOTIC FACTORS - NON LIVING
eg mineral ions, soil etc.
Outline the geographical distribution of:
- Polar regions
- Coral reefs
- Grasslands
- Tropical forests
- Hot deserts
- Polar regions; have a climate that’s v cold
Distribution - Found inside Arctic and Antarctic circles, eg Greenland and Antarctica ice sheets.
Flora: short plants in tundra, moss
Fauna: Arctic fox, Arctic wolves, Polar bears.
- Coral reefs; high sea surface temps, more than 25 deg celc.
Distributions - Found in shallow oceans in the tropics
Flora: Algae
Fauna: Parrot fish, coral polyps
GRASSLANDS; v Hot all year round
- Distribution; located in tropical Africa and midlatitude Asia.
Flora: baobab trees
Fauna: zebras
TROPICAL FORESTS; very hot
Distribution - close to equator
Flora: trees, shrubs
Fauna: Jaguars, toucans
HOT DESERTS; have a very hot climate
Distribution: located in subtropical locations at 30 degrees North and South Latitudes.
Flora - Cacti
Fauna - Meerkats, Camels
Describe the distinctive characteristics of a tropical rainforest ecosystem, including the:
- climate
- nutrient cycle
- soil profile
- water cycle
climate of a tropical rainforest;
Hot all year round; Sun’s rays hit equator at a small angle of incidence so heat is concentrated in one area. Air warms and Rises - this Cools, condenses to form clouds and convection rain.
Nutrient cycle; How are nutrients recycled through the ecosystem?
- Nutrients are stored in leaves which are a form of biomass.
- When leaves die they fall to the ground to form leaf litter.
- Decomposers break down the dead leaves and release its nutrients into the soil.
- A dense network of fibrous trees as well as plants now take up these nutrients and form new biomass.
- These nutrients are stored in the biomass.
Soil profile;
The soil of a tropical rainforest consists of 4 parts; the leaf layer, humus, deep soil layer and bed rock.
- Hot and wet climate means chemical weathering is rapid - this produces a deep layer of soil.
- Beneath this soil (up to 30m below) bedrock is found.
- Leaves from trees dropped all year round as well as twigs fall onto the soil surface - this forms a thick leaf layer.
- This is broken down to form humus which gets mixed with the soil.
Water cycle;
- Some rain from daily rainfall and convection rainfall (which occurs at night) is intercepted by the leaves of the canopy trees in the rainforest.
- This rainwater is evaporated due to the Sun and returns back to the atmosphere.
- At the same time the remaining rain not intercepted by canopy trees is absorbed by plants and released back into the atmosphere via transpiration.
^^75% rainfall is returned back into the atmosphere after rainfall.
^^Process of evaporation and transpiration together is called evapotranspiration.
Give examples of the interdependence of climate, soil, water, plants, animals and human activity in tropical rainforests.
- Plants rely on water - photosynthesis
- Indigenous tribes rely on fruit (flora) and animals (fauna) - to eat
- Plants rely on mineral ions from the soil.
etc
Identify and explain why tropical rainforests important (at least 3 reasons).
Goods;
Eg
- Rubber from rubber trees to make tyres for transport etc.
- Food - eg nuts - for consumption
- Medicines - curare is a muscle relaxant used in surgery sourced from rainforest plants.
Services
- Trees in rainforests absorb CO2 bc of photosynthesis and release O2 by respiration.
- Trees in rainforests reduce flooding of local areas bc they absorb rainwater.
- Rainforests serve as habitats for endangered species.
What are the human impacts in the tropical rainforest from activities such as:
- Logging/Deforestation
- Mineral extraction
- Agriculture
- Tourism.
Deforestation - cutting wood to make things like furniture - contributes to climate change - less CO2 absorbed etc.
- Mineral extraction; this includes mining of precious metals - and the chemical used to do this can be toxic and harmful, this is washed into streams and damages wildlife and habitats.
- Agriculture; Land is often cleared via burning and deforestation. Burning vegetation in rainforests produces CO2 and at the same time less CO2 is taken in by plants bc they’re all burnt - this process isn’t carbon neutral - so contributes to global warming (GHG ETC AND EGHE)
ALSO^^ we can talk about less biodiversity by producing only one crop, and increased chance of flooding bc less trees to absorb rain water.
- Tourism - humans may scare wildlife and cause they to abandon their young. Lack of appropriate infrastructure can damage wildlife habitats and reduce biodiversity disrupting interdependence of forest.
Check case study notes
Outline the distinctive characteristics of Antarctica and the Arctic including:
- Climate
- Features of the land and sea
- Flora
- Fauna.
(DIFFERENCES)
Climate in Antarctica is warmer than the arctic.
Artic land is covered in permafrost and is mostly flat with no mountains.
Antarctica has mountains and even a volcano called Mt Erebus.
Arctic flora: coniferous trees
Antarctic flora: Moss
Arctic fauna: Polar bears, Wales
Antarctic fauna: Penguins, seals
Describe and explain the interdependence of
- Climate
- Soil
- Water
- Plants
- Animals
- Human activity
in the Arctic polar region.
2 examples of interdependence in Arctic polar regions:
- Food chains and food webs.
- Water cycle linked to plants animals and humans.
How do food chains show interdependence?
- Flora (eg moss) are eaten by herbivores. (eg lemmings)
- Herbivores are eaten by carnivores (eg owls).
- So lemmings use snow (water) to hide away from predators carnivores.
- This shows the interdependence of flora, fauna and water in the Arctic polar region.
How does the water cycle show interdependence?
- Winter snow in the Arctic region forces caribou to migrate to South of the Arctic.
- Here they eat flora such as moss and lichen in taiga forests.
- Eventually snow melts during spring so caribou can now feed on tundra grass and mate.
- This allows for Nomadic hunter tribes in Arctic to hunt these caribou and use them as part of their traditional lifestyle.
- This shows the interdependence of water, fauna, flora, weather, climate and humans.
Explore a range of impacts of human activity on either the Antarctic or the Arctic ecosystems, such as:
- scientific research
- indigenous people
- tourism
- fishing and whaling
- mineral exploitation.
Impacts of human activity on Antarctic ecosystems.
- Scientific research of animals within Antarctic system may require damaging human activities such as whaling. The hunting of whales, whaling, has negative impacts on the Antarctic ecosystem as it reduces biodiversity. Decrease biodiversity may result in extinction of species in the Antarctic bc less interdependence and now community is no longer stable.
- Indigenous people hunting fauna such as seals/penguins to live their traditional life results in less biodiversity + LINK ^^^^^^.
- Tourism - destroys habitats when providing a place to stay - migration of animals to other environment - Antarctic has less biodiversity ^^
- Fishing and whaling for food etc = less biodiversity ^
- Mineral exploitation - harmful chemicals released into the environment when these metals are extracted. This could kill flora/fauna species = less biodiversity ^^^.
Check case study notes
What is meant by a biome?
A global scale ecosystem.
