Geography (paper 1) đź“Ť Flashcards
[Ecosystems]
Decomposers meaning
Organisms that break down organic matter (eg bacteria)
Nutrient cycling
When nutrients are passed down from one component of an ecosystem to another
Where is Epping Forest located?
North East of London
Characteristics of Epping Forest
Deciduous forest that consists of trees 100s of years old: Its leaves fall in the winter conserve energy and its leaves expand its surface area in summer to absorb more sunlight
Biomass
Energy stored in living things
Weathering
When rocks are broken down and its nutrients enter the soil
Surface runoff
When water flows on the surface washing away nutrients
Leaching
When nutrients are washed out of the soil by the rain
How do nutrients enter the soil?
Weathering and the decomposition of leaves (from leaf litter)
How do nutrients get stored as biomass?
When plants absorb nutrients from the soil using its roots
How do nutrients get stored in leaf litter?
Through precipitation and when leaves drop in autumn (from biomass)
What are 2 ways nutrients can leave an ecosystem?
Surface runoff and leaching
How are nutrients cycled around Epping Forest?
Nutrients enter the soil and then gets stored in biomass and then in leaf litter in a recurring process
Abiotic component meaning
non - living things
Examples of abiotic components
• Water • The Sun • Rocks • Soil • Air
Functions of abiotic components
• Water - helps plants to photosynthesise • Sun - provides light for growth • Rocks - provides habitats • Soil - provides nutrients • Air - helps organisms to respire
Endemic species meaning
Plants & organisms that are only found in a certain biome
[Tropical rainforests]
Reason for the distribution of tropical rainforests
• The sun is directly overhead all year therefore it’s rays are more concentrated here
• So the climate is hot and wet which provides the perfect conditions for plant growth
Describe the process of convectional rainfall
Warm air rises > the air cools > water vapour condenses > clouds and rain are formed
Why are hot deserts found either side of tropical rainforests?
Cool, dry air disperses from rainforests and starts to descend on deserts
Why are there high levels of biodiversity in tropical rainforests?
Hot and wet conditions make it optimal for plant growth
Why does soil tend to be infertile in tropical rainforests?
Nutrients in the ground are quickly taken up by the roots of many plants • Leaching also occurs
Characteristics of the emergent layer
•Trees with wide, strong buttress roots (for stability in windy conditions) • Tallest trees • Its seeds are winged to be carried by the wind
Characteristics of the canopy layer
• Home to 90% of organisms in tropical rainforests • Blocks out sunlight from layers below • Epiphytes found here (plants that grow on trees) • between 15 and 30 metres high
Characteristics of the under canopy layer
• Receives little sunlight as canopy blocks it out • Lianas (vines) climb up trees to get pollinated by insects and reproduce
Characteristics of the ground / shrub layer
• Humid and dark • Leaf litter is quickly decomposed by the humidity • soil is infertile • 2% of sunlight reaches this layer
Adaptations of drip tip leaves
Have a pointed tip to allow water to slide down the leaf in order to:
• help the water be absorbed by the roots
• prevent the leaves from breaking
Adaptations of epiphytes
• Its roots grow into the air to absorb the air’s moisture and nutrients
Adaptations of the howler monkey
• Prehensile tail supports its grip as it swings • Long limbs to swing rapidly when escaping predators
Adaptations of the tree frog
• Long tongue to catch prey • Toe pads made of mucus to stick to trees and plants
Adaptations of the three toed sloth
• Very slow moving to conserve energy • Moss grows on its fur to help the sloth camouflage to avoid being detected by predators
Biome meaning
A large ecological area
What’s a tropical rainforest?
Rainforests at the equator with a warm climate and high levels of precipitation
Biodiversity meaning
A measure of how many different species live in an ecosystem
Why is the climate of a tropical rainforest valuable globally?
• It supports the growth of a large number of trees (which grow food resources eg cocoa, sugar and banana)
• They act as a carbon sink (absorbs and stores co2 which reduces global warming)
Why is medicine processed from tropical rainforests valuable for social sustainability?
Some plants in rainforests (such as the rosy periwinkle) contain anti cancer properties used for cancer fighting drugs • This improves life expectancy
Why is water from tropical rainforests valuable?
20% of the Earth’s fresh water is found in the Amazon Basin
Deforestation meaning
When trees are cut down at a large scale
Loss of rainforest in countries around the world
Brazil has lost 89000 square miles in 17 years • Indonesia has lost 35000
Why is deforestation happening at a faster rate in some countries compared to others ?
• Space provision for urbanisation during population growth • illegal logging • Laws protecting rainforests • Economy might depend on it for income
How has the rate of deforestation in the Amazon changed?
In 2004 it was high due to commercial farming (cattle) for TNCs like Mac D • Lowest in 2012 as Brazil invests in reducing climate change and increasing tourism • Increases in 2020 as new president (Jair Bolsonaro) encourages agriculture and mining activities
Causes of deforestation in the Amazon
• Commercial farming (to make money) (accounts for 80% of deforestation)
• Subsistence farming (for survival)
• Logging
• Hydroelectric-power
• Mining
• Urbanisation
Process of how deforestation affects the soil in a rainforest
Trees are cut down -> Soil is exposed to the rain -> Nutrients are leached from the soil -> Plants are unable to regrow -> Land becomes unusable
Negative impacts of deforestation in the Amazon
• Only 240 tribes left (the indigenous losing their homes)
• Fewer trees to absorb co2
• Soil is exposed to heavy rain (leaching can occur)
• 50,000 species are becoming extinct every year
• Local climate gets drier (fewer trees to release water into the air)
• Conflict arises between loggers and the indigenous
What’s the biggest flow of nutrients out of the rainforest and why?
• Leaching • High levels of precipitation due to convectional rainfall
Sustainable rainforest management strategies
• Selective logging • Ecotourism • Conservation and education • Debt reduction • International agreements
What is selective logging and how sustainable is it?
• Only felling (cutting down) trees when they are fully grown and letting younger ones mature • Not environmentally sustainable as it can take around 50 years for trees to regrow
What is conservation and education and how sustainable is it?
• The preservation of rainforests through national parks or reserves which allows for scientific research • The environment is left untouched and isn’t negatively impacted.
What is ecotourism and how sustainable is it?
• Tourism that allows people to experience the natural environment without damaging it • It’s socially sustainable as local people are employed and environmentally sustainable
What are international agreements and how sustainable are they?
•Agreements between countries made to protect the rainforest • Not economically sustainable as the trading of valuable hardwood is restricted
What is a debt for nature swap and how sustainable is it?
• Where HICs convert LICs’ debt into a fund to protect tropical rainforests • Environmentally and economically sustainable (LICs can focus on development rather than paying debt)
What’s another way of saying an environment that’s difficult to survive in?
Hostile environment
Stakeholder meaning
Someone who has an interest in an issue
Biosphere reserve
When the central areas of a forest are protected but forms of activity are allowed on the outer zones
[Hot deserts]
Physical characteristics of a hot desert
• Hot and arid climate
• Low levels of precipitation
• Water is often found deep underground in aquifers
• Plants (Cacti) have deep tap roots to absorb water underground
• Animals are adapted to survive without food/water for a long time
• High levels of solar insolation
How is the soil eroded in hot deserts?
High wind speeds that occur during sandstorms
What do camels store in their humps to survive in a desert?
Fat
Where is the Western Desert located?
Nevada, Texas
How are cacti adapted to a hot desert environment?
• Large spikes to deter consumers from wanting to eat it
• Have spikes instead of leaves to reduces surface area and water loss (because water quickly evaporates in the hot climate)
• Stores water in stem to survive long periods without rainfall (as precipitation levels are very low in deserts)
How are bactrian camels adapted to survive in a hot desert environment?
• Humps store fat to survive long periods without food or water (because vegetation is difficult to find in an arid climate)
• Two rows of eyelashes to prevent sand from blowing into its eyes
• Thick fur all over body to reduce heat loss at night (as the temperature plummets due to a lack of clouds for humidity)
Characteristics of desert soil
Unconsolidated (-loose because there’s only a few trees to bind the soil together) and fertile (because no leaching occurs)
What conditions are required for a desert environment?
• High pressure • Cool air sinking
Irrigation meaning
Extracting water from aquifers for agriculture
Opportunities for developing hot deserts
• Mineral extraction
• Agriculture
• Energy
• Tourism
Challenges associated with developing hot deserts
• Extreme temperatures • Limited water supply • Inaccessibility
How is mineral extraction able to take place in the Western Desert?
• It’s rich in minerals like copper, uranium, zinc • Minerals are close to the surface of the ground therefore open cast mining can take place
How is agriculture able to take place in the Western Desert?
• High temperatures and water provided by irrigation makes it ideal for farming
Sources of irrigation in the Western Desert
• Water stored in aquifers can be brought to the surface by digging a well • Canals are used for large scale agriculture
How is tourism able to take place in the Western Desert?
• Many tourist attractions such as the Grand Canyon (9 million visitors a year), Lake Mead and Lake Powell (2 million) • Las Vegas attracts 37 million • Tourism is the Western Desert’s most important source of income
How is energy able to be supplied in the Western Desert?
• Sonoran Solar Project in Arizona is a new solar power plant project that will help power 100,000 homes • Hoover Dam generates hydroelectricity from Lake Mead • Fossil fuels like oil is drilled for in Arizona (25 active oil production sites also located on land owned by the Navajo people)
How do extreme temperatures present a challenge for development in the Western Desert?
• Infrastructure requires to be resistant to heat • Difficult for Native Americans to settle • Temperatures reach as high as 50C
How does inaccessibility present a challenge for development in the Western Desert?
A lack of roads make it difficult to transport resources and tourists to enter
How does a limited water supply present a challenge for development in the Western Desert?
• Makes it difficult for agriculture to take place without access to aquifers • Can lead to droughts which will inflict job losses in farming
Meaning of solar insolation
The sun’s rays are easily able to reach the ground as there’s no clouds
Types of hardwood trees in tropical rainforests
Timber trees: Teak and mahogany
How does deforestation affect water supplies?
Chemicals like mercury used in mining can poison the ecosystem and pollute the water
Positive impacts of deforestation in the Amazon
• Minerals such as gold, copper and tin from mining can be exported to make money
• Roads being built improves trade and transport (eg Trans-amazon highway)
• Hardwood is a valuable resource to export
• Almost a 1/4 of Brazil’s GDP comes from activities in the Amazon’s deforested areas
How does the Amazon have high levels of biodiversity?
It contains half of all the plants and animals in the world
Desertification meaning
When land turns into a desert because it dries out and loses its nutrients
Causes of desertification
• Population growth • Deforestation • Soil erosion • Fuelwood • Overgrazing • Over - cultivation • Drought • Climate change
How does overgrazing contribute to desertification?
The cows trample on the soil compressing the nutrients • When it rains, water cannot infiltrate the soil • Therefore water flows on the surface (surface runoff) and nutrients are leached from it
Overgrazing definition
When farmers have large herds of cattle
How does over-cultivation contribute to desertification?
Having a large number of crops would mean that more nutrients are absorbed from the soil which degrades it and makes it infertile
How does soil erosion contribute to desertification?
• Without roots binding the soil together, the soil is easily eroded by the wind (as its unconsolidated) • The soil is also exposed to heavy rainfall which means that leaching occurs
Fuelwood meaning
Burning wood for fuel eg cooking
How does fuelwood and climate change contribute to desertification?
• When wood is burned, greenhouse gases are released • This increases the temperature of the atmosphere • Causing hot areas to become even hotter and drier
What are the solutions to prevent desertification in the Sahel?
Zai and drip irrigation • Bunds • Education (cattle farming) • Afforestation • Intermediate technology • Renewable energy
What is zai and drip irrigation and how does it prevent the soil from degrading?
• They are methods for irrigating crops to maximise the moisture the soil can keep • Less water is wasted as water is only provided for the plant • This helps the soil keep its water and nutrients • It’s economically and environmentally sustainable but it can only be achieved on a small scale
What are bunds and how does it prevent the soil from being degraded?
• They are small walls built out of rocks to prevent surface runoff on slopes • It ensures the water infiltrates the soil to provide nutrients • Its a cheap solution but can’t happen on a large scale
What is afforestation and how does it prevent the soil from degrading?
It’s when trees are planted to restore degraded land • Eg Great Green Wall in the Sahel (Continuous wall of trees from east to west Africa) • The soil becomes consolidated as the root of plants bind it together • It reduces soil erosion but it can take a long time for trees to grow
How does intermediate technology prevent the soil from being degraded?
Stoves are provided for people in LICs instead of burning wood • Less trees are cut down (so less soil is exposed to rain for leaching) • Less greenhouse gases are produced (less fuelwood burned) • Reduces climate change and the loss of nutrients • Environmentally and socially sustainable (people can cook more efficiently)
[River landscapes]
Abrasion meaning
When large rocks hit and scrape against the river bed and banks
Deposition meaning
When a river drops the material it’s carrying because it loses energy
Lateral erosion meaning
When the river has lots of energy to erode the sides making the river wider
Long profile meaning
A cross sectional view of a river from source to estuary
What is the name for the sides of a river?
The river bank
What is the name for the bottom of a river?
The river bed
Vertical erosion meaning
When the river cuts down into the landscape
What is a V-shaped valley?
A steep sided valley created by vertical erosion near the source of a river
Flood plain meaning
Low lying land either side of a river which regularly floods