Geography Paper 3 Flashcards
What is the biosphere
The biosphere is the parts of the atmosphere that are occupied by living organisms
How does the biosphere provide food for native people
-Many indigenous people rely on plants and animals for their food. Some indigenous people forage and pick wild fruits, vegetables and nuts from the biosphere. Some inidgenous people also hunt and trap animals and fish from the biosphere
How does the biosphere provide medicine for people
Many people rely on the biosphere for medicine. Lots of plants have medicinal properties and are used to cure illnesses and keep people healthy.
-plant species in the tropical forests have been used to create over 7000 different drugs e.g quinine from the cinchona tree is used to cure malaria
How does the biosphere provide building materials for people
- Trees and plants are often used as building materials for people e.g pine from the tiaga forest is used to make furniture and build houses
- Sap for trees is used as glue or to make houses waterproof
- Reeds and straw is used as roofs and plant fibres are used to make rope
How does the biosphere provide feul for indigenous people
Indigenous people rely on the biosphere for feul for cooking and keepinh warm. Indigenous people use Wood,moss,dried grass and dried animal dung for fuel. In areas with little vegetation people may also use animal fat for fuel
Why is the biosphere being exploited for energy
The biosphere is being exploited for energy to meet increasing demand for energy. Demand for energy is increasing due to population growth and increased use of electronic devices
How is increased demand for energy affecting the biosphere
- Large areas of forests are cleared to make space for the growing of crops to make biofeuls
- Drilling for oil and gas in the tundra is damaging the biosphere as pipelines are melting the permafrost
- Some areas of tropical forests are being flooded by the building of HEP dams
Why is demand for water increasing
Demand for water is increasing because of increases in global population. People are using water for irrigation farmland and washing.
How is increased demand for water damaging the environment
Increased demand for water resources has led to the over exploitation of water in arid areas such as the sahara dessert. This has damaged the biosphere as it means there is not enough in these areas for plants and animals to survive
What are minerals used for and how is demand for them changing
Minerals such as iron and gold are used in building,scientific instruments and in electrical appliances and demand for them is increasing
How is demand for minerals causing damage to the biosphere
Minerals are extracted by mining. Mining causes deforestation and releases toxic chemicals into water sources ,killing animals. Mining also removes large areas of the surface
How does the biosphere help to control the different proportions of gases in the atmosphere
The biosphere helps to control different proportions of gases in the atmosphere as
- Plants take in crabon dioxide and release oxygen during photosynthesis
- Animals give out carbon dioxide and take in oxygen during respiration
Why is mantaining the proportion of gases in the atmosphere important
Maintaining the proportion of gases in the atmosphere is important as :
- Increased levels of Co2 can lead to global warming
- Increased levels of Co2 can make oceans more acidic affecting the organisms that live there
- Too little co2 makes the earth too cool to sustain human life
How do plants and animals help to maintain soil structure and nutrients
- Plants roots and animals spread nutrients throughout the soil . This helps to maintain soil structure and fertility, whivh allows plants to grow there
- Plants roots also hold the soil together and maintain soil structure. This prevents the soil being eroded by wind and rain .
- Vegetation also intercepts rainfall before it hits the ground . This helps to prevent leaching -Where nutrients are washed by rainfall out of the reach of plants
How do plants regulate the global water cycle
- Plants regulate the global water cycle by taking in water. This means less reaches rivers and lakes meaning less flooding
- Plants also store water and release it very slowly back into the atmosphere reducing the risk of drought
What is the main overaching factor increasing demand for resources
-Global population growth is the main factor increasing demand for resources. The UN have predicted that in the highest prediction the global population will reach 14 billion by the end of the century
How can increasing wealth affect resource consumption and increase demand for resources
- Economic development is leading to more people getting wealthier
- Wealtheir people have more disposible income this affects their resource consuption
- They have more money to spend on food so often buy more than they need
- They can afford fridges, TVs and cars all of which use lots of energy and take alot of energy to produce
- They can buy more water intense utilities e.g dishwashers so use more water resources
Why does urbanisation lead to increased demand for resources
- Urbanisation is the proportion of a countries population that are living in urban areas
- Urbanisation tends to increase demand for resources because:Urban areas tend to be more resource intense than rural areas e.g street lamps and neon signs require energy to run and fountains require water
- Food and water also has to be transported long distances to reach urban areas to match increased demand - this increases energy usage
How does industrialisation lead to increased demand for resources
- Industrialisation is the process of a countries main economic activity shifting from primary production to secondary production
- Industrialisation is increasing demand for resources as manufacting and processes requires lots of energy to heat and shape things such as cars and also requires lots of water to cool components
What was Malthus’ theory
- Malthus believed that population was increasing faster than supply of resources and eventually there would be too many people for the resources avaliable.
- He believed that once this point had come ,people would be killed by catasrophes such as famine,illness and war and population would be reduced back to a level that resources could support
- This point is called point of catasropher
What was Boserups theory
- Ester Boserup theorised that however big the worlds population grew ,people would always produce sufficient resources to meet their needs
- She thought if resource supply became limited then people would find new ways to increase production (e.g technological advances) in order to avoid hardship
How do foodchains work
- Foodchains always start with producers. Producers make their own food using energy from the sun.
- Producers are then eaten by primary consumers who are are eaten by secondary consumers who are eaten by tertiary consumers
- All these organisms eventually die and are broken down by decomposers
How are elements of the tiaga ecosystem interdependent upon one and other
- Plants gain their nutrients from the soil, and provide animals that eat them with nutrients. In turn, the animals help spread the plants seeds through their dung . Helping the plants to reproduce
- Herbivores rely on plants such as mosses for food, they will migrate to areas where there are more plants so they can survive .
- The cold climate of the tiaga forest means that plants grow very slowly and decompose very slowly. This means there arent many nutrients in the soil, again affecting plant growth
- In summer the trees absorb heat and provide shade to plants on the floor. This means that the permafrost doesnt thaw
What is the structure of tiaga forests
Tiaga forests have much simpler structures than tropical rainforests.
- There are lots of conifer trees growing quite close together.
- There are not many plants on the forest floor because of the poor soil and the dense canopy that doesnt let much light through. Mosses and lichens are the main type of plant that tends to grow
How are the conifer trees in the tiaga forest adapted to the cool,dry climate
- Conifer trees are evergreen so they can make best use of avaliable light
- Conifer trees have needles instead of flat leaves. This reduces the water loss from heavy winds because of the reduced surface area
- Conifer trees are cone shaped so that heavy snowfall during winter can slide straight off branches without breaking them. The branches are also bendy so dont snap
How are animals adapted to survive the tiaga conditions
- Many larger mammals are migratory e.g caribou. They travel large distances of forest to find food to survive
- Many animals are well insulated against the winter cold e.g wolves have thick fur
- Many animals hiberate to help them conserve energy and survive the winter e.g brown bears
- Many animals e.g snowshoe hares have white coates during winter this helps to be camoflagued with the winter snow so that they can evade predators. Some predators are also camflagued with the surroundings to help them sneak up on prey
Why are there so few nutrients in tiaga forests
- There are so few nutrients in tiaga forests because few nutrients are added through precipitation and weathering. Lots of nutrients that are added are lost to runoff and leaching
- There are also few nutrients because the cold , dry climate means nutrient cycling is much slower
Where are most of the nutrients stored in tiaga forests
Most of the nutrients are stored as dead organic material (litter) in the tiaga forest. E.g as fallen needles on the forest floor
Why is nutrient cycling so slow
- The trees are evergreen and so drop their needles all year round
- Despite the constant leaf fall, low temperatures means that it takes a long time for litter to decompose and be added back to the soil.
- Conditions are too harsh for many decomposers so the soil remains of low fertility
- Plants grow very slowly because of cold climate so the rate of transfer of nutrients from soil to plants is slow
What is one reason why biodiversity is so low in the tiaga forest
One reason why biodiversity is so low is because the land was much colder and covered by ice 15,000 years ago. The species have had relativley little time to adapt to the current climate
What is another reason why the tiaga forest is so low in biodiversity
The tiaga forest is so low in biodiversity because the simple structure of the forest means there arent as many habitats. This means there arent as many ecological niches to fill and not as many species.
What is another reason why biodiversity is much lower in tiaga forests
-Biodiversity is much lower in tiaga forests because tiaga forests are much less productive than tropical rainforests (plants grow more slowly so produce less biomass) and nutrients are returned to the soil slowly because of the cold climate. The growing season is also much shorter. All of this means there is a shortage of good which makes it harder to survive.
What are some threats to the tiaga forests
Pulp and paper production-felled trees are mashed to make pulp which is used to make paper
Fossil fuels-trees are cleared to extract oil and gas from the ground
Mineral extraction-tiaga forests are very rich in minerals. Lots of trees are cleared to make way for mines and access roads
HEP-dams that are built on rivers in the tiaga forest to generate hydroelctric power flood large areas of land
Softwood logging-Trees are cut down to make furniture and housing
What is an example of a fossil fuel being extracted
An example of something being extracted is tar sand.Tar sand is earth containing a thick,black oil that can be turned into fossil fuels. Tar sands are found beneath the taiga forest
-Extraction of tar sands can involve open pit mining or strip mining(where strips of land are dug up to get to the sand below). These methods are causing large scale deforestatiob
How is acid rain formed ?
-Acid rain is formed when gases such as sulfur dioxide and nitrogous oxides ,from burning fossil fuels,dissolve in water in the atmosphere and form . When it rains or snows, these acids are deposited on plants and soil.
What affect does this acid rain have on plants and animals in the taiga
- acid rain damages plants leaves which makes it harder for them to deal with the cold
- Acid rain makes soil too acidic to support growth
- Acid rain kills organisms living in lakes and streams
How are pests and diseases posing a threat to the taiga forests
- Pests and diseases cause damage to organims
- Many pests and diseases are specific to one species e.g the spruce bark beetles only attack spruce trees. As there is often only one species in an area of taiga forest pests and diseases can spread quickly and cause alot of damage.
Why is the issue of pests and diseases becoming worse
The issue of pests and diseases is becoming worse because warming caused by climate change is throught to make it easier for pests and diseases to survive. New pests and diseases are ariiving and the frequnecy of attack is increasing.
Why are forest fires increasing in the taiga forest?
- Forest fires are a natural part pf the ecosystem -they allow new growth and regenerate the forest
- However it is thought that climate change is leading to warmer,drier conditions in the taiga forest. This is increasing the frequency of forest fires and making the fire season longer
Why are forest fires a threat to the taiga forest
- Forest fires destroy large numbers of trees and change the distrubtion of species as some are better at recolonising burnt areas
- Forest fires also split forest into smaller sections which makes it hard for animals to migrate to find food
What is an wilderness area
A wilderness area is an area that is undisturbed by human activity that is managed with the aim of protecting the landscape
What are some strengths of a wildnerness area
- A wilderness area has the highest level of protection-most human activity is banned and the area is kept as pristine as possible
- It covers a large area so large scale processes can still take place e.g animal migrations
What are the challenges of having a wilderness area
- the large, remote area can be difficult to police
- there is economic pressure on the government from logging,mining and energy companies who want to use the resources from the area
- there is pressure from companies and tourists who want to build roads to open up the area
What is a national park
A national park is that is mostly in its natural state that is set up to protect biodiversity and promote recreation
What are the strengths of national parks
- They can be set up to protect a particular species e.g wood bison
- They can cover a large area
- Unsustainable human activity is not allowed e.g logging or mining
- There is good access for tourists are recreational users
What are the challenges of creating a national park
- National parks must take into account the needs of indigenous communities who may need the land for hunting Et
- Tourism may be required to pay for conservation,however infrastucture , access roads and pollution caused by tourist can damage the ecosystem
What is sustainable forestry
Sustainable forestry is ways of harvesting timber from the forest without damaging it in the long term
What are the strengths of sustainable forestry
- Limits can be placed on the number of trees felled or the size of clear cut areas to allow the forest to regenerate
- companies may be required to regenerate an area after logging in it
- Some existing trees will be kept as part of the new forest in selective logging
What are the challeneges of sustainable forestry
- Some countries find it hard to enforce the rules e.g in Russia a lot of illegal logging takes place
- There may be a lack of clear managment and information about the ecosystem
- Some groups may not agree with the rules e,g loggers and indegnous people
Why do some people want to protect the taiga forest
- Some people want to protect the taiga forest as the taiga forest stores lots of carbon, if this carbon is released it will add to the greenhouse affect
- Some species only exist in the taiga forest as they are specially adapted to the climate , destruction of the taiga could lead to their extinction
- Some indigenous people e.g the sami people of scandinavia rely on the forest for their traditional way of life
Why do some people want to exploit the taiga forest
People want to exploit the tiaga forest because
- Demand for resources is increasing - people want the minerals,wood and fuel the forest provides
- The forestry industry e,g logging and mining provides lots of jobs (e.g logging and mining in canada employs 25,000 people)
- Exploiting the forest generates a lot of money for the countries involved e.g swedens forestry industry generates $15 billion per year
