Geography paper 1 section B

what is an ecosystem?

An ecosystem is a natural system made up of biotic (living e.g. plants) and abiotic (non-living, e.g. sunlight) components.

Example of a small scale ecosystem?

A pond is an example of a small scale UK ecosystem. Different components perform different functions in an ecosystem.

3 components which perfom different functions in an ecosystem?

Producers , consumers, decomposers

What do producers do?

They receive their energy from the sun and convert this into biomass (e.g. plants)

What do comsumers do?

They receive energy by eating producers or other consumers (e.g. fish)

What do decomposers do?

They recycle nutrients by breaking down dead plants and animals and returning nutrients to the soil (e.g. fungi and bacteria)

What does food chains and food webs show?

The biotic and abiotic components interect. Food chains and more complex food webs show how energy moves through different trophic levels in an ecosystem.

What happens when one component in an ecosystem changes?

Changing one component in an ecosystem has knock on effects on all components. If frogs were removed, mayflies could thrive, affecting other parts of the ecosystem.

distribution and characteristics of tropical rainforeests?

Roughly 1-10^o north and south of the Equator. Hot and wet climate. Lush and diverse vegetation

distribution and characteristics of hot deserts

Roughly 15-35^o north and south of the equator. Hot and dry climate. Sparse vegetation like cacti.

distribution and characteristics of Temperate grassland

Roughly 25-40^o north and south of the equator. Hot summers and cold winters with wet and dry seasons. Mostly grasses.

distribution and characteristics of temperate deciduous forest?

roughly 30-60^o north of the equator. Mild and wet climates with four seasons. Broadleaf trees that lose their leaves in winter, like oaks.

distribution and characteristics of tropical grassland (savanna)

Roughly 10-20^o north and south of the Equator. Hot climate with wet and dry seasons. grasses with occasional trees.

distribution and characteristics of coniferous forests?

Roughly 50-60^o north of the equator. cold and dry winters and mild summers. Evergreen trees like pines and firs.

distribution and characteristics of Tundra

Roughly 60-75^o north of the equator. cool summers and cold winters. Low-lying vegetation like mosses and lichens.

Characteristics of a tropical rainforest

The climate in a tropical rainforest is hot all year round. Average temperatures are 27^oC. Rainfall is high but it is very high for 6 months of the year. Rainforests also create their own climate through the water cycle. Heavy rainfall is rapidly returned to the atmsphere through evaporation and transpiration. This then condenses into clouds, leading to more rainfall.

The hot and wet climate provides ideal conditions for plant and animal species to thrive. Tropical rainforests have more biodiversity than any other ecosystem, containing half of the Earth’s land-based plant and animal species.

The soil in the rainforest have few nutrients because nutrients are leached (washed out) by the heavy rain. However, rapid nutrient recycling means nutrients are stored in the biomass (plants) rather than the soil.

Rainforest nutrient cycle

1. Leaves fall to the ground (rainfall washes some nutrients away and adds some nutrients.)

2. leaves rapidly decompose

3. nutrients added to the soil (some nutrients washed away and some nutrients added from weathered rocks)

4. nutrients taken up by plants

5. Most nutrients are stored in the biomass (plants)

Rainforest structure

1. Forest floor

2. shrub layer

3. under canopy

4. canopy

5. emergents

What is the forest floor

a thick layer of dead leaves, branches and roots

How big is the shrub layer?

There are few shrubs because there is little light

What is the under capnoy layer?

Younger trees fill in gaps in the canopy

What does the canopy layer do?

a continuous layer blocking the light

What are emergents

these are the trees which break through the canopy

Animal adaptations for living in a rainforest

Mnay animals like the leaf-tailed gecko, are camouflaged agaianst predators.

Spider monkeys have long limbs and prehensile (gripping) tails to help move through the trees.

Plant adaptations for living in rainforests

Lianas are vines that reach the light by wrapping around trees

Some plants have waxy drip tip leaves so rainwater runs of easily.

Deforestation of the amazon rainforest?

The amazon is the world’s largest rainforest, 60% of which is in Brazil. Deforestation has been rapid since the 1970’s, with an average of 6000 football pitches cut down every day. Deforestation peaked in 2004, but after a decade of decline has recently been increasing again. The main reason for deforestation is economic development. Many people in Brazil want to explout the Amazon’s resources in oder to develop.

Causes of deforestation

Logging, road building, subsistence farming, mineral extraction, commercial farming, energy development and settlement and population growth.

How does logging cause deforestation?

Logging accounts for about 2% of deforestation. Much of it is illegal. Valuable hardwood trees like mahogany are cut down and exported for furniture.

How does Road building cause deforestation?

Road building only accounts for a small amount of deforestation but is significant because it opens up the rainforest to subsistence farming, logging, and other activities.

How does subsistence farming cause deforestation?

Subsistence farming accounts for about 25% of deforestation. This is when local brazilians move into the Amazon to grow food for themselves and their families.

How does Mineral extraction cause deforestation?

Mineral extraction like golf and copper mines produce exports for the global market. The iron ore mine at Carajas is the world’s largest mine, employing 3000 people.

How does Energy development cause deforestation?

Energy development is when generated hydroelectric power floods huge areas of land.

How does settlement and population growth cause deforestation?

Towns like Manaus near Carajas grow through migration as people move from other parts of Brazil in search of work

How does Commercial farming cause deforestation?

It accounts for about 70% of deforestation, mostly due to cattle ranching. Trees are cut down to provide land to rear cattle to supply the beef and leather industries. There are also large commercial farms growing crops like soy.

how does local climate change impact deforestation in the Amazon

Rainsorest trees create a local water cycle by releasing moisture through evapotranspiration.

Rainforests generate 75% of their own rain this way

Removing trees leads to a drier and hotter environment

Summer temperatures in the Amazon have increased by 3.2^oC since 1980.

This causes more frequent drought and forest fires, destroying more trees.

How does global climate change impact deforestation in the Amazon

The Amazon absorbs 25% of global CO₂

The amount it absorbs has reduced 30% since 1990.

The Amazon also stores 150 billion tonnes of carbon

Deforestation releases stored carbon, contributing to the enhanced greenhouse effect

Brazil’s CO₂ emissions rose by 9.5% in 2020, largely due to deforestation.

How does increased soil erosion impact deforestation in the Amazon

Trees bind the soil together and protect it from heavy rainfall

Deforestation means the soil is washed away

Nutrients in the soil are also washed (leached) out.

Most rainforest nutrients are stored in the vegetation, so the soil quickly becomes infertile

This means more trees need to be cut down for grazing cattle and growing crops

How does economic growth impact deforestation in the Amazon

Activities like logging and mining have created wealth for many people in Brazil

8% of Brazil’s GDP comes from the Amazon

This means money can be spent on health, education, and building infrastructure

but deforestation has negative impacts on local global climates

The estimated cost of global reduced crop yields caused by Amazon deforestation is US$3.6 trillion over the next 30 years.

The value of tropical rainforests

Rainforests worldwide are important to the people and the environment

• They absorb and store CO₂, reducing the enhanced greenhouse effect

• They regulate local and regional water cycles, reducing drought

• They are home to half the world’s plant and animal species

• 25% of the world’s medicines come from rainforest plants

• They provide many resources like fruit, rubber, and hardwood

• Indigenous tribes live in the rainforest.

Strategies to sustainably manage tropical rainforests

Selective logging, replanting, Conservation, education, ecotourism, international tropical hardwood agreements and debt reduction

What is selective logging with an example

What is it?

Instead of clearing big sections of forest, only specific trees are felled. These are removed by helicopters or dragged out by animals like elephants

Example: heli-logging is used in Malaysia.

One advantage and disadvantage of selective logging

Advantage

The cycle of destruction is managed and the forest can regenerate.

Disadvantage

The amount of timber obtained is reduced.

What is Replanting and give an example?

What it is?

Forest seeds grown in nurseries are planted to recreate the original forest

E.g. Conservation international is planting 73 million trees in the Amazon.

One advantage and disadvantage of Replanting

Advantage

Some success, especially if done soon after deforestation.

Disadvantages

Impossible to recreate the ecosystem

What are conservations. give one example

What it is

National parks and nature reserve are established to stop deforestation

E.g. Corcovada National Park in Costa Rica

One advantage and disadvantage of Conservations

Advantage

Effective at preserving the forest

Disadvantage

economic development opportunities are reduced

What is education with an example

What it is?

Local people are taught more sustainable ways to make money from the rainforest. People in HICs are encouraged to stop buying products that damage the rainforest.

E.g. The rainforest Alliance work with farmers in Peru to promote sustainable coffee production

One advantage and disadvantage of education

Advantages

Money is earned in a more sustainable way

Disadvantages

Relies on goodwill rather than legal agreements

What is ecotourism and give an example

What it is?

Small-scale tourism where tourists stay in ecolodges and are educated about the rainforest by local guides

E.g. Monteverde Cloud Forest in Costa Rica

One advantage and disadvantage of ecotourism

Advantages

Local people earn money through conserving the environment

Disadvantages

too small scale to have a large economic benefit

What is international tropical hardwood agreements and give an example

What it is

The 2006 International Tropical Timber Agreement ITTA promotes the sale of timber from sustainable sources (e.g., selective logging) by registering each tree felled.

E.g. ITTA

One advantage and disadvantage of international tropical hardwood agreements

Advantages

Covers 80% of tropical rainforests

Disadvantages

Illegal trade in hardwood is difficult to stop

What is debt reduction and give one example

What it is

Cancelling part of a country’s debt in exchange for conservation of the rainforest. This reduces the economic need for deforestation and has become known as ‘debt for nature swapping’

E.g. The USA paid $21 million to Brazil in 2010 in return for rainforest conservation

One advantage and disadvantage of debt reduction

Advantages

Makes conserving the rainforest economically beneficial

Disadvantages

Has a minimal impact with less than 1% of debt typically affected.

where are polar and tundra environments located

Polar ecosystems are found in the Arctic and Antartic. Tundra is found just south of the Arctic at 60^o to 70^o north.

describe the climate in polar environments

• winter temperatures fall below -50^oC

• Low precipitation

describe the soil in polar environments

Land is covered in ice so no soil is exposed

describe the plants in polar environments

• Little vegetation

• mosses and lichens on rocks

Describe the animals in polar environments

• very low biodiversity

• too cold for most animals

• few insects

• polar bears, penguins, whales, and seals live in the ocean and on the fringes of the ice

Describe the people in polar environments

• some indigenous people

• no permanent residents in Antarctica- only scientists

Climate, soils, plants, animals, and people in Tundra environments

• Winter temperatures fall to -20^oC

• Warmer summers

• Some precipitation, especially in coastal areas

Describe the soil in tundra environments

• Soils frozen (permafrost) but top layer (active layer) melts in the summer

• can become waterlogged

• infertile and acidic

Describe the plants in tundra environments

• Low-growing plants and mosses

• Low bushes and small trees in warmer regions

Describe the animals in tundra environemnts

• Low biodiversity

• more food options for animals

• Reindeer, foxes, hares and birds like ptarmigans

• Insects like midges and mosquitoes, especially in the summer

Describe the people in tundra environments

• Indigenous people and settlements built around mineral (coal/oil) extraction

Issues related to biodiversity

The cold climate and harsh conditions mean that cold environments have low biodiversity. When the ecosystem is damaged, it takes a long time to recover because the growing seasons are short. Global warming is melting sea ice and threatening many species like polar bears, walruses, and seals.

Interdependence in cold environments

All parts of an ecosystem are linked

Describe a cold environment ecosystem: soil, plants, people, animals

Soils

• permanently frozen (permafrost).

• Few nutrients

Plants

• the climate allows little diversity. Slow decomposition when plants die

People

• too cold for most humans.

• No agriculture and few food sources.

• Difficult to build in frozen ground

Animals

• the climate and limited food allos low diveristy.

• Herbivores live off plants and carnivores live of herbivores.

Animal adaptations to cold environments

• thick fur to keep warm

• white fur to camouflage

• insulating fat

• wide feet and large claws to grip on ice

• black nose to absorb sunshine

• strong sense of smell to find food

Types of Animals: Polar bear, arctic foxes, hares

Plant adaptations to cold environments

Flowers very quickly in the short growing season

low growing to protect it from wind

A cushion-like texture to retain heat

Shallow root systems in frozen ground

Hairy stems to retain heat

Thick and waxy leaves to reduce water loss.

What is a landscape

A landscape is an area whose character has been shaped by the interaction of physical and human processes.

How is the UK’s landscape divided?

The UK’s landscapes are broadly divided by the Tee-Exe lines running from the mouth of the River Tees in north-east England to the mouth of the River-Exe in south-west England.

What is the Upland and lowland landscapes in the UK and how is it created?

North of this line are upland landscapes, south of this line are lowland landscapes. These landscapes are created by physical processes and human activity.

Upland Landscapes examples and features

• scotland, north and west England, Wales and Northern ireland.

• Hard, resistnt rocks like granite and slate

• In the north, Wales, and in Northern Ireland, glacial features like aretes, pyramidal peaks and U-shaped valleys.

Lowland Landscapes examples and features

• south and east of England

• Less resustant rocks like clays and chalk

• Rolling hills and flat fens

Describe the UK’s river systems

The UK has an extensive system of interconnected rivers. The longest river is the River severn, which starts the Cambrian Mountains in wales, flows into England where it is joined by the River Avon, and then flows into the Bristol Channel.

Why do Cold Environments need to be protected

• Indigenous people like the inuit live there, depending on the fragile ecosystem for their way of life

• Untouched wilderness environments are important for scientific study

• Mnay plant and animal species only live in cold environments, so need protecting

• Thie white snow and ice reflect the Sun’s energy back to space. If the snow and ice melts, global warming will quicken

• Permafrost is a big store of methane. If melting gets quicker, then lots of methane will be released, adding to the enhanced greenhouse effect.

Strategies to balance economic development with conservation

Use of technology

international agreements

Role of governments

Conservation groups

How does the use of technology help balance economic development with conservation?

The Trans-Alaska pipeline allows the oil in the Arctic to be transported without using ships. It is raised above the ground to prevent the hot oil melting the permafrost and to allow caribou to move underneath it when they migrate

How does international agreements help balance economic development with conservation?

The 1959 Antarctic Treaty prevents economic development and controls tourism in Antarctica. The Arctic Council is an international organisation of eight countries who collaborate to manage the Arctic in a sustainable way.

How does the role of the government help balance economic development with conservation

Governments can create laws to protect the environment. The Arctic National Wildlife Refuge in Alaska was established in 1960 and protects 19 million acres from economic development.

How do conservation groups help balance economic development with conservation

Greenpeace campaigns for a ban on oil drilling and large-scale fishing in the Acrtic. The World Wildelife Fund helps protect Arctic environments.

Name a case study for challenges and opportunities in cold environments?

Svalbard islands

Challenges of development in svalbards

Extreme temperatures, provisions of buildings and infrastructure, inaccessibility.

How is extreme temperature a challenge in the development of svalbard?

Daily temperatures can be as low as -30^oC. This makes it difficult fot people to work outside and for machinery to operate.

How is provision of buildings and infrastrucutre a challenge in developent in svalbard?

Building on permafrost means buildings need to be raised above ground level so the heat they give off does not melt the land underneath (figure 2). Buildings sink (suffer from subsidence) and topple over if the permafrost melts. Roads are built on gravel to stop the permafrost melting and heated water pipes are also kept off the ground.

How is inaccessibility a challenge in development in svalbard?

Svalbard is very remote with only one main airport. There are few roads outside of Longyearbyen and most people use snowmobiles or 4×4s.

Opportunities for development in svalbard?

Mineral extraction, fishing, tourism, energy?

How does mineral extraction create opportunities for development in svalbard?

Coal mining was once the most important economic activity and still employs around 300 people.

How does fishing create opportunities for development in svalbard?

Fish stocks are plentiful in the Barents Sea off svalbard. Cod and herring are popular and fishing is controlled jointly by Norway and Russia.

How does tourism create opportunities for development in svalbard?

In 1990 there was virtually no tourism in svalbard but it is now the biggest employer. 2018 saw 85,000 visitors and a further 45,000 on cruise ships coming for attractions like the Northern lights, dog sled trips, and ice cave visits. Large visitor numbers can damage fragile ecosystems.

How does energy create opportunities for development in svalbard?

Burning coal is controversial because of climate change. All of Svalbard’s energy is providd by the coal-fired power station at Longyearbyen, solar energy in the summer months (when there is 24 hours of sunlight a day) or geothermal energy might provide greener alternatives in the future.