Human Activity & Equatorial Tropical Forest (SQA National 5 Geography): Revision Note

Human activity in the equatorial tropical forest ecosystem

• People use the tropical rainforest landscape to their advantage in several ways

• But sometimes the landscape is misused, causing problems for people and the environment

​​Indigenous people

• Indigenous people, such as the Kayapo, tend to use the tropical rainforest environment in a sustainable way

  • They have lived in the rainforest for thousands of years

  • They use traditional methods to hunt and fish for their food

  • They gather fruits, nuts and roots for food and medicine 

  • They use wood from trees to build shelters and make tools and weapons

• Shifting cultivation is a traditional method of farming practised by indigenous people

  • A small area of land is cleared using axes and machetes

  • Large trees are left to provide shade and fruits

  • The rest of the vegetation is burned to add nutrients to the soil

  • This is known as ‘slash and burn’

  • Crops such as cassava and maize are then planted

  • After a few years, the soil becomes less fertile, so people move to a new location and repeat the process

  • The previous site is left to regenerate, and over time, vegetation returns

  • This does not damage the rainforest because it is practised on a small scale

Causes of deforestation

• On a larger scale, human activity can have significant impacts on tropical rainforests

• Deforestation is the felling and clearance of trees

  • More than half of the world’s tropical rainforests have been destroyed since the 1960s

• There are six main human causes of deforestation

Agriculture

• The main cause of deforestation is agriculture, such as cattle ranching and crop plantations

• Forest is cleared to create land for cattle to graze and to plant crops such as oil palm, soy and cocoa

• Benefits (uses)

  • Provides food for local and global markets

  • Creates jobs and income, boosting the economy

• Costs (misuses)

  • Soil loses fertility, resulting in the heavy use of fertilisers

  • Use of pesticides and monoculture farming reduces biodiversity

Logging 

• Trees are cut down to provide hardwood timber like teak and mahogany

• Benefits (uses)

  • The wood is valuable and used to make furniture, flooring and building materials

  • Creates jobs and income, boosting the economy

• Costs (misuses)

  • Once trees are removed, the soil is vulnerable to erosion

  • Loss of habitats and wildlife

Settlements

• As populations grow, large areas of rainforest have been cleared to create towns and cities

  • For example, Manaus in the Brazilian Amazon has a population of more than 2 million people

• Benefits (uses)

  • People move to the rainforest for job opportunities and housing

  • People can access services such as schools and healthcare, boosting the standard of living

• Costs (misuses)

  • Indigenous people may be displaced

  • Increased pollution and waste

Mineral extraction

• Rainforests hold significant oil and gas reserves

  • Nearly a fifth of the world’s recently discovered oil and gas reserves are found in the Amazon rainforest

• There are also large reserves of valuable minerals such as gold, bauxite and iron ore in the rainforests

  • The Carajás Mining Complex in Brazil is the world’s largest iron ore mine

• Benefits (uses)

  • Provides energy and valuable minerals for industries

  • Provides exports, boosting jobs and economic growth

• Costs (misuses)

  • Construction and heavy machinery damage vegetation

  • Oil spills and toxic waste pollute the environment

  • Loss of biodiversity

Transport and infrastructure

• Roads and railways are built to access resources

  • The Pan Borneo Highway in Malaysia is more than 2000km long

• Benefits (uses)

  • Increases trade and improves access to services

• Cons (misuses)

  • Leads to habitat fragmentation, hindering the movement of wildlife and disrupting ecosystems

  • Increases deforestation and air pollution

Hydropower

• Large dams are built on rivers in rainforests to generate electricity

  • The Itaipu Dam supplies over 10% of Brazil’s electricity and up to 90% of Paraguay’s electricity

• Benefits (uses)

  • Creates renewable energy which does not run out or contribute to greenhouse gas emissions

  • Provides electricity for homes and industry, boosting economic growth and the standard of living

  • Helps to control flooding

• Costs (misuses)

  • Floods large areas of forest

  • Indigenous communities are displaced

  • Loss of habitats and wildlife

Impacts of human activity in the equatorial tropical forest 

Effects of land degradation on people and the environment

Impacts on people

• Indigenous communities have less land to sustain their traditional way of life

  • Land does not get the opportunity to recover

  • There is less food available

• Land and water pollution means that indigenous people may be unable to hunt and fish for their food

  • Connection to land and culture is lost

• Indigenous people get jobs in industries such as mining

  • Quality of life may improve due to increased income and access to services

  • Cultures are threatened as indigenous people give up their traditional way of life

  • Younger generations don’t learn traditional skills like hunting and tracking

• Increased risks of flooding and landslides can destroy homes

• Plants in tropical rainforests are an important source of medicines

  • Around 25% of modern medicines are made from rainforest plants

  • Rosy periwinkle is used to make drugs that treat leukaemia

  • Deforestation may result in the loss of potential ingredients for medicines that are yet to be discovered

• Pollution leads to an increase in respiratory illnesses and cancer

• Mental health problems like depression increase due to rapid cultural change

Impacts on the environment

• Removal of trees leads to loss of habitats, threatening biodiversity

  • Deforestation in tropical rainforests could lead to the extinction of half of the world’s species

• Oil spills and toxic waste lead to land degradation

• When trees are removed, interception and infiltration decrease

  • This reduces evapotranspiration, which leads to lower precipitation

  • It also causes leaching, so the soil becomes less fertile, making it more difficult for the ecosystem to regenerate

  • Overland flow increases, leading to soil erosion and sedimentation of rivers

    • Sediment builds up in rivers, reducing their capacity and leading to increased risk of flooding

• Fewer trees mean less CO₂ is absorbed during photosynthesis

  • This means more CO₂ in the atmosphere, which contributes to the enhanced greenhouse effect

• Deforestation damages the nutrient cycle

  • When trees and vegetation are cleared, the main store of nutrients is removed

  • This makes it harder for the ecosystem to recover and regenerate

Managing human activity in the equatorial tropical

International strategies

• UN Forum on Forests was established in 2000 and is committed to the management, conservation and sustainable development of all types of forests

• The UN Sustainable Development Goals include the sustainable management of forests

• International treaties protect certain areas, such as the Central Amazon Conservation Complex (CACC), which is a World Heritage Site

  • Activities like hunting, logging and fishing are limited

• Trade restrictions on endangered species and timber have been imposed

  • The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) aims to ensure that international trade in specimens of wild animals and plants does not threaten the survival of the species

  • The International Tropical Timber Agreement (ITTA) promotes sustainable forest management and restricts the trade in rainforest hardwood timber

  • The Forest Stewardship Council (FSC) approves wood from sustainable sources 

• Debt-for-nature swaps

  • Countries are relieved of some of their debt in return for protecting rainforests 

  • In 2024, Ecuador completed one of the largest debt-for-nature swaps ever, releasing $460 million to fund conservation of its tropical rainforest

• Groups like Greenpeace and WWF monitor deforestation and promote awareness about conservation 

  • This encourages sustainable management and pressures governments to prevent biodiversity loss

• The Amazon Sustainable Landscapes Project is funded by the World Bank

  • Several Amazon countries, like Brazil, Peru and Guyana, work together to reduce deforestation and promote sustainable land use

  • They create protected areas to preserve the forest and restore degraded ecosystems through reforestation

National strategies

• Brazil's Forest Code is a law that requires landowners to maintain a proportion of their land as native forest. 

  • In the Amazon, between 50% and 80% of the land must be kept as forest

• Brazil’s DETER satellite monitors deforestation in the Amazon

  • It takes images at regular intervals to detect changes in forest cover

  • This helps to detect illegal deforestation quickly so that authorities can intervene to prevent further damage 

  • It was estimated that this led to a 60% decrease in large-scale deforestation in some areas

• There are 75 national parks in Brazil, helping to protect and conserve the ecosystem

  • Resource extraction in the parks is not allowed

  • Nature preservation, scientific research, environmental education and sustainable tourism are prioritised

• Some countries, like Malaysia, use selective logging to reduce environmental damage and help maintain biodiversity

  • It works by ensuring that only mature trees and those over a certain height are cut down

  • It restricts the number of trees cut down per hectare to maintain forest structure and promote regeneration

  • It reduces the use of heavy machinery and uses helicopters to remove the trees (heli-logging), reducing damage to surrounding vegetation

Local strategies

• Agroforestry combines agriculture with forestry, decreasing deforestation

  • Trees provide shade, which protects plants and soil from direct sunlight

    • This reduces evaporation, meaning the soil stays moist for longer

    • Working conditions are also better as people are less exposed to high temperatures

  • Trees increase infiltration and interception

    • This reduces soil erosion and prevents leaching

  • Provides organic matter from the trees and adds nutrients to the soil

  • Increases biodiversity due to the variety of plants grown

• Education of people involved in the exploitation and management of the rainforest

• The Marajó Project in Brazil preserves almost 90,000 hectares of the Amazon Forest

  • It supports sustainable activities like agroforestry, fishing and small-scale agriculture through training for local people

  • Financial incentives are used to encourage local communities to protect the rainforest

  • A tree nursery grows native trees to be planted in areas which have been cleared

    • The new trees help to bind the soil, reducing soil erosion and increasing infiltration

• Ecotourism is becoming more widespread

• Ecotourism includes:

  • A focus on the natural environment

  • Low impact on the environment – using materials from the local area and buildings to blend in with the environment

  • Supporting local communities – using locally grown food and employing local people 

  • Education – to inform tourists about the local environment and wildlife

  • Gaining income which can be used for conservation