Geography 7.2.1 A Life Support System

Goods 

• Goods are tangible products which can be taken from the ecosystem

• Timber, food and water are all examples of goods 

• These can be sold or used to sustain communities in the ecosystem

• They are one of the four services ecosystems provide

Services

• The services provided by ecosystems are essential for life to survive

• There are four groups of services:

  • Provisioning

  • Regulating 

  • Cultural 

  • Supporting

Examples of Goods and Services

Services	Tropical Rainforest
Provisioning (Goods)	Timber Fruit/nuts Medicine Water Fuel Animal products (meat/skin)
Regulating	Climate Water quality Waste decomposition Soil quality  Disease and pest control Air quality
Cultural	Health and spiritual benefits Leisure and recreation Employment Cultural heritage Education
Supporting	Soil formation Nutrient cycling

Mining

• Minerals are used in many industries 

  • May lead to deforestation and clearance for access roads and the mines

  • Toxic chemicals are a waste product and end up in the water systems

    • This affects the river ecosystem and human health

Examples of Mined Minerals

Mineral	Use	Locations of some mining operations
Copper	Construction, cables, machinery	Chile, Peru, China
Gold	Jewellery, medicine, dentistry	China, Australia, Brazil
Aluminium	Cars, packaging, machinery	Brazil, Guyana, Guinea
Manganese	Steel, construction, machinery	Brazil, Australia, China

Agriculture

• Large areas are cleared to make way for grazing and crops

• Monocultures reduce biodiversity and impact on the food web

• Use of pesticides may affect other animals as well as the ones targeted

• Use of fertilisers can lead to eutrophication

Logging

• Felling of trees leads to:

  • Reduced interception and increased soil erosion

  • Impact on the nutrient cycle due to a lack of organic matter to add nutrients back to the soil

  • Loss of habitats and food sources for wildlife

HEP

• Construction of dams and reservoirs provides electricity but impacts on the biomes in a number of ways including:

  • Clearance of forests to make way for the dam and reservoir

  • Flooding of habitats

  • Loss of food sources

  • Affects the river wildlife as the dam can form a barrier to fish that migrate such as salmon

  • Prevents the movement of sediment downstream which affects ecosystems 

• Most human activities involve the clearance of biomes

• Once they have been cleared it is difficult to restore them

• They cannot provide the goods and services as effectively or at all

Atmosphere

• To maintain the balance of gases in the atmosphere gas exchange happens continuously between the atmosphere, plants, animals and water

• An example of this is the carbon cycle

• The plants and soils in biomes are carbon sinks

• Plants absorb CO2 from the atmosphere during photosynthesis

• When plants are eaten the carbon moves from the plant to the animal

• Some CO2 is then returned to the atmosphere through respiration

• When the plants and animals die and decompose the carbon becomes part of the soil and over millions of years may be converted into fossil fuels

• As human activity increases, CO2 in the atmosphere increases, this may be from:

  • Burning of biomass or fossil fuels

  • Deforestation: meaning less CO2 is taken out of the atmosphere

Carbon cycle 

Soils

• The nutrient cycle maintains the health and fertility of the soil

Tropical rainforest nutrient cycle

• Soils require nutrients from dead organic matter (plants and animals) to remain fertile and healthy

• Removal of the biomass means the supply of nutrients is disrupted 

• The lack of vegetation cover also leads to increased leaching and the litter may be washed away, further reducing the nutrient supply

• Tropical rainforests biomes are particularly vulnerable because most of the nutrients are held in the biomass

Regulation of water

• When trees and plants are cleared from a biome it impacts on the hydrological cycle and increases flood risk

  • Interception is decreased 

  • Soil erosion increases and soil is washed into rivers reducing their capacity

  • There is more surface run off, decreasing the length of time it takes rainfall to reach rivers

  • Infiltration decreases further increasing surface run off

• The lack of trees and plants also reduces transpiration which may then lead to less frequent and reliable rainfall

Increased resource demands

• In 2022 the world's population reached 8 billion, this increases the demand for, and pressure on, natural resources

• Increasing areas of biomes are cleared for:

  • Settlements

  • Economic activities (farming, mining, manufacturing, logging)

• Increased numbers of animals are hunted or their habitats/food sources are destroyed

• Rivers, land and the atmosphere are polluted by waste

Food and water

• More people leads to greater demand for food and water

• Land is cleared for both grazing and crops

• Commercial agriculture is increasing using larger areas across the world and more water

• Use of pesticides and fertilisers increases pollution of land and water

Industrialisation

• Increasing numbers of countries have industrialised 

• Recent industrial growth has been mainly in Asia - China and India

• Industrialisation increases wealth and resources consumption, as well as transport use

Wealth

• Average wealth has increased meaning that people have more money to spend on:

• Food 

• Water: appliances such as dishwashers/washing machines, more industries using water

• Homes: larger homes taking up more land

• Energy: production of energy uses large areas of land for power stations, extracting energy sources, wind and solar farms

• Consumer goods: the demand increases industrial production and waste

Malthus theory

• Malthus proposed his theory in 1798

• A pessimistic view on the relationship between population and resources (specifically food) which states:

  • Population growth is increasing at a faster rate than the food supply

  • There will be times when there is not enough food to sustain the population

  • As a result, population growth will stop as a result of a Malthusian catastrophe - famine, disease or war

  • These are known as positive checks as they increase the death rate

  • Preventative checks are factors which decrease the birth rate 

  • These limiting factors maintain the balance between population and resources

• Malthus's predictions were incorrect as they came before much of the technological developments which have enabled food supply to be increased

• Neo-Malthusians today base their views on Malthus' theory. They argue that:

  • We have now used most of the available agricultural land 

  • The amount of fertile land is in decline

  • Food prices are increasing

  • The population continues to increase

• They suggest that famines are one example of how Malthusian theory has proved to be correct

• Neo-Malthusians argue that population control is essential to avoid Malthusian catastrophe

Graph to demonstrate Malthus's theory

Boserup theory

• A Danish economist, Ester Boserup put forward her theory in 1965 

• An optimistic view of the relationship between population and resources (specifically food) which states that:

  • Population growth will stimulate developments in technology to increase food production

  • More efficient resources will be discovered/used

  • Renewable resources will replace non-renewable

Graph to demonstrate Boserup's theory