Global Resource Demand and Population Theories

Malthus predicted a Malthusian catastrophe, where the population outstrips food supply, leading to a sudden population crash (dieback) caused by famine, war, or disease. Neo-Malthusians argue modern issues like severe water scarcity in the Middle East and North Africa support this view.

In contrast, Ester Boserup (1965) took an optimistic view, arguing that "necessity is the mother of invention." Boserup theorised that as population grows and approaches limits, humans will develop technological innovation to increase resources through agricultural intensification. A key historical example is the Green Revolution of the 1960s, which used high-yield varieties, irrigation, and fertilisers to boost Asian cereal yields by over 200%.

Interpreting Population and Resource Graphs

To understand future resource pressure, geographers use trend analysis and data extrapolation on population and resource line graphs.

Trend Analysis (The TEA Method)

When describing patterns on a graph, follow the TEA structure:

• Trend: Identify the overall direction (e.g., "There is a non-linear, exponential increase in demand").
• Evidence: Support your point with specific numbers and units from the axes.
• Anomaly: Identify any data points that do not follow the general pattern.

Data Extrapolation and Projections

Data extrapolation involves extending the trend line beyond the last known data point to predict future values. This is how population projections are created. Organisations like the UN use different scenarios, or variants:

• Principal Projection (Medium Variant): The most likely scenario used by governments for planning.
• High Variant: Assumes high fertility; warns of a severe resource deficit.
• Low Variant: Assumes rapidly falling birth rates, leading to population stabilisation.

When analysing these graphs, look for the carrying capacity—the point of intersection where the population demand curve crosses the resource supply line. Note that the "widening gap" between variants over time indicates increasing uncertainty in the extrapolation.

Worked Example

A region's domestic water demand was $270\,\text{km}^3$ in 2000. Due to rapid industrialisation and rising standards of living, demand is projected to reach $460\,\text{km}^3$ by 2030. Calculate the percentage increase in water demand.

Step 1: Find the difference (increase) in demand.

• $\text{Increase} = 460 - 270 = 190\,\text{km}^3$

Step 2: Divide the increase by the original value.

• $190 \div 270 = 0.7037...$

Step 3: Multiply by 100 and round to one decimal place.

• $0.7037 \times 100 = 70.4\%$

$\text{Percentage Increase} = \frac{\text{New Value} - \text{Old Value}}{\text{Old Value}} \times 100$

Key Terms

• Standard of living: The level of wealth, comfort, material goods, and necessities available to a certain socioeconomic class or area.
• Industrialisation: The process of transforming an economy from primarily agricultural to manufacturing-based.
• Urbanisation: The increase in the proportion of people living in towns and cities.
• Resource demand: The total amount of food, water, and energy required by a population.
• Emerging Economy (NEE): A country experiencing rapid economic growth, usually through industrialisation, such as China or India.
• Nutrition transition: A shift in dietary consumption coinciding with economic development, typically moving from cereals to high-fat, high-protein diets.
• Exponential growth: Growth whose rate becomes ever more rapid in proportion to the growing total number or size.
• Linear growth: Growth that proceeds at a constant rate over time (e.g., 1, 2, 3, 4).
• Malthusian catastrophe: The point where population exceeds food supply, leading to a sudden population decline through famine, disease, or war.
• Technological innovation: The development of new tools, ideas, or methods to solve problems and increase efficiency.
• Agricultural intensification: Increasing food production from the same area of land through the use of technology, such as fertilisers or irrigation.
• Green Revolution: A large increase in crop production in developing countries achieved by the use of fertilisers, pesticides, and high-yield crop varieties in the 1960s.
• Trend analysis: The process of identifying patterns in data over time, often using the 'TEA' method (Trend, Evidence, Anomaly).
• Data extrapolation: Estimating a value outside the known range by extending a known trend or pattern into the future.
• Population projections: Estimates of future population size and composition based on varying assumptions about fertility, mortality, and migration.
• Principal Projection: The 'Medium' variant of population growth scenarios, used as the primary basis for planning.
• Resource deficit: A situation where the demand for resources exceeds the available supply.
• Carrying capacity: The maximum number of people an environment can support sustainably without degrading the resource base.

Exam Tips

• COMMON MISTAKE: Students often confuse 'linear' and 'exponential' growth when describing Malthus's theory; remember that Malthus believed food grows linearly (1, 2, 3, 4) but population grows exponentially (1, 2, 4, 8).
• For 8-mark 'Assess' questions on this topic, examiners expect you to weigh the factors: conclude that rising wealth in emerging economies is often the most significant driver because it drastically changes resource-intensive lifestyle habits.
• When using the 'TEA' method for trend analysis, always include the units (e.g., $\text{km}^3$ or kcal) when providing evidence from the graph.
• If asked to evaluate Boserup's optimistic theory, make sure to mention the negative environmental costs of agricultural intensification, such as chemical runoff or soil erosion, as a counter-argument.
• When discussing data extrapolation, mention that projections become more uncertain the further into the future they look, evidenced by the spreading lines of the high, medium, and low variants.