Key Terms: Population & the Environment (AQA A Level Geography): Revision Note

Introduction - key terms

Development processes – Major human advancements (e.g. Neolithic, Industrial, and Green Revolutions) that have influenced population size, growth, and distribution.

Environmental context – The influence of physical geography (climate, soil, resources, and water supply) on population characteristics.

Exponential growth – A rapid increase in population, especially notable since the 18th century.

Growth rate – The percentage increase or decrease of a population over time.

Key population parameters – Measures such as population number, density, distribution, and change over time.

Physical factors – Elements like climate and soil quality that influence where populations can live and grow.

Population density – The number of people per unit area (e.g. per km²).

Population distribution – How a population is spread over a specific area.

Food production and consumption - key terms

Agricultural system – An open system with inputs (e.g. labour, climate), processes (e.g. cultivation), outputs (e.g. crops, livestock), and feedbacks.

Agricultural productivity – The efficiency and output of agricultural practices, influenced by system type and environmental conditions.

Commercial farming – Agriculture aimed at producing crops or livestock for profit, often intensive.

Extensive agriculture – A low-yield farming system using large areas with minimal input.

Food consumption – The quantity and quality of food intake by populations, often higher in HDEs.

Food production – The growing and harvesting of food crops and livestock; unevenly distributed due to human and physical factors.

Green Revolution – A period in the 1960s when agriculture in LDEs was modernised with new technologies and crop varieties.

Hybrid seeds – Genetically enhanced seeds used to improve crop yields.

Inputs and outputs – Resources added to or produced by farming systems (e.g. water, fertiliser, crops).

Intensive agriculture – High input and high output farming, often in smaller areas (e.g. horticulture in the Netherlands).

Nomadic pastoralism – A subsistence system involving the herding of animals across lands.

Slash-and-burn – A traditional farming method where forests are cleared for temporary cultivation.

Technological advancement – The use of improved machinery, irrigation, and crop varieties to boost agricultural output.

Climate and climate change - key terms

Chinook winds – Warm winds in North America that melt snow and extend the growing season for crops.

Climate change – Long-term alterations in temperature and precipitation patterns, affecting agricultural output and food security.

Inter-Tropical Convergence Zone (ITCZ) – A region near the equator where winds converge, influencing tropical monsoon climates.

Monsoon – A seasonal wind and rainfall pattern crucial to agriculture in South and Southeast Asia.

Polar climate – Cold regions with limited rainfall and permafrost, limiting human settlement and agricultural productivity.

Tropical monsoon climate – Climate with a distinct wet and dry season, supporting large-scale agriculture and high population densities.

Soils and human activity - key terms

Gleying – Waterlogging of soil leading to blue-grey colouring and reduced fertility.

Latosol – A deep, nutrient-poor soil found in tropical rainforest regions due to leaching and intense weathering.

Leaching – The removal of nutrients from soil by heavy rainfall, common in tropical soils.

Podsol – A thin, acidic soil found in boreal forest regions with distinct layers and low fertility.

Salinisation – The accumulation of salts in soil, often due to over-irrigation and high evaporation.

Soil compaction – Compression of soil that reduces pore spaces, limiting water infiltration and root growth.

Soil degradation – The decline in soil quality due to erosion, salinisation, waterlogging, and structural damage.

Soil erosion – The wearing away of topsoil by wind or water, reducing fertility and crop yields.

Soil fertility – The nutrient content and productivity of soil, essential for successful agriculture.

Soil profile – The vertical layering of soil, including horizons formed over time through weathering and decomposition.

Structural deterioration – Damage to soil structure, reducing air and water movement, often from heavy machinery or livestock.

Taiga – The boreal forest biome where podsol soils are common and agriculture is limited by short growing seasons.

Waterlogging – Oversaturation of soil with water, restricting oxygen and plant root development.

Food security - key terms

Fair trade – A system ensuring that producers in LDEs receive a fair price and conditions for their food exports.

Food insecurity – A lack of reliable access to sufficient, safe, and nutritious food.

Food security – The state of having reliable access to enough nutritious food for a healthy life.

Free school meals – Government provision of food to children from low-income families to ensure basic nutrition.

Genetic modification (GM) – Altering plant genes to improve resistance to drought, pests, or disease.

Green revolution – An era of rapid agricultural advancement in the 20th century aimed at increasing food production in LDEs.

Hydroponics – Growing plants in water without soil, useful in areas with poor land resources.

Malnutrition – Poor health resulting from insufficient or imbalanced diets.

NGOs – Non-governmental organisations that provide support and resources to improve food access and farming practices.

Over-abstraction – Excessive withdrawal of groundwater for irrigation, contributing to salinisation.

Sustainable agriculture – Farming methods that protect the environment, support livelihoods, and ensure long-term food production.

Trade access – The ability of countries to buy and sell food across borders, influenced by global markets and trade policies.