Key Terms: Hot Desert (AQA GCSE Geography): Revision Note

Hot desert ecosystem - key word glossary

Abiotic – The non-living components of an ecosystem, such as temperature, rainfall, and soil type.

Aridity – The dryness of a region due to low precipitation, typical of desert climates.

Bedouin – Nomadic people traditionally living in desert regions, who rely on livestock herding and adapted shelters.

Biodiversity – The variety of living organisms in an ecosystem. In hot deserts, biodiversity is generally low due to harsh conditions.

Biotic – The living components of an ecosystem, including plants and animals.

Climate graph – A combined bar and line graph that shows average temperature and rainfall for a location over the year (e.g. shown on page 3).

Diurnal range – The difference between the highest daytime and lowest night-time temperatures, which is large in hot deserts.

High pressure – A descending air system found at around 30° north and south of the equator, leading to dry, cloudless skies.

Interdependence – The reliance of different elements of the desert ecosystem on one another (e.g. soil, climate, plants, and animals).

Nutrient cycle – The slow movement of nutrients in the desert due to low organic matter and limited plant growth.

Salinisation – The build-up of salts in soil, often caused by evaporation of irrigation water, making the soil infertile.

Soil – In deserts, often thin, sandy, rocky, and saline with low organic matter.

Development of hot deserts - keyword glossary

Accessibility – A challenge for development due to sparse roads, sand-covered tracks, and melting tarmac from high temperatures.

Agriculture – Often dependent on irrigation systems; includes subsistence and commercial farming (e.g. Thar Desert case study).

Ecotourism – A type of sustainable tourism that aims to protect the environment while benefiting local communities (e.g. Jaisalmer Desert Festival on page 12).

Energy development – Hot deserts are used for solar, wind, oil, gas, and coal energy production (e.g. Jaisalmer Wind Park and Bhadia Solar Park).

Indira Gandhi Canal – A major canal in the Thar Desert enabling irrigation and agricultural development.

Mineral extraction – Mining of valuable minerals like gypsum, limestone, and phosphorous, often key to desert economies.

Water scarcity – A major development issue due to low rainfall and unreliable rivers, addressed by solutions like earth dams and tobas (natural ponds).

Desertification - key word glossary

Agroforestry – Combining trees with crops to reduce erosion, improve infiltration, and add nutrients to the soil.

Afforestation – Planting trees in drylands to reduce soil erosion and restore the environment (e.g. Great Green Wall project).

Bunds / Contour stones – Barriers placed along land contours to trap water, reduce surface runoff, and prevent soil erosion (page 17 diagram).

Climate change – A contributor to desertification due to increased temperatures and less predictable rainfall.

Crop rotation – A method to preserve soil health and reduce nutrient depletion, helping prevent desertification.

Drought – Extended periods of low rainfall that reduce vegetation cover and accelerate soil erosion.

Family planning – Strategy to control population growth, which reduces pressure on land and natural resources.

Fuelwood gathering – A human activity contributing to deforestation and land degradation.

Grazing patterns – Overgrazing by livestock, particularly in nomadic communities, leads to vegetation loss and erosion.

Nomadic farming – A traditional lifestyle where herders move livestock seasonally, now limited by land pressure and national borders.

Over-cultivation – Farming the same land too intensively, depleting soil nutrients and leading to desertification.

Overgrazing – Allowing animals to eat vegetation faster than it can regrow, exposing the soil and increasing erosion risk.

Population growth – Increases demand for food, fuelwood, and farmland, placing pressure on fragile desert environments.

Soil erosion – The loss of topsoil due to wind or water, especially when vegetation is removed.

Sustainable farming – Techniques such as crop rotation, irrigation efficiency, and agroforestry that reduce environmental damage.

Toba – Natural desert pond used by local communities to store water.