Factors Affecting Agricultural Choices (HL) (DP IB Environmental Systems & Societies (ESS))

Factors Affecting Agricultural Choices

• The types of agriculture practiced in different regions are largely influenced by environmental factors—mainly:

  • Soil type

  • Climate

• The agricultural methods that are most productive and sustainable in a particular region depend on:

  • Soil properties like fertility, structure, and water-holding capacity

  • Local temperature and rainfall patterns

• As a result, farmers adopt specific agricultural practices to suit the soil and climate conditions of each biome

  • This can lead to contrasting choices in farming methods

Steppe and prairie biome: cereal farming vs ranching

• Soil type: mollisols

  • Found in grasslands, e.g:

    • North American prairies

    • Eurasian steppes

    • South American pampas

  • Highly fertile and rich in organic matter

  • Deep, dark soils that are capable of holding moisture and supporting plant growth

  • Ideal for agriculture

• Cereal farming

  • Common in regions of steppe and prairie that receive sufficient rainfall to support crop growth

  • Mollisols support high-yield cereal crops such as wheat, maize, and barley

    • These crops thrive in these nutrient-rich soils

• Ranching

  • More common in drier areas of the steppe where water is less available for crop irrigation

  • Grasses thrive in mollisols

    • This provides grazing land for cattle and sheep

Tropical forest biome: soya beans vs cattle ranching

• Soil type: oxisols

  • Found in tropical rainforest regions, e.g:

    • Amazon Basin

    • Parts of Africa, e.g. Congo Basin, Central and West Africa

    • Southeast Asia

  • These soils are:

    • Heavily weathered

    • Acidic

    • Low in natural nutrients due to high rainfall and temperatures, which cause rapid decomposition and leaching

• Soya bean farming

  • Grown in tropical areas where soil can be fertilised and lime is added to adjust pH

  • Soya beans are valuable in global markets for:

    • Human food source

    • Oil production

    • Livestock feed

• Cattle ranching

  • Often chosen for areas where soil quality does not support crops

  • Overuse can lead to soil degradation

Desert biome: irrigated crops vs ranching

• Soil type: aridisols

  • Found in arid regions, such as deserts in e.g:

    • North Africa

    • Middle East

    • American Southwest

  • Dry, sandy soils

  • Low in organic matter and nutrients

  • They are challenging to cultivate without irrigation or soil amendments

• Irrigated crops

  • Found in areas with access to water resources for irrigation, e.g. Nile Delta or regions of California

  • With irrigation, crops like alfalfa, cotton, and various fruits can be grown, but this requires careful water management

  • Irrigation in arid areas can lead to salinisation if not managed properly

• Ranching

  • Common in areas with:

    • Limited water availability

    • Desert vegetation that provides sparse but resilient grazing for livestock

  • Often low-intensity (fewer animals per hectare) to match the limited feed resources available

Temperate forest biome: mixed arable and pasture farming

• Soil type: brown earths

  • Found in temperate forest regions, e.g:

    • Parts of Europe

    • Parts of North America

  • These soils are fertile with a balanced pH, good drainage, and moderate organic content

    • This makes them versatile for agriculture

    • They can support a range of agricultural activities, from crop production to grazing livestock

• Mixed arable farming

  • Involves growing crops like wheat, oats, and vegetables

    • Often grown in rotation to maintain soil health and fertility

  • Mixed arable farming is ideal for brown earth soils, as they retain nutrients well and support a wide range of crops

• Pasture farming

  • Common in areas where grass grows well, providing fodder for livestock like cattle and sheep

  • Rotating fields between arable crops and pasture helps prevent soil degradation