Describe the distribution of areas of very high soil degradation.

Suggest two reasons why areas of high soil degradation occur in Europe and/or North America.

1. 

2.

Explain two ways, other than food production, in which soil provides valuable environmental benefits for people.

1.

2.

Award [1] for a geographical overview, eg there are small areas in almost every continent.

Award [1] each for two further valid points.

Possibilities include:
• the largest single area is in China/Southeast Asia
• another large area exists in Southern Africa/Madagasgar
• Sub-Saharan Africa and Asia have largest areas of very severe soil degradation
• there is high soil degradation in the Middle East
• limited areas in Central and South America
• there is no area of very high soil degradation in Australia/New Zealand
• most areas of high soil degradation are in low income regions.

Responses that just list areas should be awarded a maximum of [1].

Award [1] for each distinct reason and a further [1] for development/exemplification.

For example: Commercial monoculture [1] may deplete the soil of certain vital minerals making it more vulnerable to erosion [1].

Other causes may include:
• overuse (possibly historical) of land/overgrazing
• climate change may be causing an increase in aridity/desertification
• rising sea levels/over-irrigation could be increasing salinization
• industrial uses including large-scale open-cast mining in which native vegetation is removed
• removal of wind barriers of vegetation to create large fields where wind erosion is likely to be increased
• Impacts of past and/or present acid rain
• urban construction.

In each case, award [1] for identifying a valid way, and [1] for offering some expansion, detail or exemplification.

For example: Soil can be used for production of biofuel crops [1]. The use of biofuel reduces dependence on fossil fuels [1].

Other possibilities include:
• soil as a store for carbon, there degradation releases vast amounts of carbon into the atmosphere
• soil supports vegetation (eg rainforest), a needed carbon store to reduce the enhanced greenhouse effect carbon
• soil regulates water resources through reduced flooding, improving quality
• soil as a basis for biodiversity – species preservation.

There were some responses that identified regions where soil degradation was very high, but few who actually recognized a pattern, namely that very high soil degradation seems to be on most continents and is found in many regions.

There were some strong responses that linked reasons for high soil degradation to the two developed regions. There were other responses that could identify a cause of soil degradation but failed to link it to the two regions in the question. Industrialization, urbanization and agro-business were often given as reasons but then the development to the degrading of soil was either non-existent or was very, very generalized. There were some very weak responses that referred to inappropriate geographical regions such as the Amazon.

Responses tended to focus on soil’s water filtering qualities, its carbon store qualities, the fact that soil is needed for the growth of rainforests as an essential carbon sink, that it can be used to grow biofuels, or that it has a high biodiversity. Responses were very varied in terms of the detail.