One of the topics studied in GCSE Geography is soil erosion and degradation. This quiz looks not only at the causes of soil erosion, but also the effects - such as how it damages ecosystems.
In the past 150 years half the topsoil on the planet has been lost. In addition compaction, loss of soil structure, loss of nutrients and an increase of salinity are damaging other parts of soil, destroying its ecosystems and the chances for plants to reclaim the land and begin to form a new ecosystem.
This loss of soil also damages other environments. It increases the pollution in the waterways and the sedimentation in streams and rivers. Blocking these waterways reduces the drainage and so removes the possibility of fish and other aquatic life breeding and occupying these valuable resources.