Geography
Chapter 7: Fragile environments
Ecological footprint: measure of the mark that we humans make on the natural world. It considers how much land and sea are required to provide us with the energy for our lifestyles.
Sustainability: actions and forms of progress that meet the needs of the present reducing the ability of future generations to meet their needs.
Soil erosion and desertification
Soil erosion * The washing or blowing away of top soil. * There are three types: * Sheet erosion – occurs in parts with moderate rainfall * Gully erosion – occurs where there’s intense rainfall and little vegetation cover. Force of water cuts gullies in slopes :O! * Wind erosion – occurs in dry parts of world * What makes soil erosion worse? * Deforestation and removing vegetation. As a result of this soil gets exposed to wind/rain * Overgrazing by animals. Result is same as above * Over cultivating the soil! Especially monoculture which weakens the soil and structure and removed minerals from soil * Compacting the soil by use of heavy machinery. This encourages more run off which encourages soil erosion * Ploughing fields in the same direction as the slopes. Encourages gullying :P
Desertification
* The process of how once productive land gradually changes into a dessert-like landscape * Natural causes of desertification: * Changing rainfall patterns * Soil erosion * Intensity of rain: because when rainfall falls only a little does so it makes it hard for the soil to capture and store the water * Human causes of desertification: * Population growth: more population = more food needed = more pressure on land * Overgrazing * Over cultivation: intensive use of marginal land = soil exhausted and so crops wont grow * Deforestation: which leads to soil erosion
Consequences and management of soil
Ecological footprint: measure of the mark that we humans make on the natural world. It considers how much land and sea are required to provide us with the energy for our lifestyles.
Sustainability: actions and forms of progress that meet the needs of the present reducing the ability of future generations to meet their needs.
Soil erosion and desertification
Soil erosion * The washing or blowing away of top soil. * There are three types: * Sheet erosion – occurs in parts with moderate rainfall * Gully erosion – occurs where there’s intense rainfall and little vegetation cover. Force of water cuts gullies in slopes :O! * Wind erosion – occurs in dry parts of world * What makes soil erosion worse? * Deforestation and removing vegetation. As a result of this soil gets exposed to wind/rain * Overgrazing by animals. Result is same as above * Over cultivating the soil! Especially monoculture which weakens the soil and structure and removed minerals from soil * Compacting the soil by use of heavy machinery. This encourages more run off which encourages soil erosion * Ploughing fields in the same direction as the slopes. Encourages gullying :P
Desertification
* The process of how once productive land gradually changes into a dessert-like landscape * Natural causes of desertification: * Changing rainfall patterns * Soil erosion * Intensity of rain: because when rainfall falls only a little does so it makes it hard for the soil to capture and store the water * Human causes of desertification: * Population growth: more population = more food needed = more pressure on land * Overgrazing * Over cultivation: intensive use of marginal land = soil exhausted and so crops wont grow * Deforestation: which leads to soil erosion
Consequences and management of soil