5.3 Soil Degradation and Conservation Flashcards
Degradation
The decline in the quality and productivity of land due to factors like erosion, deforestation, or poor agricultural practices.
Marginal lands
Areas of land that are not suitable for cultivation due to poor soil, lack of water, or extreme weather conditions.
Drylands
Regions with arid, semi-arid, or dry sub-humid climates where water scarcity limits the growth of vegetation.
Drought
prolonged period of abnormally low rainfall, leading to a shortage of water and negative impacts on ecosystems and agriculture.
Desertification
The process by which fertile land becomes desert, typically due to drought, deforestation, or inappropriate agriculture.
Fuelwood
Wood harvested for use as fuel, often leading to deforestation and land degradation when collected unsustainably.
Sahara vs Sahel
The Sahara is a vast desert in North Africa, while the Sahel is the semi-arid region just south of the Sahara, vulnerable to desertification.
UNCCD
United Nations Convention to Combat Desertification: An international agreement aimed at combating desertification and mitigating the effects of drought through sustainable land management.
Desertification management
Approaches include afforestation, sustainable agriculture, water conservation techniques, and creating protective barriers like windbreaks.
Great Green Wall
An African-led initiative to combat desertification by planting trees across the Sahel region to restore degraded lands and improve food security.
Enrichment
The process of adding nutrients or organic matter to soil to improve fertility and promote plant growth.
Sheet erosion
The removal of a thin layer of soil by water runoff over a large area, usually caused by heavy rainfall or poor land management.
Levee
An embankment built along a river or body of water to prevent flooding and control water flow.
Afforestation
The process of planting trees in an area where there were no previous forests, often used as a strategy to combat desertification.
Dryland salinity
The accumulation of salts in the soil in drylands, often caused by rising groundwater bringing salt to the surface, which reduces soil productivity.
Capillary rise
The upward movement of water through soil pores due to capillary action, which can lead to salinization if saline water reaches the surface.
Management of dryland salinity
Techniques include planting deep-rooted vegetation, improving water management practices, and lowering groundwater levels.
How do soils become acidic?
Excessive use of nitrogen fertilizers, organic matter decomposition, or acid rain.
How is soil acidity managed?
Adding lime (calcium carbonate) to neutralize the acidity, practicing crop rotation, and using fertilizers that are less acidifying.
Windbreaks
Rows of trees or shrubs planted to reduce wind speed, prevent soil erosion, and protect crops from wind damage.
Role of plants in maintaining soil surface stability
Plants protect soil from erosion by anchoring it with their roots and reducing the impact of wind and water.
Erosion management techniques
Contour plowing, terracing, maintaining vegetation cover, and using sediment control structures to prevent soil erosion.
Preventing land degradation in cropping
Practices include crop rotation, conservation tillage, and planting cover crops to protect the soil.
Preventing land degradation in grazing
Rotational grazing, maintaining vegetation cover, and preventing overgrazing are key strategies.
Soil conditioning (conditioner)
the process of improving the physical properties of soil to enhance its structure, aeration, water retention, and drainage, to create a more favorable environment for plant growth.
Common soil conditioners include:
- Compost
- Manure
- Peat moss
- Gypsum
- Lime
