what are the reasons and measures of land degradation
Answers
1. Deforestation:
Forests play an important role in maintaining fertility of soil by shedding their leaves which contain many nutrients. Forests are also helpful in binding up of soil particles with the help of roots of vegetation. Therefore, cutting о forests will affect the soil adversely.
2. Excessive Use of Fertilizers and Pesticides:
Fertilizers are indispensable for increasing food production but their excessive use has occasioned much concern as a possible environmental threat. Excessive use of fertilizers is causing an imbalance in the quantity of certain nutrients in the soil. This imbalance adversely affects the vegetation.
3. Overgrazing:
Increase in livestock population results in overexploitation of pastures. Due to this, grass and other types of vegetation are unable to survive and grow in the area, and lack of vegetation cover leads to soil erosion. Millions of people in Africa and Asia raise animals on pastures and rangelands that have low carrying capacity because of poor quality or unreliable rainfall Pastoralists and their rangelands are threatened by overgrazing.
Pastoral associations in West Africa have tried with mixed success to improve the productivity of common held livestock pastures. The Aga Khan Rural Support Programme has been successful in improving management of common grazing lands.
5. Water-logging:
Excessive irrigation and improper drainage facility in the fields cause rise in the ground water level. This ground water mixes with surface water used for irrigation and creates a situation called water-logging. Ground water brings the salts of soil in dissolved state up to the surface where they form a layer or sheet of salt after evaporation. The term salinity is used for such a situation.
6. Desertification:
Desertification is a widespread process of land degradation in arid, semi- arid, and dry sub-humid areas resulting from various factors, including climatic variations and human activities. The UNO Conference on Desertification (1977) has defined desertification as the “diminution or destruction of the biological potential of land, and can lead ultimately to desert like conditions.
Answer:
What is land degradation?
Land degradation is caused by multiple forces, including extreme weather conditions particularly drought, and human activities that pollute or degrade the quality of soils and land utility negatively affecting food production, livelihoods, and the production and provision of other ecosystem goods and services.
Threats to land integrity
Land degradation has accelerated during the 20th century due to increasing and combined pressures of agricultural and livestock production (over-cultivation, overgrazing, forest conversion), urbanization, deforestation, and extreme weather events such as droughts and coastal surges which salinate land. Desertification, is a form of land degradation, by which fertile land becomes desert.
What does land degradation mean for health?
These social and environmental processes are stressing the world's arable lands and pastures essential for the provision of food and water and quality air. Land degradation and desertification can affect human health through complex pathways. As land is degraded and in some places deserts expand, food production is reduced, water sources dry up and populations are pressured to move to more hospitable areas. The potential impacts of desertification on health include:
higher threats of malnutrition from reduced food and water supplies;
more water- and food-borne diseases that result from poor hygiene and a lack of clean water;
respiratory diseases caused by atmospheric dust from wind erosion and other air pollutants;
the spread of infectious diseases as populations migrate.
Explanation: