What are the causes and control measures of desertification?

Land desertification is a phenomenon caused by drought, lack of rain, vegetation destruction, overgrazing, wind erosion, running water erosion, soil salinization and other factors. The specific reasons and preventive measures are as follows. Come and find out.

Causes of desertification. Human activities

The pressure of population growth on land is the direct cause of land desertification. Overgrazing, extensive management, blind reclamation, unreasonable use of water resources, excessive deforestation and unreasonable exploitation of dry land are the main manifestations of human activities to accelerate the expansion of desertification. In addition, unreasonable irrigation methods also caused secondary salinization of cultivated land.

Second, geographical environment factors and climate factors

1, (the most important natural factor) drought, evaporation is greater than precipitation, living inland, far from the sea, it is difficult to get in touch with marine water vapor. Surrounded by mountains, the Qinghai-Tibet Plateau is blocked.

2. windy weather.

3. Close to the source of the winter wind (Siberia), the terrain is small and there is no mountain block, which makes the wind drive straight in.

4. The vegetation is scarce and the vegetation coverage rate is low.

5. Loose soil and desert (this is the basis of desertification).

6. A cold current to reduce the temperature and humidity.

Desertification control measures 1, excessive reclamation: adjusting land use structure and returning farmland to forest and grassland.

2. Overgrazing: the number of livestock is adapted to the carrying capacity of grassland.

3. Excessive cutting: Take comprehensive measures to solve energy problems (such as solar energy, etc.). ) In the farming and pastoral areas.

4. Unreasonable utilization of water resources: rational utilization of water resources.

5. The root cause of human factors: rapid population growth and prominent contradiction between man and land.

The fundamental measures to solve this problem are to control the population, improve the quality of the population and implement the ecological migration policy.

The harm of desertification is especially harmful to agriculture. April to May is the spring sowing season every year. In desertification areas, seeds and fertilizers are often blown away, seedlings are uprooted, soil moisture is lost, and seedlings are blown to death or buried. In some places, folk remedies have to be repeated and even the farming season has been missed.

Grassland degradation caused by desertification gradually reduces or even completely loses the dominant grass species suitable for livestock growth. Pasture becomes low and sparse, the yield is obviously reduced, and the livestock carrying capacity of grassland is greatly reduced.

Desertification has blocked rivers, reservoirs and canals. The Yellow River transports 654.38+0.6 billion tons of sand every year, of which 654.38+0.2 billion tons comes from desertification areas. More than 50,000 kilometers of irrigation canals in China are harmed by sandstorms all the year round.

In some areas, desertification has destroyed railway subgrade, bridges and culverts, made road subgrade and pavement desertification, forced road traffic to be interrupted, and even abandoned roads. The dusty weather caused by desertification affects the normal take-off and landing of aircraft.

Sandstorm activities destroy communication and transmission lines and facilities, and the resulting disasters threaten the safety of residents.