Causes, manifestations and control measures of desertification

Drought, evaporation is greater than precipitation, deep inland, far away from the sea, ocean water vapor is difficult to reach. Surrounded by mountains, the Qinghai-Tibet Plateau is blocked.

It's windy here, close to the source of the winter wind (Siberia), with small topographic relief and no mountain block, which makes the wind drive straight in. Vegetation is scarce and the vegetation coverage rate is low. The soil is loose and barren. A cold current to reduce the temperature and humidity.

Excessive reclamation, overgrazing, excessive firewood harvesting, unreasonable use of water resources, improper protection of traffic lines and other engineering construction.

2, the performance of desertification

(1) The land area of wind erosion and desertification in China is 1.607 million square kilometers, mainly distributed in arid and semi-arid areas, which is the largest and most widely distributed among all kinds of desertification land. Among them, the arid area is about 876 thousand square kilometers, which is generally distributed in the west of Langshan Mountain in Inner Mongolia. The Tengger Desert and the north of Longshou Mountain include the north of Hexi Corridor, the Qaidam Basin and its north, and the west of Tibet. The semi-arid area is about 492,000 square kilometers, which is generally distributed in the east and south of Langshan Mountain in Inner Mongolia, passing through Hangjinhouqi, Chengkou County and Wuhai City, and then passing through the central and eastern Hexi Corridor to Subei Mongolian Autonomous County, showing a continuous large-scale distribution. The sub-humid arid area is about 239,000 square kilometers, mainly distributed in the east of the Mu Us Desert and the east of Inner Mongolia, east longitude 106 degrees.

(2) The total area of water erosion desertification in China is 205,000 square kilometers, accounting for 7.8% of the total area of desertified land. It is mainly distributed in the Wuding River, Kuye River and Tuwei River basins in the northern part of the Loess Plateau, and mainly distributed in the middle and upper reaches of Xiliao River and Daling River in the northeast.

(3) The area of freeze-thaw desertification land in China is * * * 366,000 square kilometers, accounting for 13.8% of the total area of desertification land. Freeze-thaw desertification land is mainly distributed in high altitude areas of Qinghai-Tibet Plateau.

(4) The total area of salinized land in China is 233,000 square kilometers, accounting for 8.9% of the total area of desertification. The areas where soil salinization is concentrated are Qaidam Basin, Oasis around Tarim Basin, piedmont alluvial plain at the northern foot of Tianshan Mountain, Hetao Plain, Yinchuan Plain, North China Plain and Yellow River Delta.

3, desertification control measures

(1) Protect existing vegetation and strengthen forest and grass construction. While strengthening management, we should effectively solve the problems of population, livestock and stoves, and strictly protect the forest and grass vegetation in the sand area. Through afforestation, rational allocation of trees, shrubs and grasses, a multi-forest, multi-tree and multi-level three-dimensional protection system will be constructed to expand the proportion of forests and grasses. While doing a good job in manual management, we should give full play to the self-repair function of the ecosystem, increase the intensity of enclosure and protection, and promote the natural restoration of ecology. Because aerial seeding has the characteristics of high speed, less labor, low cost and good effect, it is of greater significance to restore vegetation in remote and barren areas with sparse population, inconvenient transportation and barren hills.

(2) Carry out a lasting ecological revolution in desertification areas and accelerate the process of reversing desertification. The key is to rationally allocate water resources and ensure ecological water use. For example, the unreasonable allocation system of water resources is the direct cause of the shortening of rivers, the shrinking or even drying up of lakes, the decline of groundwater level and land desertification in northwest China.

(3) Strictly implement the family planning policy, control the excessive population growth, and constantly improve the quality of the population. Improve the ideological level of the whole nation through publicity and education on environmental awareness. Care and care for the environment, consciously participate in the transformation and construction of the environment, and form the fashion of the whole society. At the same time, in areas where local desertification is very serious, grasslands and cultivated land are almost completely abandoned, and the harsh natural environment is no longer suitable for human survival, the state should carry out ecological migration in a planned way.

(4) Reverse the backward situation of relying on the weather to raise livestock and reduce the damage to grasslands. It is necessary to implement the grassland contract responsibility system, stipulate a reasonable livestock carrying capacity, vigorously promote enclosure and rotational grazing, vigorously develop artificial grassland or artificially improve grassland, and raise livestock. Accelerate the cultivation of excellent livestock and poultry breeds and optimize the structure of livestock and poultry breeds.

(5) Accelerate the adjustment of industrial structure, rationally allocate the proportion of agriculture, forestry and animal husbandry according to market requirements, actively develop aquaculture and processing industries, divert rural surplus labor force, and reduce the pressure of population on land. We can also make use of the unique advantages of light and heat, natural landscape, culture and folk customs, surplus labor and other resources in desertification areas to develop tourism, exploration and scientific research industries.

(6) Optimize the energy structure in agricultural and pastoral areas, and vigorously advocate and encourage people to use unconventional energy sources, such as wind energy, light energy and biogas, so as to reduce the damage to forests, grasslands and other resources.

(7) While doing a good job in international implementation, strengthen international exchanges and cooperation in combating desertification and strive for funds and foreign aid.