Either the desert conquers mankind or mankind conquers the desert, which highlights the importance of reducing desertification. Under the sandy surface conditions in extremely arid, arid, semi-arid and semi-humid areas, due to the influence of natural factors or human activities, the balance of natural fragile ecosystems has been destroyed, and the land degradation process characterized by sandstorm activities has gradually formed wind erosion and aeolian landform landscape.

Extended data:

Dryland accounts for 40% of the world, of which 70% in Africa is desert and dryland. Although there are rainforests in Latin America and the Caribbean, 65,438+0/4 of its land is desertification or arid land. There are 400 million people living in desert or dry land in Asia, and the area of dry land is increasing by about 2500 square kilometers every year. Of course, dry land does not mean barren land. ?

Human activities such as production, life and war have long influenced the process of natural desertification. For example, overgrazing beyond the carrying capacity leads to vegetation loss and soil erosion, which is difficult to recover, while about half of the cattle, 1/3 of the sheep and 2/3 of the goats in the world graze in arid areas; Overplanting leads to nutrient loss and soil erosion.

Overirrigation leads to water evaporation, while salt remains in the soil, and the formed salinized land also belongs to degraded land. Irrigated cultivated land in the world accounts for 17% of the total cultivated land and contributes 40% to the world grain output. However, partly due to floods and salinization, crop yields have declined, resulting in the degradation of about 2 million hectares of land.