In modern society, only a few hundred years ago, the primitive vegetation on the Loess Plateau was severely damaged by frequent wars. With the development of society and the rapid increase of population, people plundered the natural resources such as land and vegetation to meet their own survival needs, especially the ancient agricultural production mode of extensive planting and poor harvest, which directly and thoroughly destroyed the ecological environment conditions of agricultural production itself. Scientific research has proved that good shrub and tree vegetation has at least three functions in the management of the Loess Plateau.

First, reduce the function of flood peak and conserve water. Grass shrub canopy can redistribute rainfall, especially the kinetic energy of rainstorm, so that the topsoil can absorb effective rainfall to the maximum extent. A large area of arbor irrigation basin can prolong the time of rainstorm runoff production by more than 3 times, conserve water and effectively regulate river runoff.

The second is to improve soil structure and prevent erosion. Good shrub forest soil increases the capillary pores in the surface layer and deep layer of soil, and has effective infiltration capacity, which is more than 20 times higher than that in bare land and agricultural land. It can change the runoff rate in the surface soil and increase the soil water storage capacity. Even in the secondary forest and artificial grass irrigation area, the benefit of sand control can reach 80- 100%.

The third is to improve the microclimate function. After the arbor, shrub and grass reach a certain scale, the microclimate can be improved. It can effectively curb frequent sandstorms, reduce the hot and high-temperature surface temperature, reduce the intensity of regional water evaporation, improve the surface humidity, and reduce the harm of frost and drought in the early and late stages. For decades, the research and practice of soil erosion control in the Loess Plateau have proved that only by implementing comprehensive measures such as planting grass and trees, restoring vegetation and supporting soil and water conservation projects in this special area can the Loess Plateau get the best control effect. Biological measures and vegetation construction are the "radical" projects to control soil erosion in the Loess Plateau, and the primary measure should be planting grass and consolidating soil.