How to prevent and control soil erosion in the future

Interpreter: Liu Zhen, Director of the soil and Water Conservation Department of the Ministry of Water Resources: reporter Zhao Yongping

A few days ago, the State Council formally approved the National soil and Water Conservation Plan (2015-2030), which is China's first national soil and water conservation plan, an important milestone in the prevention and control of soil and water loss, and an important basis for soil and water conservation work in the future.

Soil erosion accounts for 1% of the land area, and large-scale development and construction is the main reason.

What is the situation of soil erosion in the whole country?

Liu Zhen, director of the soil and Water Conservation Department of the Ministry of Water Resources, said that according to the results of the first national water conservancy census, soil erosion in China covers an area of 2.9491 million square kilometers, accounting for 30.72% of the total land area. It can be said that we are one of the countries with the worst soil erosion in the world.

The data show that due to soil erosion, the country has lost an average of 1 million mu of arable land every year, more than 1 cm of topsoil has been lost every year in the serious areas of the Loess Plateau, the black land in Northeast China has become thinner, and the black soil layers in some places have been completely lost. Serious soil erosion threatens national ecological security, flood control security and food security.

Why is it necessary to introduce national planning?

At present, more than 70,000 small watersheds have been comprehensively managed nationwide, and more than 800,000 square kilometers have been closed and protected. Liu Zhen said: soil erosion is a major eco-environmental problem at present, and large-scale development and construction is the main cause of man-made soil erosion. The prevention and control of soil erosion involves all aspects of the work of various localities and departments, which requires overall deployment, regional prevention and control, and rational distribution, and there is an urgent need to formulate a unified plan at the national level. The Ministry of Water Resources, together with relevant departments, has worked out this national "National soil and Water Conservation Plan" after four years, combining "top-down" and "bottom-up".

Implement comprehensive prevention and protection to strictly control man-made soil and water loss from the source

What hard moves will there be in the future?

According to Liu Zhen, the plan is determined, giving priority to prevention, giving priority to protection, and implementing comprehensive prevention and protection on all lands. We will carry out key prevention in the source areas of rivers, important water sources and the ecotone of water erosion and wind erosion, strictly control production and construction projects and activities, and prohibit overgrazing, disorderly mining, deforestation and reclamation of grasslands, and strictly control man-made soil erosion and ecological destruction from the source.

In soil erosion areas, measures should be taken in accordance with local conditions and comprehensive control should be carried out. Important water sources will promote the construction of clean small watersheds, and special comprehensive management will be carried out in areas with concentrated sloping farmland and areas with dense erosion ditches.

The plan defines the control objectives: by 2020, the country will increase the area of soil erosion control by 320000 square kilometers, reducing soil loss by an average of 800 million tons a year; and by 2030, a comprehensive soil erosion control system suited to economic and social development will be established. The area of soil erosion control will be increased by 940000 square kilometers, with an average annual reduction of 1.5 billion tons of soil loss.

How to carry out follow-up supervision?

Liu Zhen said that the plan is clear, and a series of systems such as supervision and management, monitoring and evaluation of production and construction projects will be established to curb new man-made soil erosion. At the same time, to achieve dynamic monitoring and full coverage of soil and water loss caused by production and construction projects, and establish an information service system for the public. This means that anyone who touches the ecological "red line" of soil and water conservation in the future will be strictly investigated for responsibility.

23 key prevention areas and 17 key governance areas, pay attention to natural recovery, classified implementation of management

The plan divides 23 national key prevention areas and 17 key management areas, pays attention to natural restoration, and classifies the implementation of soil and water conservation projects.

According to Liu Zhen, there are three key types of prevention. Among them, the source areas of important rivers involve 32 rivers, including the Yangtze River and the Yellow River, mainly closure and protection and ecological restoration, supplemented by comprehensive treatment, to build ecological barriers; important water sources, including 87 water sources such as Danjiangkou Reservoir and Miyun Reservoir, to ensure the safety of water quality at the source through comprehensive control measures. In the ecotone of water erosion and wind erosion, a large area will be closed to reduce the harm of wind and sand and ensure the production of agriculture and animal husbandry in the region.

The plan determines that in the key management areas, comprehensive management of small watersheds of 76400 square kilometers will be implemented in the near future; through the conversion of sloping farmland into terraced fields, the harnessing area will be 1.6 million hectares. In areas with relatively serious soil and water loss, such as the northeast black soil region, the northwest loess plateau and the southwest karst area, 46200 erosion ditches will be comprehensively controlled, sediment into the river will be reduced, and a number of demonstration areas with promotion and driving effect will be built throughout the country to improve the control level and efficiency.