Black soil protection is a systematic project
FILE PHOTO: This is black soil in northeast China, and its high fertility is central to food security and rural vitalization.
Northeast China is one of the world’s three major black soil regions. The protection of black soil in this region not only concerns China’s food security, but also is of great significance to safeguarding national ecological security and realizing the global sustainable development goals.
In “The Outline of the 14th Five-Year Plan (2021-2025) for National Economic and Social Development and the Long-Range Objectives Through the Year 2035,” it is clearly stated that the project of black soil protection in northeast China should be implemented to protect the region and restore the resilience of the land. In addition, seven departments, including the Ministry of Agriculture and Rural Affairs, issued “Outlines of the National Project of Implementing Black Soil Protection (2021-2025),” in July, 2021. The sustainable use and protection of the black soil has thus been elevated to a national-level strategy.
Precious values
Some woodlands, grasslands, and wetlands in northeast China have been reclaimed in large quantities, and the carrying capacity of the black soil land is overburdened. Famous for its superior quality and high fertility, the black soil in this region is suitable for vegetation and crop growing and is recognized as one type of the most fertile soils in the world. The formation of black soil is extremely difficult, and it takes 200-400 years for a black soil layer of about one centimeter to form. In fact, the black soil layer is essentially a black humus layer, which is rich in decomposed materials. The humus layer is formed after a large number of dead branches and leaves fall on the soil, integrate deep into it, and evolve after thousands of years under exposure to the natural environment. In general, the content of organic matter contained in the black soil layer can reach 5-10 times that of yellow soil. As a gift of nature, the black soil is also non-renewable, which makes it even more so invaluable.
The black soil region in northeast China is special both in its economic status and ecological status. As a crucial area advantageous in food production, it is also China’s largest base for commercial and marketable food production. In this sense, the region plays a role as the bedrock for national food security. According to statistics, there are about 8.15 million hectares of cultivated black-soil land in northeast China, and the food output yielded by the land in 2019 amounted to 61.32 million tons, accounting for 44.4% of total output in northeast China, and 9.2% of the total output in China nationwide.
In addition, there are also two globally important wetland ecosystems in the black soil region—the Zhalong and Xianghai natural reserves. The rich biodiversity that characterizes this region is of great significance for maintaining national ecological security.
While China is embracing a new stage of development, the black soil region faces the challenges brought by the superposition of two factors—the necessity for social and economic development in northeast China, and the construction of several major national engineering projects. This may increase the soil’s risk of being overexploited, with accelerating decline of soil acreage and diminishing quality. Due to an irrational soil use structure and the perennially continuous method of farming, the humus layer is getting thinner and with lowering soil quality. Moreover, the land’s productivity has decreased since the soil is heavily used but not well maintained. In addition, the fertilizing structure is mainly characterized by chemical inputs and excessive use of plastic film use, which has led to the deterioration of soil texture, hardening soil layers, and less organic materials.
Protection as national strategy
The protection of black soil in northeast China is a complex and systematic project, which involves many sectors such as the national development strategy, coordinated urban and rural development, food security, ecological and environmental security, and so on.
It is advisable to clarify the status quo of relevant resources, and make accurate evaluations on trends and changes in the future. To be concrete, it is necessary to conduct general investigations on the resources and monitor them in a dynamic way. In addition, details can be registered about how the soil is distributed and the way it is currently being used. The new-type geographic information technology can be used for accurate spatial records, which provide a scientific and systematic basis for the soil protection.
Furthermore, the crop rotation system (planting various crops in turns) can be adopted based on different local conditions, in consideration with the climate of areas of black soil coverage. The extension of fallow periods to some extent is also suggested. In addition, the recycled use of straw and other crops can constantly improve the content of organic materials encompassed by the tillage layer, which further enhances the quality of black soil in a sustainable way.
Yu Fawen is a research fellow from the Rural Development Institute at the Chinese Academy of Social Sciences.