Objective  The evolution characteristics of protection policies for black soils in China were reviewed and the reference and basis will be provided for protecting black soils in the future.

  Methods  Guided by the policy process theory, based on the policy bibliometric method and content analysis method, using the 304 national and provincial-level protection policy documents for black soils released during 1998-2021, the quantification of the protection policy intensity was proposed to analyze the intensity, quantity, and vertical and horizontal structure of policies.

  Results  The intensity and quantity of protection policies for black soils have continued to rise and show phased characteristics. Based on this, China’s protection policies are divided into the embryonic exploration stage from 1998 to 2003, the preliminary formation stage from 2004 to 2014, and the year 2015 to present three evolution stages. The majority of the policy promulgation agencies were the Ministry of Agriculture and Rural Affairs (including the former Ministry of Agriculture), the Ministry of Water Resources, and multi-sectoral joint promulgation. Policy and departmental coordination were further strengthened. The forms of the policies were mainly “notification opinions”, supplemented by technical regulations, work reports and resolutions for end-of-line control. Administrative regulations on land protection have problems such as content fragmentation and low levels of effectiveness. Policy themes were extremely unevenly distributed, focusing on protection objectives, pilot construction, and technical models. Policy tools were mainly command and control, economic incentives, and information disclosure. The use of policy tools such as type and propaganda-guided type has increased. Policy evolution has gone through three stages: budding exploration, initial formation and deepening development. 1998-2003 was the embryonic and exploratory stage. At this stage, China initially recognized the importance of protecting black soils, focusing on strengthening the prevention and control of soil erosion in the black soil area and other ecological protection content. The period from 2004 to 2014 was the initial formation stage of protection policy system, emphasizing black soil erosion control, improving the quality of arable land, and building soil and water conservation projects. The number of policies has increased at a relatively high rate. The stage of 2015 to present has been the deepening development for policy system. Compared with the previous stage, the trend of specialization of the policy system has been further strengthened, and the problem of policy fragmentation has begun to be paid attention to and gradually solved. On the whole, China's protection policy for black soils has shown an evolution from nothing to something, from single to gradually diversified in past two decades.

  Conclusion  Protection policies for black soils are continuously optimized. In the future, the goal should be to build a four-in-one systemic protection system of “quantity, quality, ecology, and rights”, to promote the legalization and enhance the degree of policy coordination. China should play the role of diversified business entities to prevent possible disconnection between policies and actual conditions, pay more attention to the balanced development of policy themes, combine with the in-depth implementation of the “land chief system”, improve the ecological compensation mechanism, and refine the protection responsibility, process management, supervision and feedback, and improve the operability of policies.