Method for improving medium and severe saline-alkali lands

The invention provides a method for improving medium and severe saline-alkali lands. Before winter irrigation, the soil is ridged, and furrow irrigation is carried out between every two rows of ridges. During the salt return period in spring, the ridged saline-alkali soil of the soil is removed by light scraping. Before sowing in spring, organic materials such as straws, shredded grass, wood chips, dead branches and fallen leaves harvested last autumn are crushed. During sowing in spring, the organic materials and the ridged soil after removal of saline-alkali soil are mixed and cover the surface of the soil at a thickness not affecting sowing, decomposition agent is sprayed, drip irrigation belts are laid, the soil is covered with films, and seeds are sown. Drip irrigation under film andcomposting improvement based on the humidity and temperature of crop growth are used in the method. Through a comprehensive improvement scheme combining three improvement methods, the cost is saved more than 60%, medium and s