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Alkali-saline soil is a kind of important land resources that is widely distributed on the earth. The restoration of alkali-saline land, especially for the severe alkali-saline patches, is of great both theoretical and practical significance. This study focuses on a restoration of highly alkali-saline grassland located on the Dorbod, Heilongjiang Province. Four different methods, a chemical method of gypsum modifer, a drilling engineering method, a physical method of carrying soil landfill, and a biological improvement method of laying straws were used, respectively. The results demonstrated that all the 4 approaches can promote the recovery of severe grassland. Compared with controls, the 4 approaches increased the survival rate of seedings and improved the soil physico-chemical properties. Two interactive treatments, named gypsum-aluminium-straw sulfate and gypsum-aluminium-landfill sulfate, were applied (with 3 factors and 4 levels). The highest germination rate of Puccinellia chinampoensis was founded in the treatments of gypsum 0.14kg/m~2 + aluminium 0.009kg/m~2 + 1 straw and/or gypsum 0.21kg/m~2 + aluminium 0.003kg/m~2 + landfill with saline-alkali and sandy soil mixing ratio 1:2. However, the peak rates of Leymus chinensis and Hordeum brevisubulatum were emerged in the treatment of gypsum 0.21kg/m~2+ aluminium 0.009kg/m~2+ no straw and/or gypsum 0.21kg/m~2+ aluminium 0.006kg/m~2+ landfill with saline-alkali and sandy soil mixing ratio 1:2.The best choice for the restoration of alkali-saline grassland should be the method of gypsum-aluminium-landfill, gypsum-aluminium-straw, drilling, gypsum, landfill, straw in turn, when the reclamation effect and economic input were both considered. Comprehensive utilization of improved methods was more effective than a single one. The higher the concentration of element, the greater the effect of restoration, also with more economic cost.
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