Application Amount of Desulfurized Gypsum from Coal Fired Power Plants on Improving the Quality of Alkalized Soil

In order to protect national grain safety and ecological safety and develop a sustainable economy,it is important to improve alkaline land with desulfurized gypsum from coal fired power plants.Representative lightly alkalized soil,medium-alkalized soil and seriously alkalized soil in Xidatan of Ningxia Province were selected in the research and used in pot and soil column simulation experiments.The goal was to determine the theoretical application amount of desulfurized gypsum to improve alkalized soil of different alkalized degrees,in order to decrease the alkalization degree and total alkali degree of the soil.It was found that the theoretical application amounts of desulfurized gypsum for lightly alkalized soil,medium-alkalized soil and seriously alkalized soil were(12,529.5),(17,256.0) and(23,563.5)(kghm~2),respectively.A field experiment using the improved alkalized soil by desulfurized gypsum to plant oil sunflower seeds verified the application amount of desulfurized gypsum.The conclusions indicate that the application amount of desulfurized gypsum determined by the pot experiment and soil column simulation experiment can be used as the reference for large field demonstration and popularization.