脱硫石膏配施聚马来酸酐对碱化土壤的改良效果研究

摘要

Field plot experiment was carried to study the effect of applying the different amounts of desulfurized gypsum, as well as the desulfurization gypsum combined wtih polymaleic anhydride(HPMA) on alkali soil improvement in rice field. The results showed that the application of desulfurization gypsum decreased soil pH and alkalinity significantly. The biggest drop value of pH in topsoil was 1.59 and alkalinity (ESP) declined by more than 30%. The application of desulfurization gypsum affected the content of soil water soluble Na+, Ca2+, SO2-4, HCO-3and then regulated the salt content of the soil. Appropri-ate application of desulfurization gypsum significantly reduced salt content of soil, which was 1.81 g·kg-1for the largest decline, but the influence was opposite for excessive application of desulfurization gypsum. The desulfurization gypsum com-bined with polymaleic anhydride didn't decrease soil pH and alkalinity significantly, however reduced the salt content of the soil in some degree. The desulfurization gypsum combined with low amount of polymaleic anhydride significantly improved the soil alkali hydrolyzable nitrogen, available phosphorus and available potassium.%针对我国吉林地区碱化土壤的特点,通过田间小区试验,研究了水稻种植条件下不同用量脱硫石膏对碱化土壤的改良效果,同时进行了脱硫石膏配施聚马来酸酐 (HPMA) 增强改良效果的研究.结果表明,脱硫石膏可以显著降低碱化土壤pH值、碱化度,其中耕层土壤pH值最大降幅为1.59,碱化度 (ESP) 降幅在30%以上.施用脱硫石膏主要通过影响土壤水溶性Na+、Ca2+、SO2-4、HCO-3含量来调节土壤含盐量;适量施用脱硫石膏可以显著降低土壤含盐量,最大降幅为1.81 g·kg-1,过量脱硫石膏带入土壤的盐分不能及时淋洗反而会导致土壤含盐量增加.脱硫石膏配施聚马来酸酐对降低土壤pH值、碱化度无显著影响,但在一定程度可以降低土壤含盐量.从改碱与降低含盐量两方面综合考虑,建议东北碱化土壤改良过程中添加脱硫石膏的质量配比以2%为基础进行调整.