脱硫石膏改良中度苏打盐渍土施用量的研究

摘要

采用盆栽试验和田间试验相结合的方法,通过种植油葵(Helianthus annus),进行了脱硫石膏施用量的试验.结果表明,施用脱硫石膏能够有效降低土壤碱化度、总碱度和pH值,但却增加了土壤全盐量;施用脱硫石膏可显著提高油葵出苗率和产量,但施用量过高会抑制油葵的生长发育.施用11 250 kg·hm-2脱硫石膏对中度苏打盐渍土改良效果最佳,最有利于油葵的生长发育,耕作层土壤碱化度、总碱度和pH值分别降至6%、0.2 cmol·kg-1和8.5以下,油葵出苗率达到70%以上,田间试验中油葵产量高达2 031 kg·hm-2,与不施脱硫石膏处理相比,增产率达到16.2%.%Both pot experiment and field experiment were carried to test planting of oil sunflower with the application of desulfurized gypsum in ameliorating soils moderate in sodic salinity.Results show that exchangeable sodium percentage (ESP),total alkalinity and pH values decreased significantly,while soil salt content increased.The germination rate and yield of the sunflower increased significantly after desulfurized gypsum was applied,but excessive application of desulfurized gypsum inhibited germination and growth of the plant.After application of 11 250 kg·hm-2 of desulfurized gypsum in the 0-20 cm surface layer of soils moderate in sodic salinity,the chemical properties of the soils improved with ESP reduced down to <6%,total alkalinity to <0.2 cmol·kg-1 and pH to <8.5,and the germination rate increased to over 70% and the yield reached to 2 031 kg·hm-2,or increased by 16.2% in the field experiment.