重庆市植烟土壤中镁的化学行为研究

采用原子吸收分光光度计测定经过连续浸提的土样中镁的化学性能。结果表明，重庆市植烟土样中水溶态、可交换态、碳酸盐结合态、有机结合态、残留态镁的含量分别为0．01、0．59、0．15、0．6、0．63cmol／kg，各形态所占的百分比分别为0．5％，29．7％，7．5％，30．3％，32％，均低于0．8—1．6cmol／kg的正常水平。植烟土壤对镁的最大吸附量为1.25mg／g，吸附作用较好，故适量施加镁肥将会促进烟叶质量的提高。

Research on the Chemical Behavior of Magnesium in Tobacco Soil in Chongqing

The chemical properties of magnesium extracted several times from tobacco soil are analyzed. The resuits indicates that the water soluble form, exchangeable form, carbonate union form, organic synthesis form and the remaining form of magnesium are 0. 01 cmol/g, 0. 59 cmol/g, 0. 15 cmol/g, 0. 6 cmol/g, 0. 63cmol/g respectively, and percentage of each form are 0.5% , 29.7%, 7.5%, 30.3% and 32%. All the data are less than the normal level of 0. 8 to 1.6cmol/g. Normally, the biggest adsorptive capacity of the soil for magnesium is 1.25mg/g, so the magnesium fertilizer should be supplied to this kind of soil appropriately to improve the quality of the tobacco.