磁化微咸水灌溉对土壤交换性盐基离子组成的影响

Effects of Magnetic Brackish Water Irrigation on Composition of Soil Exchangeable Base Ions

在淡水资源贫乏的土壤盐渍化地区,通过对磁化微咸水灌溉后土壤交换性盐基离子组成和水溶性盐分的测定分析,探讨地下微咸水灌溉对土壤交换性盐基离子组成的影响。结果表明:(1)微咸水灌溉中土壤交换性Mg^(2+)、K^+、Na^+降低0.7%~25%,其交换性盐基饱和度(BSP)降低7.9%~32.4%;交换性Ca^(2+)和交换性盐基总量(TEB)提高6.7%~7.9%,BSP Ca^(2+)(Ca^(2+)在交换性盐基中所占百分比)提高1.5%~3.0%;(Ca^(2+)+Mg^(2+))/TEB、Ca^(2+)/K^+、Ca^(2+)/Mg^(2+)和Mg^(2+)/K^+均增加0.6%~51%,K^+/TEB则降低13.2%~31.3%;(2)磁化微咸水灌溉后,土壤交换性K^+、Ca^(2+)、TEB和BSP K^+、BSP Ca^(2+)含量提高13.2%~31.3%;交换性Na^+、Mg^(2+)和BSP Na^+、BSP Mg^(2+)均降低为9.3%~56.5%,呈显著差异水平(P<0.05),且各交换性盐基离子平均含量大小依次为Ca^(2+)>Mg^(2+)>Na^+>K^+;Ca^(2+)/K^+、Ca^(2+)/Mg^(2+)、(Ca^(2+)+Mg^(2+))/TEB、K^+/TEB均提高3.7%~47.8%,Mg^(2+)/K^+则降低47.8%~55.4%;(3)土壤交换性盐基离子与水溶性盐基离子K^+、Na^+、Ca^(2+)、Mg^(2+)之间总体呈极显著相关(P<0.01),与(Ca^(2+)+Mg^(2+))/TEB均表现为极显著相关(P<0.01)。综上所述,磁化微咸水灌溉改变了土壤盐基离子的交换特性和离子组成,对降低土壤盐渍化地区长期应用微咸水灌溉产生的土壤盐分积聚有良好的作用。

In this study,magnetic brackish water irrigation was conducted to explore the influence of magnetic brackish water on soil exchangeable base ions through the determination and analysis of soil exchangeable base ions and water soluble salt in the soil-salinization area with poor fresh water resources.The results showed that：（1）Under brackish water irrigation,the concentrations of soil exchangeable Mg^2＋,K~＋and Na~＋decreased by 0.7%to 25%,and the exchangeable base saturation values（BSP）of K~＋,Mg^2＋and Na~＋reduced by7.9%to 32.4%.The soil exchangeable Ca^2＋content and soil exchangeable base（TEB）increased by 6.7% to7.9%,and BSP Ca^2＋increased by 1.3%to 3.5%.（Ca^2＋＋Mg^2＋）/TEB,Ca^2＋/K~＋,Ca^2＋/Mg^2＋and Mg^2＋/K~＋raised by 0.6%to 51%,while K~＋/TEB declined by 13.2%to 31.3%.（2）Under Magnetic brackish water irrigation,the contents of exchangeable K~＋and Ca^2＋,TEB and BS PK~＋,and BSP Ca^2＋were improved by3.7%to 60%,but the content of soil exchangeable Na~＋and Mg^2＋,as well as BSP Na~＋and BSP Mg^2＋were reduced by 9.3%to 56.5%compared with irrigation of brackish water,presenting a significant difference（P〈0.05）and the rank of average content of soil exchangeable base ions was Ca^2＋〉Mg^2＋〉Na~＋〉K~＋.Ca^2＋/K~＋,Ca^2＋/Mg^2＋,（Ca^2＋＋Mg^2＋）/TEB and K~＋/TEB were averagely heightened by 3.7%to 47.8%,but Mg^2＋/K was decreased by 47.8%to 55.4%.（3）The soil exchangeable base ions had a highly remarkable correlation with K~＋,Na~＋,Ca^2＋and Mg^2＋of water soluble base ions on the whole（P〈0.01）,and also had an extremely significant correlation with（Ca^2＋＋Mg^2＋）/TEB（P〈0.01）.In conclusion,the magnetic treatments changed the exchange characteristics and composition of soil exchangeable ions,and could effectively reduce accumulationof soil salt caused by long-term brackish water irrigation in soil salinization region.