不同改良剂对滨海盐碱化土壤水盐运移特性的影响

为了探究表层(0~20 cm)掺加不同改良剂对盐碱化土壤改良的效果,以黄河三角洲地区中度盐碱化土壤为研究对象,利用室内一维垂直积水入渗试验,表层掺加2种改良物质,即河沙、生物炭,设置7个处理分别为CK,S1,S2,S3,C1,C2,C3,以研究其改良效果.结果表明:在不同河沙、生物炭用量下,改良措施均能提高土壤水分入渗性能,其中生物炭改良措施显著提高了掺加层含水量,河沙改良措施显著提高了土壤掺沙层以下土壤含水率;不同改良处理下,河沙改良措施相较于生物炭改良措施更有利于盐碱化土壤脱盐,处理S3的平均脱盐率比掺生物炭处理提高14.5%~27.7%,脱盐区深度、达标脱盐区深度均超过了0~50 cm作物根系密度较大的土层.根据河沙和生物炭在室内一维垂直积水入渗试验结果,土壤表层掺沙可有效改良黄河三角洲地区盐碱化土壤的水盐分布,为作物生长提供良好的环境.

Effects of different modifiers on water-salt transport characteristics in coastal saline-alkaline soils

In order to explore the effects of surface layer(0-20 cm)mixed with different modifiers on salinized soil improvement, taking the moderate saline-alkaline soil in the Yellow River Delta as the research object, and one-dimensional vertical water infiltration experiments were conducted. Two modifiers were added to the surface layer, namely river sand and biochar and seven treatments, including CK, S1, S2, S3, C1, C2 and C3 were set up to study their improvement effects. Under different river sand and biochar dosages, two modifiers can improve soil water infiltration performance. Among them, the modifier biochar can significantly increase the water content in the mixing layer, and the modifier river sand can considerably raise the soil water content below the sand mixed layer. Across different treatments, the modifier river sand is more conducive to desalination of saline-alkali soils than the modifier biochar. Specially, the average desalination rate of treatment S3 is(14.5-27.7)% higher than that the treatments with biochar, and both the depth of the desalting zone and the depth of the standard desalting zone exceed the 0-50 cm soil layer with relatively high root density. Through the results of indoor one-dimensional vertical water infiltration test on the river sand and biochar, it is showed that the added sand to the soil surface layer can effectively improve the water and salt distribution of salinized soil in the Yellow River Delta, and provides a good environment for crop growth.