泥炭和生物炭深埋对滨海盐渍土水分入渗特性的影响

Effects of Peat and Biochar Application on Water Infiltration Characteristics of Coastal Saline Soil

通过一维垂直积水入渗试验,将不同厚度(2.5、5 cm)的隔层材料(泥炭、生物炭)填埋至土层20 cm处,探究泥炭和生物炭添加对黄河三角洲滨海盐渍土水分入渗特性的影响。结果表明:泥炭隔层在水分入渗过程中出现优先流现象,泥炭和生物炭添加处理均能显著增加入渗历时,降低水分入渗速率和累积入渗量;水分入渗结束后,各添加处理均改变了水分的再分布,其中泥炭隔层添加较为显著,提高了0~20 cm土层的含水率(10%~12%);各处理的土壤盐分随水分入渗向深层土壤迁移,并在土层底部聚集。因此,与生物炭隔层相比,泥炭是更优的选择,且隔层越厚,阻水减渗效果越明显。该研究结果可为滨海盐渍土的开发应用提供科学依据。

In this study,the effects of different interlayer materials(peat and biochar)on water infiltration characteristics of coastal saline soil in the Yellow River Delta were investigated by using one-dimensional vertical water infiltration test.The different interlayer materials with different thickness(2.5 and 5 cm)were buried to 20 cm soil layer in the one-dimensional vertical water infiltration test.The results show that the preferential flow phenomenon appears in the peat barrier during the water infiltration process.The different interlayer materials(peat and biochar)can significantly increase the infiltration duration,and reduce the water infiltration rate and cumulative infiltration.After the soil water infiltration,each addition treatment changes the trends of water redistribution,in which the application of peat layer significantly increases the water content(10%~12%)in 0~20 cm soil layer.Moreover,soil salt in each treatment can migrate to the deep soil with water infiltration,and gather at the bottom of the soil.Therefore,compared with biochar,peat barrier is a better choice,with the increase of barrier layer thickness,the effect of reduce infiltration is more obvious.The results can provide a scientific basis for the application of coastal saline soil.