【摘要】 滨海盐碱土透水透气性差,盐分含量高,严重制约了农业生产。为寻找较优的灌溉模式,拟开展室内土柱试验,主要分析了3种矿化度水平(3 g/L,6 g/L,9 g/L)和两种交替次序(咸淡交替灌溉、淡咸交替灌溉)条件下,黄河三角洲地区滨海盐碱土水分入渗特征及盐分分布的变化规律。结果表明:咸淡交替灌溉和淡咸交替灌溉的入渗历时均随咸水矿化度的增加而增大,且淡咸交替灌溉的水分入渗历时大于咸淡交替灌溉。咸淡交替灌溉(32.15%～33.29%)的平均土壤含水率和淡咸交替灌溉(32.95%～33.58%)差别并不显著。但咸淡交替灌溉(3.915～4.773 g/kg)的平均土壤含盐量小于淡咸交替灌溉(4.255～5.313 g/kg),且3 g/L的平均土壤含盐量远低于其他处理。总体来说,咸水,矿化度较小(例如,3 g/L)的咸淡交替灌溉有利于降低土壤盐分。更多还原

【Abstract】 Saline soil is characterized by poor permeability and high salt content, which seriously restricts agricultural production. In this study, we investigated the effects of alternate irrigation with brackish and fresh water on water and salt movement in a coastal saline soil of the Yellow River Delta region. We conducted laboratory simulation soil column experiments and monitored changes in water infiltration and salt distribution in the soil under six irrigation treatments, including three kinds of salinity(3 g/L, 6 g/L, and 9 g/L) and two sequences(brackish-fresh water and fresh-brackish water). The results showed that the duration of water infiltration into the soil increased with the rise of salinity under brackish-fresh water and fresh-brackish water, with the higher value recorded at fresh-brackish water. There was no significant difference in the mean soil water content under the brackish-fresh water(32.15%～33.29%) and fresh-brackish water(32.95%～33.58%) irrigation treatments. However, the mean soil salt content under treatement of brackish-fresh water(3.915～4.773 g/kg) was lower than that under the treatment of fresh-brackish water(4.255 ～5.313 g/kg), and much lower soil salt content was observed at 3 g/L of salinity compared with other levels of salinity. From the perspective of reducing soil salt content, saline water with lower salinity(3 g/L) is the optimal strategy for alternate irrigation with brackish and fresh water in the study region.更多还原