Desalination of Subsurface Pipe Drainage in Saline-alkali Land of Coastal Areas

To explore the effects of subsurface pipe drainage on desalination in saline-alkali land of coastal areas in Shandong province,the changes of buried depth of groundwater and the desalination were studied under subsurface pipe drainage technology with three kinds of spacing.The results indicated that subsurface pipe drainage technology could effectively control the buried depth of groundwater,and buried depths of groundwater all met the requirements of crop growth under subsurface pipe drainage technology with spacing of 10m,14mand 20m,of which the buried depth of groundwater was always the deepest with subsurface pipe spacing of 10m.Soil salt contents of 0~20cm and 20~40cm in depth were reduced significantly under subsurface drainage technology;Soil desalination rates of 0~20cm in depth were 59.4%,59.1%and 56.5% while soil desalination rates of 0~80cm in depth were 21.6%,21.2%and 19.7%under subsurface pipe technology with spacing of 10m,14mand 20m,and desalination rates under subsurface pipe drainage technology were higher compared to the control.Spacing of 14mand buried depth of1.2mwere recommended as the parameters for saline-alkali land of coastal areas in Shandong province.