The　research　objects　are　different　kinds　of　soils　including　clay,　heave　silting　clay,　silting　clay,　clay　silt　and　sand　clay　in　Beijing　area.　The　dispersion　coefficients　of　different　kinds　of　soils　are　obtained　through　hydrodynamic　dispersion　experiment　indoors.　The　soil　column　measuring　dispersion　coefficient　is　also　experimented　on　breakthrough　curve　of　ammonia　nitrogen　and　organic　matter.　The　results　show　that　the　breakthrough　curve　of　ammonia　nitrogen　and　organic　matter　in　clay,　heave　silting　clay　and　silting　clay　is　divided　into　two　phases,　but　the　breakthrough　curve　of　sand　clay　gradually　rises　and　stays　stable　in　the　end.