Estimating Soil Characteristics and Modeling Water Movement Under Sprinkler Irrigation System Using Hydrus-1D

Abstract

Soil and water resources are of great importance to the m ank ind . As th e world population grows andincreasing incidences of pollution of so il a nd gro und wa ter are discovered, prudent management a ndprotection of these resources becomes increasingly important. Most subsurface pollution problems stemfrom activities involving the unsaturated zone between the soil surface and the groundwater tabl e. Asnatural systems are extrao rdinaril y complicat ed and the understanding and management of these resourcesca nn ot be accomplished effectively using h eu ristic means, mathematical modelling has pla yed a criticalrole in the investigation an d management of soil and water resources for th e last thr ee decade s. In thepr ese nt study, how water moves in soils und er the sprinkler irrigation sys tem ha s been co nsidered byus in g HYDRUS -1D mod e l. According to preliminar y so il and water information , soil ph ysi ca l andexpe rim ental parameters, cumulative amounts of input flow in upstream, Cumulative amounts absorbedby the roots and val ues of the cumulative output flow in downstream, have been estima ted. Suction changes,moisture, h ydraulic conductivity and flow depth a t different times during th e si mul ation ha ve b eendetermined by HYDRUS-10 Software modeling. Consequently, the soil m oisture characteristics curve andSuction relationship with hydraulic conductivity related to the under studied soil in order to soil managementfor future experiences are also determined and their mentioned graphs are presented and shown.