ABSTRACT- Despite the benefits of herbicides, their persistence in soil can harm other plants in next rotations and contaminate ground water. The main purpose of this research is to simulate 2,4-dichlorophenoxyaceticacid(2,4-D) movement in silty clay loam soil using HYDRUS-1D model in a corn root zone. The maximum contaminant level goal, MCLG, of 2,4-D in water resources is 10 ppb. The 3.5 kg a...

infiltration is a complex process that changed by initial moisture and water head on the soil surface. the main objective of this study was to estimate the coefficients of infiltration equations, kostiakov-lewis, philip and horton, and evaluate the sensitivity of these equations and their coefficients under various initial conditions (initial moisture soil) and boundary (water head on soil surf...

An overview is given of the issues of parameter estimation, model verification, and model validation as applied to field-scale subsurface flow and transport problems. We briefly review inverse optimization methods for estimating soil hydraulic parameters from a variety of field experiments, including tension disc infiltrometry, cone penetrometry, and gravity drainage experiments. An example is ...

Exfiltration of waste water in sewer networks represents a potential danger for the soil and the aquifer. Various modelling approaches have been proposed to quantify sewerage exfiltration and its spatial and temporal variation. Common models are based on the law of Darcy, extended by a more or less detailed consideration of the expansion of leaks, the characteristics of the soil and the colmati...