Many
technologies have been studied for reduction of cadmium in rice grain. Water management in paddy fields
may be used as a method to reduce cadmium uptake in rice plants as the Ministry of Agriculture, Forestry
and Fisheries and National Institute for Agro-Environmental Sciences, Japan (2002) recommended the
flooding water of paddy before and after the heading, and soil improvement using fertilizers for minimizing
cadmium uptake in rice plants. The percolation pattern is related to hydraulic conductivities of the soil layers
and hydraulic conditions such as groundwater level (Adachi et al. 1992), which may acts as controllers of
soil redox potentials, consequently the uptake of cadmium in the rice plants. In paddy field, water is needed
for saturating soil, surface ponding, percolation seepage (bund percolation) and evapo-transpiration (Adachi
et al. 1992). Sasaki et al. (2009) studied a polluted paddy field model but did not include soil dressing
treatment, therefore the purpose of this study is to clarify the influence of percolation pattern on growth and
yields of rice plants and uptake of cadmium with soil dressing polluted paddy fields models.