Laboratory and Outdoor Studies

Two particular aspects of the transport of degradable contaminants were considered in laboratory experiments that used soil originating from the field experiments described in the previous sections. Studies on diffnsion of degradable insecticides were performed in diffusion cells, while the spatial redistribntion of pesticides from a point source was measured in specially designed pans (60 cm high, 40 cm diameter). Periodic sampling and contaminant analysis enabled visnaUzation of the contaminant transport pathway. 

An equation that accounts for parathion transport, snbject to both diffnsion and microbial decomposition, can be written as 

The transport of a contaminant from a point source into the subsurface was examined for two herbicides (napropamide and bromacil), by introducing them 

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