H. Behrendt et al., NUMERICAL AND ANALYTICAL MODEL OF PESTICIDE ROOT UPTAKE MODEL COMPARISON AND SENSITIVITIES, Chemosphere, 30(10), 1995, pp. 1905-1920
A numerical and an analytical model were both used to quantify pestici
de root uptake in the transpiration stream of cereals. The deviation o
f the calculated root uptake between both models is smaller in autumn
than in spring scenario of pesticide application and may be related to
the water balance of the scenario. The sensitive parameter ranges of
both models on soil sorption and degradation input parameters were det
ermined. In the autumn scenario the pesticide root uptake responds sen
sitive for high values of the sorption parameter related to organic ca
rbon content (Koc > 100 cm(3)/g) and for low values of the degradation
half-life in soil (< 20 days). Contrary to the autumn scenario, in sp
ring scenario the pesticide root uptake does not respond sensitive on
the degradation half-life in soil. Expressions were derived to quantif
y the nonlinear dependency of the maximum of pesticide root uptake on
chemical and scenario specific parameters. The maximum of the pesticid
e root uptake as function of sorption parameter depends on the degrada
tion rate of the chemical in the autumn scenario, but almost not in th
e spring scenario.