%0 Journal Article %T Application of Mathematical Modeling to Determine The Size of On-Site Grass Filters for Reducing Farm Pesticide Pollution %J Journal of Agricultural Science and Technology %V 5 %N 3 %U http://jast.modares.ac.ir/article-23-285-en.html %R %D 2003 %K Atrazine, DRAINMOD, Grass strips, Metolachlor, Metribuzin, PRZM2, Subsurface drainage, %X This paper presents a mathematical approach for estimating the size of a grass filter area for removing pesticide residues from agricultural drainage waters. The method util-izes a water table management model, DRAINMOD, for simulating drainage waters from agricultural land and then a solute transport model, PRZM2, for simulating pesticide concentrations in drain effluent discharging from grass filters. DRAINMOD was used to estimate daily drain outflows that occurred in a 100 ha subsurface drained field in the Ot-tawa-St. Lawrence lowlands by running the model for a one-in-twenty year annual rain-fall period. Atrazine (AZ), metolachlor (MT) and metribuzin (MZ) are the most common herbicides that are found in drainage waters. The simulated drain outflows were as-sumed to contain 50 µg/l of AZ, MT and MZ residues, and simulations were carried out with PRZM2 to determine the required size of grass filter area to make drainage waters safer for aquatic life and a marine habitat. It was found that no more than 6% of the farm area could be used to reduce the concentrations in drainage waters from 50 µg/l to less than 1 µg/l for the three herbicides. %> http://jast.modares.ac.ir/article-23-285-en.pdf %P 125-134 %& 125 %! %9 %L A-10-1000-210 %+ %G eng %@ 1680-7073 %[ 2003