Herbicide residues and distribution in cropland soils from the black soil region of northeast China
To investigate herbicide residues in cropland from the black soil regions of northeast China,170 soil samples from six typical black soil regions were collected,and 17 herbicides were detected.In general,acetochlor had the highest detection rate(74.7%),and fomesafen had the highest residual concentration(198.88 μg·kg-1).In terms of regions,soil in the Liaoning Province had the most number of herbicides residue types,and soil in the Heilongjiang Province had the highest residual concentration.The herbicides residues in dry lands of Tieling City and Fuxin City were quite similar to those in Changchun City and Siping City,and were significantly different from those in Suihua City.In terms of crop types,a wide variety of herbicides residues were detected in paddy fields,whereas the residual concentration of herbicides in dry land was high.A total of 11 herbicides were detected in paddy fields,and the average residual concentrations of fomesafen in dry lands was high at 68.77 μg·kg-1 and 409.30 μg·kg-1 in maize and soybean fields,respectively.Taken together,our results suggest that geographical location and crop types are important factors that affect herbicide residues in soil.
black soil region in northeast Chinacrop typeherbicidedetection rateaverage residual concentration