Tham khảo tài liệu 'herbicides environmental impact studies and management approaches part 2', khoa học tự nhiên, công nghệ sinh học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Evaluation of Toxicities of Herbicides Using Short-Term Chronic Tests of Alga Daphnid and Fish 9 2009 MEC pg L A B C D E F G Dimethametryn Pretilachlor - Bromobutide Carbetamide - - - - Bendiocarb - - - - Triazine - - - - - - - Cyanazine - - - - - - - Simetryn - - - - - - - Esprocarb - - - Mefenacet - - - not detected in the field. a 2010 MEC pg L H I J K L M N N 30d after Dimetha -metryn - - - Pretilachlor - - - - - - - - Bromobutide Carbetamide - - - - - Bendiocarb - - - - - - - - Triazine - - - - - - - - Cyanazine - - - - - - - - Simetryn - - - - - - Esprocarb - - - - - - - - Mefenacet - - - - - - - - not detected in the field. b Table 3. Actual concentrations of herbicides in the water samples by the simultaneous analysis MEC Measured Environmental Concentrations in 2009 a and 2010 b . 10 Herbicides - Environmental Impact Studies and Management Approaches Mefenacet Esprocarb Simetryn Cyanazine Triazine Bendiocarb Carbetamide Bromobutide Pretilachlor Dimethametryn sites Fig. 3. Actual concentrations of herbicides in each sampling spot. The risk evaluation of each spot based on the field measurements Applying ecological toxicity data of 10 herbicides a risk evaluation based on the MEC of each spot was performed. MEC NOEC was calculated with the species that showed lowest NOEC for each target substance used in the present study shown in Table 4 and Fig 4 . When the MEC NOEC ratios of each herbicide are simply tallied the total sums exceeded 1 in three spots D E and G . Yet from the results of Table 1 ecological effects at nine spots A B C D E F G L and N are reported to be present. From the results of Table 4 at least at spots D E and G the ecological effect of the pesticide which was .
