Monitoring of some herbicides used at sunflower agriculture under natural conditions and removal via bioremediation method

The study of this thesis is about the removal of Trifluralin banned by Ministry of Republic of Turkey Ministry of Food, Agriculture and Foodstock in 2013 and the Aclonifen suggested. These herbicides are used at Thrace region of Turkey that supplies most of the sunflower need. Studies were carried out at fields where these two herbicides used. In one year period, monthly soil samples were taken from targeted points and Trifluralin and Aclonifen residual amounts were determinated. Some bacteria and fungi were isolated from soil samples taken from these areas for their identifications before the use of herbicide. Removal efficiencies of these herbicides were determined by microbiological degradation with these produced bacteria and fungi in liquid and solid media. With these growing bacteria and fungi, removal rate by bioremediation method studies were carried out. In addition to microbial degradation mechanism, other mechanisms like adsorbtion (with desorbtion) and photolysis effects were also studied to show the degradation of these two herbicides by isolated microorganisms with the measurements of the turbidity and the numerical value (colony number). As a results of one year period studies, persistence of Trifluralin seems to be partially higher then Aclonifen (%15 - %11). Aclonifen was determined to be more rapidy photolized than Trifluralin at day light in photolysis studies. Bioremediation study results have shown differences with respect to species in liquid media, Best removal efficiencies were obtained with the mix culture of bacteria and fungi. According to the bioremediation studies in soil media, removal rate of Aclonifen was determinated to be higher than Trifluralin. Increasing microorganism concantration has led to the increment of bioremediation rate paralelly (with 10 ml of mixed cultures for Aclonifen, in 5 week as 97%, for trifluralin in 9 week as 99%). As a results of adsorbtion studies, adsorbtibility rate of Trifluralin was determinated to be higher then Aclonifen. Degradation time of these herbicides in liquid culture media with isolated bacteria and fungi varied between 5min. and 135 min.