| Atrazine has 60 years of production history of use in the world, it has been widely used worldwide. United States was at first rank in using of atrazine in the world, the annual amount of more than 30000 t. Because the United States Environmental Protection Agency(EPA) had thought that the use of atrazine economic benefits far outweigh its possible negative effects, it does not prohibit its use. Therefore, more and more herbicide because of security issues has been questioned and was prohibited under the en vironment of use, usage of atrazine increased year by year. European countries such as France and Germany was the first country to use as a herbicide atrazine, the early 1960 s to the 1990 s, atrazine usage rapid increase in Europe. In 1991 the Many scientis t detected atrazine in Germany and other parts of world tap water for several years, Studies found that atrazine concentration in water was increased year by year, the majority of water samples had a major metabolite of atrazine product. Over the same period, for the Detection of Paris groundwater DEA content of a seven-year French scientists found that Paris groundwater have been more than the parent atrazine content. Europe was the region earlier to reduce the use of atrazine, along with its related research and in-depth understanding of the harm, as well as new low-toxic alternative products gradually come out, and the progressive development of ecological agriculture, to the late 90 s of the last century, Europe has to gradually reduce and eliminate relia nce and use of atrazine.Present study was conducted to observe safe method for atrazine removal from soil and divided in two main parts. First was to see soil p H and temperature influence on different atrazine bioremediation techniques and second was app lication of different bioremediation techniques to study their impact on atrazine degradation. For this purpose sodium citrate, Arthrobactor sp. Strain DNS10, sawdust and animal manure was selected to see their atrazine remediation efficiency under p H 5, 7 and 9 and temperatures 20, 30, and 40 oC respectively. Results concluded that atrazine remediation was generally optimized at p H 7 and 30 oC for all treatments except sodium citrate as soil treated with SC was not temperature dependant but at p H 5 remediation process was determined slower. Atrazine remediation in soil with no additional amendment was only 34% while in soil treated with Sawdust, DNS10, sodium citrate and animal manure was 75.17, 89, 74.17, and 76.83 % at optimized p H and temperature. Overall atazine removal rate was significantly(≥0.01) higher with increase in temperature at all selected p H. Different bioremediation strategies(Natural attenuation, bio-augmentaion, bio-stimulation and bioaugmentaion+biostimulation) were adopted to measure atrazine biodegradation potential of sodium citrate, sawdust, animal manure and Arthrobactor sp.strain DNS10 solely and in combination. For this purpose initial atrazine concentration mixed in soil was double than normal application in field. Arthrobactor sp.strain DNS10(bioaugmentaion) remediated 79% of atrazine while animal manure, sawdust and sodium citrate(biostimulation) degraded 74-74.4% of atrazine. when contaminated soil was treated with combined bioaugmentaion and stimulation; atrazine remediatio n potential was increased 74 to 84%. Addition of two nutrients alongwith Arthrobactor sp.strain DNS10 significantly(≥0.05) enhanced its degradation ability as compared to single nutrient. Highest bioremediation rate(88.5%) was observed in soil microcosm treated with mix animal manure, sodium citrate and Arthrobactor sp.strain DNS10. |
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