Impact of NPK, Plant Residue, Soil Type, and Temperature on the Half-Life of Atrazine Herbicide

Laboratory experiments were conducted to investigate the effects of NPK fertilization, soil type (silty clay and sandy loam) with no history of pesticides application, temperature (28 and 40C°) and maize residue on half-life reduction of atrazine herbicide. The NPK fertilizer was applied at 375 mg N, 187.5 mg P and 187.5 mg K per 600 g soil, while Maize straw was added at rates 12 g/ 600g soil. Atrazine was applied in four concentrations; 0.0678, 1.69, 3.39 or 5.08 mg g-1 soil. The residual atrazine concentration was measured using gas chromatography over a 150-day period. The results showed that degradation of atrazine was highest in Algeraif soil incubated at 40°C (87%), followed by Algeraif soil incubated at 28°C (68%), and Gerif soil at 28°C (54.2%).". Addition of NPK and maize straw significantly enhanced atrazine degradation, with degradation reaching 97% at an at atrazine concentration of 0.0678 mg g-1 soil after 150 days. The lowest half-lives compared to control were 125, 39, 25,19 and 14 days with the application of Gerif soil (28 C°), Algeraif soil (28 C°), Algeraif soil (40 C°), NPK and maize straw respectively at atrazine concentration of 5.08 mg g-1 soil. In conclusion, the addition of NPK fertilizer and maize straw significantly improved the degradation of atrazine, reducing both its concentration and half-life in soil.