Persistence of the herbicide butachlor in soil after repeated applications and its effects on soil microbial functional diversity |
| |
Authors: | Hua Fang Yun L. Yu Xiu G. Wang Xiao Q. Chu Xiao E. Yang |
| |
Affiliation: | 1. Department of Plant Protection, College of Agriculture &2. Biotechnology , Zhejiang University , Hangzhou, China;3. MOE Key Lab of Environment Remediation &4. Ecosystem Health, College of Environmental and Resource Sciences , Zhejiang University , Hangzhou, China |
| |
Abstract: | Effects of repeated applications of the herbicide butachlor (N-(butoxymethyl)-2-chloro -N-2′,6′-dimethyl acetanilide) in soil on its persistence and soil microbial functional diversity were investigated under laboratory conditions. The degradation half-lives of butachlor at the recommended dosage in soil were calculated to be 12.5, 4.5, and 3.2 days for the first, second, and third applications, respectively. Throughout this study, no significant inhibition of the Shannon-Wiener index H′ was observed. However, the Simpson index 1/D and McIntosh index U were significantly reduced (P ≤ 0.05) during the initial 3 days after the first application of butachlor, and thereafter gradually recovered to a similar level to that of the control soil. A similar variation but faster recovery in 1/D and U was observed after the second and third Butachlor applications. Therefore, repeated applications of butachlor led to more rapid degradation of the herbicide, and more rapid recovery of soil microorganisms. It is concluded that repeated butachlor applications in soil had a temporary or short-term inhibitory effect on soil microbial communities. |
| |
Keywords: | Biolog butachlor herbicide microbial diversity soil |
|
|