Behavior of imidazolinone herbicide enantiomers in earthworm-soil microcosms: Degradation and bioaccumulation
Behavior of imidazolinone herbicide enantiomers in earthworm-soil microcosms: Degradation and bioaccumulation
复制标题
咪唑啉酮除草剂对映体在蚯蚓-土壤微观世界中的行为：降解和生物累积
DOI：
10.1016/j.scitotenv.2019.135476
复制
发表时间：
2020
影响因子：
9.8
通讯作者：
Huihua Tan
中科院分区：
文献类型：
--
作者：
Mingfeng Hu;Kunfeng Liu;Jingsi Qiu;Hui Zhang;Xuesheng Li;Dongqiang Zeng;Huihua Tan
咪唑啉酮类除草剂是一类手性除草剂，广泛应用于农作物杂草防治。尽管对映体在陆地系统中的应用广泛，但对其行为的研究却很少。本研究利用蚯蚓-土壤微观环境，研究了蚯蚓对马扎莫司、马扎哌司和马扎乙哌对映体在土壤中的生物积累及其在土壤中的降解。3种除草剂在蚯蚓体内的生物积累不具有明显的对映选择性。Imazamox和imazethapyr在土壤中的立体选择性降解不显著（p < 0.05），而imazapic的对映选择性降解显著（p < 0.05）。此外，还计算了3种除草剂的生物群对土壤积累因子（BSAF）值。研究了BSAF值与土壤有机质含量的关系。蚯蚓-土壤微观环境中BSAFs值与除草剂的log kows呈负相关，与土壤有机质含量呈正相关。这些关系表明，土壤化学疏水性（Kow）和土壤有机质含量是预测咪唑啉酮类除草剂对蚯蚓生物有效性的良好指标。
Imidazolinone herbicides are a group of chiral herbicides that are widely used to control weeds in crops. Despite their wide use, few studies on the behavior of enantiomers in terrestrial systems have been reported. In this study, the bioaccumulation of imazamox, imazapic, and imazethapyr enantiomers in earthworm and their degradation in soils were assessed using earthworm-soil microcosms. The bioaccumulation of the three herbicides in earthworm was not significantly enantioselective. Imazamox and imazethapyr did not significant stereoselective degradation in soil (p > 0.05), while the enantioselectivity of the degradation of imazapic was significant (p < 0.05). Furthermore, biota to soil accumulation factor (BSAF) values were also calculated for three herbicides. Relationships between BSAF values and organic matter content of soil and log KOWof herbicides were investigated. The BSAFs values were negatively correlated with the log KOWof herbicides, and were positively correlated with organic matter content of soil in earthworm-soil microcosms. These relationships indicated that chemical hydrophobicity (Kow) and organic matter content of soil were good predictors to estimate the bioavailability of imidazolinone herbicides to earthworm.