State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
Environ Pollut. 2020 May;260:114112. doi: 10.1016/j.envpol.2020.114112. Epub 2020 Jan 31.
Veterinary antibiotics have been detected as contaminants of emerging concern in soil environment worldwide. Animal manure is frequently applied to agricultural fields to improve soil fertility, which can result in introducing large amount of antibiotics into soil environment. However, few attempts have been made to identify the spatial and temporal dynamics of veterinary antibiotics in soil at the hillslope scale with different land uses. This study was performed to explore the pattern and variability of veterinary antibiotics in the soil in response to rainfall events. Results showed that higher concentrations of veterinary antibiotics were generally found in cropland (292.6 ± 280.1 ng/g) and orchard (228.1 ± 230.5 ng/g) than in forestland (13.5 ± 9.9 ng/g). After rainfall events, antibiotics accumulated in the soil at the positions where manure was applied, especially under high-intensity rainfall conditions. However, the antibiotic concentration in soil slightly increased from the top to the bottom of hills, thus indicating the restricted contribution of runoff to antibiotic transport, especially under low-intensity rainfall conditions. In addition, most antibiotics were sequestered in the surface soil (0-10 cm), and higher antibiotic concentrations were observed in deep soil (20-40 cm) in cropland than orchard. The soil aggregate, organic matter, and clay content played important roles in antibiotic sequestration along the hillslope subject to low-, medium-, and large-amount rainfall events, respectively. This study identified that land use, rainfall conditions, and soil structures jointly affect the spatial and temporal variability of antibiotics in soils on hillslopes.
兽用抗生素已被发现是全球土壤环境中新兴关注的污染物。动物粪便经常被施用于农田以提高土壤肥力，这可能导致大量抗生素进入土壤环境。然而，很少有人试图确定不同土地利用方式下山坡尺度上土壤中兽用抗生素的时空动态。本研究旨在探讨土壤中兽用抗生素对降雨事件的响应模式和可变性。结果表明，农田（292.6±280.1ng/g）和果园（228.1±230.5ng/g）中兽用抗生素的浓度通常高于林地（13.5±9.9ng/g）。降雨事件后，抗生素在施粪肥的位置积累在土壤中，特别是在高强度降雨条件下。然而，抗生素在土壤中的浓度从山顶到山脚略有增加，这表明在低强度降雨条件下，径流对抗生素运移的贡献有限。此外，大多数抗生素被截留在表层土壤（0-10cm）中，农田中深层土壤（20-40cm）中的抗生素浓度较高。在低、中、大量降雨事件中，土壤团聚体、有机质和粘粒含量分别在山坡上的抗生素截留中起着重要作用。本研究确定了土地利用、降雨条件和土壤结构共同影响山坡土壤中抗生素的时空变异性。
