Transport of veterinary medicines from soils to groundwater

继续利用土柱和蒸渗仪对兽药的流动和淋洗进行研究，特别强调优先流动。用14C标记的磺胺嘧啶(SDZ)的猪浆制成的蒸渗仪和用14C标记的二氟沙星(DIF)的猪的猪浆制成的蒸渗仪将被破坏性抽样，以获得关于兽药及其代谢物去向的物质平衡。在盆栽试验中使用了蒸渗仪破坏性采样的土壤，以检验包括转化产物在内的结合的SDZ(和DIF)可能通过植物根际的作用而变得可用的假设。土柱试验继续研究重复使用含SDZ的泥浆的效果和14C标记的羟基磺胺嘧啶的去向。利用土柱试验知识，通过数值模型对SDZ在土壤中的运移进行了预测。因此，对不同土层的土壤进行吸附实验是强制性的，因为我们经历了意想不到的吸附行为。此外，我们还将准备和进行中央中观和野外实验。

Studies on the mobility and leaching of veterinary medicines with special emphasis on preferential flow using soil columns and lysimeters are continued. The lysimeters that were manured with pig slurry from pigs medicated with 14C labelled sulfadiazine (SDZ) and the lysimeters that were manured with pig slurry from pigs medicated with 14C labelled difloxacin (DIF) will be sampled destructively in order to obtain material balances on the fate of the veterinary medicines and their metabolites. Soil from the destructive sampling of the lysimeters is used in pot experiments to test the hypothesis that bonded SDZ (and DIF) including transformation products may become available through the action of the plant rhizosphere. Soil columns experiments are continued to study the effect of repeated application of slurry containing SDZ and the fate of 14C-labelled hydroxy-sulfadiazine. The knowledge from the soil column experiments is used to predict the transport of SDZ in soil with a numerical model. Therefore sorption experiments with soil from different horizons are mandatory as we experienced unexpected sorption behaviour. In addition we will prepare and conduct the central mesocosm and field experiment.