限制分配模型预测黑麦草吸收PAHs

采用水培体系检验了限制分配模型预测黑麦草同时吸收苊、芴、菲和芘4种多环芳烃(PAHs)的准确性.结果表明,限制分配模型能够较好地预测黑麦草吸收积累PAHs的程度.但由于该模型仅考虑根部传输,忽略了叶面吸收,导致模型对茎叶中PAHs含量预测的准确性较差.根系和茎叶的预测误差(预测值与实测值之差除以实测值的百分数)分别小于57.4%和98.5%.若考虑叶面吸收对模型预测的影响,则能显著降低茎叶中4种PAHs的预测误差.由于叶面吸收的影响随PAHs脂溶性升高而增大,预测误差降低程度为芘>菲>芴>苊,其中芘的最大预测误差由98.5%下降至69.4%.

Prediction of PAHs Uptake by Ryegrass with a Partition-Limited Model

The performance of a partition-limited model on prediction of four PAHs(acenaphthene,fluorene,phenanthrene and pyrene) uptake by ryegrass simultaneously was evaluated using a hydroponic system.Results suggest that the model has a good performance on prediction of PAHs uptake.However,the model focused on root translocation only,while excluded foliar uptake,which resulted in a poor performance on prediction of PAHs in shoots.The differences of simulated and experimented concentrations of PAHs were less than 57.4% for roots and less than 98.5% for shoots respectively.If the influence of foliar uptake on the performance of the model was taken into account,the differences for all the four PAHs would be reduced significantly.Since the influence of foliar uptake increased with the increase of the hydrophobic property of the PAHs,the differences decreased with an order of pyrene> phenanthrene> fluorene> acenaphthene,among which the maximum difference for pyrene decreased from 98.5% down to 69.4%.