基于铜锈环棱螺的生物炭修复沉积物中BDE-47生物积累动力学预测模型

研究了铜锈环棱螺对沉积物颗粒的摄取速率、从水和沉积物中摄取BDE-47的效率，以及在BDE-47污染沉积物中添加玉米秸秆生物炭后对这些生理学参数和间隙水中BDE-47平衡浓度的影响.构建了基于铜锈环棱螺摄取和消除BDE-47的相关生理学参数和沉积物地球化学参数的生物动力学预测模型，同时评价了该模型预测BDE-47生物积累的效力.结果显示，铜锈环棱螺对沉积物的摄食率为6.04 g·g^-1·d^-1，对水中BDE-47的摄取效率为38.41%.在BDE-47污染沉积物中添加4%的玉米秸秆生物炭（CSB）可以显著降低间隙水中BDE-47的平衡浓度，降幅达到81%.铜锈环棱螺对添加CSB的沉积物中BDE-47的生物积累显著低于未添加CSB的沉积物，暴露28 d后，添加CSB的沉积物中BDE-47的生物积累下降了66%.本研究构建的生物动力学模型的预测结果与暴露测试中观察到的铜锈环棱螺对BDE-47的摄取情况基本一致.BDE-47的28 d生物积累对沉积物颗粒摄食率、从沉积物中摄取BDE-47的效率、沉积物中BDE-47的浓度和BDE-47的消除速率常数等4个参数的响应表现出较好的敏感性.根据模型的预测，铜锈环棱螺从沉积物中摄取的BDE-47占总积累量的80%以上.当沉积物中添加CSB后，模型显示出更好的预测效力.因此，在已知沉积物和间隙水中BDE-47浓度的前提下，利用该模型可以有效地预测铜锈环棱螺体内BDE-47的积累量，从而减少沉积物生态毒性风险评价和利用生物炭进行原位修复效果评估的不确定性.

Biodynamic model to predict BDE-47 accumulation by Bellamya aeruginosa from sediment amended with biochar

The sediment particle ingestion rate, BDE-47 uptake efficiency of Bellamya aeruginosa from water and sediment, and the effects of corn straw biochar (CSB) amendment to the BDE-47-contaminated sediment on these physiological parameters and the porewater BDE-47 equilibrium concentration were characterized. A biodynamic prediction model based on the physiological parameters involving uptake and elimination of BDE-47 by B. aeruginosa and sediment geochemical parameters was established and the effectiveness of this model for predicting of BDE-47 bioaccumulation was evaluated. The results show that the sediment ingestion rate of B. aeruginosa is 6.04 g·g^-1·d^-1. The efficiency of BDE-47 uptake by B. aeruginosa from water is 38.41%. The CSB (4%) amendment to BDE-47-contaminated sediments can significantly reduce the porewater BDE-47 equilibrium concentration by up to 81%. BDE-47 uptake by B. aeruginosa from the CSB-amended sediment was significantly lower than that in the sediment without CSB. Upon 28 days of exposure, BDE-47 uptake from the CSB-amended sediment was reduced by 66% relative to the sediment without CSB. The biodynamic prediction model established in this study was found to agree well with the observed uptake by B. aeruginosa in the exposure test. The 28 d bioaccumulation of BDE-47 showed good sensitivity to four parameters including the sediment particle ingestion rate, BDE-47 uptake efficiency from the sediment, BDE-concentration in the sediment, and the elimination rate constant of BDE-47. According to the prediction of the model, B. aeruginosa takes up more than 80% of body burden of BDE-47 through sediment ingestion. For the CSB-amended sediment, this model exhibited a better prediction effectiveness. Therefore, given the known BDE-47 concentrations in the sediment and porewater, this model can be used to effectively predict the accumulation of BDE-47 in B. aeruginosa, and thus reduce uncertainties in the assessment of sediment ecotoxicity risk and the evaluation of in-situ remediation effectiveness of biochar.