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近年来,随着大量使用拟除虫菊酯类杀虫剂,导致的环境问题已得到广泛关注.为认识巢湖流域氯菊酯在环境中的赋存状态、迁移转化、环境归趋和生态风险,本研究结合多介质归趋模型和物种敏感性分布模型(SSD),模拟了稳态假设下氯菊酯在巢湖生态系统各环境介质中的浓度分布、迁移通量和去除途径,并通过灵敏性分析和不确定性分析对各输入参数进行了评价.进一步构建污染物的SSD模型,评价了氯菊酯在稳态条件下的潜在生态风险,预测了保护系统中95%的物种时允许最大年输入量.结果表明,氯菊酯在大气相、水体相、沉积物相中的浓度分别为3.99×10~(-16)、5.63×10~(-11)和1.95×10~(-5)mol·m~(-3),沉积物是氯菊酯的最大储库;大气中的氯菊酯主要以挥发形式进入,通过空气颗粒物干沉降消减;水体中的氯菊酯主要以平流输入为主进入,通过底泥沉降消减;沉积物中的氯菊酯主要以底泥沉降形式进入,通过底泥再悬浮和掩埋消减.此外,SSD模型预测的HC5浓度为0.97 ng·L~(-1),假设稳态下预测的水体浓度远低于该值,仅对巢湖流域0.77%的物种产生影响,当年输入量低于78.2 t的情况下,巢湖水体中95%的物种不会受到氯菊酯的威胁.
In recent years, with the extensive use of pyrethroid insecticides, the environmental problems caused by it have drawn much attention.In order to understand the occurrence, migration and transformation, environmental fate and ecological risk of permethrin in the environment of Chaohu Lake Basin, Based on the model of multi-medium fate and the model of species sensitivity distribution (SSD), the concentration distribution, migration fluxes and removal pathways of permethrin in various environmental media of Chaohu Lake ecosystem under simulated steady state hypotheses were simulated. Through sensitivity analysis And uncertainty analysis were used to evaluate each input parameter.Furthermore, an SSD model of pollutants was constructed to evaluate the potential ecological risk of permethrin under steady-state conditions, and the maximum annual input allowed when 95% of the species in the system was protected The results showed that the concentrations of permethrin in the atmospheric, water and sediment phases were 3.99 × 10 ~ (-16), 5.63 × 10 ~ (-11) and 1.95 × 10 ~ (-5) mol · M ~ (-3). The sediment was the largest reservoir of permethrin. Permethrin in the atmosphere mainly entered in volatile form and was diminished by the dry sedimentation of airborne particles. Permethrin in water was mainly dominated by advection Entry, subsidence by sediment subsidence; Permethrin in sediments The sediment concentration of HC5 was 0.97 ng · L -1, and the predicted concentration of HC in the steady state was much lower than this value, Only affects 0.77% of the species in the Chaohu Lake Basin. When the input was less than 78.2 tons in that year, 95% of the species in Chaohu Lake would not be threatened by permethrin.