鄱阳湖持久性有机污染物(POPs)长距离传输潜力模拟

Simulation of Long-Range Transport Potential of POPs in Poyang Lake

利用TaPL3模型模拟研究了鄱阳湖5种典型持久性有机污染物(POPs)的长距离迁移潜力(LRTP)和总持久性(Pov),比较了不同污染物特征迁移距离(CTD)和Pov的大小,并以p,p’-DDT为例对关键参数进行了灵敏度分析.结果表明,p,p’-DDT、γ-HCH、HCB、PCP和2,3,7,8-TCDD排放到大气中,特征迁移距离(CTDAir)在432 km(2,3,7,8-TCDD)~86479 km(HCB)之间,总持久性(PovAir)在85.6 d(PCP)~2231 d(HCB)之间,土壤相是POPs的主要归宿,约占72.0%;排放到水体中,特征迁移距离(CTDWater)在4207 km(PCP)~1.19×105km(γ-HCH)之间,总持久性(PovWater)在103 d(PCP)~2890 d(HCB)之间,沉积物相是POPs的主要归宿,约占52.5%.环境介质中的半衰期和辛醇-水分配系数的对数是影响污染物CTD和Pov的主要理化性质参数.与同类研究相比,相关POPs在鄱阳湖的CTDAir处于中间水平,但CTDWater偏高,这与鄱阳湖的水体深度和水体流速这两个对CTDWater影响显著的参数较其它研究区域高有关.研究结果可为该地区POPs的环境过程及环境风险的研究提供科学依据.

The long-range transport potential( LRTP) and overall persistence( Pov) of 5 typical persisitent organic pollutants( POPs)through air and water in Poyang Lake were estimated by the TaPL3 model. The characteristic travel distance( CTD) and Pov of different POPs were compared. In addition,the key parameters were examined by the sensitivity analysis method using p,p'-DDT as an example. The results showed that the CTDAirof p,p'-DDT,γ-HCH,HCB,PCP and 2,3,7,8-TCDD ranged from 432 km( 2,3,7,8-TCDD) to 86 479 km( HCB),and the value of PovAirranged from 85. 6 d( PCP) to 2 231 d( HCB),when POPs were emitted to the atmosphere. Soil phase was the main fate of these typical POPs,and it was about 72. 0% percent of the total phase. Meanwhile,the CTDWaterwas from 4 207 km( PCP) to 1. 19 × 105km( γ-HCH),and PovWaterwas from 103 d( PCP) to 2 890 d( HCB),when POPs were emitted to the water. Sediment phase was the main fate of these typical POPs,and it was about 52. 5% percent of the total phase.Half-life in the environment and octanol-water partition coefficient logarithm of POPs were the two main physical-chemical parameters that affected CTD and Pov. When compared with other similar studies in China,the CTDAirof related POPs in Poyang Lake is in the middle level. While the CTDWaterwas a little higher than other areas,which was due to the higher water depth and water flow velocity of Poyang Lake. Therefore,the higher water depth and water flow velocity were two significantly-affected parameters of CTDWater. The results could provide a scientific basis to studies of environmental process and risks of POPs in Poyang Lake.