藻类对城市河湖PAHs多介质赋存影响的关键因子识别及预测模型研究

Eutrophication, algal blooms and contamination of POPs （persistent organic pollutants）are all the problems of environmental pollution, which usually coexisted in the city waterbody. Many research and mathematic models had been done for each environmental problem, respectively. But there is little research on the relationship among the three factors and the corresponding prediction model, it can not meet the demand of prediction for the natural water. Therefore, it has very important theoretical significance and practical value to collaborative research these three kinds of water environmental problems. This study intends to make ecology contribute of algal, which has a significant impact on occurrence characteristics of PAHs in multimedia environment, as a breakthrough point of the research, emphasizes the effect of algae composition and biomass growth on PAHs occurrence in multimedia environment. Based on the field measured data and the technology of computer data mining and numerical simulation, construct the algae growth prediction model with algae composition - specificity and eutrophication degree classification from the macroscopic scale. Using the technologies of ecological sorting and redundancy analysis, identify the key habitat and dominant algae with the most significant influence on the migration and transformation of PAHs. By means of parameter transformation module and the source code modifying, couple the algae growth model and multimedia fugacity model, construct the multimedia prediction model for PAHs that applicable to different eutrophication degree waterbody, compare the ecological contribution of algae, and put forward the best chance to remove PAHs in waterbody. Reveals the important role of algae in water self-purification process in a deeper level, and enhance the level of water quality simulation and process evolution.

富营养化、藻华和持久性有机污染是目前城市水体普遍共存的环境问题，人们已分别对其进行过研究，但对三者间关系及相应模型研究却很少，无法满足人们精确预测预报需求。因此，协同研究这三类环境问题其理论和实际意义十分重要。本研究拟以能对水体中PAHs多介质赋存产生重大影响的藻类生态贡献为研究切入点，强调藻类组成及生物量增长对PAHs赋存的影响。利用实测数据及计算机数据挖掘和数值模拟，从宏观尺度构建具有藻类组成特异性及水体富营养化程度分级的藻类生长预测模型；利用生态排序及冗余度分析，识别对PAHs运移影响最显著的关键生境及优势藻类；借助参数转化模块和源代码改写，将藻类生长模型与多介质环境逸度模型耦合，构建适用于不同富营养化水体中藻类影响下的PAHs多介质赋存预测模型，并比较藻类生态贡献，提出除去城市水体中PAHs的最佳时机，在更深层面上揭示藻类在水体自净中的重要作用，提升水质演化及过程模拟的研究水平。

富营养化、藻华和持久性有机污染是城市水体普遍共存的环境问题，人们已分别对其进行过研究和建模。但对三者间关系及相应模型研究却很少，无法满足人们精确预测预报需求。因此，协同研究这三类环境问题其理论和实际意义十分重要。本研究拟以能对水体中PAHs多介质赋存特征产生重大影响的藻类生态贡献为研究切入点，强调藻类组成及生物量增长对PAHs赋存的影响。利用实测数据及计算机数据挖掘和数值模拟，从宏观尺度构建具有藻类组成特异性的藻类生长预测模型；利用生态排序及冗余度分析，识别出对PAHs运移影响最显著的关键生境及优势藻类。结果表明，富营养化介导下的水中藻类组成具有明显的温度和营养盐依变特征，如春季水体属于硅藻-绿藻型，夏季属于蓝藻-绿藻-硅藻型，秋季属于蓝藻-硅藻型，而冬季水体为硅藻型；PAHs在研究区域城市水体中的赋存也具有明显的季节性和环数依变特征。而且蓝藻、裸藻以及大部分的绿藻和硅藻对Ace和Nap这些低环PAHs具有较好的富集能力；而硅藻门的冠盘藻属、波缘藻属和绿藻门的纤维藻属则对Flu、BaP、Ant、Chr、DahA、BaA、BghiP、Phe这几种低到高环的PAHs的富集生态贡献能力较好。本研究以Level III模型为基础，以城市多介质逸度模型为骨架，结合南京地理和气象信息等条件，构建的三级稳态多介质城市区域7箱（气、有机膜、土壤、沉积物、水体、水中藻类和植被）逸度模型，与基于富营养化程度优化的藻类生长模型耦合后，适用于不同富营养化程度水体中藻类影响下的PAHs多介质赋存预测，并重点比较了藻类的生态贡献，提出了除去城市水体中PAHs的最佳时机，在更深层面上揭示藻类在水体自净过程中的重要作用，提升水质演化及过程模拟的研究水平。