【作者】 Naveedullah（纳维德）；

【导师】 陈英旭； 沈超峰；

【作者基本信息】 浙江大学 ， 环境工程， 2014， 博士

【摘要】 农业流域的重金属与农药、激素等有机物的污染有其自身特征,但目前此方面的研究较少。本论文研究了我国东南部典型农业流域——苕溪流域及其四岭水库小流域土壤、水体中重金属与农药、激素等有机物污染情况,并评估了污染的健康风险,具体研究内容导结果如下：本论文首先通过在线水质监测系统研究了2011年9月至2012年9月四岭水库的基本水质特征,计算了综合水质指数WQI(包含10种参数：pH、水温、EC、DO、浊度、TDS、CODMn、TP、TN和NH4+-N)和WQImin (包含5种参数：pH、水温、EC、DO和浊度)。采用相关性分析及冗余分析比较了WQI和WQImin,结果表明秋季和冬季时四岭水库的水质良好,春季和夏季时水质则逐渐变差。WQImin和WQI所反映的水质变化趋势一致(R2为0.99),而分析WQImin所需的指标少、成本低,故WQImin更适用于淡水库的水质监测。在冬季时,WQI与DO呈显著正相关。此外,结果显示该水库有爆发水华的风险,气候条件是影响水库水质的重要因素。本研究表明WQI可以提供有价值的信息,为地表水资源开发、地表水水质监测提供管理决策依据。采集四岭水库流域农田土壤,测定7种重金属元素Zn、Cu、Mn、Fe、Cr、Cd和Pb的含量。采用多元统计分析法分析冬季和夏季土壤中重金属元素含量的变化,并评估了土壤的污染状况。研究发现冬季土壤中大部分重金属的浓度高于夏季,而Cr和Cd的季节分布则较为随机。主成分分析及聚类分析结果表明人类活动显著影响土壤中Zn、Cd、Pb、Cr和Cu的分布。Zn、Cd和Pb的富集系数(EF)较高,而地质累积指数(Igeo)和污染系数(Cf)则显示土壤中Zn、Cr、Cd和Pb达到了中污染到高污染程度。采集四岭水库流域地表水样,分析Zn、Cu、Mn、Fe、Cr、Cd和Pb的时空变化规律,并评价其风险。夏季水体中Mn、Fe和Cd的浓度较高。而到冬季,Zn、Fe和Pb则是水体中主要的重金属污染物。在这两个季节中,Cr的浓度均比较高。根据重金属的危害商(HQing)和危害指数(HIing)可知,经口摄入导致的非致癌风险已接近临界值。在夏季,金属元素的长期每日摄入量依次为Cr> Fe＞Mn>Zn>Cd;而在冬季长期每日摄入量依次为Zn>Fe>Cr>Pb>Mn>Cu;其中Cr、Cd和Pb经摄入途径产生的致癌风险高于允许临界值(10-6)。主成分分析及聚类分析结果表明人类活动和自然作用均是导致水体污染的重要因素。调查分析了不同季节里四岭水库流域农田土壤中有机氯农药(OCPs)、多环芳烃(PAHs)及多氯联苯(PCBs)的含量,发现几乎所有被调查的土样中均存在此类持久性有机污染物(POPs)。从夏季到冬季,OCPs、PAHs和PCBs浓度变化范围分别为21.85～21.64ng g-1、40.33～38.83ng g-1及86.98～74.29ng g-1。依据每种POPs的浓度,评估了当其通过摄食、皮肤接触或吞入途径进入人体所造成的致癌风险,最终结果表明四岭水库流域土壤中OCPs、PAHs或PCBs的单一致癌风险较低。但以这3类POPs的总浓度为评估依据时,发现其所产生的致癌风险略高于允许临界值(10-6),达到了1.07×10-6。调查了苕溪流域中临近四岭水库的某万头养猪场废水中雌激素水平,并分析了厌氧/好氧活性污泥(A/O)污水处理工艺和升流式厌氧污泥床-分步进水序批式反应器(UASB-SFSBR)丛理工艺对雌激素的去除效果。液相色谱-串联质谱(LC-MS/MS)检测结果表明A/O污水处理工艺无法有效的去除水体中的雌激素,而UASB-SFSBR对水体中雌激素的去除率高达78%。雌激素酵母筛选实验(YES)结果显示经UASB-SFSBR处理后,水体中17β-雌二醇活性当量可从初始的31.5ngL1降低至检测限以下。化学检测方法和生物检测方法所得出的雌激素去除率并不一致。应提高养猪场废水中雌激素的去除率,以降低其对环境造成的潜在危害。对苕溪流域包括四岭水库小流域水体中的雌激素水平进行了调查。LC-MS/MS法仅检测到了一种雌激素,即雌酮,而其它大部分雌激素均未检出。在所抽检的水样中,雌酮的浓度范围为低于检测限至17.25ng L-1。采用YES法检测水样中的雌激素活性,发现所有被检水样中均有17β-雌二醇活性,其中太湖入湖口水样中17β-雌二醇活性当量为17.60ng L-1。因此把化学检测技术与生物检测技术相结合,将有助于更加有效的检测与分析环境中的雌激素。综上所述,苕溪流域中的雌激素污染必须加以控制。更多还原

【Abstract】 In agricultural watersheds, the pollution of heavy metals, pesticides, and estrogens has special characteristics. However, related research is lacking. In this study, we moni-tored pollution and assessed the risk of heavy metals and organic pollutants in soil and wa-ter from typical agricultural watersheds in southeast China, Tiaoxi River and Siling reser-voir. The results and conclusion can be summarized as follow:In this study, the water quality index (WQI) of Siling reservoir was verified to calcu-late scores based on water characteristics data using an online water quality monitoring system from September2011to September2012. WQI (including ten parameters:pH, WT, EC, DO, TDS, CODm,,, TP, TN, NH4+-N, and turbidity) and a minimal water quality index (WQImin)(including five parameters:water temperature, pH, DO, EC and turbidity) were investigated. Multivariate statistical analysis techniques viz:correlation analysis and re-dundancy analysis (RDA) were employed to analyze the obtained data. The results showed that water quality was good in the Siling reservoir during autumn and winter sea-sons. However, a decreasing trend in water quality was observed during spring and sum-mer seasons. WQImin illustrates similar trend to WQI with a better R2value of0.99, with a minimum cost and could be useful for the intervallic routine monitoring program. Higher positive correlation between WQI and DO was observed during winter season. Moreover, the results further indicated the risk of algal blooms in the reservoir water, which reflected the effects of climatic condition on reservoir water quality. This study suggested that the resulting WQI provides valuable information on developing, monitoring and understand-ing surface source water quality for the decision makers and reservoir management.The concentrations of seven metals (Zn, Cu, Mn, Fe, Cr, Cd and Pb) were deter-mined in agricultural soils from Siling reservoir watershed. Multivariate statistical ap-proaches were used to study the variation of metals in soils during summer and winter sea-sons. Heavy metal concentrations were observed higher in winter season as compared to summer season. Cr and Cd revealed random distribution with diverse correlations in both seasons. Principal component analysis and cluster analysis showed significant anthropo-genic intrusions of Zn, Cd, Pb, Cr and Cu in the soils. Enrichment factor, revealed signifi- cant enrichment of Zn, Cd and Pb, whereas, geoaccumulation index and contamination factor exhibited moderate to high contamination for Zn, Cr, Cd and Pb.Spatio-temporal variations and risk assessment of the selected heavy metals (Zn, Cu, Mn, Fe, Cr, Cd and Pb) were investigated in water samples from Siling reservoir wa-tershed. During summer season Mn, Fe and Cd concentrations were higher in the water samples, while the concentrations of Zn, Fe and Pb were dominant in winter season. How-ever, Cr exhibited elevated concentrations in both seasons. The health risk assessment re-vealed that hazard quotient (HQing) and hazard index (HIing) values were near to the ac-ceptable limit indicating non-carcinogenic risk to the recipient via oral intake of water. The calculated values for chronically daily intake were found in the order of Cr> Fe> Mn> Zn> Cd in summer season and Zn> Fe> Cr> Pb> Mn> Cu during winter season. The carcinogenic risk (CRing) via ingestion route for Cr, Cd and Pb were noted higher than the acceptable limit (10-6). Multivariate statistical analysis such as; cluster analysis (CA) and principal component analysis (PCA) results revealed that both natural processes and an-thropogenic activities were the main sources of water contamination.Seasonal concentrations of legacy organochlorine pesticides (OCPs), polycyclic aro-matic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) were determined in soil samples from agricultural fields of the Siling reservoir watershed. Persistence organic pollutants (POPs) were found in almost all of the soil samples. The total concentrations of OCPs, PAHs, and PCBs during summer and winter seasons ranged from21.85to21.64ng g-1,40.33to38.83ng g-1, and86.98to74.29ng g-1, respectively. The total concentrations of individual POPs were further used to evaluate the cancer risk probabilities in human via ingestion, dermal contact, and inhalation of soil particles. Near to very low cancer risk of every POPs was found in the soils of the Siling reservoir watershed. Furthermore, cancer risk, based on total OCPs, PAHS and PCBs concentrations were also investigated. Results revealed cancer risk with a value of1.07×10-6, which was a little higher than the ac-ceptable limit (10-6).Estrogens levels in wastewater collected from a large-scale swine farm in Tiaoxi River watershed near by Siling reservoir were analyzed. And the efficiency of estrogen removal by anaerobic/aerobic active sludge (A/O) treatment or by upflow anaerobic sludge blanket and step-fed sequencing batch reactor (UASB-SFSBR) treatment was also investigated. The results showed that the A/O treatment had no significant estrogenic re-moval ability, whereas the removal rates of estrogen after UASB-SFSBR treatment reached approximately78%, as measured by LC-MS/MS. The17β-estradiol equivalents (EEQ) decreased from31.5ng L-1to an undetectable level according to the Yeast Estro-gen Screen (YES) analysis. We found differences between the estrogen removal rates measured by the chemical assay and those measured using the bioassay. More attention must be paid to the removal of estrogen pollutants in livestock wastewater to reduce the environmental risk.The estrogen pollution in surface water of Tiaoxi River watershed was investigated by chemical and bioassay analysis. Most estrogens species, except estrone, were not de-tected by the chemical analysis using LC-MS/MS. The concentration of estrone in the samples ranged from below the detection limit to17.25ng L"1. The estrogen activity in most water samples was also determined by YES. The17β-estradiol activity could be de-tected in all water samples. EEQ in sample from the estuary of Taihu Lake was17.60ng L-1. This study demonstrates that combining chemical and bioassay analysis is an effective way to detect environmental contamination by estrogen species. Furthermore, the results indicate that the risk of estrogen contamination in the Tiaoxi River watershed should be controlled.更多还原