人工湿地中几种常见水生植物氨氮耐受性试验研究

选择人工湿地中常用的6种水生植物(美人蕉、菖蒲、香蒲、芦苇、凤眼蓝和睡莲)为受试植物,进行氨氮耐受性试验。在人工培养条件下配置不同氨氮浓度的营养液对这6种植物进行培养,一定时间后,对植物的抗氧化酶防御系统主要酶学指标进行测试。通过测定植物叶片中丙二醛(MDA)含量、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活性变化,找出6种水生植物的氨氮耐受性规律。结果表明：(1)菖蒲的SOD活性在氨氮浓度为300 mg/L左右时达到峰值,凤眼蓝、香蒲、睡莲的SOD活性峰值均在氨氮浓度为500 mg/L左右时出现,美人蕉和芦苇的SOD活性峰值出现在600 mg/L以后,且前期呈稳定增长;(2)凤眼蓝、睡莲、香蒲、菖蒲的CAT活性峰值均在氨氮浓度为500 mg/L左右出现,且前期都呈稳定增长,美人蕉和芦苇的CAT活性峰值在氨氮浓度为600～700 mg/L时出现,其中芦苇呈稳定增长,美人蕉呈先减后增的趋势;(3)凤眼蓝和睡莲的MDA在氨氮浓度为300 mg/L左右时达到峰值,香蒲和菖蒲的MDA在氨氮浓度为500 mg/L左右时出现峰值,美人蕉和芦苇的MDA峰值在氨氮浓度为600 mg/L以后出现;(5)菖蒲、凤眼蓝、芦苇、睡莲适用于低浓度氨氮环境,美人蕉和芦苇虽然受到低浓度氨氮的一些胁迫,但在高浓度时表现出色,美人蕉和芦苇对氨氮的耐受性更强。     

锌离子对菖蒲的胁迫反应研究

采用水培法,以Hoagland溶液为基础培养液,研究Zn2+胁迫对菖蒲幼苗生长状况、细胞渗透性、过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性、叶绿素以及脯氨酸质量比的影响。结果表明,Zn2+胁迫下菖蒲幼苗生长受到严重影响;随着Zn2+质量比的增加,叶片电导率不断增大;POD、SOD活性均高于对照,并且呈现先升高后降低的正相关趋势;叶绿素的质量比显著降低,与Zn2+质量比呈负相关趋势;脯氨酸质量比则一直呈上升的变化趋势。研究结果说明,酶活性的升高是由于菖蒲对Zn2+胁迫做出的应激反应,而高质量比Zn2+却对菖蒲的保护酶活性有抑制作用。     

生活污水对蚕豆根尖细胞致畸效应的研究

以蚕豆根尖为材料,采用蚕豆根尖细胞的微核试验和染色体畸变试验方法,研究不同取样点生活污水对蚕豆根尖细胞的致畸效应.结果表明:生活污水能诱发微核率升高,而且在一定范围内,其微核率随污染物浓度升高而增加,但高于一定浓度后有下降趋势;不同取样点的污水均使蚕豆根尖细胞有丝分裂指数下降;生活污水还能诱导蚕豆根尖细胞产生较高频率的染色体畸变.所以生活污水蚕豆根尖细胞具有明显的致畸效应.     

醋柳红素胶囊对老龄小鼠的抗氧化作用

本文研究醋柳红素胶囊对老龄小鼠的抗氧化作用。给予老龄小鼠不同剂量的醋柳红素胶囊内容物灌胃,连续30d,检测小鼠血清中超氧化物歧化酶(SOD)活性,全血谷胱甘肽过氧化物酶(GSH-PX)活性和过氧化脂质(MDA)的含量。结果表明醋柳红素胶囊无提高小鼠红细胞SOD活性,能提高GSH-PX活性,显著降低小鼠血中MDA含量,结果显示醋柳红素胶囊具有抗氧化作用。     

锌胁迫对长药景天生理特性的影响

[目的]利用低浓度和高浓度的Zn SO4溶液对长药景天的长期胁迫,研究长药景天锌胁迫下的抗性能力。[方法]采用盆栽试验,锌以Zn SO4·7H2O的形式供给,浓度分别为0、160和1 600 mg·kg-1Zn SO4,分别于0、7、14、21、28、35 d采集长势健康,且个体相近的植株,在相同部位选取功能叶片,测定长药景天叶片生理指标的变化。[结果]表明:低浓度(160 mg·kg-1Zn SO4)锌胁迫下,长药景天叶片电导率和MDA含量增加不显著;SOD、POD和CAT等保护酶活性增加,脯氨酸、可溶性糖和可溶性蛋白含量增加,高浓度(1 600 mg·kg-1Zn SO4)下电导率和MDA含量增加,保护酶活性增加,脯氨酸、可溶性糖和可溶性蛋白含量变化较小。[结论]长药景天对锌胁迫表现出较强的抗性,低浓度锌胁迫下调节能力较强,高浓度下主要依赖于保护酶系统的调节作用抵抗锌胁迫。在持续锌胁迫过程中,长药景天生理上能迅速作出相应的适应性调节,对锌胁迫表现出一定的忍耐能力和较强的恢复能力。     

高含铁红壤土重金属铜对水稻生长的影响

为了阐明高含铁红壤土背景下重金属Cu对水稻生长与生理特性的影响,结合盆栽模拟方法,采取正交试验组合,分析不同浓度高含铁红壤耕作土中重金属Cu胁迫下水稻分蘖期生长、生理特性的影响。数据表明:无外源铜背景下高含铁红壤耕作土(外源铁Fe≤400 mg/kg)有利于水稻的生长与发育,无外源铁背景下低浓度Cu(≤100 mg/kg)以及低浓度Cu(≤100 mg/kg)、Fe(≤200 mg/kg)组合均对作物的生长起到促进的作用,可以促进水稻株高、分蘖数、叶面积和叶绿素含量的增加,诱导水稻叶片SOD、POD与CAT活性。然而,当外源Fe浓度超过800mg/kg或者Cu浓度超过200 mg/kg时,尽管抗氧化酶SOD、POD与CAT活性受到极显著诱导,但水稻的生长开始明显受到影响;与自然背景下对照组相比较,水稻生长与生理特性出现显著差异,在最大受试浓度组水稻叶片已经开始枯萎。结果表明,低浓度Fe与Cu可以促进作物的生长,高浓度Fe与Cu则抑制作物的发育;高含铁土壤中,Fe元素与Cu元素对水稻的生长或抑制会产生协同作用。IBR综合分析表明,相较与外源铁胁迫,外源铜胁迫对水稻生物标志物综合效应影响更大。     

“沙棘花青素软胶囊”抗氧化实验研究

按保健食品抗氧化功能检验方法,采用SPF级昆明种老龄小鼠作为实验动物,开展"沙棘花青素软胶囊"抗氧化功能酶活力测定,并按保健食品抗氧化功能指标判定其抗氧化作用。试验结果表明:沙棘原花青素受试样品组与老龄对照组及溶剂对照组比较,过氧化脂质(MDA)含量降低及抗氧化功能酶(SOD)活力升高均有统计学意义,判定"沙棘花青素软胶囊"抗氧化功能试验结果为阳性。     

自然河道中沉水植物苦草对水流的生理响应

通过野外现场研究苦草生长和生理对水流的响应规律。结果表明:30~40 cm/s的水流速度对苦草的生长形态有影响;与静水区相比,动水区中苦草植株矮小、叶片较窄。在植物生长旺季和生殖生长期间,动水对植物细胞内的蛋白质和可溶性糖含量有促进作用,同时也诱导过氧化氢(H2O2)等活性氧上升,使得超氧化物歧化酶(SOD)、过氧化氢酶(CAT)等抗氧化酶活性相应提高以降低活性氧伤害;30~40 cm/s的流速对苦草生长有一定的影响,但不影响苦草在河道生态修复中的应用。     

以TEOS为硅源的聚硅氯化铝的絮凝性能及残留铝研究

用正硅酸乙酯(TEOS)与AlCl3溶液合成硅铝分布均匀的新型聚硅氯化铝[PASC(A)]混凝剂,并对其进行除浊性能试验。研究了产品B值、Si/Al摩尔比和絮凝体系pH对除浊性能及其在水中残留铝的影响,还与传统方法合成的PASC(B)做了比较。结果表明,PASC(A)具有优良的除浊效果和较低的残留铝含量,且受pH影响较小;具有较低的荷正电性和较宽的最佳投药范围;PASC(A)B 值和Si/Al摩尔比的增大,有助于提高除浊效果和降低残留铝含量。     

覆膜对油菜修复铅污染土壤影响研究

通过不同铅含量土壤上的覆膜油菜微区试验,分析了覆膜对油菜修复铅污染土壤的影响。结果表明：覆膜条件下油菜叶片和根部的铅含量随着生长期的延长而增加。在同一生长时期,油菜叶片和根部的铅含量随着土壤铅添加量的增大而增加。覆膜条件下不同铅浓度处理土壤油菜叶片和根部的铅含量均大于不覆膜处理,且施铅浓度越大,影响越明显;油菜叶片和根部铅含量越大,油菜鲜重越小。     

硫化物胁迫对马来眼子菜生理生化指标的影响

为研究水体中硫化物(S2-)对马来眼子菜的胁迫作用,通过静态模拟试验,分析了不同S2-水平(0、0.05、0.10、.2和0.3 mmol/L)培养下马来眼子菜叶绿素总量、丙二醛和2种抗氧化酶(过氧化氢酶、过氧化物酶)的活性变化。研究发现,当试验水体中c(S2-)≤0.05mmol/L时,马来眼子菜叶绿素总量随培养时间呈增加趋势,当c(S2-)0.2 mmol/L时,植物生长会受到明显影响,叶绿素浓度下降,光合作用受到抑制;不同S2-浓度组中马来眼子菜丙二醛浓度在暴露时均显示应激效应,膜质过氧化程度随水体S2-浓度及其暴露时间的增加而加重;在c(S2-)≤0.05 mmol/L时,2种抗氧化酶的活性得以维持或提高,当c(S2-)≥0.1 mmol/L时,马来眼子菜体内抗氧化酶活性下降,抗逆性降低,表现为剂量-负效应关系。     

Toxicity of perfluorononanoic acid and perfluorooctane sulfonate to Daphnia magna

In order to study toxicological effects of perfluorononanoic acid(PFNA), perfluorooctane sulfonate(PFOS), and their mixtures(PFNA/PFOS) on Daphnia magna(D. magna), a suite of comprehensive toxicity tests were conducted, including a 48-h acute toxicity test, a 21-day chronic test, a feeding experiment, and a biomarker assay. D. magna were exposed to aqueous solutions of PFNA and PFOS(alone and in combination) at concentrations ranging from 0.008 to 5 mg/L. The survival, growth, and reproduction of D. magna were monitored over a 21-day life cycle. The biomarkers, including acetylcholinesterase(ACh E), superoxide dismutase(SOD), and catalase(CAT) activities, were determined after seven days of exposure. PFOS was more toxic than PFNA based on the results of the acute toxicity test. Perfluorinated compounds(PFCs) inhibited both growth and reproduction of D. magna during the testing period. The ingestion rates and the biomarkers,including ACh E, SOD, and CAT activities, were significantly inhibited by PFCs in most cases. Moreover, the combined effects related to the growth and reproduction showed the antagonistic effects of PFCs.     

Biochemical responses of freshwater fish Carassius auratus to polycyclic aromatic hydrocarbons and pesticides

The freshwater fish Carassius auratus was chosen as an experimental subject, and their hepatic biochemical responses to the medium-term exposure of Benzo(k)fluoranthene (BkF) alone and in combination with PCB118 and dichlorodiphenyltrichloroethane (DDT) were investigated by measuring the reduced glutathione (GSH), glutathione S-transferase (GST), and thiobarbituric acid reactive substances (TBARS), to assess sublethal effects. The hepatic GSH content was significantly inhibited by organic pollutants, alone and in mixtures, while the TBARS content was significantly induced after three days of exposure. Bell-shaped concentration-response charts of GST activities were obtained. Significant dose-response relationships were found for hepatic GSH and TBARS contents of all concentrations and for the GST activity, except at the highest concentration. The GSH content, GST activity, and TBARS content in Carassius auratus were confirmed as useful biomarkers of exposure to organic pollutions.     

Distribution of Heavy Metal and Organic Contaminants in Plants and Soils of Windsor and Essex County,Ontario

Concentrations of four contaminants were determined in the soils and plants of Essex County and the city of Windsor in southwestern Ontario. Concentrations of lead and cadmium in county soils were not significantly greater than accepted provincial background levels; average concentrations were 12 mg kg^–1 and 0.38 mg kg^–1 dry soil for lead and cadmium, respectively. Lead concentration in tissues of crop plants was less than 1/4 of that in adjacent soil; cadmium concentration was similar to that in adjacent soil. Concentrations of both metals were significantly higher within the city. Soil lead averaged 44.8 mg kg^–1 and soil cadmium 0.62 mg kg^–1 dry soil. These concentrations correlated significantly with traffic volume on nearby streets. In roots of Chenopodium averages were 18.1 mg kg^–1 for lead and 0.60 mg kg^–1 for cadmium. PCBs were generally undetectable or present only in trace amounts in both soils and goldenrod plants in Essex County. Octachlorostyrene (OCS), while undetectable in soil, was found in leaves at concentrations of about 1 μg kg^–1 in the county. City soils contained higher concentrations of PCBs; average Arochlor 1260 concentration was 13.17 μg kg^–1; OCS was not detectable. Concentrations of both OCS and Arochlors 1254 and 1260 were higher in goldenrod tissues in the city than in parallel county samples. These data suggest limited dispersal of pollutants from urban-industrial sources into the surrounding area.     

水解酸化-好氧移动床膜生物反应器处理高浓度有机废水的试验研究

好氧移动床膜生物反应器(M-CMCBR)是生物膜法与微滤膜相结合的一种新型反应器。采用水解酸化-好氧移动床膜生物反应器处理高浓度有机废水和含酚废水。试验结果表明:此工艺可以提高难降解有机废水的可生化性,继而得到较好的出水水质。进水CODCr为3000～5000mg/L时,最终膜出水CODCr为30～90mg/L,总去除率为98.5%～99.5%。     

漳泽水库富营养化调查与评价

通过对漳泽水库水质营养源分析，说明造成水质富营养化的外源污染物主要为CODcr、NH3-N，内源污染主要为网箱养鱼源。浮游植物调查和蚕豆根尖细胞微核试验结果与主要水化学指标评价较为一致。针对调查结果，结合实际提出了水库富营养化的防治措施。     

Effect of Milfoil (Myriophyllum Spicatum L.) on Phosphorus Movement Between Sediment and Water

Milfoil (Myriophyllum spicatum L.), grown in 10-liter battery jars and rooted in pond sediment, showed no leakage of P from the shoots into the surrounding water, even when P concentration in the water was 5 μg/L but 1000 μg/L in sediment water around the roots. P added to the water dropped to concentrations of about 10 μg/L in both planted and sediment only jars, but fell somewhat faster when milfoil was growing in the jars. This particular type of milfoil in its rapidly growing stage absorbed P through its leaves and stems and did not show any signs of acting as a conduit for increased movement of soluble P from enriched sediment water to overlying water, compared to sediment-water jars with no plants. When dissolved P levels were maintained at low levels (10 μg/L in the water), root absorption could not supply enough P to maintain plant tissues at their initial P content of about 0.80 percent, dry wt. No changes in sediment P over the course of the experiment could be assigned to the plants’ presence.     

藻华聚积及污水入流对太湖上下层水体营养盐含量的影响

通过采集太湖水体鲜藻和入湖区混合常见污水,应用再悬浮发生装置,室内模拟有底泥参与的不同藻类聚积和不同CODCr含量污水进入条件下,太湖西北竺山湖区水质上下层水体中SS,NH3-N及PO43-质量浓度的变化过程。分析结果表明:在7 d的常见风浪模拟环境中,无论加入藻类还是加入污水,太湖上下层水体中SS质量浓度均呈下降趋势,表明颗粒物有向水底沉降的可能;水体中的NH3-N和PO43-质量浓度并未因藻量增加而上升,反映出鲜藻此时对水体中的N和P呈吸收作用;污水添加量的增大则使试验水柱中NH3-N和PO43-质量浓度上升,并大致随时间的增加呈逐步上升的趋势。