Water Quality of Aroeira River for Use in Irrigation of Vegetable Crops in the Northern Region of the State of Espirito Santo,Brazil

The aim of this study was to evaluate the physical, chemical and microbiological quality of the water of the Aroeira River in the city of Silo Mateus, northern region of Espirito Santo State, Brazil, from April 2012 to March 2013, for use in irrigation of vegetable crops. Five points were selected along the river for analysis of pH, chloride （mg/L C1-）, total hardness （mg/L CaCO3）, dissolved oxygen （mg/L O2）, ammoniacal nitrogen （mg/L N-NH3）, total iron （mg/L Fe）, phosphate/orthophosphate （mg/L PO43-）, turbidity （NTU）, acidity （mg/L CO2）, temperature （℃）, electrical conductivity （dS/m）, as well as microbiological and parasitological analyses. Only point l, located upstream of the points of domestic sewage discharges, is the closest to be considered suitable for use in irrigation of vegetable crop, demonstrating the possible risks to the health of populations who use water with sewage discharges in urban communities for irrigation of vegetable crops.     

番茄温敏核不育系花药培养诱导愈伤组织的研究

[目的]探讨影响番茄温敏核不育系花药培养诱导愈伤组织的相关因子。[方法]研究不同灭菌处理、不同基本培养基、不同激素种类及浓度对番茄温敏核不育系花药培养诱导愈伤组织的影响。[结果]0．1％HgCl28min＋10％NaClO8min的灭菌处理效果最佳,菌污染率仅为1．95％,出愈率达71．73％;在MS、B5Miller3种基本培养基的比较试验中,以MS为基本培养基对花药愈伤组织的诱导效果最好;诱导愈伤组织的适宜浓度为2,4-D1mg／L、6-BA2mg／L、KT2mg／L。[结论]灭菌处理、基本培养基、激素种类及浓度可以影响番茄温敏核不育系花药培养诱导愈伤组织的效果。     

Deoxynivalenol in wheat milling fractions: A critical evaluation regarding ongoing and new legislation limits

New maximum limits (ML) for deoxynivalenol (DON) in wheat and its products were set in Brazil in 2017, and new changes are scheduled for 2019. The concentration of DON in wheat and milling fractions (bran, shorts, break flour, reduction flour) was evaluated in samples from commercial fields to discuss the effects of the new legislation. Cleaned wheat samples contaminated with DON had concentrations ranging from 308 to 2373 ng g⁻¹ (n = 29), and one sample had a concentration of 3426 ng g⁻¹. DON concentration obtained in bran and shorts were significantly higher than that of the flours. Compared to the initial concentration in cleaned wheat, DON relative concentrations were 73 and 35% higher in bran and shorts, respectively, and 67% lower in the straight run flour (break plus reduction flour). The bran and straight run flour contained DON concentrations that were 62.1 and 17.2% respectively higher than that of the ML set in Brazil in 2017; additionally, these values would reach 65.5 and 34.5%, respectively, according to the changes to be in effect in 2019. The present study demonstrates DON distribution in wheat milling fractions, thus, providing updated information for the management of DON contamination for the industry and policymakers.     

Mine waste contamination limits soil respiration rates: a case study using quantile regression

We present an application of a statistical approach, quantile regression (QR), which identifies trends in soil processes otherwise masked by spatial and temporal variability. QR identifies limits on processes and changes in the variance of a response along an environmental gradient. We quantified in situ soil respiration, pH, and heavy metal concentrations across a mine waste contamination gradient that spanned greater than an order of magnitude of metal concentrations. Respiration values were monitored at study sites over 2 years. We used QR to show that soil respiration was limited with respect to both heavy metals and pH, and that both increased metals and increased acidity constrained variation in soil respiration values. Maximum respiration values declined by 48% over the Metals Contamination Index (MCI) range and by 72% over the pH range. The use of QR avoided the necessity of discriminating between multiple sources of variation in a spatially and temporally variable system. It is often unrealistic or too time consuming and expensive to attempt to measure all of the relevant predictor variables in the field. The simpler approach offered by QR is to explore factors that limit a process, recognizing that not all of the factors contributing to a soil function will be measured. An application of this approach to the evaluation of a mine waste remediation procedure is discussed.     

干旱区绿洲受污染土壤中Cd和Pb在油菜中的累积与迁移

运用Tessier五步连续提取法研究干旱区绿洲受污染土壤中重金属Cd、Pb在油菜中的积累与迁移。结果表明,①原状土中Cd主要以碳酸盐结合态为主,Pb主要以残留态为主,随着外源性Cd投加量的增加,交换态、碳酸盐结合态、铁锰氧化物结合态含量增大,有机结合态、残留态含量随投加量的增加有所减少,且残留态呈锐减趋势,各形态Pb含量均随投加量的增加而升高,碳酸盐结合态、铁锰氧化物结合态Pb的含量增幅较大。②随着外源性Cd、Pb投加量的增加,油菜根和叶中累积的Cd、Pb含量随之增加。用土壤中各形态Cd、Pb的含量与油菜叶和根部累积的Cd、Pb含量做逐步回归分析,发现土壤中的碳酸盐结合态Cd、Pb与油菜叶和根部累积的Cd、Pb含量呈极显著相关。表明碳酸盐结合态对油菜各器官Cd、Pb的累积有最大贡献。③油菜叶和根部Cd的富集系数均大于1,Pb的富集系数均小于1。Cd的富集系数大于Pb,表明油菜吸收Cd的能力大于Pb,其毒害作用也相应大于Pb;Cd的富集系数叶部均大于根部,表明Cd在油菜中的迁移性较强;Pb叶部的富集系数小于根部,表明Pb主要在油菜根部累积,迁移性较差。     

工厂化生产组培苗的污染及其控制研究

每月对组培环境空气中污染菌、组培苗污染监测表明:组培苗污染程度与组培环境空气中的真菌数量均随时间呈同步变化;组培环境空气中真菌主要有12种,其中,优势菌为芽枝霉、灰霉、木霉、曲霉、青霉等5种。甲醛熏蒸可使组培环境空气中的真菌减少87%～100%。     

酒精消毒液污染解淀粉芽孢杆菌的临床生物学调查

目的:在医院感染监测中发现75%酒精消毒液被解淀粉芽胞杆菌污染,检测与分析解淀粉芽孢杆菌的生物学特性,为防止临床常用75%酒精消毒剂的污染及医院感染而提供消毒灭菌方法与实验依据。方法:按照《消毒技术规范》标准进行细菌总数检测;用VITEK-32型全自动细菌鉴定仪检测细菌;常规方法检测该细菌对理化因素的抵抗力;K-B法进行药物敏感性试验。结果:追踪到医院制剂室75%乙醇消毒剂中培养出同一种细菌,细菌总数>800 cfu/mL,鉴定为解淀粉芽孢杆菌。该细菌耐煮沸5 min,在95%乙醇中生长良好,对1∶50的84消毒液和臭氧等均不敏感;而紫外线照射30 min、250 mg/L健之素作用5 min及高压灭菌等对其有较好的杀灭作用;对常用的13种抗生素敏感,7种抗生素耐药。结论:75%乙醇消毒液容易受到解淀粉芽胞杆菌的污染,配制时应对容器及空气环境进行严格地消毒灭菌,杀灭细菌芽胞应选用适宜的消毒灭菌方法。     

南淝河水及沉积物中的重金属污染评价

分析,评价了南淝河水及其沉积物中的重金属含量状况。结果表明,南淝河河水重金属含量较低,属国家地面Ⅱ类标准,但沉积物中的重金属污染严重,是河流背景值的几倍甚至几十倍。南淝河下游两岸合肥市工业区是污染产生的主要污染源。     

绥满公路沿线不同植被区土壤表层重金属污染状况

以绥满公路(G015)黑龙江境内黄牛场至胜利段为研究区,根据路段所处位置、土壤类型、交通量将其分为南段、中段和北段,分别对3段公路沿线,距公路不同距离的96个样点的土壤表层的6种重金属质量分数进行分析。结果表明,3段公路沿线土壤表层5种重金属质量分数平均值均高于背景值。根据单因子污染指数分级标准,Cd在南段和中段为重污染;北段为中度污染;Zn、Cu、Pb和Ni在三段中均为轻污染。据潜在生态危害单项指数分析,Cd为强生态危害,其余均为轻微生态危害。潜在生态危害综合指数由大到小的排序为:南段、中段、北段,均为轻微生态危害。相关性分析及结果显示公路建设及运营是造成土壤中Pb、Cd、Zn、Cu污染的主要原因。在空间分布上,重金属质量分数由大到小的排序为南段、中段、北段。横向空间分布显示,公路沿线重金属与公路距离之间存在显著相关性,影响带宽度基本为0～200 m,峰值基本在50 m以内,超过50 m,影响效果明显减弱。     

番茄酱工业水污染物产排放量核算方法研究

从我国番茄酱产业发展现状入手,分析了番茄酱生产的原料消耗与生产工艺,综合考虑废水产生量、污染物浓度等方面的因素给出了番茄酱生产污染物排放量的计算公式。