Cadmium tolerance in six poplar species

Selection of poplar species with greater Cd tolerance and exploiting the physiological mechanisms involved in Cd tolerance are crucial for application of these species to phyto-remediation. The aim of this study is to investigate variation in Cd tolerance among the six poplar species and its underlying physiological mechanisms. Cuttings of six Populus species were cultivated for 10 weeks before exposure to either 0 or 200 μM CdSO₄ for 20 days. Gas exchange in mature leaves was determined by a portable photosynthesis system. Cd concentrations in tissues were analyzed by a flame atomic absorbance spectrometry. Subsequently, Cd amount per plant, bio-concentration factor (BCF) and translocation factor (T _f) were calculated. Nonenzymatic compounds and activities of antioxidative enzymes in tissues were analyzed spectrophotometrically. Cd exposure caused decline in photosynthesis in four poplar species including Populus cathayana (zhonghua 1). Among the six species, P. cathayana (zhonghua 1) displayed the highest Cd concentrations in tissues, the largest Cd amount in aerial parts, the highest BCF in aerial parts and T _f under Cd exposure. Under Cd stress, increases in total soluble sugars in roots but decreases in starch in roots, wood, and leaves of P. cathayana (zhonghua 1) were found. Induced O ₂ ^?? and H₂O₂ production in roots and leaves, and increases in free proline, soluble phenolics, and activities of antioxidative enzymes were observed in P. cathayana (zhonghua 1). Based on results of this pot experiment, it is concluded that P. cathayana (zhonghua 1) is superior to other five species for Cd phyto-remediation, and its well-coordinated physiological changes under Cd exposure confer the great Cd tolerance of this species.     

Degradation of bisphenol A in aqueous solution by persulfate activated with ferrous ion

Degradation of bisphenol A (BPA) in aqueous solution was studied with high-efficiency sulfate radical (SO₄ ^?·), which was generated by the activation of persulfate (S₂O₈ ^2?) with ferrous ion (Fe²⁺). S₂O₈ ^2? was activated by Fe²⁺ to produce SO₄ ^?·, and iron powder (Fe⁰) was used as a slow-releasing source of dissolved Fe²⁺. The major oxidation products of BPA were determined by liquid chromatography-mass spectrometer. The mineralization efficiency of BPA was monitored by total organic carbon (TOC) analyzer. BPA removal efficiency was improved by the increase of initial S₂O₈ ^2? or Fe²⁺ concentrations and then decreased with excess Fe²⁺ concentration. The adding mode of Fe²⁺ had significant impact on BPA degradation and mineralization. BPA removal rates increased from 49 to 97 % with sequential addition of Fe²⁺, while complete degradation was observed with continuous diffusion of Fe²⁺, and the latter achieved higher TOC removal rate. When Fe⁰ was employed as a slow-releasing source of dissolved Fe²⁺, 100 % of BPA degradation efficiency was achieved, and the highest removal rate of TOC (85 %) was obtained within 2 h. In the Fe⁰–S₂O₈ ^2? system, Fe⁰ as the activator of S₂O₈ ^2? could offer sustainable oxidation for BPA, and higher TOC removal rate was achieved. It was proved that Fe⁰–S₂O₈ ^2? system has perspective for future works.     

Biotreatment of chromite ore processing residue by Pannonibacter phragmitetus BB

Chromite ore processing residues (COPR) is the source of the Cr(VI) contamination in the environment. Pannonibacter phragmitetus BB was used to treat two different types of COPRs in this research. The water-soluble Cr(VI) of COPR A and B is 3,982.9 and 1,181.4 mg/kg, respectively. In the column biotreatment process, P. phragmitetus BB can reduce Cr(VI) in the leachate to an undetectable level at the flow rate of 1 and 2 ml/min. In the direct biotreatment process, Cr(VI) in the liquid supernatant of COPR A and B decreased from 265 and 200 mg/l to 145 and 40 mg/kg after 240 h of incubation. In one-step and two-step biotreatment processes, Cr(VI) in the liquid supernatant of both COPRs can be reduced to an undetectable level. The toxicity characteristic leaching procedure results indicate that the Cr(VI) concentration of treated COPR A (3.48 mg/l) is lower than the identification standards for hazardous wastes of China (5 mg/l) (GB 5085.6-2007). The information obtained in this study has significance for the application of P. phragmitetus BB to remediate COPR contamination.     

Distribution and temporal trend of polybrominated diphenyl ethers in one Shanghai municipal landfill, China

The scarcity of information on polybrominated diphenyl ethers’ (PBDEs) flow in landfill restricts the life cycle analysis of PBDEs. In this study, eight PBDE congeners (BDEs 28, 47, 99, 100, 153, 154, 183, and 209) in topsoil, vegetation leaves, leachate, and municipal aged refuse collected from Shanghai Laogang Municipal Landfill (SLML) were investigated. The present study revealed elevated PBDE concentrations in topsoil and proved PBDE leakage from SLML and vegetation uptake. BDE-209 was the predominant congener, and this could be due to massive usage of deca-BDE mixture in Shanghai. ΣPBDE concentrations in leachates treated by reed wetland and A²/O process fell in the low end of the worldwide range. ΣPBDE concentrations in aged refuse samples rose from under 50 ng/g dw in 1989 to the range of 5,150–5,718 ng/g dw in 2002. PBDE concentrations increase in aged refuse samples throughout the 1990s into the 2000s paralleled municipal solid waste output from 1991 to 2002 in Shanghai. Exponential increase in BDE-209 concentration in aged refuse suggested the increasing market demands for deca-BDE mixture after 1990 in China. Notably, the inventory of PBDEs in SLML was 28.7 MT, and the doubling time of BDE-209 in aged refuse was calculated to be 1.6 year. SLML can be considered as a source of PBDE and one main recipient of PBDE as well, receiving inputs predominantly from the PBDE-containing waste. Priority should be given to formulate regulation on PBDEs and sorting work before landfill disposal.     

江苏省地理标志概况与价值评估体系构建研究

以江苏省43个地理标志为研究对象,根据国家地理标志的分类方法对其进行分类,构建价值评估体系,探讨地理标志产品的内在价值及发展重点。研究表明,江苏省地理标志类型较为单一,分布均匀;开发程度不同,可分为开发匮乏型、有待开发型和开发成熟型。通过价值体系评价可见,江苏省应重点挖掘产品的自身特色,发展价值意义突出的地理标志。     

Assessing benzene-induced toxicity on wild type Euglena gracilis Z and its mutant strain SMZ

Benzene is a representative member of volatile organic compounds and has been widely used as an industrial solvent. Groundwater contamination of benzene may pose risks to human health and ecosystems. Detection of benzene in the groundwater using chemical analysis is expensive and time consuming. In addition, biological responses to environmental exposures are uninformative using such analysis. Therefore, the aim of this study was to employ a microorganism, Euglena gracilis (E. gracilis) as a putative model to monitor the contamination of benzene in groundwater. To this end, we examined the wild type of E. gracilis Z and its mutant form, SMZ in their growth rate, morphology, chlorophyll content, formation of reactive oxygen species (ROS) and DNA damage in response to benzene exposure. The results showed that benzene inhibited cell growth in a dose response manner up to 48 h of exposure. SMZ showed a greater sensitivity compared to Z in response to benzene exposure. The difference was more evident at lower concentrations of benzene (0.005–5 μM) where growth inhibition occurred in SMZ but not in Z cells. We found that benzene induced morphological changes, formation of lipofuscin, and decreased chlorophyll content in Z strain in a dose response manner. No significant differences were found between the two strains in ROS formation and DNA damage by benzene at concentrations affecting cell growth. Based on these results, we conclude that E. gracilis cells were sensitive to benzene-induced toxicities for certain endpoints such as cell growth rate, morphological change, depletion of chlorophyll. Therefore, it is a potentially suitable model for monitoring the contamination of benzene and its effects in the groundwater.     

离子交换法选择性回收污泥厌氧消化液中的磷

为探讨高效选择性回收污泥厌氧消化液中磷的离子交换方法,采用静态实验和动态实验研究了4种阴离子交换树脂（D213、D202、D301和DSQ）的磷回收性能,筛选了适合富磷污泥厌氧消化液选择性磷回收的高交换容量树脂。实验结果表明,D213、D202、D301和DSQ 4种树脂对正磷浓度为70 mg/L的厌氧消化液进行动态处理时,其最大穿透体积分别为3、7、17和90 BV;DSQ树脂磷交换容量远高于其他3种树脂,达到6 860 mg P/L湿树脂,是目前报道的高磷交换容量树脂的3~4倍;DSQ树脂能有效地抵抗厌氧消化液中有机质和硫酸根等阴离子的干扰;用NaOH溶液再生DSQ树脂并回收磷,磷洗脱率超过96%,洗脱液是高浓度含磷液,可作为磷矿石的优质替代品。研究表明,DSQ树脂是一种高效选择性分离磷的树脂,适用于污泥厌氧消化液的磷回收。     

钢渣掺量对泡沫混凝土砌块性能的影响

泡沫混凝土是一种环保、节能的保温隔热材料,以其优良的保温性能,受到越来越多研究者的关注。对钢渣的特性进行了分析测试,对钢渣不同掺量对泡沫混凝土砌块特性的影响进行了研究,结果表明,采用添加5％～35％钢渣所制备的钢渣泡沫混凝土砌块,其密度等级为JC／T1062—2007中的B10级,掺人5％、15％钢渣的泡沫混凝土抗压强度达到A3．5等级,掺人25％、35％钢渣的泡沫混凝土抗压强度达到A2．5等级。随着钢渣掺量的增大,抗压强度、抗折强度降低,吸水率增大。在同一钢渣掺量的情况下,泡沫混凝土砌块的抗压强度变化率增加显著,而且随着钢渣的加入量升高而增大。钢渣的加入有利于提高泡沫混凝土砌块的后期抗压强度。     

长江干流江苏段水质评价

利用长江干流江苏段16个断面的水质监测资料,采用最差因子评价法,对长江干流江苏段的16个断面水质状况进行了分析评价。结果表明,长江干流江苏段的水质以Ⅱ、Ⅲ类为主,夏半年的水质优于冬半年,部分断面水质较差,各断面的主要污染物以氨氮为主。     

四川省空气自动监测数据采集系统建设

介绍了四川省空气质量监测工作的现状和存在的问题,提出了建设四川省空气自动监测数据采集系统的技术路线,建设完成了全省空气监测数据的统一采集。