蚕豆对铯的吸收蓄积及亚细胞分布研究

采用改良水培法培养蚕豆幼苗至2片真叶,置于含铯(ρ(Cs+)8.24(CK)~200 mg·L~(-1))的营养液中处理7 d、14 d、21 d后取样。采用差速离心法分离亚细胞组分,采用原子吸收分光光度法测定根、茎、叶及各亚细胞组分的Cs+含量,分析蚕豆幼苗对Cs+的吸收蓄积及亚细胞分布特点,研究蚕豆对Cs+的富集转运特征及耐受机理。结果显示:蚕豆3种器官对Cs+的蓄积量为根叶茎,根对Cs+的蓄积量占总量的65.13%~83.17%,最高(ρ(Cs+)200 mg·L~(-1)时)达到518.40 mg·kg~(-1)FW(7 d)、1 949.74 mg·kg~(-1)FW(14 d)和3 614.03 mg·kg~(-1)FW(21 d);蚕豆根、茎、叶中Cs+的亚细胞分布主要集中在细胞壁和可溶性组分中,Cs+相对含量分别达到75.84%~99.06%(根)、79.06%~100%(茎)、82.95%~100%(叶);细胞核、前质体、叶绿体和线粒体等细胞器仅含少量的Cs+(25%)。结果表明,蚕豆根、茎、叶细胞主要通过阻滞作用,将Cs+结合固定在细胞壁,并将进入细胞质基质的一部分Cs+转运到液泡内,暂时或"永久性"存贮,有效降低了细胞器、胞质溶胶(cytosol)及内含物中的Cs+含量,极大地减缓了Cs+对细胞器的功能性损伤,这是短期内蚕豆未表现出明显中毒症状的原因,也是蚕豆耐受Cs+胁迫的重要机理之一。     

深圳湾红树林湿地面源污染初期效应研究

研究了深圳湾红树林湿地雨水面源污染统计特征、污染过程线等方面内容,采用M(V)曲线法分析讨论了排入湿地的小沙河排放口污染物的特征规律。监测结果显示,BOD5、COD超过地表水环境Ⅴ类水指标,TN、TP没有超过地表水环境Ⅴ类水指标,表明现阶段流域附近的地区内的截污及河道清淤控制较好。M(V)曲线法分析表明,检测的各项污染物指标不存在明显的初期效应,其中BOD、COD、SS较TN、TP相对初期冲击强度较大。研究结果能够为红树林湿地水环境保护提供参考策略。     

Washing treatment of automotive shredder residue (ASR)

Worldwide, the amount of end-of-life vehicles (ELVs) reaches 50 million units per year. Once the ELV has been processed, it may then be shredded and sorted to recover valuable metals that are recycled in iron and steelmaking processes. The residual fraction, called automotive shredder residue (ASR), represents 25% of the ELV and is usually landfilled. In order to deal with the leachable fraction of ASR that poses a potential threat to the environment, a washing treatment before landfilling was applied. To assess the potential for full-scale application of washing treatment, tests were carried out in different conditions (L/S = 3 and 5 L/kg_TS; t = 3 and 6 h). Moreover, to understand whether the grain size of waste could affect the washing efficiency, the treatment was applied to ground (<4 mm) and not-ground samples. The findings obtained revealed that, on average, washing treatment achieved removal rates of more than 60% for dissolved organic carbon (DOC), chemical oxygen demand (COD) and total Kjeldahl nitrogen (TKN). With regard to metals and chlorides, sulphates and fluoride leachable fraction, a removal efficiency of approximately 60% was obtained, as confirmed also by EC values. The comparison between the results for ground and not-ground samples did not highlight significant differences.     

Circular economy practices among Chinese manufacturers varying in environmental-oriented supply chain cooperation and the performance implications

The rapidly growing industrial activities in emerging economies such as China have been causing resource depletion and pollution problems. This reality requires China to adopt an integrated management approach to resolve the conflict between industrial development and environmental protection, and the concept of circular economy (CE) serves this purpose. In this paper, we examine if different types of manufacturing enterprises on environmental-oriented supply chain cooperation (ESCC) exist. We also determine if the Chinese manufacturer types varying in ESCC differ in their implementation of the CE practices towards achieving the CE-targeted goals on improving both environmental and economic performance. Our cluster analytic results with multivariate analysis of variance (MANOVA) among the four identified types of Chinese manufacturers varying in environmental-oriented supply chain cooperation highlight the importance to intensify the cooperation with upstream and downstream supply chain partners for a CE initiative to succeed.     

Flood management: prediction of microbial contamination in large-scale floods in urban environments

With a changing climate and increased urbanisation, the occurrence and the impact of flooding is expected to increase significantly. Floods can bring pathogens into homes and cause lingering damp and microbial growth in buildings, with the level of growth and persistence dependent on the volume and chemical and biological content of the flood water, the properties of the contaminating microbes, and the surrounding environmental conditions, including the restoration time and methods, the heat and moisture transport properties of the envelope design, and the ability of the construction material to sustain the microbial growth. The public health risk will depend on the interaction of these complex processes and the vulnerability and susceptibility of occupants in the affected areas. After the 2007 floods in the UK, the Pitt review noted that there is lack of relevant scientific evidence and consistency with regard to the management and treatment of flooded homes, which not only put the local population at risk but also caused unnecessary delays in the restoration effort. Understanding the drying behaviour of flooded buildings in the UK building stock under different scenarios, and the ability of microbial contaminants to grow, persist, and produce toxins within these buildings can help inform recovery efforts. To contribute to future flood management, this paper proposes the use of building simulations and biological models to predict the risk of microbial contamination in typical UK buildings. We review the state of the art with regard to biological contamination following flooding, relevant building simulation, simulation-linked microbial modelling, and current practical considerations in flood remediation. Using the city of London as an example, a methodology is proposed that uses GIS as a platform to integrate drying models and microbial risk models with the local building stock and flood models. The integrated tool will help local governments, health authorities, insurance companies and residents to better understand, prepare for and manage a large-scale flood in urban environments.     

Mycelial growth and solid-state fermentation of lignocellulosic waste by white-rot fungus Phanerochaete chrysosporium under lead stress

Lignocellulosic biomass is an abundant renewable resource difficult to degrade. Its bioconversion plays important roles in carbon cycles in nature, which may be influenced by heavy metals in environment. Mycelial growth and the degradation of lignocellulosic waste by lignin-degrading fungus Phanerochaete chrysosporium under lead stress were studied. It was shown that P. chrysosporium could grow in liquid media with 400 mg L?1 Pb(II), and mycelial dry weight was reduced by 54% compared to the control. Yellow mycelia in irregular short-strip shape formed in Pb-containing media, whereas the control showed ivory-white regular mycelial pellets. Two possible responses to Pb stress were: dense hyphae, and secretion from mycelia to resist Pb. During solid-state fermentation of straw, fungal colonization capability under Pb stress was positively correlated with the removal efficiency of soluble-exchangeable Pb when its content was higher than 8.2 mg kg?1 dry mass. Carboxymethyl cellulase activity and cellulose degradation were inhibited at different Pb concentrations, whereas low Pb concentrations increased xylanase and ligninolytic enzyme activities and the hemicellulose and lignin degradation. Cluster analyses indicated that Pb had similar effects on the different microbial indexes related to lignin and hemicellulose degradation. The present findings will advance the understandings of lignocellulose degradation by fungi under Pb pollution, which could provide useful references for developing metal-polluted waste biotreatment technology.     

Application of integrated GIS and multimedia modeling on NPS pollution evaluation

In Taiwan, nonpoint source (NPS) pollution is one of the major causes of the impairment of surface waters. I-Liao Creek, located in southern Taiwan, flows approximately 90 km and drains toward the Kaoping River. Field investigation results indicate that NPS pollution from agricultural activities is one of the main water pollution sources in the I-Liao Creek Basin. Assessing the potential of NPS pollution to assist in the planning of best management practice (BMP) is significant for improving pollution prevention and control in the I-Liao Creek Basin. In this study, land use identification in the I-Liao Creek Basin was performed by properly integrating the skills of geographic information system (GIS) and global positioning system (GPS). In this analysis, 35 types of land use patterns in the watershed area of the basin are classified with the aid of Erdas Imagine process system and ArcView GIS system. Results indicate that betel palm farms, orchard farms, and tea gardens dominate the farmland areas in the basin, and are scattered around on both sides of the river corridor. An integrated watershed management model (IWMM) was applied for simulating the water quality and evaluating NPS pollutant loads to the I-Liao Creek. The model was calibrated and verified with collected water quality and soil data, and was used to investigate potential NPS pollution management plans. Simulated results indicate that NPS pollution has significant contributions to the nutrient loads to the I-Liao Creek during the wet season. Results also reveal that NPS pollution plays an important role in the deterioration of downstream water quality and caused significant increase in nutrient loads into the basin's water bodies. Simulated results show that source control, land use management, and grassy buffer strip are applicable and feasible BMPs for NPS nutrient loads reduction. GIS system is an important method for land use identification and waste load estimation in the basin. Linking the information of land utilization with the NPS pollution simulation model may further provide essential information of potential NPS pollution for all subregions in the river basin. Results and experience obtained from this study will be helpful in designing the watershed management and NPS pollution control strategies for other similar river basins.     

Volatile hydrocarbon emissions from vehicles and vertical ventilations in the Hsuehshan traffic tunnel, Taiwan

The concentrations of 56 volatile organic hydrocarbons (VOCs) were measured simultaneously in the southbound bore, the northbound bore and the exhaust air shafts of the Hsuehshan tunnel near Yilan, Taiwan during 2007 and 2008. A total of 60 integrated air samples were collected using stainless steel canisters and analyzed using GC/FID and GC/MS. The highest temperature and lowest relative humidity were observed at the exit of the tunnel owing to the accumulation in the tunnel of waste heat that was exhausted from vehicles. The five most abundant species in all samples were ethylene, acetylene, isopentane, propylene, and toluene. The exit/entrance ratios of total non-methane hydrocarbon (NMHC) concentration were 7.8 and 4.8 for the southbound and northbound bores, respectively. Furthermore, the most abundant species of emission rate (ER) is toluene (21.93-42.89 mg s(-1)), followed by isopentane, ethylene, propylene and 1-butene, with ER ranging from 2.50 to 9.31 mg s(-1) for the three shafts. The ozone formation potential (OFP)/total NMHC ratios in three exhaust air shafts show that the reactivities of these emissions are similar to those of vehicle emissions.     

The relationship between typhoons' peripheral circulation and ground-level ozone concentrations in central Taiwan

Surface data of meteorological parameters (wind speed, wind direction, and mixing height) and air pollutant concentrations (O₃, NO, and NO₂) were collected for a 92-day period associated with typhoon formation in 2005. The influence of typhoons on O₃ concentration were defined by azimuth and distance from Taiwan, and Types A, B, and C correspond to typhoons less than 1,500 km from Taiwan and located between azimuths 45° and 135°, 135° and 225°, and 225° and 45°, respectively. Type D corresponds to typhoons more than 1,500 km from Taiwan. Titration reactions were conducted at three temporal phases: 2000–0700, 0800–1100, and 1200–1400 LST (Local Standard Time). The air pollution model (TAPM) was used to simulate wind fields and trajectories of air masses. It was determined that typhoon position affected O₃ concentration, temporal and spatial patterns of O₃ titration and vertical meteorological characteristics, which were not all at the statistically significant level.