Response of extracellular and intracellular alkaline phosphatase in Microcystis aeruginosa to organic phosphorus

Environmental Science and Pollution Research - Cyanobacterial blooms caused by Microcystis have become a menace to public health and water quality in the global freshwater ecosystem. Alkaline...     

超声 — 溶菌酶协同处理强化纺织印染污泥脱水性能研究

污泥脱水是实现污泥减量和减容的关键处理工艺。以纺织印染污泥为研究对象,考察超声能量密度和超声时间对超声—溶菌酶协同处理纺织印染污泥脱水性能的影响。结果表明,适当的超声能量密度和超声时间能够对印染污泥脱水产生积极作用,且超声预处理的最佳工况为超声能量密度2.0W/mL、超声时间20min。在最佳工况下泥饼含水率为62.3%,污泥比阻(SRF)为(3.21±0.12)×10~(12)m/kg。溶胞效率表现为超声—溶菌酶协同处理超声处理溶菌酶水解。污泥经过超声—溶菌酶协同处理后,体积减小近50%,脱水性能明显改善。     

Toxicity assessment of municipal sewage treatment plant effluent by an integrated biomarker response in the liver of crucian carp (Carassius auratus)

In this study, crucian carp (Carassius auratus) was exposed to the increasing concentrations of municipal sewage treatment plant effluent (MSTPE) for 15 days, and the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and acetylcholinesterase (AChE), together with the contents of malondialdehyde (MDA) and glutathione (GSH) in the liver of C. auratus were investigated. Moreover, the integrated biomarker response (IBR) approach was applied to assess the adverse effects of MSTPE in freshwater. The aim of the study was to provide an effective biological indicator for evaluating the toxicity effects and ecological risks of MSTPE in the freshwater environment quantitatively. Results showed that MSTPE could cause oxidative damage to the liver of C. auratus, which reflected through the increasing MDA content over the exposure period. MSTPE also led to the biochemical responses of antioxidant defense in C. auratus liver, such as the enhancement of SOD, CAT, and GPx activities, as well as the inhibition of AChE activity and GSH content. It was found that MDA, SOD, GPx, and GSH could be used as the biomarkers for reflecting the adverse effects of MSTPE in the receiving freshwater on the 12th day of exposure. A significant increase of IBR values was observed as the increasing concentration of MSTPE, and the IBR values presented a significant positive correlation (r?=?0.891, P?<?0.05) with the increasing concentrations of MSTPE, indicating that IBR approach is a promising tool for assessing the toxicity effects of MSTPE in environmental freshwater.

     

Health risk assessment of groundwater nitrate contamination: a case study of a typical karst hydrogeological unit in East China

Environmental Science and Pollution Research - Nitrate pollution in rivers, lakes, shallow groundwater, and even deep groundwater occurs in many parts of the world. And, it’s essential to...     

基于风险修正的城市安全风险评估方法及应用*

为推动实现城市安全风险的系统化、信息化管理,基于我国城市安全风险管理的要求与特点,总结城市安全风险评估的分层分类原则、突出固有风险原则和合理修正原则等基本原则;提出“点位-行业-区域”逐层展开的城市安全风险评估程序,明确各层级的评估要点;提出城市安全风险评估方法,分别制定点位、行业风险修正规则,结合风险参数与情景构建开展基于风险矩阵法的点位风险评估和行业风险评估,采用加权计算法由行业风险评估结果叠加评估区域风险。结果表明:该方法能够从不同角度有效评估城市的风险状态,为不同层级的城市安全管理者明确风险管控重点提供决策依据。     

兽药抗生素潜在生态效应及其环境行为

在集约化畜禽养殖过程中,兽药抗生素被广泛地作为饲料添加剂,用于预防和治疗动物疾病以及促进动物生长。本文介绍了兽药抗生素在国内外的发展形势及其随着畜禽粪便排出体外的抗生素在环境中的残留和生态效应。最后,论述了兽药抗生素在环境中的行为特征,并重点介绍了在土壤中的降解行为和吸附解吸特征。     

旅游综合体开发——一种旅游房地产全新开发模式研究

随着产业结构升级,旅游结构从原有的单一旅游经济模式向多元化的、集合式的、综合性的旅游模式发展,产生了以旅游资源与土地为基础,以旅游休闲功能为主导,结合大型旅游休闲项目、高品质服务的配套设施、互动发展的休闲旅游地产等多功能的、集合式的土地利用模式及产业聚集模式。在观察和归纳大量这类开发实例的基础上定义了旅游综合体开发这一房地产全新开发模式的概念,分析了该模式的表现特征,总结性地提出开发的理论模式及应用模式,并在此基础上归纳出开发的战略措施。     

可持续发展理论三项进展

过去10年间,可持续发展理论和实践都取得重大进展。在这些进展当中,本文辨识出3个核心的概念:地球系统观、生态文明思想、低碳经济概念,对这3个看起来没有直接关联的概念分析了其中十分密切的理论联系。地球系统观的发展深刻地改变了人类对自身和所处地球环境的认识,被称为"第二次哥白尼革命",从而强化了可持续发展理论的科学基础;生态文明思想从根本上颠覆了工业文明的思想基础,深化了可持续发展理论的哲学和伦理学内涵;低碳经济概念是全球应对气候变化过程中提出的新的理念,以提高能效、减少排放和发展可再生能源为特征的经济发展模式是可持续发展理论在实践的具体化,并具有可操作性。3个概念都突出了地球系统作为一个整体来研究、开发、利用和保护;同时也都强调了对地球表层这个自然与社会剧烈交互作用的生态圈和人类圈的理解必须运用全新的视角和多学科的研究方法。深入理解这3个概念的内涵及相互关系是把握可持续发展理论10年进展的关键。     

Unsteadiness of COD in the Upper and Middle Reaches of Minjiang River

This paper explores and identifies the rules of the unsteady evolution of COD in the upper and middle reaches of Minjiang River through multi-scale analysis on the weekly COD data for the last six years provided by the Water Quality Monitoring Station,Minjiang River Bridge,Leshan City,Sichuan Province.The results of the wavelet analysis indicate that the COD index oscillates alternatively and differently at each time-scale in an oneyear cycle,and the density of COD,subjected to the runoff volume,the effects of Wenchuan Earthquake and agricultural seeding and industrial construction,etc.,is high in winter and spring,mild in summer and autumn.     

Broadband UV spectroscopy system used for monitoring of SO2 and NO emissions from thermal power plants

A gas monitoring system based on broadband absorption spectroscopic techniques in the ultraviolet region is described and tested. The system was employed in real-time continuous concentration measurements of sulfur dioxide (SO₂) and nitric oxide (NO) from a 220-ton h^?1 circulating fluidized bed (CFB) boiler in Shandong province, China. The emission coefficients (per kg of coal and per kWh of electricity) and the total emission of the two pollutant gases were evaluated. The measurement results showed that the emission concentrations of SO₂ and NO from the CFB boiler fluctuated in the range of 750–1300 mg m^?3 and 100–220 mg m^?3, respectively. Compared with the specified emission standards of air pollutants from thermal power plants in China, the values were generally higher for SO₂ and lower for NO. The relatively high emission concentrations of SO₂ were found to mainly depend on the sulfur content of the fuel and the poor desulfurization efficiency. This study indicates that the broadband UV spectroscopy system is suitable for industrial emission monitoring and pollution control.