A review of bioretention components and nutrient removal under different climates—future directions for tropics

Bioretention systems have been implemented as stormwater best management practices (BMPs) worldwide to treat non-point sources pollution. Due to insufficient research, the design guidelines for bioretention systems in tropical countries are modeled after those of temperate countries. However, climatic factors and stormwater runoff characteristics are the two key factors affecting the capacity of bioretention system. This paper reviews and compares the stormwater runoff characteristics, bioretention components, pollutant removal requirements, and applications of bioretention systems in temperate and tropical countries. Suggestions are given for bioretention components in the tropics, including elimination of mulch layer and submerged zone. More research is required to identify suitable additives for filter media, study tropical shrubs application while avoiding using grass and sedges, explore function of soil faunas, and adopt final discharged pollutants concentration (mg/L) on top of percentage removal (%) in bioretention design guidelines.

     

Assessment of multiple anthropogenic contaminants and their potential genotoxicity in the aquatic environment of Plitvice Lakes National Park,Croatia

In this study, the influence of anthropogenic pollution on the aquatic environment of Plitvice Lakes National Park (PLNP) was investigated during 2011–2012 using a combination of chemical and cytogenetic analyses. Four groups of major contaminants [(volatile organic compounds: benzene, toluene, ethylbenzene, and xylenes (BTEX); persistent organochlorine pollutants: organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs); major and trace elements; anthropogenic radionuclides (⁹⁰Sr, ¹³⁴Cs, and ¹³⁷Cs)] were determined in three aquatic compartments (water, sediment, fish). Mass fractions of inorganic constituents in different compartments reflected the geological background of the area, indicating their origin from predominantly natural sources. Levels of volatile and persistent organic compounds in water and fish, respectively, were very low, at levels typical for remote pristine areas. Analysis of anthropogenic radionuclides in water and sediment revealed elevated activity concentrations of ¹³⁷Cs in water, and measurable ¹³⁴Cs in the upper sediment layers from April 2011, possibly as a consequence of the Fukushima nuclear accident in March 2011. The potential genotoxicity of river and lake water and lake sediment was assessed under laboratory conditions using the alkaline comet assay on human peripheral blood lymphocytes, and measured levels of primary DNA damage were within acceptable boundaries. The results showed that despite the protected status of the park, anthropogenic impact exists in both its terrestrial and aquatic components. Although contaminant levels were low, further monitoring is recommended to make sure that they will not rise and cause potentially hazardous anthropogenic impacts.     

Study on turbulence characteristics and sensitivity of quadrant analysis to threshold level in Lake Taihu

Environmental Science and Pollution Research - The identification of coherent structures is very important in investigating the sediment transport mechanism and controlling the eutrophication in...     

雷电灾害对储罐影响的定量风险评估方法研究

基于定量化风险评估方法,研究雷电灾害对金属储罐的一种破坏方式———雷电流高温造成储罐的金属壳熔融破损,进而造成储罐失效事故。以某储罐区的装有石油的金属储罐为研究对象,对雷击储罐后,造成储罐破裂,引发池火这一事件链进行了分析,验证了该方法的可行性。     

SoilTrEC: a global initiative on critical zone research and integration

Soil is a complex natural resource that is considered non-renewable in policy frameworks, and it plays a key role in maintaining a variety of ecosystem services (ES) and life-sustaining material cycles within the Earth's Critical Zone (CZ). However, currently, the ability of soil to deliver these services is being drastically reduced in many locations, and global loss of soil ecosystem services is estimated to increase each year as a result of many different threats, such as erosion and soil carbon loss. The European Union Thematic Strategy for Soil Protection alerts policy makers of the need to protect soil and proposes measures to mitigate soil degradation. In this context, the European Commission-funded research project on Soil Transformations in European Catchments (SoilTrEC) aims to quantify the processes that deliver soil ecosystem services in the Earth's Critical Zone and to quantify the impacts of environmental change on key soil functions. This is achieved by integrating the research results into decision-support tools and applying methods of economic valuation to soil ecosystem services. In this paper, we provide an overview of the SoilTrEC project, its organization, partnerships and implementation.     

生物质材料预处理餐饮废水

采用4种廉价的生物质材料（水葫芦、柚子皮、木屑、核桃壳）用于餐饮废水的预处理。通过静态烧杯实验,研究了各生物质材料预处理废水的效果及最佳处理条件。结果表明,生物质材料对废水中COD的去除率均在45％以上,油脂吸附量为4～16mg／g,最优吸附材料为水葫芦,COD去除率达65％,油脂吸附量为16mg／g;水葫芦和柚子皮的最佳处理条件为：粒径〈0．2mm,投加量为20g／L,废水pH为4,处理时间为2h,温度为20℃;木屑和核桃壳的最佳实验条件为：粒径〈0．2mm,投加量为28g／L,pH为2,处理时间为2．5h,温度为20℃。生物质对餐饮废水的预处理,为废水中大量有机物和废弃油脂的去除提供了新思路和途径。     

SDS改性沸石吸附结晶紫简

以表面活性剂十二烷基硫酸钠（SDS）对沸石进行改性,改性后的沸石对结晶紫溶液进行吸附,以紫外可见分光光度计分析最佳吸附条件。实验结果表明,在30℃,SDS改性沸石投入量为0.25 g;吸附平衡时间为1 h;pH为8的条件下,对含50 mg/L结晶紫染料的去除率可达到92.6%,吸附量达到4.63 mg/g。SDS改性沸石吸附结晶紫的等温吸附曲线与Henry型和Freundlich型均拟合较好。热力学参数计算结果表明,吸附符合自发吸热过程。     

脱氮副球菌YF1微生物燃料电池生物阴极脱氮和产电

以脱氮副球菌YF1构建纯种生物阴极微生物燃料电池(microbial fuel cell,MFC)进行脱氮和产电机理的研究。研究结果发现,阴极碳氮比、pH值对产电和脱氮效率有明显影响。当MFC的阴极运行条件pH值为8.0,碳氮比为20时,运行时间15 h时,脱氮率高达100%,输出电压为150 mV。上述结果表明,微生物燃料电池运行过程中,细菌降解硝酸根的机理为将硝酸根还原为N2或者直接将其作为自身的营养物质而利用。循环伏安(CV)与扫描电镜(SEM)的结果表明,在微生物燃料电池运行中,副球菌YF1通过接触导电作为产电的电子供体。     

抗侵蚀型生态沟渠构建及其稻田应用效果

根据沟渠水力学和工程力学特征,通过引进三维植物网护坡技术,构建了一种抗侵蚀型稻田生态沟渠,横断面0.9 m2,沟壁和沟底水生植物覆盖度分别为62.8%和35.3%,沟壁抗坡面侵蚀强度较土质沟渠可提高2倍以上,在优化污染物拦截去除功能的同时,大大延长了其使用寿命。稻田应用实验表明,径流排水停留时间超过48 h后,SS、TN和TP去除率分别达59.5%、57.8%和45.3%,配置比例按照1 hm2水稻田配300 m该型生态沟渠实施,则超过80%以上的稻田径流排水能够得到有效处理。该型生态沟渠工程造价约245元/m,接近传统混凝土排水渠单价,经近2年的运行观测,沟渠系统结构稳定,净化植物长势良好。