Performance of different macrophytes in the decontamination of and electricity generation from swine wastewater via an integrated constructed wetland-microbial fuel cell process

Plants constitute a major element of constructed wetlands(CWs).In this study,a coupled system comprising an integrated vertical flow CW(IVCW) and a microbial fuel cell(MFC) for swine wastewater tre atment was developed to research the effects of macrophytes commonly employed in CWs,Canna indica,Acorus calamus,and Ipomoea aquatica,on decontamination and electricity production in the system.Because of the different root types and amounts of oxygen released by the roots,the rates of chemical oxygen demand(COD) and ammonium nitrogen(NH_4~+-N) removal from the swine wastewater differed as well.In the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,the COD removal rates were 80.20%,88.07%,84.70%,and 82.20%,respectively,and the NH_4~+-N removal rates were 49.96%,75.02%,70.25%,and 68.47%,respectively.The decontamination capability of the Canna indica system was better than those of the other systems.The average output voltages were 520±42,715±20,660±27,and 752±26 mV for the unplanted,Canna indica,Acorus calamus,and Ipomoea aquatica systems,respectively,and the maximum power densities were 0.2230,0.4136,0.3614,and0.4964 W/m~3,respectively.Ipomoea aquatica had the largest effect on bioelectricity generation promotion.In addition,electrochemically active bacteria,Geobacter and Desulfuromonas,were detected in the anodic biofilm by high-throughput sequencing analysis,and Comamonas(Proteobacteria),which is widely found in MFCs,was also detected in the anodic biofilm.These results confirmed the important role of plants in IVCW-MFCs.     

Big data analytics capabilities for reinforcing green production and sustainable firm performance: the moderating role of corporate reputation and supply chain innovativeness

Environmental Science and Pollution Research - The literature review lacks empirical studies on the role of big data analytics (BDA) and green technological innovation capabilities (GTICs) in...     

Toxicity of urban highway runoff in Shanghai to Zebrafish (Danio rerio) embryos and luminous bacteria (Vibrio qinghaiensis.Q67)

Pollution from urban highway runoff has been identified as one of the major causes of the deterioration of receiving water quality. The purpose of this study is to assess the toxicity of urban storm water samples in Shanghai using the zebrafish (Danio rerio) embryo test and the bacterial luminescence (Vibrio qinghaiensis) assay. The toxicity of highway runoff from seventeen storm events was investigated in both grab and composite samples. Zebrafish embryos were exposed to the runoff samples and development parameters including lethality, spontaneous movements in 20 s, heart beat rate, hatching rate, and abnormality of zebrafish embryos were observed after 24, 48, 72, and 96 h of exposure. Inhibition rates of luminescence intensity were also recorded. The results showed that in the zebrafish embryo toxicity tests, both grab and composite samples increased the lethality, reduced the percentage with spontaneous movements and heart beats, inhibited the hatching of embryos, and induced morphological abnormalities. In the Vibrio qinghaiensis toxicity test, all the grab samples inhibited the luminescence, while some of the composite samples promoted it, which indicated that different types of toxicants might have been affecting the species. The multivariate statistics analysis indicated that heavy metal (zinc, manganese, and copper) and PAHs might mainly contribute to the toxicity of runoff samples.     

Exploring soil erosion trajectories and their divergent responses to driving factors: a model-based contrasting study in highly eroded mountain areas

Environmental Science and Pollution Research - Soil erosion threatens environmental sustainability worldwide. Exploring the trajectories of soil erosion and associated drivers is of great...     

一株耐铬细菌的鉴定及其还原铬性能分析

从浙江温州工业区六价铬废水污染的土壤中采样分离得到一株耐铬细菌Y73.16S rRNA基因序列分析表明,该菌株为Staphylococcus(葡萄球菌)属菌,最高可在加有1600 mg·L^-1六价铬(K₂Cr₂O₇)的 LB培养基中生长.该菌为好氧生长,但在3种不同的氧压力下,包括有氧、无氧和兼性无氧(先有氧生长)的条件下都可以还原六价铬,而在兼性无氧(先有氧生长)的条件下达到最高还原效率,可在96 h内将1000 mg·L^-1的六价铬还原83%.另外,该菌株能在较宽的pH值(5~11)和温度(10~50℃)范围内还原六价铬,而最佳反应条件是pH=7 和30℃.随着接种量的增加,六价铬的还原率增加,但接种量超过10%时再增加接种量对六价铬还原的影响不明显.供试的大多数金属离子(50 mg·L^-1)对该菌株还原六价铬的影响也不明显.上述结果说明,菌株Y73有其独特的还原铬性能,以及在处理六价铬污染废水中的应用潜力.     

Nitrogen cycle of a typical Suaeda salsa marsh ecosystem in the Yellow River estuary

The nitrogen (N) biological cycle of the Suaeda salsa marsh ecosystem in the Yellow River estuary was studied during 2008 to 2009. Results showed that soil N had significant seasonal fluctuations and vertical distribution. The N/P ratio (15.73±1.77) of S. salsa was less than 16, indicating that plant growth was limited by both N and P. The N absorption coefficient of S. salsa was very low (0.007), while the N utilization and cycle coefficients were high (0.824 and 0.331, respectively). The N turnover among compartments of S. salsa marsh showed that N uptake from aboveground parts and roots were 2.539 and 0.622 g/m2, respectively. The N translocation from aboveground parts to roots and from roots to soil were 2.042 and 0.076 g/m2, respectively. The N translocation from aboveground living bodies to litter was 0.497 g/m2, the annual N return from litter to soil was far less than 0.368 g/m2, and the net N mineralization in topsoil during the growing season was 0.033 g/m2. N was an important limiting factor in S. salsa marsh, and the ecosystem was classified as unstable and vulnerable. S. salsa was seemingly well adapted to the low-nutrient status and vulnerable habitat, and the nutrient enrichment due to N import from the Yellow River estuary would be a potential threat to the S. salsa marsh. Excessive nutrient loading might favor invasive species and induce severe long-term degradation of the ecosystem if human intervention measures were not taken. The N quantitative relationships determined in our study might provide a scientific basis for the establishment of effective measures.     

煤矸石的环境危害与综合利用途径

本文主要介绍了我国煤矸石的现状,分析了煤矸石对自然环境的危害。探讨了利用煤矸石的有效途径。     

大型浮顶储罐雷击事故分析及防雷技术研究

通过对典型大型浮顶储罐雷击事故分析,总结了这些事故的共性问题。结合浮顶储罐雷击形式及雷电火花放电研究,分析了大型浮顶储罐雷击火灾事故的机理。岚山输油站在等电位连接、一次密封形式结构等方面进行技术改造,经过验证这些措施有效减少了大型浮顶储罐火灾事故的发生。     

不同给水管材对管壁附着生物膜铅、镉的解吸动力学研究

给水管壁生物膜会吸附水中的重金属元素积累在管壁生物膜中,在受到扰动时释放回到水体,危害饮用水水质安全。试验以上海管网末梢水为实验对象,研究了PVC、铸铁和紫铜等三种管材上生物膜对铅、镉的解吸特性。结果表明,PVC、铸铁和紫铜附着生物膜对铅的解吸容量qe分别为:5.92211μmol·m^-2、128.3051μmol·m^-2和21.1808,解吸速率常数k分别为:0.001060 m^2·μmol^-1·min^-1、0.000041 m^2·μmol^-1·min^-1和0.000503 m^2·μmol^-1·min^-1,对于镉元素三种材质的解吸容量qe分别为:14.71519μmol·m^-2、18.50481μmol·m^-2和2.25225μmol·m^-2;解吸速率常数k分别为:0.000102 m^2·μmol^-1·min^-1、0.001070 m^2·μmol^-1·min^-1和0.000103 m^2·μmol^-1·min^-1。     

Utilization of MSWI fly ash as partial cement or sand substitute with focus on cementing efficiency and health risk assessment

• Washed MSWI fly ash was used as partial cement or sand substitute. • Sand replacing is beneficial for strength, while cement replacement reduces strength. • Cementing efficiency factor and mortar pore structure explain the strength results. • Health risk assessment was conducted for MSWI fly ash blended cement mortar. • CR and HI contributed by different exposures and heavy metals were analyzed. The strength of cement substituted mortar decreases with the increase in fly ash amount, whereas the strength increases when the fly ash is blended as sand substitute. A mortar with highest strength (compressive strength= 30.2 Mpa; flexural strength= 7.0 Mpa) was obtained when the sand replacement ratio was 0.75%. The k value (cementing efficiency) of fly ash varied between 0.36 and 0.15 for the fly ash fraction in binder between 5% and 25%. The k values of fly ash used for sand replacement were all significantly above that used for cement substitution. The macropores assigned to the gaps between particles decreased when the fly ash was used as sand replacement, providing an explanation for the strength enhancement. The waste-extraction procedure (toxicity-sulphuric acid and nitric acid method (HJ/T 299-2007)) was used to evaluate metal leaching, indicating the reuse possibility of fly ash blended mortar. For the mortar with the mass ratio of fly ash to binder of 0.5%, the carcinogenic risks (CR) and non-carcinogenic hazard quotient (HQ) in sensitive scenario for blended mortar utilization were 9.66 × 10^-7 and 0.06, respectively; these results were both lower than the threshold values, showing an acceptable health risk. The CR (9.89 × 10^-5) and HQ (3.89) of the non-sensitive scenario for fly ash treatment exceeded the acceptable threshold values, indicating health risks to onsite workers. The main contributor to the carcinogenic and non-carcinogenic risk is Cr and Cd, respectively. The CR and HQ from inhalation was the main route of heavy metal exposure.