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Journal of environmental Sciences 2016年第6期28卷 141-147页

作者： Hong Liu Shuying Tan Tong Yu Yang Liu Department of Civil and environmental Engineering University of Alberta

Sulfate reducing bacteria（SRB） play significant roles in anaerobic environments in oil sands mature fine tailings（MFTs）. Hydrogen sulfide（H2S） is produced during the biological sulfate reduction process. The production of toxic H2S is one of the concerns because it may hinder the landscape remediation efficiency of oil sands tailing ponds. In present study, the in situ activity and the community structure of SRB in MFT and gypsum amended MFT in two settling columns were investigated. Combined techniques of H2S microsensor and dissimilatory sulfite reductase β-subunit（dsrB） genes-based real time quantitative polymerase chain reaction（qPCR） were applied to detect the in situ H2S and the abundance of SRB. A higher diversity of SRB and more H2S were observed in gypsum amended MFT than that in MFT, indicating a higher sulfate reduction activity in gypsum amended MFT; in addition, the activity of SRB varied as depth in both MFT and gypsum amended MFT： the deeper the more H2S produced. Long-term plans for tailings management can be assessed more wisely with the information provided in this study.

关键词： Sulfate reducing bacteria Hydrogen sulfide Oil sands tailing Molecular biology Microsensor

Comparison between wave generation methods for numerical simulation of bimodal seas

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Water Science and Engineering 2016年第1期9卷 3-13页

作者： Daniel A.Thompson Harshinie Karunarathna Dominic Reeve Energy & environment research Group Zienkiewicz Centre for Computational Engineering Swansea UniversityBay Campus

This paper describes an investigation of the generation of desired sea states in a numerical wave model. Bimodal sea states containing energetic swell components can be coastal hazards along coastlines exposed to large oceanic fetches. Investigating the effects of long-period bimodal seas requires large computational domains and increased running time to ensure the development of the desired sea state. Long computational runs can cause mass stability issues due to the Stokes drift and wave reflection, which in turn affect results through the variation of the water level. A numerical wave flume, NEWRANS, was used to investigate two wave generation methods： the wave paddle method, allowing for a smaller domain; and the internal mass source function method, providing an open boundary allowing reflected waves to leave the domain. The two wave generation methods were validated against experimental data by comparing the wave generation accuracy and the variance of mass in the model during simulations. Results show that the wave paddle method not only accurately generates the desired sea state but also provides a more stable simulation, in which mass fluctuation has less of an effect on the water depth during the long-duration simulations. As a result, it is suggested that the wave paddle method with active wave absorption is preferable to the internal wave maker option when investigating intermediate-depth long-period bimodal seas for long-duration simulations.

关键词： Wave modeling Wave generation RANS Swell wave Bimodal sea Long-period waves

Atmospheric Precursors of and Response to Anomalous Arctic Sea Ice in CMIP5 Models

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Advances in Atmospheric Sciences 2018年第1期35卷 27-37页

作者： Michael KELLEHER James SCREEN College of Engineering Mathematics and Physical SciencesUniversity of Exeter

This study examines pre-industrial control simulations from CMIP5 climate models in an effort to better understand the complex relationships between Arctic sea ice and the stratosphere, and between Arctic sea ice and cold winter temperatures over Eurasia. We present normalized regressions of Arctic sea-ice area against several atmospheric variables at extended lead and lag times. Statistically significant regressions are found at leads and lags, suggesting both atmospheric precursors of, and responses to, low sea ice; but generally, the regressions are stronger when the atmosphere leads sea ice, including a weaker polar stratospheric vortex indicated by positive polar cap height anomalies. Significant positive midlatitude eddy heat flux anomalies are also found to precede low sea ice. We argue that low sea ice and raised polar cap height are both a response to this enhanced midlatitude eddy heat flux. The so-called "warm Arctic, cold continents" anomaly pattern is present one to two months before low sea ice, but is absent in the months following low sea ice, suggesting that the Eurasian cooling and low sea ice are driven by similar processes. Lastly, our results suggest a dependence on the geographic region of low sea ice, with low Barents–Kara Sea ice correlated with a weakened polar stratospheric vortex, whilst low Sea of Okhotsk ice is correlated with a strengthened polar vortex. Overall, the results support a notion that the sea ice, polar stratospheric vortex and Eurasian surface temperatures collectively respond to large-scale changes in tropospheric circulation.

关键词： sea ice–atmosphere coupling stratosphere–troposphere coupling atmospheric circulation Eurasian climate

Performance Assessment and Outlook of China＇s Emission-Trading Scheme

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Engineering 2016年第4期2卷 398-401页

作者： Dabo Guan Yuli Shan Zhu Liu Kebin He Tyndall Centre for Climate Change research School of International Development University of East Anglia Norwich NR4 7TJ UK Resnick Sustainability Institute California Institute of Technology Pasadena CA 91125 USA State Key Joint Laboratory of environmentul Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China

1. Overview China overtook the US as the world＇s top emitter in 2007, and produced 1.5 times the emissions of the US by 2013 [1 ]. At pres- ent, China＇s emissions make up over a quarter of the global total. China is expected to produce three times the emissions of the US by 2030 [2]. Indeed, China＇s role and efforts in CO2 reductions matter greatly for the peaking of global emissions, even without further emission leakages to less-developed regions or countries. China recently announced the launch of a nation-wide emissiontrading scheme （ETS） starting in 2017 [3] in order to help deliver its emission peak by 2030. A number of climate policies in China are ongoing, and require a full performance review, effective coordination, and appropriate implementation of planning and monitoring measures along with any newly added mechanisms. This paper utilizes the latest energy and emission data to explore the impact of emission trading as a policy driver toward absolute emission and emission intensity changes in China and in its seven provinces or municipalities.

关键词：排放交易绩效评价中国

Nontargeted identification of peptides and disinfection byproducts in water

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Journal of environmental Sciences 2016年第4期28卷 259-266页

作者： Yanan Tang Ying Xu Feng Li Lindsay Jmaiff Steve E.Hrudey Xing-Fang Li Division of Analytical and environmental Toxicology Department of Laboratory Medicine and PathologyUniversity of Alberta Department of Computer Science University of Alberta

A broad range of organic compounds are known to exist in drinking water sources and serve as precursors of disinfection byproducts（DBPs）.Epidemiological findings of an association of increased risk of bladder cancer with the consumption of chlorinated water has resulted in health concerns about *** are thought to be an important category of DBP precursors in ***,little is known about the actual presence of peptides and their DBPs in drinking water because of their high sample complexity and low *** address this challenge and identify peptides and non-chlorinated/chlorinated peptide DBPs from large sets of organic compounds in water,we developed a novel high throughput analysis strategy,which integrated multiple solid phase extraction（SPE）,high performance liquid chromatography（HPLC）separation,and non-target identification using precursor ion exclusion（PIE）high resolution mass spectrometry（MS）.After MS analysis,structures of candidate compounds,particularly peptides,were obtained by searching against the Human Metabolome Database（HMDB）.Using this strategy,we successfully detected 625 peptides（out of 17,205 putative compounds）and 617 peptides（out of 13,297）respectively in source and finished water *** source and finished water samples had 501 peptides and amino acids in *** remaining 116 peptides and amino acids were unique to the finished *** a subset of 30 putative compounds for which standards were available,25 were confirmed using HPLC-MS *** analyzing the peptides identified in source and finished water,we successfully confirmed three disinfection reaction pathways that convert peptides into toxic DBPs.

关键词： Nontargeted detection Water analysis Mass spectrometry Peptide Disinfection byproducts

Belgica antarctica(Diptera: Chironomidae): A natural modelorganism for extreme environments

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Insect Science 2022年第1期29卷 2-20页

作者： Iryna Kozeretska Svitlana Serga Pavlo Kovalenko Volodymyr Gorobchyshynand Peter Convey National Antarctic Scientific Center of Ukraine 01601Taras Shevchenko blv.16KyivUkraine Taras Shevchenko National Universityof Kyiv Department General and Medical Genetics01601Volodymyrska str.64/13KyivUkraine State Institution«Institute for Evolu-tionary Ecology of the National Academy of Sciences of Ukraine» Department of Population Dynamics03143Lebedeva str.37KyivUkraine and4British Antarctic SurveyNERCHigh CrossMadingley RoadCambridge CB30ETUnited Kingdom

Belgica antarctica(Diptera:Chironomidae),a brachypterous midge endemicto the maritime Antarctic,was first described in *** more than a century of study,a vast amount of information has been compiled on the species(3750000 Google searchresults as of January 10,2021),encompassing its ecology and biology,life cycle and re-production,polytene chromosomes,physiology,biochemistry and,increasingly,***2014,***’s genome was sequenced,further boosting *** develop-mental stages can be cultured successfully in the *** together,this wealthof information allows the species to be viewed as a natural model organism for studies ofadaptation and function in extreme environments.

关键词： Belgica antarctica Chironomidae stress adaptation Antarctica

The challenges of developing an open source, standards-based technology stack to deliver the latest UK climate projections

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International Journal of Digital Earth 2012年第1期5卷 43-62页

作者： Ag Stephens Philip James David Alderson Stephen Pascoe Simon Abele Alan Iwi Peter Chiu The British Atmospheric Data Centre DidcotUK School of Civil Engineering and Geosciences Newcastle UniversityNewcastle-Upon-TyneUK

To improve the understanding of local and regional effects of climate change,the UK government supported the development of new climate *** Met Office Hadley Centre produced a sophisticated set of probabilistic projections for future *** paper discusses the design and implementation of an interactive website to deliver those projections to a broad user *** interface presents complex data sets,generates on-the-fly products and schedules jobs to an offline weather generator capable of outputting gigabytes of data in response to a single request.A robust and scalable physical architecture was delivered through significant use of open source technologies and open standards.

关键词： geoinformatics digital earth climate change geospatial science geospatial data integration

Impact of rewilding,species introductions and climate change on the structure and function of the Yukon boreal forest ecosystem

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Integrative Zoology 2018年第2期13卷 123-138页

作者： Rudy BOONSTRA Stan BOUTIN Thomas S.JUNG Charles J.KREBS Shawn TAYLOR Department of Biological Sciences University of Toronto ScarboroughTorontoOntarioCanada Department of Biological Sciences University of AlbertaEdmontonAlbertaCanada Department of environment Government of YukonWhitehorseYukonCanada Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada

Community and ecosystem changes are happening in the pristine boreal forest ecosystem of the Yukon for 2 ***,climate change is affecting the abiotic environment(temperature,rainfall and growing season)and driving changes in plant productivity and predator-prey ***,simultaneously change is occurring because of mammal species reintroductions and *** key ecological question is the impact these faunal changes will have on trophic *** productivity in the boreal forest is increasing because of climatic warming,but plant species composition is unlikely to change significantly during the next 50-100 *** 9-10-year population cycle of snowshoe hares will persist but could be reduced in amplitude if winter weather increases predator hunting *** rodents have increased in abundance because of increased vegetation *** ground squirrels have disappeared from the forest because of increased predator hunting efficiency associated with shrub *** have occurred for 2 reasons:human reintroductions of large ungulates and natural recolonization of mammals and birds extending their geographic *** deliberate rewilding of wood bison(Bison bison)and elk(Cervus canadensis)has changed the trophic structure of this boreal ecosystem very *** natural range expansion of mountain lions(Puma concolor),mule deer(Odocoileus hemionus)and American marten(Martes americana)should have few ecosystem *** potential changes will require long-term monitoring studies and experiments on a scale we rarely deem *** affected by climate change,species reintroductions and human alteration of habitats cannot remain stable and changes will be critically dependent on food web interactions.

关键词： community stability introduced species population cycles trophic dynamics

Extreme Wind Variability and Wind Map Development in Western Java,Indonesia

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International Journal of Disaster Risk Science 2022年第3期13卷 465-480页

作者： Muhammad Rais Abdillah Prasanti Widyasih Sarli Hafidz Rizky Firmansyah Anjar Dimara Sakti Faiz Rohman Fajary Robi Muharsyah Gian Gardian Sudarman Atmospheric Science research Group Faculty of Earth Science and TechnologyInstitut Teknologi BandungBandung40132Indonesia Structural Engineering research Group Faculty of Civil and Environmental EngineeringInstitut Teknologi BandungBandung40132Indonesia Center for Infrastructures and Built environment Institut Teknologi BandungBandung40132Indonesia Civil Engineering Department Faculty of Civil and Environmental EngineeringInstitut Teknologi BandungBandung40132Indonesia Remote Sensing and Geographic Information Science research Group Faculty of Earth Sciences and TechnologyInstitut Teknologi BandungBandung40132Indonesia Center for Remote Sensing Institut Teknologi BandungBandung40132Indonesia Center for Climate Change and Information The Agency for MeteorologyClimatology and Geophysics of the Republic of Indonesia(BMKG)Jakarta10720Indonesia Subdivision for Executive Secretary Administration The Agency for MeteorologyClimatology and Geophysics of the Republic of Indonesia(BMKG)Jakarta10720Indonesia Earth Science Department Faculty of Earth Science and TechnologyInstitut Teknologi BandungBandung40132Indonesia

Wind-related disasters are one of the most frequent disasters in *** can cause severe damages of residential construction,especially in the world's most populated island of *** the characteristics of extreme winds is crucial for mitigating the disasters and for defining structural design *** study investigated the spatiotemporal variations of extreme winds and pioneered a design wind map in Indonesia by focusing on western *** on gust data observed in recent years from 24 stations,the extreme winds exhibit a clear annual cycle where northwestern and southeastern sides of western Java show out-of-phase relationship due to reversal ***,extreme wind occurrences are mostly affected by small-scale weather systems,regardless of seasons and *** build the wind map,we used bias-corrected gust from ERA5 and applied the Gumbel method to predict extreme winds with different return *** wind map highlights some drawbacks of the current national design standards,which use single wind speed values regardless of location and return *** a fundamental improvement for wind design,this study will benefit disaster risk mapping and other applications that require extreme wind speed distribution.

关键词： ERA5 reanalysis Extreme wind Mixed weather system Tropical climate

Numerical simulations of water flow and contaminants transport near mining wastes disposed in a fractured rock mass

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International Journal of Mining Science and Technology 2015年第1期25卷 37-45页

作者： Ben Abdelghani Farouk Aubertin Michel Simon Richard Therrien René Department of Civil Engineering Institut Supérieur de la Construction et de l’Urbanisme research Institute on Mines and the environment (RIME) Polytechnique Montreal Department of Geology and Geological Engineering University Laval

A numerical tool, called Hydro-Geosphere, was used to simulate unsaturated water flow and contaminants migration around an open pit filled with mining wastes. Numerical simulations had been carried out to assess the influence of various factors on water flow and solute transport in and around the surface openings including recharge, properties of the waste material and presence of fractures in the surrounding rock mass. The effect of the regional hydraulic gradient was also investigated. The analyses were conducted by simulating various 2D cases using experimentally obtained material properties and controlled boundary conditions. The effects of the hydrogeological properties of the filling material(i.e., water retention curve and hydraulic conductivity function), fracture network characteristics and conductivity of the joints were assessed. The results illustrate that fractures control water flow and contaminants transport around the waste disposal area. A fracture network can desaturate the system and improve the regional gradient effect.

关键词： Hydro-GeosphereNumerical modellingUnsaturated water flowContaminants transportTailingsWaste rocks