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Current Zoology 2010年第3期56卷 285-299页

作者： Martine E.MAAN Ole SEEHAUSEN Institute of Ecology & Evolution University of Bern eawag Centre of Ecology Evolution and Biogeochemistry(CEEB)

The theory of ecological speciation suggests that assortative mating evolves most easily when mating preferences aredirectly linked to ecological traits that are subject to divergent selection. Sensory adaptation can play a major role in this process,because selective mating is often mediated by sexual signals: bright colours, complex song, pheromone blends and so on. Whendivergent sensory adaptation affects the perception of such signals, mating patterns may change as an immediate consequence.Alternatively, mating preferences can diverge as a result of indirect effects: assortative mating may be promoted by selectionagainst intermediate phenotypes that are maladapted to their (sensory) environment. For Lake Victoria cichlids, the visual environmentconstitutes an important selective force that is heterogeneous across geographical and water depth gradients. We investigatethe direct and indirect effects of this heterogeneity on the evolution of female preferences for alternative male nuptial colours(red and blue) in the genus Pundamilia. Here, we review the current evidence for divergent sensory drive in this system, extractgeneral principles, and discuss future perspectives [Current Zoology 56 (3): 285-299, 2010].

关键词：模型系统丽鱼科物种分化视觉适应机制交配模式视觉环境维多利亚湖

Hydraulic characteristics of an anaerobic baffled reactor as onsite wastewater treatment system

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Journal of Environmental Sciences 2010年第9期22卷 1319-1326页

作者： Yuttachai Sarathai Thammarat Koottatep Antoine Morel School of Environment Resources and Development Asian Institute of Technology eawag:Swiss Federal Institute for Aquatic Science & Technology Department for Water and Sanitation in Developing Countries(Sandec)

The feasibility of using anaerobic baffled reactor （ABR） as onsite wastewater treatment system was discussed. The ABR consisted of one sedimentation chamber and three up-flow chambers in series was experimented under different peak flow factors （PFF of 1 to 6）, superficial gas velocities （between 0.6 and 3.1 cm/hr） and hydraulic retention times （HRT）（24, 36 and 48 hr）. Residence time distribution （RTD） analyses were carded out to investigate the hydraulic characteristics of the ABR. It was found that the PFF resulted in hydraulic dead space. The dead space did not exceed 13% at PFF of 1, 2 and 4 while there was 2-fold increase （26%） at PFF of 6. Superficial gas velocities did not result in more （biological） dead space. The mixing pattern of ABR tended to be a completely- mixed reactor when PFF increased. Superficial gas velocities did not affect mixing pattern. The effects of PFF on mixing pattern could be minimized by higher HRT （48 hr）. The tank-in-series （TIS） model （N = 4） was suitable to describe the hydraulic behaviour of the studied system. The HRT of 48 hr was able to maintain the mixing pattern under different flow patterns, introducing satisfactory hydraulic efficiency. Chemical oxygen demand （COD） and total suspended solids （TSS） removals under all flow patterns were achieved more than 85% and 90%, respectively. The standard deviation of effluent COD and TSS concentration did not exceed 15 mg/L.

关键词： anaerobic baffled reactor dead space hydraulic characteristics onsite system peak flow factor

Estimating water deficit and its uncertainties in water-scarce area using integrated modeling approach

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Water Science and Engineering 2012年第4期5卷 450-463页

作者： Shou-ke WEI eawag the Swiss Federal Institute of Aquatic Science and Technology Department of Forest Resources Management University of British Columbia Emodlogic Technology Inc.

Accurate assessment of water deficit and related uncertainties in water-scarce areas is strategically important in various fields of water resources management. This study developed a hybrid approach integrating conceptual water balance model and econometric regression to estimate water shortage and its related uncertainties in water-scarce areas. This hybrid approach was used to assess the agricultural water deficit of Beijing, an extremely water-scarce area in China. A predictive model of agricultural water demand was developed using the stepwise multiple regression method, and was validated by comparing the predicted values with observed data. Scenario analysis was employed to investigate the uncertainties of agricultural water shortage and agricultural water demand. This modeling approach can assist water administration in creating sustainable water allocation strategies in water-scarce areas.

关键词： water deficit hybrid model conceptual water balance model stepwise multipleregression method uncertainty Beo＇ing

Guided by the principles of microbiome engineering:Accomplishments and perspectives for environmental use

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mLife 2022年第4期1卷 382-398页

作者： Haiyang Hu Miaoxiao Wang Yiqun Huang Zhaoyong Xu Ping Xu Yong Nie Hongzhi Tang State Key Laboratory of Microbial Metabolism and School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghaiChina Department of Environmental Systems Science ETH ZürichZürichSwitzerland Department of Environmental Microbiology ETH ZürichEawagSwitzerland College of Engineering Peking UniversityBeijingChina.

Although the accomplishments of microbiome engineering highlight its significance for the targeted manipulation of microbial communities,knowledge and technical gaps still limit the applications of microbiome engineering in biotechnology,especially for environmental use.Addressing the environmental challenges of refractory pollutants and fluctuating environmental conditions requires an adequate understanding of the theoretical achievements and practical applications of microbiome engineering.Here,we review recent cutting-edge studies on microbiome engineering strategies and their classical applications in bioremediation.Moreover,a framework is summarized for combining both top-down and bottom-up approaches in microbiome engineering toward improved applications.A strategy to engineer microbiomes for environmental use,which avoids the build-up of toxic intermediates that pose a risk to human health,is suggested.We anticipate that the highlighted framework and strategy will be beneficial for engineering microbiomes to address difficult environmental challenges such as degrading multiple refractory pollutants and sustain the performance of engineered microbiomes in situ with indigenous microorganisms under fluctuating conditions.

关键词： bioremediation energy production environmental microbiology microbiome engineering

The evolutionary ecology of symbiont-conferred resistance to parasitoids in aphids

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Insect Science 2014年第3期21卷 251-264页

作者： Christoph Vorburger Institute of Integrative Biology ETH Zǖrich Universitātstrasse 16 8092 Zǖdch eawag Swiss Federal Institute of Aquatic Science and Technology Uberlandstrasse 133 8600 Dǖbendoàf Switzerland

Aphids may harbor a wide variety of facultative bacterial endosymbionts. These symbionts are transmitted maternally with high fidelity and they show horizontal trans-mission as well, albeit at rates too low to enable infectious spread. Such symbionts need to provide a net fitness benefit to their hosts to persist and spread. Several symbionts haveachieved this by evolving the ability to protect their hosts against parasitoids. Reviewing empirical work and some models, I explore the evolutionary ecology of symbiont-conferredresistance to parasitoids in order to understand how defensive symbiont frequencies are maintained at the intermediate levels observed in aphid populations. I further show thatdefensive symbionts alter the reciprocal selection between aphids and parasitoids by augmenting the heritable variation for resistance, by increasing the genetic specificity of thehost-parasitoid interaction, and by inducing environment-dependent trade-offs. These effects are conducive to very dynamic, symbiont-mediated coevolution that is driven by frequency-dependent selection. Finally I argue that defensive symbionts represent a problem for biological control of pest aphids, and I propose to mitigate this problem byexploiting the parasitoids＇ demonstrated ability to rapidly evolve counteradaptations to symbiont-conferred resistance.

关键词： aphids biological control coevolution genotype × genotype interaction Hamiltonella defensa parasitoid resistance symbiosis

Substrate availability and toxicity shape the structure of microbial communities engaged in metabolic division of labor

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mLife 2022年第2期1卷 131-145页

作者： Miaoxiao Wang Xiaoli Chen Yue-Qin Tang Yong Nie Xiao-Lei Wu Department of Energy&Resources Engineering College of EngineeringPeking UniversityBeijingChina Department of Environmental Systems Science ETH ZurichZürichSwitzerland Department of Environmental Microbiology EawagDübendorfSwitzerland Department of Environmental Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengduChina Institute of Ocean Research Peking UniversityBeijingChina Institute of Ecology Peking UniversityBeijingChina

Metabolic division of labor(MDOL)represents a widespread natural phenomenon,whereby a complex metabolic pathway is shared between different strains within a community in a mutually beneficial manner.However,little is known about how the composition of such a microbial community is regulated.We hypothesized that when degradation of an organic compound is carried out via MDOL,the concentration and toxicity of the substrate modulate the benefit allocation between the two microbial populations,thus affecting the structure of this community.We tested this hypothesis by combining modeling with experiments using a synthetic consortium.Our modeling analysis suggests that the proportion of the population executing the first metabolic step can be simply estimated by Monod-like formulas governed by substrate concentration and toxicity.Our model and the proposed formula were able to quantitatively predict the structure of our synthetic consortium.Further analysis demonstrates that our rule is also applicable in estimating community structures in spatially structured environments.Together,our work clearly demonstrates that the structure of MDOL communities can be quantitatively predicted using available information on environmental factors,thus providing novel insights into how to manage artificial microbial systems for the wide application of the bioindustry.

关键词： community structure mathematical model metabolic division of labor substrate synthetic microbial consortium

No evidence for a genetic association between female mating preference and male secondary sexual trait in a Lake Victoria cichlid fish

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Current Zoology 2010年第1期56卷 57-64页

作者： Inke van der SLUIJS Ole SEEHAUSEN Tom J.M.Van DOOREN Jacques J.M.van ALPHEN Department of Animal Ecology Institute of Biology Leiden University Department of Biology McGill University Institute of Ecology and Evolution University of Bern Department of Fish Ecology & Evolution Centre of Ecology Eawag Swiss Federal Institute for Aquatic Science and TechnologyEvolution & Biogeochemistry

Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in therapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or accelerated by genetic associations betweenfemale preference loci and male coloration loci. Preferences, as well as coloration, are heritable traits and are probably determinedby more than one gene. However, little is known about potential genetic associations between these traits. In turbid water,we found a population that is variable in male nuptial coloration from blue to yellow to red. Males at the extreme ends of thephenotype distribution resemble a reproductively isolated species pair in clear water that has diverged into one species withblue-grey males and one species with bright red males. Females of the turbid water population vary in mating preference coincidingwith the male phenotype distribution. For the current study, these females were mated to blue males. We measured the colorationof the sires and male offspring. Parents-offspring regression showed that the sires did not affect male offspring coloration,which confirms earlier findings that the blue species breeds true. In contrast, male offspring coloration was determined by theidentity of the dams, which suggests that there is heritable variation in male color genes between females. However, we found thatmating preferences of the dams were not correlated with male offspring coloration. Thus, there is no evidence for strong geneticlinkage between mating preference and the preferred trait in this

关键词：维多利亚湖遗传相关鲷科鱼类证据性状男性偏好交配

Microbiological denitrification and inhibition of intermediates in lake waters

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Chinese Science Bulletin 1999年第S2期44卷 126-128页

作者： M.Snozzi Swiss Federal Institute of Environmental Science and Technology (eawag) Zurich CH-8600 Switzerland

NITKOGEIV cycle is disturbed by human activities, while some nitrogenous compounds are harmful to hu- man health. When large amounts of nitrogenous compounds such as protein, urea, etc., which can bedegraded to NH4+ by microbes, enter waters, some of them are assimilated to biomass, but most are stillin waters. In the presence of oxygen, NH4+ are oxidized to NC2- and NO3- by autotrophic bacteria. Inanoxic phase, denitrifiers such as Pseudomonas Migula, Achromobacteaceae, Bacillus and Micrococcus,etc. will proceed denitrification, utilizing N03- as the terminal electron acceptor instead of O2 in the respiratory chain. Because bacteria denitrification, involving four steps from NO3- to NO2-, NO, N2O andN2, in fact, is an enzymatically catalytic process, changes of environmental factors such as

关键词： microbiological denitrification inhibition of intermediates lake waters.

Environmental Sustainability of Water Footprint in China' Mainland

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Geography and Sustainability 2020年第1期1卷 8-17页

作者： Junguo Liu Dandan Zhao Ganquan Mao Wenhui Cui He Chena Hong Yang School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Water&Development Research Group Department of Built EnvironmentAalto UniversityPO Box 15200Espoo 00076Finland Department of Systems Analysis Integrated Assessment and ModellingSwiss Federal Institute for Aquatic Science and Technology(Eawag)Dübendorf 8600Switzerland

Water footprint(WF)measures human appropriation of water resources for consumptive use of surface and ground water(blue WF)and soil water(green WF)and for assimilating polluted water(grey WF).Questions have been often asked about the exact meaning behind the numbers from WF accounting.However,to date environmental sustainability of WF has never been assessed at the sub-national level over time.This study evaluated the environmental sustainability of blue,green and grey WF for China’s 31 mainland provinces in 2002,2007 and 2012,and identified the unsustainable hotspots.Overall,the total WF increased by 30%between 2002 and 2012.The growth can be attributed to the increase of grey WF because the green and blue WF showed only a slight rise.Among all provinces investigated in 2012,eleven showed unsustainable blue WF(sustainability index SI<0),which were mainly located in the North China Plain.There were 12 provinces that displayed unsustainable green WF,and they were distributed in China’s southern and southeastern areas.The grey WF was not sustainable in approximately two third of provinces(19),which were mainly located in China’s middle and northern regions and Guangdong province.More than half of China’s provinces showed trends of improved SI of green and blue WF from 2002 to 2012.However,the SI of grey WF decreased in almost two third of provinces.Poor levels of WF sustainability were due to water scarcity and pollution,which intensify the degradation of local rivers and ecosystems and make restoration more difficult.The results shed light on the policy making needed to improve sustainable water management,and ecological restoration of hotspot regions.

关键词： Green water Blue water Grey water Sustainable development Ecological restoration

微型浮游生物应为湖泊中的方解石沉淀负责吗?

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AMBIO－人类环境杂志 2004年第B12期33卷 535-540页

作者： Maria Dittrich Martin Obst 张国梁（译）盖峥（校） eawag的瑞士联邦环境科学拜鲁特大学不详

湖泊中方解石的沉积是环境变迁的重要记录。为了解译这些档案,有必要了解方解石的起源。普遍认为方解石的沉淀能被细菌和藻类所诱导。然而,详细的机制仍不清楚。本综述概括了已知的在方解石沉淀和自养微型浮游生物之间的相互作用。我们... 详细信息

湖泊中方解石的沉积是环境变迁的重要记录。为了解译这些档案,有必要了解方解石的起源。普遍认为方解石的沉淀能被细菌和藻类所诱导。然而,详细的机制仍不清楚。本综述概括了已知的在方解石沉淀和自养微型浮游生物之间的相互作用。我们考虑了来自野外和实验室研究两方面的发现。野外研究显示,在贫营养湖中方解石的沉淀与微型蓝细菌的繁盛有密切的关系。室内实验使微藻类诱导沉淀的机制清晰化了。实验也显示由微型蓝细菌诱导的沉淀受到各种不同因素的影响,包括无机碳的吸收和细胞壁结构。最近的研究指出还必须考虑环境条件如湖水组成的影响。我们得出结论,需要原位观察受控条件下在微型浮游生物细胞上的沉淀过程以改善我们对矿物细菌相互作用的理解。

关键词：微型浮游生物沉淀过程方解石湖泊实验室研究环境变迁相互作用野外研究细胞壁结构