Separating physical and physiological effects of temperature on zooplankton feeding rate     

Benjamin?Loiterton  Marcus?Sundbom  Tobias?VredeEmail author 《Aquatic Sciences - Research Across Boundaries》2004,66(1):123-129

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Halogenation processes linked to red wood ant nests (<Emphasis Type="Italic">Formica</Emphasis> spp.) and tectonics     

Gabriele M. Berberich  Tobias Sattler  Dietrich Klimetzek  Simon A. Benk  Martin B. Berberich  Daniela Polag  Heinz Friedrich Schöler  Elliot Atlas 《Journal of Atmospheric Chemistry》2017,74(2):261-281

We investigated and evaluated the occurrence of fault zone tracer gases (CO₂, He, Rn), volatile organohalogens (CH₃Cl, CHCl₃, CHBr₃), alkanes and limonene in soil and nest gases of red wood ants (RWA) in comparison to ambient air, in a seismically active area. In this new approach, we compared RWA-free areas to RWA-areas by combining different investigation and analytical methods. In soil gas, the fault zone tracer gas Rn was surprisingly highly correlated to limonene, suggesting a combination of biotic production of limonene and abiotic degassing of Rn in a seismically active area; moderate correlations were found with trihalomethanes and other halocarbons. In RWA nests a variety of elevated concentrations of haloforms were found, while remaining below the atmospheric background values in RWA-free areas. The evidence of CHCl₃ in RWA nests is the first record. Its average concentrations in nests of F. rufa and F. polyctena were up to 3 fold higher than atmospheric background and up to 28–70 fold higher compared to e.g. volcanic emissions being considered as one of its main geogenic sources. Thus, RWA nests could possibly be an additional source for CHCl₃ liberation. Consequently, apart from RWA being bioindicators for seismically active degassing faults, they might also be used as bioindicators for CHCl₃ formation in forest soils. Although we cannot yet differentiate between a geogenic/abiotic and a biotic formation. RWA nests will have to be reconsidered for halocarbon formation in future quantifications of geochemical cycles at global scale, since they impact organic soil chemistry through biotic and/or abiotic pathways. Therefore, further larger-scale research in different tectonic settings but also in well-known CHCl₃ “hot spot” study areas such as the Klosterhede area (Denmark) should focus directly on gas sampling from confirmed active fault systems. Nests of other ant species should be addressed to compare seasonal, diurnal and nocturnal variations of degassing procedures in relation to earth tides, different geologic settings, and tectonic events such as earthquakes and on quantifying the fluxes to the atmosphere.  相似文献   

Temporal Scales of the Nocturnal Flow Within and Above a Forest Canopy in Amazonia     

Daniel M. Santos  Otávio C. Acevedo  Marcelo Chamecki  José D. Fuentes  Tobias Gerken  Paul C. Stoy 《Boundary-Layer Meteorology》2016,161(1):73-98

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Six temperature and precipitation regimes of the contiguous United States between 1895 and 2010: a statistical inference study     

Samuel S. P. Shen  Olaf Wied  Alexander Weithmann  Tobias Regele  Barbara A. Bailey  Jay H. Lawrimore 《Theoretical and Applied Climatology》2016,125(1-2):197-211

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Transfer patterns in Phase I of the EU Emissions Trading System: a first reality check based on cluster analysis   总被引：1，自引：0，他引：1  

Regina A. Betz  Tobias S. Schmidt 《Climate Policy》2016,16(4):474-495

In 2005, the world's largest Emissions Trading System (ETS) was introduced in the EU. Economic theory assumes high efficiency of such market-based instruments since companies have the flexibility to trade allowances. However, to date there is a lack of understanding on how companies have participated in the allowance markets. This article uses data on transfers of allowances between 2005 and the end of 2007, published by the EU in the Community Independent Transaction Log (CITL) after a five-year delay. We use cluster analysis to detect patterns in the data and differentiate transfer behaviour. We find that the vast majority of participants (7212 accounts) are rather passive in terms of transfers. Of these, more than half are hardly participating in the market at all, whereas one-third are accounts managed by another account belonging to the parent company. Opposed to that, 143 accounts show more active, but relatively diverse transfer behaviour. We also identify differences in sectoral representations, account types, and primary allocation across the seven clusters. While the passive accounts mostly belong to installations regulated under the EU ETS, the most active accounts are classified as ‘non-regulated account type'.  相似文献   

3D modelling and sheath folding at the Falun pyritic Zn-Pb-Cu-(Au-Ag) sulphide deposit and implications for exploration in a 1.9 Ga ore district,Fennoscandian Shield,Sweden     

Tobias C. Kampmann  Michael B. Stephens  Pär Weihed 《Mineralium Deposita》2016,51(5):665-680

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School-based environmental education in the context of a research and development project on integrated water resources management: experiences from Mongolia     

Daniel Karthe  Tobias Reeh  Michael Walther  Steffen Niemann  Alexander Siegmund 《Environmental Earth Sciences》2016,75(18):1286

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Case study: characterization of source-separated blackwater and greywater in the ecological housing estate Lübeck “Flintenbreite” (Germany)     

Jan Christian Sievers  Tobias Wätzel  Jörg Londong  Eckhard Kraft 《Environmental Earth Sciences》2016,75(22):1428

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Properties of nonlinear dynamo waves     

S. M. Tobias 《地球物理与天体物理流体动力学》2013,107(1-4):287-343

Abstract

Dynamo theory offers the most promising explanation of the generation of the sun's magnetic cycle. Mean field electrodynamics has provided the platform for linear and nonlinear models of solar dynamos. However the nonlinearities included arc (necessarily) arbitrarily imposed in these models. This paper conducts a systematic survey of the role of nonlinearities in the dynamo process, by cousidering the behaviour of dynamo waves in the nonlinear regime. It is demonstrated that only by considering realistic nonlinearities that are non-local in space and time can modulation of the basic dynamo wave be achieved. Moreover this modulation is greatest when there is a large separation of timescales provided by including a low magnetic Prandtl number in the equation for the velocity perturbations.  相似文献   

Melt water driven stream and groundwater stage fluctuations on a glacier forefield (Dammagletscher,Switzerland)          下载免费PDF全文

Jan Magnusson  Florian Kobierska  Stephan Huxol  Masaki Hayashi  Tobias Jonas  James W. Kirchner 《水文研究》2014,28(3):823-836

In many mountain regions, large land areas with heterogeneous soils have become ice‐free with the ongoing glacier retreat. On these recently formed proglacial fields, the melt of the remaining glaciers typically drives pronounced diurnal stream level fluctuations that propagate into the riparian zone. This behaviour was measured on the Damma glacier forefield in central Switzerland with stage recorders in the stream and groundwater monitoring wells along four transects. In spite of the large groundwater stage variations, radon measurements in the near‐stream riparian zone indicate that there is little mixing between stream water and groundwater on daily time scales. At all four transects, including both losing and gaining reaches, the groundwater level fluctuations lagged the stream stage variations and were often damped with distance from the stream. Similar behaviours have been modelled using the diffusion equation in coastal regions influenced by tidal sea level variations. We thus tested the ability of such a model to predict groundwater level fluctuations in proglacial fields. The model reproduced several key features of the observed fluctuations at three of four locations, although discrepancies also arise due to non representative input data and model simplifications. Nevertheless, calibration of the model for the individual transects yielded realistic estimates of hydraulic diffusivities between the stream and groundwater monitoring wells. We conclude that studying diurnal groundwater fluctuations can provide important information about the subsurface hydrology of alpine watersheds dominated by glacier melt. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献