Clues on the Hubble sequence formation from self-consistent hydrodynamical simulations     

R. DomÍnguez-Tenreiro  A. Serna  A. Sáiz  M.M. Sierra-Glez. de Buitrago 《Astrophysics and Space Science》2003,284(2):397-400

We report on two fully self-consistent hydrodynamical simulations run, in the context of a ΛCDM cosmological model, with the DEVA code. Galaxy-like-objects of different morphologies form. The assembly patterns identified in these simulations give support to the ab initio scenario to explain morphological differentiation, even if violent events at lower z could also have played a role. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Fighting for a future: an actor-oriented planning approach to landscape preservation in Galicia     

Paul Swagemakers  Damian Copena Rodríguez  María Dolores Domínguez García  Xavier Simón Fernández 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):109-118

Modification and channelization of streams and rivers have been conducted extensively throughout the world during the past century. Subsequently, much effort has been directed at re-creating the lost habitats and thereby improving living conditions for aquatic organisms. However, as restoration methods are plentiful, it is difficult to determine which one to use to get the anticipated result. The aim of this study was to compare two commonly used methods in small Danish streams to improve the physical condition: re-meandering and passive restoration through cease of maintenance. Our investigation included measurement of the physical conditions in 29 stream reaches covering four different groups: (1) re-meandered streams, (2) LDC streams (the least disturbed streams available), (3) passively restored streams (>10?years stop of maintenance) and (4) channelized and non-restored streams. The in-stream habitats were compared through analysis of the measured physical parameters and by applying a habitat model. We found that re-meandering is a more effective way of re-creating near-natural physical conditions in small streams compared to passive restoration. This is probably due to the limited energy in small streams which restricts re-shaping of the stream channel. However, based on habitat suitability modelling, the change to the physical condition did not translate into improved habitat suitability for young of the year brown trout highlighting the value of using several methods when evaluating restoration success.  相似文献   

Nonlinear Force-Free Extrapolation of Emerging Flux with a Global Twist and Serpentine Fine Structures     

G. Valori  L. M. Green  P. Démoulin  S. Vargas Domínguez  L. van Driel-Gesztelyi  A. Wallace  D. Baker  M. Fuhrmann 《Solar physics》2012,278(1):73-97

We study the flux emergence process in NOAA active region 11024, between 29 June and 7 July 2009, by means of multi-wavelength observations and nonlinear force-free extrapolation. The main aim is to extend previous investigations by combining, as much as possible, high spatial resolution observations to test our present understanding of small-scale (undulatory) flux emergence, whilst putting these small-scale events in the context of the global evolution of the active region. The combination of these techniques allows us to follow the whole process, from the first appearance of the bipolar axial field on the east limb, until the buoyancy instability could set in and raise the main body of the twisted flux tube through the photosphere, forming magnetic tongues and signatures of serpentine field, until the simplification of the magnetic structure into a main bipole by the time the active region reaches the west limb. At the crucial time of the main emergence phase high spatial resolution spectropolarimetric measurements of the photospheric field are employed to reconstruct the three-dimensional structure of the nonlinear force-free coronal field, which is then used to test the current understanding of flux emergence processes. In particular, knowledge of the coronal connectivity confirms the identity of the magnetic tongues as seen in their photospheric signatures, and it exemplifies how the twisted flux, which is emerging on small scales in the form of a sea-serpent, is subsequently rearranged by reconnection into the large-scale field of the active region. In this way, the multi-wavelength observations combined with a nonlinear force-free extrapolation provide a coherent picture of the emergence process of small-scale magnetic bipoles, which subsequently reconnect to form a large-scale structure in the corona.  相似文献   

Trend of annual temperature and frequency of extreme events in the MATOPIBA region of Brazil     

Salvador  Mozar de A.  de Brito  J. I. B. 《Theoretical and Applied Climatology》2018,133(1-2):253-261

Theoretical and Applied Climatology - During the 1980s, a new agricultural frontier arouse in Brazil, which occupied part of the states of Maranhão, Tocantins, Piauí, and Bahia....  相似文献   

Distribution patterns and environmental correlates of Thaumarchaeota abundance in six deep subalpine lakes     

Cristiana Callieri  Salvador Hernández-Avilés  Michaela M. Salcher  Diego Fontaneto  Roberto Bertoni 《Aquatic Sciences - Research Across Boundaries》2016,78(2):215-225

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Assessment of exotic fish impacts on water quality and zooplankton in a degraded semi-arid floodplain wetland   总被引：1，自引：0，他引：1  

David G. Angeler  Miguel Álvarez-Cobelas  Salvador Sánchez-Carrillo  Maria A. Rodrigo 《Aquatic Sciences - Research Across Boundaries》2002,64(1):76-86

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Self-Organised Criticality and the Response of Wildland Fires to Climate Change     

Salvador Pueyo 《Climatic change》2007,82(1-2):131-161

Here I present a new approach to forecasting the effects of climate change on catastrophic events, based on the ‘self-organised criticality’ concept from statistical physics. In particular, I develop the ‘self-organised critical fuel succession model’ (SOCFUS), which deals with wildland fires. I show that there is good agreement between model and data for the response pattern of the whole fire size statistical distribution to weather fluctuations in a boreal forest region. I tentatively predict the fire regime in this region for an instance of possible climate change scenario. I show that the immediate response is sharper than usually thought, but part of the added burning rate might not persist indefinitely. A large fraction of the extra burning in the transition period is likely to be concentrated in a few ‘climate change fires’, much larger than the largest fires that could currently occur. I also suggest that the major fire events recently observed in some tropical rainforest regions belong to a qualitatively different, even more abrupt type of response, which is also predicted by the model. Electronic supplementary material Electronic supplementary material is available for this article at  相似文献   

Temperature as a tracer of hydrological dynamics in an anchialine cave system with a submarine spring     

Domínguez-Villar  David  Cukrov  Neven  Krklec  Kristina 《Hydrogeology Journal》2018,26(4):1249-1262

Hydrogeology Journal - Although temperature is a nonconservative tracer, it often provides useful information to understand hydrological processes. This study explores the potential of temperature...  相似文献   

Time is of the essence: adaptation of tourism demand to climate change in Europe     

Salvador Barrios  J. Nicolas Ibañez 《Climatic change》2015,132(4):645-660

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Multi‐phase evolution of gnammas (weathering pits) in a Holocene deglacial granite landscape,Minnesota (USA)     

David Domínguez‐Villar  Carrie E. Jennings 《地球表面变化过程与地形》2008,33(2):165-177

The morphometry of 85 gnammas (weathering pits) from Big Stone County in western Minnesota allows the assessment of the relative ages of the gnamma population. The ratio between maximum and minimum depths is independent of the initial size of the cavity and only depends on the weathering evolution. Therefore, the distribution of depth ratios can be used to assess the gnamma population age and the history of weathering. The asymmetrical distribution of depth ratios measured in Big Stone County forms three distinct populations. When these sets are analyzed independently, the correlation (r²) between maximum and minimum depths is greater than 0·95. Each single population has a normal distribution of depth ratios and the average depth ratios (δ‐value) for each population are δ₁ = 1·60 ± 0·05, δ₂ = 2·09 ± 0·04 and δ₃ = 2·42 ± 0·08. The initiation of gnamma formation followed the exhumation of the granite in the region. This granite was till and saprolite covered upon retreat of the ice from the Last Glacial Maximum. Nearby outcrops are striated, but the study site remained buried until it was exhumed by paleofloods issuing from a proglacial lake. These Holocene‐aged gnammas in western Minnesota were compared with gnammas of other ages from around the world. Our new results are in accordance with the hypothesis that δ‐values represent the evolution of gnammas with time under temperate‐ to cold‐climate dynamics. Phases of the formation of new gnammas may result from changes in weathering processes related to climate changes. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献