Discrimination of Soils and Assessment of Soil Fertility Using Information from an Ion Selective Electrodes Array and Artificial Neural Networks          下载免费PDF全文

Aitor Mimendia  Juan M. Gutiérrez  Josep M. Alcañiz  Manel del Valle 《洁净——土壤、空气、水》2014,42(12):1808-1815

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A Comparison of Different Indirect Techniques to Evaluate Volcanic Intact Rock Strength     

Rodrigo del Potro  Marcel Hürlimann 《Rock Mechanics and Rock Engineering》2009,42(6):931-938

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UV transit observations of EUV-heated expanded thermospheres of Earth-like exoplanets around M-stars: testing atmosphere evolution scenarios     

H. Lammer  V. Eybl  K. G. Kislyakova  J. Weingrill  M. Holmstr?m  M. L. Khodachenko  Yu. N. Kulikov  A. Reiners  M. Leitzinger  P. Odert  M. Xiang?Gr��?  B. Dorner  M. G��del  A. Hanslmeier 《Astrophysics and Space Science》2011,335(1):39-50

The detection and investigation of EUV heated, extended and non-hydrostatic upper atmospheres around terrestrial exoplanets would provide important insights into the interaction of the host stars plasma environment as well as the evolution of Earth-type planets their atmospheres and possible magnetic environments. We discuss different scenarios where one can expect that Earth-like planets should experience non-hydrostatic upper atmosphere conditions so that dynamically outward flowing neutral atoms can interact with the stellar plasma flow so that huge hydrogen coronae and energetic neutral atoms (ENA) can be produced via charge exchange. By observing the size of the extended upper atmospheres and related ENA-clouds and by determining the velocities of the surrounding hydrogen atoms, conclusions can be drawn in respect to the origin of these features. Due to the large number of M-type stars in our neighbourhood and their long periods of strong and moderate stellar activity in comparison to G-stars, we expect that M-type stars represent the most promising candidates for the detection of hydrogen ENA-clouds and the subsequent study of the interaction between the host star and the planets?? upper atmosphere. We show that the low mass of M-type stars also makes them preferable targets to observe extended hydrogen clouds around terrestrial exoplanets with a mass as low as one Earth mass. Transit follow-up observations in the UV-range of terrestrial exoplanets around M-type stars with space observatories such as the World Space Observatory-UV (WSO-UV) would provide a unique opportunity to shed more light on the early evolution of Earth-like planets, including those of our own Solar System.  相似文献   

The Water Vapour Continuum: Brief History and Recent Developments     

Keith P. Shine  Igor V. Ptashnik  Gaby R?del 《Surveys in Geophysics》2012,33(3-4):535-555

The water vapour continuum is characterised by absorption that varies smoothly with wavelength, from the visible to the microwave. It is present within the rotational and vibrational–rotational bands of water vapour, which consist of large numbers of narrow spectral lines, and in the many ‘windows’ between these bands. The continuum absorption in the window regions is of particular importance for the Earth’s radiation budget and for remote-sensing techniques that exploit these windows. Historically, most attention has focused on the 8–12?μm (mid-infrared) atmospheric window, where the continuum is relatively well-characterised, but there have been many fewer measurements within bands and in other window regions. In addition, the causes of the continuum remain a subject of controversy. This paper provides a brief historical overview of the development of understanding of the continuum and then reviews recent developments, with a focus on the near-infrared spectral region. Recent laboratory measurements in near-infrared windows, which reveal absorption typically an order of magnitude stronger than in widely used continuum models, are shown to have important consequences for remote-sensing techniques that use these windows for retrieving cloud properties.  相似文献   

A multi-scale hierarchical framework for developing understanding of river behaviour to support river management     

A. M. Gurnell  M. Rinaldi  B. Belletti  S. Bizzi  B. Blamauer  G. Braca  A. D. Buijse  M. Bussettini  B. Camenen  F. Comiti  L. Demarchi  D. García de Jalón  M. González del Tánago  R. C. Grabowski  I. D. M. Gunn  H. Habersack  D. Hendriks  A. J. Henshaw  M. Klösch  B. Lastoria  A. Latapie  P. Marcinkowski  V. Martínez-Fernández  E. Mosselman  J. O. Mountford  L. Nardi  T. Okruszko  M. T. O’Hare  M. Palma  C. Percopo  N. Surian  W. van de Bund  C. Weissteiner  L. Ziliani 《Aquatic Sciences - Research Across Boundaries》2016,78(1):1-16

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Classification of river morphology and hydrology to support management and restoration     

M. Rinaldi  A. M. Gurnell  M. González del Tánago  M. Bussettini  D. Hendriks 《Aquatic Sciences - Research Across Boundaries》2016,78(1):17-33

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Middle Eocene‐Oligocene broken‐foreland evolution in the Andean Calchaqui Valley,NW Argentina: insights from stratigraphic,structural and provenance studies     

C. del Papa  F. Hongn  J. Powell  P. Payrola  M. Do Campo  M. R. Strecker  I. Petrinovic  A. K. Schmitt  R. Pereyra 《Basin Research》2013,25(5):574-593

Two end‐member models have been proposed for the Paleogene Andean foreland: a simple W‐E migrating foreland model and a broken‐foreland model. We present new stratigraphic, sedimentological and structural data from the Paleogene Quebrada de los Colorados (QLC) Formation, in the Eastern Cordillera, with which to test these two different models. Basin‐wide unconformities, growthstrata and changes in provenance indicate deposition of the QLC Formation in a tectonically active basin. Both west‐ and east‐vergent structures, rooted in the basement, controlled the deposition and distribution of the QLC Formation from the Middle Eocene to the Early Miocene. The provenance analysis indicates that the main source areas were basement blocks, like the Paleozoic Oire Eruptive Complex, uplifted during Paleogene shortening, and that delimits the eastern boundary of the present‐day intraorogenic Puna plateau. A comparison of the QLC sedimentary basin‐fill pattern with those of adjacent Paleogene basins in the Puna plateau and in the Santa Bárbara System highlights the presence of discrete depozones. These reflect the early compartmentalization of the foreland, rather than a stepwise advance of the deformation front of a thrust belt. The early Tertiary foreland of the southern central Andes is represented by a ca. 250‐km‐wide area comprising several deformation zones (Arizaro, Macón, Copalayo and Calchaquí) in which doubly vergent or asymmetric structures, rooted in the basement, were generated. Hence, classical foreland model is difficult to apply in this Paleogene basin; and our data and interpretation agree with a broken‐foreland model.  相似文献   

Carbon isotope systematics of the Cambrian–Vendian aquifer system in the northern Baltic Basin: Implications to the age and evolution of groundwater     

Valle Raidla  Kalle Kirsimäe  Rein Vaikmäe  Enn Kaup  Tõnu Martma 《Applied Geochemistry》2012

Groundwater in the Cambrian–Vendian aquifer system has a strongly depleted stable isotope composition (δ¹⁸O values of about −22‰) and a low radiocarbon concentration, which suggests that the water is of glacial origin from the last Ice Age. The aim of this paper was to elucidate the timing of infiltration of glacial waters and to understand the geochemical evolution of this groundwater. The composition of the dissolved inorganic C (DIC) in Cambrian–Vendian groundwater is influenced by complex reactions and isotope exchange processes between water, organic materials and rock matrix. The δ¹³C composition of dissolved inorganic C in Cambrian–Vendian water also indicates a bacterial modification of the isotope system. The corrected radiocarbon ages of groundwater are between 14,000 and 27,000 radiocarbon years, which is coeval with the advance of the Weichselian Glacier in the area.  相似文献   

Groundwater flow model, recharge estimation and sustainability in an arid region of Patagonia, Argentina   总被引：2，自引：2，他引：0  

María del Pilar Alvarez  María Marta Trovatto  Mario Alberto Hernández  Nilda González 《Environmental Earth Sciences》2012,66(7):2097-2108

The Península Valdés, in northeastern Patagonia, Argentina, is characterised by its arid climate and the lack of perennial watercourses; thus, all economic activities depend on the groundwater resources. Water demand is mainly associated with tourism, which is centralised in Puerto Pirámides and supplied by a water desalination plant, and to sheep farming, supplied by the local aquifer. Due to the exponential growth of tourism, the government is planning to exploit groundwater and convey it by aqueduct to the abovementioned locality. The objectives of this study were to corroborate the conceptual geohydrological model, to develop a mathematical model to simulate the response of the aquifer to different scenarios, and to assess the incidence of water input into the system as a variable—a function that poses difficulties in the models for arid regions. The Visual Modflow 4.1 code was used, calibrating it in trial-and-error mode, changing the recharge and hydraulic conductivity parameters with different variants in the recharge zone and in the inclusion or exclusion of the evapotranspiration module. Results indicate the importance of the recharge analysis by treating rainfall at daily time steps. The adjusted model was exposed to four scenarios with variations in water input and in output by pumping. It can be concluded that under different input conditions, but with a controlled extraction, the system responds in a sustainable manner.  相似文献   

Two hundred years of environmental change in Picos de Europa National Park inferred from sediments of Lago Enol, northern Iberia     

Lourdes L��pez-Merino  Ana Moreno  Manel Leira  Javier Sigr��  Pen��lope Gonz��lez-Samp��riz  Blas L. Valero-Garc��s  Jos�� Antonio L��pez-S��ez  Manola Brunet  Enric Aguilar 《Journal of Paleolimnology》2011,46(3):453-467

We present a study of two short sediment cores recovered from Lago Enol, in the Picos de Europa National Park, Cantabrian Mountains, northern Iberia. We inferred past climate conditions and anthropogenic impacts using geochemical and biological (pollen and diatoms) variables in the dated sequences, in conjunction with temperature and precipitation data collected since 1871 at meteorological stations in the region. The record provides evidence of environmental changes during the last 200 years. At the end of the Little Ice Age (~1800?C1875 AD) the region was characterized by an open landscape. Long-term use of the area for mixed livestock grazing in the mountains, and cultivation of rye during the nineteenth century, contributed to the expansion of grassland at the expense of forest. Warmer temperatures since the end of the nineteenth century are inferred from a change in diatom assemblages and development of the local forest. Socioeconomic transformation during the twentieth century, such as livestock changes related to dairy specialization, planting of non-native trees, mining activities, and management of the national park since its creation in 1918, caused profound changes in the catchment and in the lake ecology. The last several decades (~1970?C2007 AD) of the Lago Enol sediment record are strikingly different from previous periods, indicating lower runoff and increasing lake productivity, particularly since AD 2000. Today, the large number of tourists who visit the area cause substantial impacts on this ecosystem.  相似文献