Combining airborne laser scanning and Landsat data for statistical modeling of soil carbon and tree biomass in Tanzanian Miombo woodlands     

Mikael Egberth  Gert Nyberg  Erik Næsset  Terje Gobakken  Ernest Mauya  Rogers Malimbwi  Josiah Katani  Nurudin Chamuya  George Bulenga  Håkan Olsson 《Carbon balance and management》2017,12(1):8

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Variable tolerance to Copper in two species from San Francisco bay     

Samuel N. Luoma  Daniel J. Cain  Kay Ho  Anne Hutchinson 《Marine environmental research》1983,10(4):209-222

In static toxicity experiments, tolerance to soluble Cu of the bivalve, Macoma balthica, and the copepod, Acartia clausi, varied substantially among populations sampled within San Francisco Bay. Intraspecific tolerance differed ten-fold or more for both species over relatively small distances, suggesting geographical isolation of populations is not a prerequisite for the development of intraspecific differences in tolerance by aquatic organisms.  相似文献   

Application of a mass-balance model to predict PCDD/F turnover in a Baltic coastal estuary     

O. Magnus Karlsson  J. Mikael Malmaeus  Sarah Josefsson  Karin Wiberg  Lars Håkanson 《Estuarine, Coastal and Shelf Science》2010

A dynamical, process-based mass-balance model was applied to quantify the transports of polychlorinated-p-dibenzodioxins and dibenzofurans (PCDD/Fs) to, within and from the Kallrigafjärden Bay, a coastal estuary in the Baltic Sea, and to predict the PCDD/F levels in the water and sediments of the bay. Before the modelling, a one-year sampling programme was implemented in 2007–2008 to measure the flows of PCDD/Fs in tributaries entering the system, the fluxes from the adjacent sea and the levels in water, sediment and fish within the estuary. The collected data set was used as input data to the model and for validation purposes.  相似文献   

Characteristic features of air ions at Mace Head on the west coast of Ireland     

Marko Vana  Mikael Ehn  Tuukka Petj  Henri Vuollekoski  Pasi Aalto  Gerrit de Leeuw  Darius Ceburnis  Colin D. O'Dowd  Markku Kulmala 《Atmospheric Research》2008,90(2-4):278-ICNAA07

Coastal nucleation events and behavior of cluster ions were characterized through the measurements of air ion mobility distributions at the Mace Head research station on the west coast of Ireland in 2006. We measured concentrations of cluster ions and charged aerosol particles in the size range of 0.34–40 nm. These measurements allow us to characterize freshly nucleated charged particles with diameters smaller than 3 nm. The analysis shows that bursts of intermediate ions (1.6–7 nm) are a frequent phenomenon in the marine coastal environment. Intermediate ion concentrations were generally close to zero, but during some nucleation episodes the concentrations increased to several hundreds per cm³. Nucleation events occurred during most of the measurement days. We classified all days into one of seven classes according to the occurrence and type of new particle formation. Nucleation events were observed during 207 days in 2006, most prominently in the spring and summer months. Rain-induced events, in turn, were observed during 132 days. Particle formation and growth events mostly coincided with the presence of low tide. Also small cluster ions (0.34–1.6 nm) were characterized. Average concentrations of small ions were 440 cm^− 3 for the negative ions and 423 cm^− 3 for the positive ions. Average mean mobilities of small ions were 1.86 cm²V^− 1s^− 1 and 1.49 cm²V^− 1s^− 1 for the negative and positive polarities, respectively. Concentrations of small ions were observed to be strongly dependent on the variations of meteorological parameters including wind speed and direction.  相似文献   

Modelling Fracture Propagation in Anisotropic Rock Mass     

Baotang Shen  Topias Siren  Mikael Rinne 《Rock Mechanics and Rock Engineering》2015,48(3):1067-1081

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Carbon capture and storage in developing countries: A comparison of Brazil, South Africa and India     

Mikael Román 《Global Environmental Change》2011,21(2):391-401

The ambition to introduce carbon capture and storage (CCS) technology in developing countries raises particular considerations and challenges, where, most fundamentally, pressing socio-economic needs imply that there are other political priorities than GHG mitigation. This suggests that the interest in, and viability of, large-scale deployment of CCS in developing countries has to be analyzed as a strategic issue in the overall context of national development. But what are then the strategic concerns that may influence developing countries’ decisions to pursue large-scale deployment of CCS technology? The present article takes a first step in answering this question by comparing CCS policies and ongoing activities in Brazil, India and South Africa.  相似文献   

A FEniCS-based programming framework for modeling turbulent flow by the Reynolds-averaged Navier-Stokes equations     

Mikael Mortensen  Hans Petter Langtangen  Garth N. Wells 《Advances in water resources》2011,34(9):1082-1101

Finding an appropriate turbulence model for a given flow case usually calls for extensive experimentation with both models and numerical solution methods. This work presents the design and implementation of a flexible, programmable software framework for assisting with numerical experiments in computational turbulence. The framework targets Reynolds-averaged Navier-Stokes models, discretized by finite element methods. The novel implementation makes use of Python and the FEniCS package, the combination of which leads to compact and reusable code, where model- and solver-specific code resemble closely the mathematical formulation of equations and algorithms. The presented ideas and programming techniques are also applicable to other fields that involve systems of nonlinear partial differential equations. We demonstrate the framework in two applications and investigate the impact of various linearizations on the convergence properties of nonlinear solvers for a Reynolds-averaged Navier-Stokes model.  相似文献   

Naturally and anthropogenically produced bromoform in the Kattegatt,a semi-enclosed oceanic basin     

Elisabet Fogelqvist  Mikael Krysell 《Journal of Atmospheric Chemistry》1991,13(4):315-324

The origin of bromoform in seawater and atmosphere, as well as possible sinks and breakdown mechanisms, is discussed. A bromoform budget is calculated for the Kattegatt area between Sweden and Denmark, where the input of bromoform from a power plant is significant. Both anthropogenically (250×10⁶ g yr^-1) and biogenically (350×10⁶ g yr^-1, 0.016 g m^-2 yr^-1) produced bromoform is likely to have a great impact locally on the inventory and the release to the atmosphere. Using measured surface concentrations of bromoform, the total annual release from the Kattegatt to the atmosphere is estimated to 550×10⁶ g (0.025 g m^-2 yr^-1).  相似文献   

Transneptunian Object Ephemeris Service (TNOEPH)     

Granvik  Mikael  Virtanen  Jenni  Muinonen  Karri  Bowell  Edward  Koehn  Bruce  Tancredi  Gonzalo 《Earth, Moon, and Planets》2003,92(1-4):73-78

We present a web service called TNOEPH ( http://asteroid.lowell.edu/)for ephemeris uncertainty prediction and dynamical classification ofshort-arc trans\-neptunian objects (TNOs). User-supplied observations are transformed to a rigorous sky-plane uncertainty map using the technique of statistical orbital ranging. We show examples of thegrowth of ephemeris uncertainty with time, and give the probabilities ofdifferent dynamical classifications for a few short-arc TNOs.  相似文献   

Variations of the Wake Height over the Bolund Escarpment Measured by a Scanning Lidar     

Julia Lange  Jakob Mann  Nikolas Angelou  Jacob Berg  Mikael Sjöholm  Torben Mikkelsen 《Boundary-Layer Meteorology》2016,159(1):147-159

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