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Horizontal Movement (horizontal + movement)
Selected AbstractsMeasurement of Horizontal and Vertical Movement of Ralstonia solanacearum in SoilJOURNAL OF PHYTOPATHOLOGY, Issue 10 2006M. Satou Abstract Two model systems were constructed to measure horizontal and vertical movement of bacteria in soil. These systems were applied to measuring movement of Ralstonia solanacearum (race 1, biovar 3), a causal agent of bacterial wilt of tomato, in andosol and sand at 28°C. The first system was used to measure horizontal movement of the bacteria in soil packed in a narrow horizontal frame. Suspension of the pathogen was applied to soil at one end of the frame, and bacterial number per gram of soil was measured over distance from the inoculation point after 4 days. Horizontal movement of R. solanacearum in supersaturated soil, but without flow, was possibly due to diffusion and the front advanced at 2.2 cm/day in andosol, and at 8.1 cm/day in sand. Using the same experimental system, but applying water inflow to one end of the frame only, the bacterium was detected at the front of water in andosol and sand. The front of the distribution advanced at 20.4 cm/h in andosol and 66.3 cm/h in sand. In the second experimental system, a cylinder of soil packed in a short tube was soaked with water, and soil at the top of the tube was inoculated with bacterial suspension. Immediately, soil cylinders were turned upward, and the bacterial number per gram of soil was measured along vertical distance from the inoculation point after 7 days. Using the system with andosol, the capillary water front rose to 32.5 cm over 7 days after inoculation, and R. solanacearum reached to 18.8 cm height. In sand, capillary water rose to 20.0 cm and the bacteria reached to 16.3 cm height. [source] Temporal-Spatial Structure of Intraplate Uplift in the Qinghai-Tibet PlateauACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2010Dewei LI Abstract: The intraplate uplift of the Qinghai-Tibet Plateau took place on the basis of breakup and assembly of the Precambrian supercontinent, and southward ocean-continent transition of the Proto-, Paleo-, Meso- and Neo-Tethys during the Caledonian, Indosinian, Yanshanian and Early Himalayan movements. The intraplate tectonic evolution of the Qinghai-Tibet Plateau underwent the early stage of intraplate orogeny characterized by migrational tectonic uplift, horizontal movement and geological processes during 180,7 Ma, and the late stage of isostatic mountain building characterized by pulsative rapid uplift, vertical movement and geographical processes since 3.6 Ma. The spatial-temporal evolution of the intraplate orogeny within the Qinghai-Tibet Plateau shows a regular transition from the northern part through the central part to the southern part during 180,120 Ma, 65,35 Ma, and 25,7 Ma respectively, with extensive intraplate faulting, folding, block movement, magmatism and metallogenesis. Simultaneous intraplate orogeny and basin formation resulted from crustal rheological stratification and basin-orogen coupling that was induced by lateral viscous flow in the lower crust. This continental dynamic process was controlled by lateral flow of hot and soft materials within the lower crust because of slab dehydration and melted mantle upwelling above the subducted plates during the southward Tethyan ocean-continent transition processes or asthenosphere diapirism. Intraplate orogeny and basin formation were irrelevant to plate collision. The Qinghai-Tibet Plateau as a whole was actually formed by the isostatic mountain building processes since 3.6 Ma that were characterized by crust-scale vertical movement, and integral rapid uplift of the plateau, accompanied by isostatic subsidence of peripheral basins and depressions, and great changes in topography and environment. A series of pulsative mountain building events, associated with gravity equilibrium and isostatic adjustment of crustal materials, at 3.6 Ma, 2.5 Ma, 1.8,1.2 Ma, 0.9,0.8 Ma and 0.15,0.12 Ma led to the formation of a composite orogenic belt by unifying the originally relatively independent Himalayas, Gangdisę, Tanghla, Longmenshan, Kunlun, Altyn Tagh, and Qilian mountains, and the formation of the complete Qinghai-Tibet Plateau with a unified mountain root after Miocene uplift of the plateau as a whole. [source] Modelling the behaviour of an embankment on soft clay with different constitutive modelsINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 10 2006M. Karstunen Abstract The paper investigates the effect of constitutive models on the predicted response of a simplified benchmark problem, an embankment on soft soil. The soft soil is assumed to have the properties of POKO clay from Finland and five different constitutive models are used to model the deposit. Two of the models are isotropic models, i.e. the Modified Cam Clay model and the Soft-Soil model. The other models are recently proposed constitutive models that account for plastic anisotropy. The S-CLAY1 and S-CLAY1S models are embedded in a standard elasto-plastic framework and account for anisotropy via a rotational hardening law. In addition, the S-CLAY1S model accounts for bonding and destructuration. In contrast, the Multilaminate Model for Clay (MMC) accounts for plastic anisotropy by utilizing so-called multilaminate framework. The results of numerical simulations show that accounting for anisotropy results in notable differences in the predicted settlements and horizontal movements compared to the predictions using the isotropic models. There are also significant differences in the K0 predictions by the different constitutive models and this has a significant impact on the results. Copyright Š 2006 John Wiley & Sons, Ltd. [source] Individual-based models of cod movement and population dynamicsJOURNAL OF FISH BIOLOGY, Issue 2003H. J. Edwards Many fish species undergo seasonal changes in distribution, as a result of horizontal migrations between feeding, nursery and spawning grounds. Exploring the processes involved in these movements may be the key to understanding interactions with other species, man and the environment, and is therefore crucial to effective fisheries management. Recent tagging experiments providing information on the distribution of migratory fish stocks have indicated pronounced regional and temporal differences in the migratory behaviour of cod, suggesting complex interactions between this commercially important fish species and the environment. This paper presents a model of the horizontal movements of demersal fish, principally cod, using an individual-based modelling approach to explore and predict the relationship between demersal fish movements and key environmental and ecological factors. The model simulates the basic biological processes of growth, movement and mortality, and is driven by the analysis of physical tagging data recorded by electronic data storage tags (DSTs). Results show that the incorporation of behavioural data from DSTs into spatially explicit individual-based models can provide realistic simulations of large-scale fish stocks, thus giving a better understanding of their basic ecology and allowing more effective management of commercially important fish species. Possibilities of future improvements and extensions to the model are discussed. [source] | ||||||||||