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1.
Arzu Çöltekin Rebecca Francelet Kai-Florian Richter John Thoresen Sara Irina Fabrikant 《制图学和地理信息科学》2018,45(4):339-353
We report on how visual realism might influence map-based route learning performance in a controlled laboratory experiment with 104 male participants in a competitive context. Using animations of a dot moving through routes of interest, we find that participants recall the routes more accurately with abstract road maps than with more realistic satellite maps. We also find that, irrespective of visual realism, participants with higher spatial abilities (high-spatial participants) are more accurate in memorizing map-based routes than participants with lower spatial abilities (low-spatial participants). On the other hand, added visual realism limits high-spatial participants in their route recall speed, while it seems not to influence the recall speed of low-spatial participants. Competition affects participants’ overall confidence positively, but does not affect their route recall performance neither in terms of accuracy nor speed. With this study, we provide further empirical evidence demonstrating that it is important to choose the appropriate map type considering task characteristics and spatial abilities. While satellite maps might be perceived as more fun to use, or visually more attractive than road maps, they also require more cognitive resources for many map-based tasks, which is true even for high-spatial users. 相似文献
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Renza Miorandi Andrea Borsato Silvia Frisia Ian J. Fairchild Detlev K. Richter 《水文研究》2010,24(21):3101-3114
Grotta di Ernesto is a cave site well suited for palaeoclimate studies because it contains annually laminated stalagmites and was monitored from 1995 to the end of 2008 for microclimate, hydrology and hydrochemistry. Long‐term monitoring highlighted that cave drips show three different hydrological responses to rainfall and infiltration: (1) fast seasonal drips in the upper part of the cave, which are mostly fed by fractures, (2) slow seasonal drips, located at mid‐depth in the cave characterized by mixed feeding and (3) slow drips, mostly located in the deeper gallery, which are fed by seepage flow from bulk porosity with a minor fracture‐fed component. The slow drips display daily cycles during spring thaw. Monitoring also indicated that drip waters are only slightly modified by degassing within the soil zone and aquifer and by prior calcite precipitation. Hydrochemical studies show a clear seasonality in calcite saturation index, which results in most cave calcite precipitation occurring during late autumn and winter with similar amounts of precipitated calcite on most stalagmites, regardless of drip rate (discharge) differences. Drip rate, and drip rate variability, therefore, has a minor role in modulating the amount of annual calcite formation. In contrast, drip rate, when associated with moderate reduction in calcite saturation index, clearly influences stalagmite morphology. Increasing drip rate yields a passage from candle‐, to cone‐ to dome‐shaped stalagmites. Very high drip rates feed speleothems with flowstone morphology. In summary, monitoring provides information about the karst aquifer and how hydrology influences those physical and chemical characteristics of speleothems which are commonly used as climate proxies. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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T.O. Richter H.C. de Stigter W. Boer C.C. Jesus T.C.E. van Weering 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(2):267-282
Submarine canyons represent natural conduits for preferential transport of particulate material, including anthropogenic contaminants, from coastal zones directly to the deep sea. To assess related dispersal of natural and anthropogenic lead (Pb), we analyzed Pb concentrations and stable isotope ratios in surface sediments and sediment trap particulate material from the Portuguese margin Nazaré and Setúbal/Lisbon canyons. Geochemical data are integrated with previously obtained data on near-bottom hydrodynamics and processes and pathways of sediment transport. The two canyon systems are located in close geographic proximity to each other, but represent contrasting settings in terms of sediment input and down-canyon sediment transport processes.Concentration–isotope diagrams and three-isotope plots (206Pb/207Pb vs. 208Pb/206Pb) suggest binary mixing between natural and anthropogenic end members. The inferred isotopic signature of pollutant Pb (206Pb/207Pb=1.143 [1.134–1.149, 95% confidence interval]) is most consistent with industrial Pb; ongoing influence from gasoline Pb additives is at most of minor importance. Two proposed natural end members most likely bracket the isotopic signature of natural Pb. Accordingly, binary mixing calculations indicate that on average 20–45% vs. 35–55% of total Pb is derived from anthropogenic sources in the Nazaré and Setúbal–Lisbon canyon systems, respectively. Enhanced anthropogenic influence in the latter area is consistent with its proximity to heavily populated and industrialized areas and with sediment input from the Tagus and Sado rivers, potential major carriers of pollutant particles. In both canyon systems, the anthropogenic component generally decreases with increasing water depth.Isotopic signatures of sediment trap particulate material are generally consistent with surface sediment data at similar water depth, but show large variability in the upper Nazaré canyon and major deviations from surface sediments in the lower canyon. In the lower canyon, Pb isotopic ratios of sediment trap particulate material mostly reflect low pelagic fluxes from the overlying water column, whereas surface sediment signatures are dominated by episodic down-canyon mass transport events. Such gravity flows appear to incorporate older (pre-industrial) material masking the isotopic signature of pollutant Pb. Large variability in the upper canyon reflects continuous sediment resuspension by bottom currents. Stronger average bottom currents are associated with higher 206Pb/207Pb ratios of sediment trap particulate material and hence decreased influence of pollutant Pb. This may reflect preferential resuspension of natural Pb at the canyon floor and/or additional remobilization of older, less-polluted sediment in adjacent areas such as the canyon walls. 相似文献
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Ekaykin A. A. Teben’kova N. A. Lipenkov V. Ya. Tchikhatchev K. B. Veres A. N. Richter A. 《Russian Meteorology and Hydrology》2020,45(2):132-140
Russian Meteorology and Hydrology - It is shown that the snow stake measurements in central Antarctica systematically underestimate the value of the snow build-up. Two methods for the calculation... 相似文献
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Hydrogen peroxide (H2O2) has been suggested as a possible oxidizer of the martian surface. Photochemical models predict a mean column density in the range of 1015-1016 cm−2. However, a stringent upper limit of the H2O2 abundance on Mars (9×1014 cm−2) was derived in February 2001 from ground-based infrared spectroscopy, at a time corresponding to a maximum water vapor abundance in the northern summer (30 pr. μm, Ls=112°). Here we report the detection of H2O2 on Mars in June 2003, and its mapping over the martian disk using the same technique, during the southern spring (Ls=206°) when the global water vapor abundance was ∼10 pr. μm. The spatial distribution of H2O2 shows a maximum in the morning around the sub-solar latitude. The mean H2O2 column density (6×1015 cm−2) is significantly greater than our previous upper limit, pointing to seasonal variations. Our new result is globally consistent with the predictions of photochemical models, and also with submillimeter ground-based measurements obtained in September 2003 (Ls=254°), averaged over the martian disk (Clancy et al., 2004, Icarus 168, 116-121). 相似文献
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