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41.
Total dissolved solids (TDS) in lake and catchment water is a result of geological structure, as well as duration of rock and water contact and human activity. In this paper, a potential dissolved solids (PtDS) in three ??czna–W?odawa Lake catchments was determined using extraction and computer software (GIS and AquaChem). Human pressure on water quality was estimated as a difference of the TDS and a catchment hydrogeochemical potential (TPtDS, total potential dissolved solids). TPtDS coefficient included hydrogeological features of the aquifer, soil cover impact on infiltrated water quality, and sediments susceptibility to denudation. The main advantage of the model is a possibility of its employment for every catchment or other areas (e.g. administrative) on both microscale and mesoscale. The highest TPtDS occurred in the catchment, favoured with underground supply, which was located in the vicinity of the Cretaceous mesoregional unit (Che?m Hills). The lowest value was observed in the catchment built with organogenic sediments and coarse material. A seasonal constancy of TPtDS values proved a stability of the lake‐catchment systems under study. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
42.
Dziak-Jankowska Beata Leliwa-Kopystyński Jacek Królikowska Mał Gorzata 《Earth, Moon, and Planets》2002,90(1-4):35-44
The aim of this modelling work is to assess shape changes of cometary nuclei caused by sublimation of ices. The simplest possible
model is assumed with the nucleus being initially spherical and its thermal conductivity being neglected. We have calculated
the time-dependent sublimation flux versus cometographic latitude. If the rotation axis of the comet is inclined to the orbital
plane, then sublimation leads to non-symmetrical changes of the nucleus shape. Calculations were performed for the nuclei
of comets Hale–Bopp and Wirtanen. 相似文献
43.
Dominik Pawłowski Beata Gruszka Hanna Gallas Joanna Petera-Zganiacz 《Journal of Paleolimnology》2013,49(4):679-696
Upper Saalian (Illinoian) glaciolacustrine deposits in central Poland, preserved in a tectonic graben, were exposed in an opencast lignite mine and investigated using sedimentological and micro-paleontological methods. The extraglacial lake sediments provide the first records of late Saalian cladoceran communities in central Europe, recovered from glaciolacustrine deposits. Sedimentation was dominated by a supply of clastics that fluctuated with the seasons, forming rhythmites. In addition to seasonal cyclicity, sedimentary and environmental conditions changed every several years to decades, with periods of increased inflow to the lake delivering sandy material, and periods of almost stagnant water dominated by suspension settling. The sediments contain Cladocera assemblages that indicate the lake was initially deep, oligotrophic, and filled with moderately cold water. Changes in Cladocera community composition and abundance were perhaps responses to climate seasonality. Zones without Cladocera were associated with seasons of higher inflow and sediment supply, and directly or indirectly, with tectonic activity in the graben. Earthquakes, documented by the presence of seismites, caused not only deformation of unconsolidated lake-bottom sediments, but possibly also changes in habitat characteristics. Combined sedimentological and biological data were used to infer the lake’s history and show that deposits of glaciolacustrine lakes can be used as indicators of past ecological and climate changes. 相似文献
44.
Parvin Farhana Ali Sk Ajim Calka Beata Bielecka Elzbieta Linh Nguyen Thi Thuy Pham Quoc Bao 《Theoretical and Applied Climatology》2022,149(1-2):639-659
Theoretical and Applied Climatology - Flood is considered as the most devastating natural hazards that cause the death of many lives worldwide. The present study aimed to predict flood... 相似文献
45.
Anna Swiatek Iwona Stanislawska Zbigniew Zbyszynski Beata Dziak-Jankowska 《Acta Geophysica》2014,62(1):259-269
Ionosphere coverage is likely to be a driver for the EGNOS coverage area. Hence, a study considering a dedicated ionosphere algorithm to improve the ionosphere coverage area has been conducted. The logic of the study is the following: the accuracy of the GPS signal depends mainly on the total electron content (TEC). At two close points, TEC changes in time in a very similar way; these are region dependent variables. This correlation decreases with growing distance between the observation points and is anisotropic. Based on TEC variogram analysis, the specific algorithm has been developed. This specific algorithm is presented and discussed. 相似文献