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Jacek A. Majorowicz 《Pure and Applied Geophysics》1996,147(1):1-24
The results of precision temperature logs made to depths of several hundred meters in some 80 wells in Western Canada, most of which are located in the Prairie Provinces, show evidence of warming at the ground surface in the 0.5 K to 3.5 K range (average=2.2±0.7 K, for 80 unevenly distributed sites). Modeling shows that this warming mostly pertains to this century and it has been most substantal in the last four decades if the ramp function of the linear increase of surface temperature is assumed. Using the step function model's increase of surface temperature (land clearing, forest fires, etc.) the calculated onset of warming would pertain mostly to the last two decades. Contour maps of ground temperatures currently and previously and a contour map of the ground warming magnitude dilineate a large regional character of the ground temperature change at the southern marigin of permafrost for the large area of the Prairie Provinces. In many cases however, the magnitude of ground warming is much larger than the magnitude of air warming. This is especially evident for the northern areas of Alberta in the boreal forest ecoprovince. The magnitude of ground warming is equal to the magnitude of surface air warming in southern Alberta in the grassland and aspen parkland ecoprovinces. The analysis of the temperature depth response to the surface warming from well data shows the integrated effect of surface air warming together with the increases in ground temperature due to natural terrain effects and other anthropogenical changes to the surface of the earth. 相似文献
3.
Milena B. Fernandes Marie-Alexandrine Sicre Anne Boireau Jacek Tronczynski 《Estuaries and Coasts》1997,20(2):281-290
Dissolved and particulate hydrocarbons of biogenic origin were investigated for the first time in surface waters along the Seine River and its estuary. They comprise n-alkanes (n-ALKs) and diagenetic polycyclic aromatic hydrocarbons (PAHs). Samples were collected in three different sections of the estuary: the riverine zone, the mixing zone, and the marine zone. At the river mouth, two mooring stations were used for the collection of samples over tidal cycles. Total particulate n-ALK concentrations ranged from 31 ng 1?1 to 2,918 ng 1?1, or 5 μg g?1 dry ng 1?1, or 2 μg g?1 of SM. Concentrations varied with the SM load and could be related to sedimentation and estuarine mixing. The sources of the n-ALKs were different in each zone of the estuary. The dissolved n-ALKs displayed lower concentrations than the particulate phase, varying from 136 ng 1?1 to 344 ng 1?1, while biogenic dissolved PAHs were almost absent. 相似文献
4.
A reconstruction of the palaeohydrological conditions of a flood‐plain: a multi‐proxy study from the Grabia River valley mire,central Poland 下载免费PDF全文
Dominik Pawłowski Grzegorz Kowalewski Krystyna Milecka Mateusz Płóciennik Michał Woszczyk Tomasz Zieliński Daniel Okupny Wojciech Włodarski Jacek Forysiak 《Boreas: An International Journal of Quaternary Research》2015,44(3):543-562
This study investigated the Grabia River valley mire in central Poland to reconstruct its palaeoenvironmental conditions from the Younger Dryas to the present. We analysed sedimentological, biological and geochemical data from the palaeo‐oxbow lake and valley mire to identify the principal hydrological trends, especially episodes of high water level. During the Lateglacial and Holocene, the Grabia River had a meandering channel, and its hydraulic parameters and the channel dimensions changed in response to climatic oscillations and vegetation development. We identified phases of high flood intensity and high groundwater level that correlate with regional and supraregional climatic events. The frequency and timing of palaeohydroclimatic oscillations show strong similarities to records from other sites in Poland and the rest of Europe. We show that various analytical methods, namely, pollen, plant macrofossils, Cladocera, Chironomidae, sedimentological, geochemical and radiocarbon data, can be effective tools for reconstructing past hydroclimatic changes in palaeo‐oxbow lakes and investigating the effects of past climate changes on river environments. The high sensitivity of the biota, especially Cladocera, to changes in water level permits the reconstruction of palaeoecological changes, especially flood episodes that occurred in the river valley. In particular, the increase in the proportion of sediment‐associated Cladocera and pelagic taxa was closely correlated with floods. Through comparisons with the palaeobiological data, geochemical data allowed the identification of humid phases within the fen associated with a rising groundwater table, direct fluvial activity (floods) and alluvial deposition. We also discuss the limitations of palaeohydrological reconstructions based on these proxies, especially on fossil aquatic invertebrates. 相似文献
5.
Ćwiek Mateusz Matusiak-Małek Magdalena Puziewicz Jacek Ntaflos Theodoros 《International Journal of Earth Sciences》2018,107(5):1731-1753
International Journal of Earth Sciences - The Oligocene/Miocene basanite from Pilchowice (Sudetes Mts., SW Poland) carries numerous small xenoliths of mantle peridotite, mostly harzburgite. The... 相似文献
6.
Qianqi Zhang Jacek Szwedo Daran Zheng Bo Wang Haichun Zhang 《Proceedings of the Geologists' Association. Geologists' Association》2021,132(2):199-206
A planthopper originally assigned to the genus Boreocixius in Surijokocixiidae (Surijokocixioidea, Fulgoromorpha) from the Ladinian (Middle Triassic) of Tongchuan in Shaanxi, northwestern China is described as Boreocixius tongchuanensis Zhang et al. sp. nov. As the third species ascribed to the genus, it differs from its congeners in having the much larger tegmen with postnodal veinlets and pigmented bands, providing new morphological information for Boreocixius. The establishment of the new species further increases the diversity of Boreocixius and Surijokocixiidae as well. 相似文献
7.
8.
Mark S. T. Bukowinski Philip E. Wannamaker Manfred Koch Yukio Fujinawa Dr. Pradeep Talwani D. Möhlmann Andrew H. Knoll Lucia Lovison-Golob Krzysztof Haman Hanna Pawłowska Henryk Piwkowski Dr. Anthony Dore Nguyen Xuan Huy Edward R. Cook Jan Błecki Jacek Leliwa-Kopystynski Magdalena Sroczynska-Kozuchowska 《Pure and Applied Geophysics》1993,140(1):139-177
9.
Żaneta Polkowska Aleksander Astel Marzena Grynkiewicz Tadeusz Górecki Jacek Namieśnik 《Journal of Atmospheric Chemistry》2002,41(3):239-264
The paper presents monitoring results and environmental pollution assessment for the Gdask-Sopot-Gdynia Tricity (Poland), based onanalysis of precipitation. Precipitation samples were collected over a period of 12 months (January–December 1998) at ten locations in the Tricity. The following selected ions were determined in the samples:SO4
2–, F–, Cl–, NO3
–,PO4
3–, NH4
+, Na+,Mg2+, Ca2+, K+. The results were subjected to full statistical evaluation. Values of the parameters determined were correlated with each other. An attempt was made to explain co-occurrences of certain ions and the significance of their mutual effects. Pollutant concentrations and loads in precipitation were also correlated with data on wind direction and temperature in the region.Deposition of pollutants was very high in spring due to the prevailing air circulation patterns and low temperatures. Analysis of the correlations between co-occurring ions confirmed the significant impact of the location (sea coast) on the composition of rain water. Ionic ratios in rainwater were similar to those observed for sea salt samples. In addition, heavy traffic was most probably responsible for high concentrations of various forms of nitrogen and sulphates in the vicinity of major highways. 相似文献
10.
Ordered weighted averaging with fuzzy quantifiers: GIS-based multicriteria evaluation for land-use suitability analysis 总被引:9,自引:0,他引:9
Jacek Malczewski 《International Journal of Applied Earth Observation and Geoinformation》2006,8(4):270-277
The objective of this paper is to incorporate the concept of fuzzy (linguistic) quantifiers into the GIS-based land suitability analysis via ordered weighted averaging (OWA). OWA is a multicriteria evaluation procedure (or combination operator). The nature of the OWA procedure depends on some parameters, which can be specified by means of fuzzy (linguistic) quantifiers. By changing the parameters, OWA can generate a wide range of decision strategies or scenarios. The quantifier-guided OWA procedure is illustrated using land-use suitability analysis in a region of Mexico. 相似文献