排序方式: 共有35条查询结果,搜索用时 15 毫秒
21.
Dana Procházková Libuše Ruprechtová Zdeňka Schenková Arnošt Dudek Reviewer J. Janský 《Studia Geophysica et Geodaetica》1977,21(3-4):293-295
Summary The method of treatment of the macroseismic data obtained on the territory of the CSSR after the main 1976 Friuli earthquake is described and the preliminary results are confronted with the geologic structure. 相似文献
22.
23.
Anetta?Drzeniecka-Osiadacz Justyna?KrynickaEmail author Ma?gorzata?Malkiewicz Kamilla?Klaczak Krzysztof?Miga?a 《Theoretical and Applied Climatology》2015,119(3-4):419-432
The aim of this article is to present statistical forecasting models concerning the dynamics of Artemisia pollen seasons in Wroc?aw, including the start and end, the date of maximum pollen concentration and seasonal pollen index (SPI). For statistical evaluation, use was made of aerobiological and meteorological data from the last 10 years (2002–2011). Based on this data, agroclimatic indicators, i.e. crop heat units (CHUs), were determined for various averaging periods. The beginning of the Artemisia pollen season in the studied time period, on average, took place on 23 June. Its length usually varied between 26 and 45 days, and maximum daily concentrations occurred between 31 July and 18 August. It was found that the beginning of the pollen season depends, above all, on the values of CHUs and photothermal unit (PTU) (p?<?0.05) in the period from March to June, for various thermal thresholds. The date of maximum daily concentration correlates with sunshine duration, PTU and air temperature for June and July (p?<?0.05). On the other hand, SPI is connected with thermal variables, i.e. average, maximum and minimum air temperatures and CHUs and heliothermal unit (HTU) for July (p?<?0.05) and the beginning of spring. Based on the correlation analysis and the chosen variables, regression models for the beginning date of Artemisia pollen season and SPI were prepared, which were then verified by using leave-one-out cross-validation. A better fit between modelled and actual values was found for the analysis concerning the season start date than for the SPI. 相似文献
24.
Abstract In this article we propose a careful analysis of the economic consequences of the Kyoto Protocol for Russia, taking into account the most recently available data and the latest developments in the trends regarding Russian economic recovery. We present a review of different GHG forecasts for Russia and develop a new forecast for uncertain GDP growth and changing elasticity of GHG emission per GDP. Since the rate of growth remains uncertain, elasticity could change over time, as well as the fuel mix. We apply the Monte-Carlo method to simulate these uncertainties and to produce a reasonable interval for CO2 emissions in 2010. The probability of Russia exceeding its Kyoto emissions budget is essentially zero. Further, we discuss the benefits for Russia from the Kyoto Protocol, and more generally from implementation of GHG mitigation policy. Ancillary benefits from Kyoto Protocol implementation will bring essential reductions in risk to human health. On the other hand, potential negative changes in the fuel mix and GDP structure, as well as a slowing of the innovation process, could exacerbate existing health problems. Alternatives to the Kyoto Protocol may bring much tougher commitments to Russia. We conclude that the Kyoto Protocol is the best possible deal for Russia. Therefore, Russia most will ratify it. 相似文献
25.
26.
As a result of socio-economic changes and land abandonment, the main ecological driver of the Carpathian landscape is the progression of the natural forest succession process. Thus, aspects of this process have become worthy of attention, especially in the context of carbon sequestration and the management of protected areas. Soil processes, especially within the topsoil, are some of the most susceptible to change, due to the accumulation of organic matter during such land-use transformations. The purposes of this study were to investigate the differences in topsoil development using the A Horizon Development Index (ADI) and to study the composition of humic substances and advanced organic matter humification in different land-use areas in selected Carpathian national parks, i.e. Bieszczady, Magura and Pieniny National Parks in southern Poland. Additionally, a goal of this study was to compare the ADI and the spectroscopic coefficients of humic substances as indicators of the degree of humus horizon shaping as well as advanced organic matter humification. In total, ten transects were selected, each consisting of three different land-use areas: semi-natural meadow, successional forest and old-growth forest. Soil colour was determined in fresh and air-dried samples using the Munsell colour chart. In air-dried soil samples pH, soil texture, total organic carbon and total nitrogen were measured. Humic substances were extracted and further characterized by UV-VIS spectroscopy. The ADI confirmed the influence of natural forest succession on soil colour darkening and the development of the uppermost soil layer. Spectroscopic analyses of humic substances showed two different patterns depending on soil depth. In the 0–10 cm layer, natural forest succession reduced the rate of the humification process and decreased the degree of maturity of fulvic acids; in the 10–20 cm layer, it led to an increase in the rate of the humification process and a decrease in the content of humic and fulvic acids at the beginning of the transformation. The comparison of two different indicators of soil development – the ADI and the spectroscopic coefficients of humic substances (Q4/6, Q2/4, Q2/3, Δ log K) – indicated that these indexes are based on different features of soil and cannot be used interchangeably. 相似文献
27.
28.
Sixty female flounder (Platichthys flesus) were collected in Autumn 2011, 15 from each of the following sampling sites: at the mouths of the Douro and Vistula Rivers, and at nearby open sea locations. The aim of the study was to assess several biomarkers in the two geographically distant regions. Hepatic EROD, GST, SOD, GPx, POx, LP; muscular AChE, BChE, LP; and branchial Na+/K+-ATPase were analysed. Moreover, BTI, PY, and three gross morphometric indices were calculated. The results were analysed with t-test, ANOVA, and PCA. Many differences were found between the open sea sites and the river mouths, mainly in Portugal, and between the two rivers. Salinity and pollution seem to be the main factors that affected the biomarkers. Effects of chronic pollution were observed at the river mouths, and an indication of a possible temporary exposure to pollutants was found at the open ocean site in Portugal. 相似文献
29.
Helena Alexanderson Ólafur Ingólfsson Andrew S. Murray Justyna Dudek 《Boreas: An International Journal of Quaternary Research》2013,42(3):532-543
The recent discovery of a subfossil polar bear (Ursus maritimus) jawbone in the Poolepynten coastal cliff sequence, western Svalbard, and its implications for the natural history of the polar bear motivated an effort to better constrain the environmental history and age envelope of the Poolepynten sediment sequence. The focus of the present study is on the lithostratigraphy of the coastal cliffs and on re‐dating the sequence using the Optically Stimulated Luminescence (OSL) dating technique. We report a revised lithostratigraphy and nine new OSL ages. It is concluded that the Poolepynten sequence contains evidence of four regional glaciation events, recorded in the strata as erosional unconformities or glacial deposits followed by shallow‐marine deposition signifying transgressions and subsequent glacio‐isostatic rebound and regression. Our OSL ages refine previous age determinations (14C and IRSL) and support the interpretation that the subfossil polar bear jawbone is probably of last interglacial (Eemian) age. 相似文献
30.
A one-dimensional mathematical model for heat and moisture flow in saturated porous materials is given. The model is formulated using capillary theory and depends upon the inter-relationship between pore radius, freezing point depression and the cryogenic suction. The conditions at the frost line include a criterion which determines whether heave and/or penetration of the frost line occurs.
Numerical results are given which were computed using an expanding—contracting finite-difference approximation. These results compare well with temperature and heave measurements made in the laboratory using a precise freezing cell. 相似文献