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31.
Agriculture is often not included in the baseline greenhouse gas (GHG) emission inventories created for local low carbon economy plans in Poland and other European countries. We therefore estimate the size of the carbon footprint from agricultural sources and indicate the share of agriculture in the total GHG emissions in selected Polish communes (LAU level 2). We propose a solution whereby local government units can estimate their carbon footprint independently and monitor the impact of actions taken to reduce emissions. The value of the carbon footprint from agriculture in the selected communes varies from .5 to 46.5 thousand Mg CO2eq/year, with a mean value of 12.6 thousand Mg CO2eq/year and a standard deviation of 11.4 thousand Mg CO2eq/year. Per capita, these values range from 10 kg CO2eq/year to 8.4 Mg CO2eq/year, with a mean of 1.1 Mg CO2eq/year and a standard deviation of 1.5 Mg CO2eq/year. In all communes, the contribution of agriculture to total emissions is at an average of 14% (values range from .2 to 57.4%). The obtained results confirm the appropriateness of including emissions from the agricultural sector and other related sources in low carbon economy plans.  相似文献   
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Theoretical and Applied Climatology - On the basis of temperature observations at 60 meteorological stations in Poland, changes in the indices associated with the presence of extremely high air...  相似文献   
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Rotational shear is the type of loading path where samples are subjected to cyclic rotation of principal stress directions while the magnitudes of principal stresses are maintained constant. This paper presents results from an experimental investigation on the drained deformation behaviour of saturated sand in rotational shear conducted in a hollow cylinder apparatus. Two types of granular materials, Leighton Buzzard sand and glass beads are tested. A range of influential factors are investigated including the material density, the deviatoric stress level, and the intermediate principal stress. It is observed that the volumetric strain during rotational shear is mainly contractive and most of strains are generated during the first 20 cycles. The mechanical behaviour of sand under rotational shear is generally non-coaxial, i.e., there is no coincidence between the principal axes of stress and incremental strain, and the variation of the non-coaxiality shows a periodic trend during the tests. The stress ratio has a significant effect on soil response in rotational shear. The larger the stress ratio, the more contractive behaviour and the lower degree of non-coaxiality are induced. The test also demonstrates that the effect of the intermediate principal stress, material density and particle shape on the results is pronounced.  相似文献   
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The study analyses the numbers of days with strong winds in Krakow during the period 2000?C2007 using anemometric records and fire department data. Patterns are identified in the seasonal and annual variation of strong winds. Particular attention is devoted to extreme events. Based on measurements, the study finds that strong winds mostly occurred in winter. Fire department call-out data show that repair of damage caused by strong winds and gusts of wind was needed equally as frequently in summertime. Strong winds accompanying summer storms are often of a local nature and are not always recorded by weather stations. Wind damage was mapped using requests for fire department assistance.  相似文献   
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The low‐temperature thermal history of the Holy Cross Mountains (HCM) is investigated by apatite fission track and apatite and zircon (U–Th)/He thermochronology. Our results provide constraints on the deformation history of Palaeozoic basement rocks in the transition area from Precambrian to Palaeozoic Europe that are exposed from beneath Permian–Mesozoic sediments within the HCM. Late to post‐Variscan cooling of the Palaeozoic strata from maximum temperatures is shown to be a major feature of the HCM. This cooling likely followed a heating event related to burial and/or hot fluid circulation along the Holy Cross Fault in the late Carboniferous. The central part of the HCM shows a rapid cooling event caused by tectonic inversion, which started in the Late Cretaceous. However, this event was less pronounced in the western margin of the HCM, where slow cooling continued throughout the Mesozoic with only minor acceleration of the cooling rate since the latest Cretaceous.  相似文献   
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The Beishan complex is composed of orthogneiss and metagreywacke that both enclose bodies of eclogite and serves as a unique example for comparative petrological study of all these lithologies. The rocks show the earliest regional steep N-S striking fabric (S2) preserved in low strain domains that are reworked by ubiquitous steep N-NE dipping cleavage (S3). The eclogite shows an almost isotropic fabric defined by an M1 assemblage of Grt–Cpx–Amp–Qz–Rt–Ilm that is locally retrogressed to M2-3 amphibolite facies mineral assemblages, with P–T peak at 20–21 kbar and 750–775°C and retrogression to 2–3kbar and 530–550°C. The typical mineral assemblage of the host metagreywackes is Bt–Ms–Pl–Qz−Chl–Ilm±Grt. Rare Al-rich metagreywacke layers are composed of Grt–Ky–St±Sil−And–Bt–Ms–Pl–Qz±Chl±Rt–Ilm giving a P–T path with peak at 8–8.5kbar and ~670°C correlated with the S2 fabric and retrogression to ~2.5kbar and 525–550°C correlated with the S3 foliation. In two eclogite samples, the garnet-whole rock-clinopyroxene Lu–Hf isochrons give ages of 461.9±1.6 Ma and 462.0±6.2 Ma interpreted as reflecting average age of garnet formation, and Sm–Nd isochrons give ages of 453.6±2.7 Ma and 452.8±3.0 Ma interpreted as dating near-peak metamorphism. In metagreywacke, in-situ U–Pb dating of monazite gives two groups of ages of 445–440 Ma (Mnz cores) and 436–429 Ma (Mnz rims), interpreted as reflecting the metamorphic peak and retrogression. Our results show that eclogite was formed during Ordovician by subduction of a continental crust (D1). Eclogite and metagreywacke underwent partly decoupled P–T–t–D paths until their juxtaposition at mid-crustal levels during a first late Ordovician–early Silurian D2 shortening. Coupling of their P–T–t–D paths occurred during exhumation in the Silurian and a second and orthogonal D3 shortening event. The data from the Beishan Orogen are consistent with a collisional intra-Gondwanan orogen located south of the Central Asian Orogenic Belt.  相似文献   
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In Central Europe, river flooding has been recently recognized as a major hazard, in particular after the 1997 Odra /Oder flood, the 2001 Vistula flood, and the most destructive 2002 deluge on the Labe/Elbe. Major recent floods in central Europe are put in perspective and their common elements are identified. Having observed that flood risk and vulnerability are likely to have grown in many areas, one is curious to understand the reasons for growth. These can be sought in socio-economic domain (humans encroaching into floodplain areas), terrestrial systems (land-cover changes – urbanization, deforestation, reduction of wetlands, river regulation), and climate system. The atmospheric capacity to absorb moisture, its potential water content, and thus potential for intense precipitation, are likely to increase in a warmer climate. The changes in intense precipitation and high flows are examined, based on observations and projections. Study of projected changes in intense precipitation, using climate models, for several areas of central Europe, and in particular, for drainage basins of the upper Labe/Elbe, Odra/Oder, and Vistula is reported. Significant changes have been identified between future projections and the reference period, of relevance to flood hazard in areas, which have experienced severe recent floodings.  相似文献   
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