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Forest vegetation is a key factor in the maintenance of global carbon cycle balance under the present climate change conditions. Forest ecosystems are both buffers against extreme climatic events accompanying climate change and carbon sinks diminishing the environmental impact of anthropogenic greenhouse gas emissions. We investigated the influence of stand structure and site characteristics on the productivity and carbon storage capacity of temperate forest types. Predictors of species productivity were parameters such as stand density, age, height, average diameter and wood density. Morus alba (L.) was more productive than average both in terms of annual volume increment and annual biomass gain, while Quercus sessiliflora (Matt.) Lieb. and Quercus frainetto (Ten.) were significantly less productive than average. Differences in stand productivity were explained by stand density, age, height, altitude, type of regeneration and species composition. Statistically significant differences were measured between the productivity of stands dominated by different woody species, with low productive stands dominated by slow growing species with high wood density like Quercus or Fagus, and highly productive stands rich in fast growing species with low wood density like Populus or Salix. Stands with different plant communities in the underlying herbaceous layer also tended to have different levels of productivity.
Large-scale stone-banked lobes and terraces are distributed over an area of 1 km2 of gentle slope on Rink Plateau in the northern part of James Ross Island, Antarctic Peninsula region. Topographically, there are two main features: relatively high risers up to 5 m high and distinct frontal ridges. In order to understand the processes responsible for these lobes and terraces, the authors have monitored air and ground temperatures and movement of stones on the surface over the period 1995-2005. In February 2005, the subsurface structures were surveyed by ground penetrating radar and drilling. The ground penetrating radar profiles identified the bedrock surface. The surface morphology of the lobes corresponds closely with that of the bedrock. The relatively high risers of these lobes are presumed to be due to a cessation of frontal advance.
Native starches, such as potato, wheat, maize, and waxy maize, were subject to oxidation with sodium chlorate(I), hydrogen peroxide in the presence of Cu2+ ions, and sodium chlorate(III) in the presence of formaldehyde. Native starches and their modified preparations were determined for the content of carboxyl and aldehyde groups. In order to determine changes in the internal structure of starch granules, thermodynamic characterization of phase transitions (DSC) was taken and the degree of crystallinity with X-ray diffractions was determined. Potato starch, after oxidation with the applied reagents, became slightly more crystalline, while cereal starches were affected very little. The thermodynamic gelatinization indices obtained for oxidized starches were only changed a small amount in comparison to native ones, which means that the internal structure of the granules is almost unaffected by oxidation.
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The objective of the research is to compare the importance of agribusiness in the economies of the EU countries. The results suggest that the agribusiness share in national economy and its internal structure depends on the country’s level of economic development. In the better developed countries the share index value is low, while in the less developed countries it is relatively high. The main condition for changing the situation in Poland is to generate an economic growth.
W artykule przedstawiono badania mające na celu porównanie struktury wewnętrznej oraz właściwości przemiałowych ziarna orkiszu (odmiana Schwabenkorn) oraz pszenicy zwyczajnej (odmiany Legenda i Parabola). Ziarno pochodziło z uprawy ekologicznej z doświadczenia przeprowadzonego w sezonie 2009/2010 w Stacji Doświadczalnej Osiny, należącej do IUNG-PIB w Puławach. Struktura wewnętrzna orkiszu była podobna jak ziarna pszenicy zwyczajnej odmiany Legenda, cechowała się luźnym ułożeniem ziaren skrobi i białka. W porównaniu z ziarnem pszenicy zwyczajnej, ziarno orkiszu cechowało się istotnie mniejszą masą 1000 ziaren, gęstością w stanie usypowym, wyrównaniem oraz większą zawartością popiołu. Wydajność mąki ogółem uzyskanej z przemiału ziarna orkiszu była na podobnym poziomie jak z ziarna pszenicy zwyczajnej odmiany Legenda, istotnie więcej mąki uzyskano z przemiału ziarna odmiany Parabola. Nakłady energetyczne na przemiał ziarna orkiszu były istotnie niższe w porównaniu z ilością energii zużywanej podczas przemiału ziarna pszenicy zwyczajnej.
Deep and multi-level economic transformations that occurred in the cities and rural areas caused profound changes in the demographic structures. The problems connected with the issue of the demographic transformations in the cities, especially those big ones, such as agglomerations or metropolises, have remained a subject of numerous geographic, demographic or sociologic studies in the post-war period. It was a result of a high concentration of population in the analyzed units, their economic position and the role they played in the settlement network of a country. The main purpose of the present paper is to define the general mechanisms of social, demographic and set-tlement transformations in the coastal agglomerations, being developed and influenced by various factors influencing development patterns of their inner zones. The author analyzed the changes of demographic and social structures recorded between 1988 and 2006 and accommodation re-sources. Analyzing the changes of population patterns by their inner spatial structure, the author discovered an increasing number of inhabitants recorded in each zone, however generally more dynamic development patterns characterized the urbanized zones (Fig. 1). The author also re-corded considerable changes of accommodation resources increase concerning their general and ownership structure during the analyzed period (1988-2006). Estimation of demographic transfor-mation factors including concepts of natural increase and migration rate is considered an essential element in conducting the research on population dynamics (Fig. 3 and Fig. 4). The observed ten-dencies of population’s structures were also recorded in economic groups (population in pre-production, production and post-production age). Generally the author observes a significant in-crease of people in production and post-production age. The number of children and teenagers un-der 18 has considerably decreased – pre-production group (Fig. 5).
Fragments of rhabdosomes isolated by chemical treatment from an erratic boulder of Baltic origin and ?Middle Ordovician age, provisionally assigned to Mastigograptus aff. tenuiramosus (Wallcott, 1881) were studied with SEM. Although exceptionally well preserved, remains lack the thin−walled free portions of thecae. Rhabdosomes are provided with a strongly developed basal disc, short stem and many branched stipes. The latter consist of heavily corticalized chains of stolothecae with alternately disposed thecal bases. Stolothecae display a morphological gradient and increase in size and change in shape distalwards. The stolon system studied with SEM on naturally and artificially broken specimens, as well as traced through open thecal bases, reveals a regular triad budding but no stolon inside the stolothecal cavity. We tentatively suggest that crassal lining, recognized earlier by TEM studies, corresponds to an unusually inflated stolonal stolon, filling the entire thecal cavity and adhering tightly to stolothecal wall. The systematic position of Mastigograptus, a matter of long debate, seems to be defined by a number of structural features which imply a distinct difference between genus in question and all known orders of sessile graptolites. The order Mastigograptida nov. and the family Mastigograptidae nov. are proposed.
Absorption, transmission and scattering of visible light by potato starch granules were studied using simultaneously crossed polarised and non- -polarised light or red laser beam microscopy (CLBM). Novel optical phenomena were discovered. In our paper they are called the lens, light guide, internal cross, and hedgehog effects. They contribute to the knowledge about interaction of visible light with internal structure of starch granules. These kind of observation might be useful in estimation of the granular starch quality and influence of physical, chemical, and enzymatic processing on the internal organisation of granules. The method is non-destructive.
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