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The present study discusses: - hydrogenic soil-forming sites found in the studied valley area distinguished into moistlands, mudlands and peatlands, - types of hydrological feeding of sites, including fluviogenous sites as the prevailing type, as well as soligenous sites, - soils and the ongoing soil processes, distinguishing the following soil types: peaty-gley and mud-gley soils subjected to paludification, paludified peat and mud-peat soils, - post-paludic peat-moorsh soils in the 1st or 2nd stage of the moorsh-forming process, post-paludic mud-moorsh soils, - post-paludic mineral-moorsh, moorshy proper and mineral-moorsh soils. Areas occupied by the above-listed units are described. Soil types are indicated on a map by contours. Results of a survey of soil-site conditions in the studied stretch of the Narew Valley were used in describing its natural and productive status. Emphasis was placed on the valley’s exceptional site diversity associated with the rich micro-relief of its floor. It was concluded that the optimal level of hydration in the valley is the one making it possible to maintain half of the acreage of hydrogenic sites in the phase of accumulation which would help to reconcile nature protection goals with the requirements of agriculture. Also discussed were factors supporting the adverse phenomenon of a gradual dehydration in the valley. Environmental engineering schemes implemented in this section of the Narew valley should be aimed at optimizing and stabilizing the described conditions as well as eliminate factors which assist dehydration.
The investigations were carried out in the Upper Narew river valley over the length of about 120 km - from the state frontier to the Biebrza mouth. The valley is paludified in the middle part of this sector and is cut there by many - channel river and his in the remaining sectors the muddy-alluvial and alluvial character. The Upper Narew river valley is developed in Quaternary sediments. Many geomorphological forms have the polygenetic and transitional character. The valley was formed during the areal deglaciation of the Warta glacier. The result of the deglaciation course is lack of possibility for creating large area of the soligenous habitats and therefore the fluviogenous habitats prevail in the valley. The relief of the valley bottom is the important factor which caused the differentiation of the habitats. It is an effect of the deglaciation course of the Warta glacier and also the later changes during the Wisła glaciation period and the changes during the Holocene. The connection between ground waters and river waters is observed in the Upper Narew river valley. The connection is also between ground waters and intermoraine aquifers waters. On the large areas of valley the intermoraine aquifers waters supply the ground waters.
The Scots pine is one of the most important species in European and Asian forests. Due to a widespread occurrence of pine forests, their significance in the energy and mass exchange between the Earth surface and the atmosphere is also important, particularly in the context of climate change and greenhouse gases balance. The aim of this work is to present the relationship between the average annual net ecosystem productivity and growing season length, latitude and air temperature (tay) over Europe. Therefore, CO2 flux measurement data from eight European pine dominated forests were used. The observations suggest that there is a correlation between the intensity of CO2 uptake or emission by a forest stand and the above mentioned parameters. Based on the obtained results, all of the selected pine forest stands were CO2 sinks, except a site in northern Finland. The carbon dioxide uptake increased proportionally with the increase of growing season length (9.212 g C m-2 y-1 per day of growing season, R2 = 0.53, p = 0.0399). This dependency showed stronger correlation and higher statistical significance than both relationships between annual net ecosystem productivity and air temperature (R2 = 0.39, p = 0.096) and annual net ecosystem productivity and latitude (R2 = 0.47, p = 0.058). The CO2 emission surpassed assimilation in winter, early spring and late autumn. Moreover, the appearance of late, cold spring and early winter, reduced annual net ecosystem productivity. Therefore, the growing season length can be considered as one of the main factor affecting the annual carbon budget of pine forests.
Badania ekosystemów leśnych są niezbędne do oceny ich wpływu na globalny bilans CO2. Prowadzone są już w wielu krajach europejskich takich, jak Niemcy, Finlandia czy Czechy. Również w Polsce uruchamiana jest pierwsza stacja pomiarowa, na której prowadzone są pomiary wymiany gazów i ciepła między atmosferą i lasem oraz pomiary biomasy. Ulokowana jest ona na terenie nadleśnictwa Tuczno. Do oceny wielkości strumienia netto dwutlenku węgla ekosystemów leśnych stosowana jest powszechnie metoda kowariancji wirów. Wymaga ona zastosowania skomplikowanych i wyrafinowanych urządzeń pomiarowych. Pomiar wielkości biomasy nadziemnej, a tym samym ilości ulokowanego w lesie CO2 może być uzupełnieniem wyników uzyskanych dzięki zastosowaniu metody kowariancji wirów. Oszacowanie biomasy leśnej może być wykonywane zarówno metodami tradycyjnymi, jak i przy pomocy nowoczesnych technik teledetekcyjnych. Badania te wykonywane są m.in. przy pomocy nowatorskiej techniki naziemnego skaningu laserowego, uzupełnionej laserowym skaningiem lotniczym, wysokorozdzielczą cyfrową ortofotomapą i zdjęciami hemisferycznymi.
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