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PL
Celem pracy było określenie wpływu siedliska leśnego na zróżnicowanie jakościowe substancji humusowych w poziomach próchnic nadkładowych gleb leśnych tworzących się w pobliżu starodrzewu Quercus robur (200 – 600 lat). Analizowane gleby były zlokalizowane na terenie obszaru chronionego krajobrazu – w Borach Niemodlińskich i Lasach Stobrawsko-Turawskich. Badane gleby reprezentowały 15 profili zaliczanych do bielic, gleb brunatnych właściwych i kwaśnych. Specyfika i troficzność siedliska leśnego wpłynęły na ukształtowanie właściwości fizykochemicznych i chemicznych analizowanych gleb leśnych, co wyrażało się przede wszystkim w ich kwaśnym odczynie, zróżnicowanym zasoleniu jak i właściwościach optycznych substancji humusowych. Jednocześnie stwierdzono ilościowe zróżnicowanie materii organicznej w analizowanych poziomach gleb wyrażone wartością współczynnika zmienności (V) równą 61%. Uzyskane wyniki analiz chemicznych i wartości indeksów A2/4, A2/6, A4/6, ΔlogK oraz współczynników korelacji wskazują, iż w badanych glebach procesy transformacji materii organicznej prowadzą do wytworzenia substancji humusowych o niskim stopniu humifikacji i ilościowym zróżnicowaniu w profilach. Zmienność analizowanych właściwości charakteryzujących jakość substancji humusowych wskazuje, iż transformacja materii organicznej poziomów ektohumusowych zależy w dużym stopniu od jakości siedliska, w tym od rodzaju dopływającej materii organicznej.
EN
The aim of this work was to determine the diversity of qualitative humic substances in the ectohumus horizon of the forest soil profiles. The analyzed soils were located in protected landscape areas and nature parks – Bory Niemodlińskie and Lasy Stobrawsko-Turawskie, and occurred under the tree stands of trees which were 200 – 600 years old – Quercus robur. The analyzed soils represent 15 soil profiles belonging to Podzols, Cambisols and Dystric Cambisols. Properties of forest habitat specificity influenced the physicochemical and chemical properties of the analyzed soils. We observed particularly strong expressions of acidity, pH and salinity, and a diversity of chemical and optical properties of humic substances. The content of organic matter in the analyzed soil horizons showed considerable variation, as indicated by a coefficient of variation (V) equal to 61%. The composition of humic substances of forest litter is characterized by a gradual change of functional groups that usually consists in the decrease of carbohydrates, the relative increase of carboxyl and alkyl carbon, and decay of lignin. In the investigated soils, we observed that the transformation processes of organic matter led to humic substances which were predominantly humus with a lower level of humification, as evidenced by the indexes: A2/4, A2/6, A4/6, ΔlogK. Therefore, variation of the observed properties of humic substances indicates a different direction in the transformation process of organic matter. Such a transformation depends very much on the habitat and nature of supplied organic matter.
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EN
Litter production is essential for transfer of energy and nutrients from plant to soil. This paper aims to relate the phenology of litter-fall by common oak (Quercus robur L.) to specific climatic factors. Over three years, two natural stands of Quercus robur (Cerceda with latitude 43 degrees 11'N and longitude 8 degrees 28'W and Lourizan with latitude 42 degrees 25'N and longitude 8 degrees 40'W) near to fifty years old and located in Galicia, Northwest of Spain, were thoroughly studied in the period 1992-1994. The litter was collected in five litter traps (0.5 m wide, 20 cm high) located within a plot of 100 m2. Annual litterfall values were similar in both stands, being approximately between 6 and 11 Tm [dot] ha^-1 (dry weight); the southern stand showed a higher interannual variability. The leaf fraction accounted for the highest percentage of total litter production. Usually it represents more than 70% of annual production, but it has been exceeded by fruits production in the corresponding season (spring in the north and summer in the south). The climatic parameters that had the greatest influence on litter production were total precipitation and absolute maximum temperature with a correlation always higher than 65%. It allows to link litter production with climate parameters with an adjusted correlation coefficient around 70 %, even more in the south plot (Lourizan). With an easy ANOVA analysis it is possible to distinguish the season with greater litter production; it is the autumn in all cases except fruits production as was said above.
EN
Climate-growth relationships in Quercus robur chronologies for vessel lumen area (VLA) from two oak stands (QURO-1 and QURO-2) showed a consistent temperature signal: VLA is highly correlated with mean April temperature and the temperature at the end of the previous growing season. QURO-1 showed significant negative correlations with winter sums of precipitation. Selected climate variables were used as predictors of VLA in a comparison of various linear and nonlinear machine learning methods: Artificial Neural Networks (ANN), Multiple Linear Regression (MLR), Model Trees (MT), Bagging of Model Trees (BMT) and Random Forests of Regression Trees (RF). ANN outperformed all the other regression algorithms at both sites. Good performance also characterised RF and BMT, while MLR, and especially MT, displayed weaker performance. Based on our results, advanced machine learning algorithms should be seriously considered in future climate reconstructions.
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EN
Pedunculate oak (Quercus robur L.) is considered the main commercial tree species in conditions of floodplain forests of central Europe. In the Czech Republic clear-cutting silvicultural system represents a prevailing regeneration method of oak stands in floodplain forest. The natural regeneration is limited only in stands and years with sufficient acorn production. We analysed an acorn crop periodicity and an influence of canopy opening to the acorn production in South Moravian floodplain forest, Czech Republic between 2008 and 2011, The acorn crop from trees with different growth spaces in four stand conditions (closed canopy (A), moderate open canopy (B), open canopy (C) and single growing trees (D) with unlimited growth space was analysed. The amount of acorns was determined using seed traps placed under the crowns of sample trees. The average amount of acorns in 2009 and 2011 ranged from 13 (A) to 102 (C)/m2 and from 2 (A) to 124 (D)/m2, respectively. At the same time, a considerable difference was recorded in the fructification of sample trees in the various stand situations. Significant correlations were confirmed between the amount of acorns and crown size (r2 2009=0.27, r2 2011=0.07) of parent trees and their growth space – release area (r2 2009=0.42, r2 2011=0.25) and social area (r2 2009=0.31, r2 2011=0.26). The production of acorns could be affected by establishing conditions for the pedunculate oak with a minimum crown projection area in adult trees of at least 70 m2 and/or with a minimum release area of 300 m2, it means spacing between parent trees about 10 m or 100 trees per 1 ha.
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Content available Model wzrostu dla drzewostanów dębu szypułkowego
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EN
Old Common Oaks (Quercus robur L.), often connected with myths and legends, are the largest trees occurring in Central Europe. The present paper describes twelve largest girthed specimens of the species growing in Poland. Authors, based on their own measurements and researches, prepared a ranking list of these unique trees and estimated their health condition. Moreover, their exact localizations in Mielno, Bąkowo, Piotrowice, Kadyny, Januszkowice, Zagnańsk, Rogalin, Nogat, Węglówka, Młock, Rudka and Karczmiska were described and most popular facts and stories from their history were given. The largest girthed Common Oak in Poland is “Napoleon” growing in Mielno (1042,5 cm in circumference), the second one is the oak from Bąkowo (1020 cm) and the third – “Chrobry” from Piotrowice. In total in Poland there are three specimens of Common Oaks with trunk circumference of more than 1000 cm, and five more with circumference between 900 and 1000 cm.
PL
Dęby Rogalińskie stanowią największe skupisko starych dębów szypułkowych w Polsce i jedno z największych w Europie. Rosną one w okolicach Rogalina w rozleglej, płaskiej dolinie Warty, na odcinku od Rogalina do Świątnik po prawej i lewej stronie rzeki. Celem pracy była dokładna inwentaryzacja populacji starych dębów tworzących na tym terenie interesujący i unikalny krajobraz. Wszystkie drzewa (o obwodzie minimum 200 cm, mierzonym na wysokości 1,3 m od powierzchni ziemi) zostały zmierzone, opisane i naniesione na mapę. Ogółem odnotowano 1435 drzew. Wśród nich 284 to dęby pomnikowe o obwodzie powyżej 360 cm.
EN
Rogalin Oaks is the largest concentration of old Common oaks in Poland and one of the largest in Europe. They stand in Rogalin and its countryside from Rogalinek to Świątniki in the widespread valley of Warta River on both banks of the river. Tire aim of the study was a precise listing of population of old oaks which make an interesting and unique landscape. All trees (over 200 cm circumference at the breast height) were measured, described and pointed at the map. 1435 individuals were recorded in this area. 284 of them are Monuments of Nature (over 360 cm circumference).
EN
The main properties of the soils under oak (Quercus robur L.) forests in Galicia (NW Spain) were characterized. Eleven edaphic parameters (pH, OM, N, C/N ratio, P, K, Ca, Mg, sand, silt and clay) were estimated in 39 soil samples. Siliceous substrates were present in all stands and the soils were found to be the cambisols. The values of chemical parameters are similar to those considered as the optimal ones by other authors (i.e., average pH close to 5, average C/N ratio close to 15) with the exception of the organic matter which is slightly higher; the average value is equal to 8.64 ± 5.19. The content of nutrients can be considered as the low or medium (for instance, the potassium is only 73 ppm) as compared with other forests in the study area, except the content of phosphorus, which is considerably higher (21.8 ppm versus 1–6 ppm).
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