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The growth parameters of the Vaccinium myrtillus shoots were studied on a vertical transect crossing localities “Muraň“ (1080–1110 m a.s.l., skeli-humic podzols, Fageta abietino-piceosa) and “Hliniky“ (950–960 m a.s.l, dystric cambisols, Abieti-Fageta inferiora) in the protected zone of the National park “Slovensky raj“ (Spiš region, East Slovakia). In the localities, both contaminated by air pollution research plots in undamaged and damaged (with lower stand density and canopy compactness) spruce ecosystems were established. The content of Al and Cr was significantly higher in cambisols, and that of Cd – in podzols. The limit values calculated for both soils have been exceeded only in case of mercury. The Al content in bilberry twigs exceeded the background values (by 44–76%) in case of the both plots situated on locality “Muraň”, and that of Ni and Pb concentrations (by 3–60%) only on damaged plot. The mean content of Ni and Pb was significantly higher in bilberry twigs growing on podzols and the mean content of Al was significantly higher in plants on undamaged plots. The mean length, weight as well as energy content of bilberry twigs were significantly higher in damaged spruce plots (on average by 33%), probably due to favourable light conditions.
The paper provides some guidelines on the choice of the target species compositions for plantations that would replace monocultural spruce stands growing on the sites of the Silesian Beskid Mts. Part of the guidelines relates to the rules governing the sequence in which the monocultures will be converted into mixed stands. It is suggested that those rules should be combined with the principles of the establishment of progenyplantations. The seed stands of the Istebna spruce are experimentally divided into four categories according to their abilityto perform the function of a seed stand. The following features of the stands are analysed: vitality, density, stage of regeneration, protective and cultural functions. The paper contains also an outline of the methods of species conversion and the relevant references.
Hurricanes, high temperatures and drought have caused damage to forests in the Żywiec Beskids. The effect of extreme weather events on the population of Ips typographus was examined in the damaged spruce stands in the period of 2005-2007, using pheromone traps for catching beetles. The daily average number of trapped beetles in a single pheromone trap ranged between 32 and 72 in subsequent growing seasons. It was proved that thermal conditions at different altitudes affected the beginning and the course of I. typographus swarming. Three swarming peaks were observed in each of three consecutive growing seasons. Extremely high temperatures in 2006 did not increase the number of swarming peaks. In 2007 the number of beetles in pheromone traps was twice higher than in the first year of the study.
In the experiment eight populations of Picea abies were chosen at 100 m intervals between 500 m and 1200 m altitude a.s.l.. In each population wood core samples were collected from 14–19 trees (126 cores total), and measured using a Corim Maxi device. At four of the eight sites (every 200 m in elevation between 500 m and 1100 m a.s.l.), the diversity of ground vegetation was evaluated, and temperature was recorded at every 100 m of altitude. The highest average radial increment of spruce occurred between the altitudes 800–1000 m a.s.l., which is probably the optimum for spruce. The larger increment indices observed at higher altitudes may signify a high growth potential of spruce. It may also suggest a recent upward shift of the optimum growth zone for this tree species. In 15 phytosociological records, the presence of 148 plant species forming plant associations: Dentario glandulosae- Fagetum typicum (sub-mountainous and mountainous form) and Abieti-Piceetum, and community Abies alba-Rubus hirtus, was documented. No relationship was found between ground vegetation species diversity (expressed by Shannon-Wiener index) and levels of stand diversity. The vegetation species diversity varied with the elevation above sea level: the highest plant diversity was found at 500 m a.s.l., and decreased with increasing altitude. The potential increase in air temperatures may result in changes to the altitudinal range of many plant species including trees, and consequently in an upward shift of the boundaries of plant zones; in this case the sub-mountainous and lower mountainous forest zone. In this region, the optimal zone for Norway spruce may be restricted to the highest elevations.
W pracy stwierdzono, że jedynie drzewostany Beskidu Żywieckiego (masyw Pilsko-Romanka) do wysokości około 900 m n.p.m. rozwijają się w warunkach, które na podstawie tendencji przyrostowych uznać można za niezakłócone. Największy spadek przyrostu grubości i zahamowa­nie jego dynamiki w okresie 1977-1986 w porównaniu z 10-leciem 1967-1976 stwierdzono w obrębie Szczyrk (masyw Skrzyczne), szczególnie w partiach przygrzbietowych (ok. 1100 m n.p.m.). Wykazano również, że stopień zahamowania dynamiki przyrostu grubości istotnie zależy od wysokości położenia drzewostanu n.p.m. Nie zależy natomiast od wystawy ani też liczby drzew w drzewostanie w obrębie danej wysokości n.p.m.
The aim of this study was to determine the virulence of H. parviporum genets with known genetic similarity and representing pathogen's population, which infested a part of Norway spruce stand. Genets caused average 47% mortality of spruce seedlings in infection experiment in vitro. The mortality rate varied from 16% to 80%. In infection experiment in vivo the mycelium of H. parviporum caused the wood necrosis on distance from 0.8 to 7.78 mm. 56% of genets of investigating population characterized by high virulence, 22% by average and 22% by low virulence.
The study presents the results of investigation on reaction of beech (Fagus sylvatica L.) leaves observed next year after planting seedlings in different positions in a young spruce stand located in upper mountain conditions. The methods of chemical analyses and assessments of chlorophyll fluorescence were applied with the aim to evaluate a course of leaf adaptation. In the young spruce stand located in the Karkonoše Mts, bare root beech seedlings after cultivation in full light were planted into three main positions to spruce trees (under the crown, within crown perimeter and in stand gaps). Next year after planting, the total biomass, leaf nutrient content and chlorophyll fluorescence parameters were evaluated. The beech trees planted under spruce (Picea sp.) crowns had significantly lower specific leaf mass and the mean leaf area was decreasing from shade to sun. Differences in nutrient contents were not significant between the treatments. We found significantly higher values of minimal (F0) and the maximum fluorescence (Fm) as well as of the maximum quantum yield of PSII photochemistry (Fv/Fm) in the leaves of beeches growing under the spruce crown. Significant differences among treatments were found also in the courses of the values of maximum fluorescence yield Y(II) and nonphotochemical quenching (NPQ). Our study indicated that bud forming processes are only partially responsible for physiological properties of beech leaves evaluated next year after planting. Photosynthetic performance is also influenced by actual growing conditions. A great part of acclimation occurs already in the first year after planting (change of the light conditions). We speculate that this phase of gradual acclimation of the assimilation apparatus can be one of the reasons of physiological weakening of the plant after planting to different light environment.
It was found on the basis of measurements of material taken in 21 sample plots, established in spruce forests of age classcs IV and V (Table 1), that: 1. The altitude of the stand above sea level decisively affected the formation of valuation traits. Their values (Tables 1 and 2) and (he index of dynamics of diameter increment (Table 4) suggest that the best conditions of growth and development of spruce are found at the altitude of about 900 m. 2. The increment in diameter decreased with the age of stands and also with the altitude, i.e., with the worsening of habitat conditions (Table 3, Fig. 1). 3. The variation in diameter increment increased with the age of stands and decreased with the altitude above sea level (Table 3, Fig.2). This regularity did not concern the other traits (d, h and v) which showed the least variation in stands at 900 m, a greater one at 1100 m, and the greatest variation at 700 m (Table 2).
The health condition of spruce stands in the Moravian-Silesian Beskids is affected by several predisposition factors, the most important of which is the allochthonous character of spruce grown on improper sites. When exposed to a low supply of nutrients and intensive mechanical damage mainly by game, the trees are susceptible to rot infestations, climatic agents and mechanical destruction by snow, hard rime and wind. At present, air pollution does not show any significant impact on the spruce stands; it rather acts as a less important predisposition factor on mountain peaks. The physiological condition of trees is not impaired to the extent which would facilitate infestation with phytophagous or cambioxylophagous insects.
W pracy podano cechy drzewa (tzw. modelowego) warunkujące ponadprzeciętny przyrost 10-letniego pola powierzchni przekroju pierśnicowego. Określone cechy morfologiczne drzew modelowych można traktować jako pożądane dla drzew dorodnych.
Przeprowadzone w 1994 roku badania kontrolne wykazały, w porównaniu do 1984 г., bardzo wyraźne zmniejszenie się zasobności drzewostanów (w granicach ud 30 do 72 m na czterech powierzchniach i nieznaczny jej wzrost na jednej (o 2,9 m /ha); ponadto zwiększyła się bardzo znacznie miąższość posuszu, żywych złomów i leżaniny. Zachodzące procesy zakłóciły, jak należy przypuszczali, naturalne tendencje rozwojowe borów pierwotnych, wyrażające się następstwem charakterystycznych stadiów i faz. Przyczyną tego jest najprawdopodobniej nałożenie się szkodliwego oddziaływania wywalających wiatrów i śniegu waz osłabienie żywotności świerczyn przez imisje przemysłowe.
The paper presents the dimension of damage in fir and spruce upgrowth during light felling, carried out in predominant stand of mountain forests. The work was limited to the analysis of damage in up growth. Weak relation between the quantity of obtained wood and the dimension of damage in renovations defined to what extent the morphological build of predominant forest and trees location in the area influence the dimension of damage during cutting. Total dimension of all types up growths damage ranged from 2.6 to 12.6 in pine stand and from 1.7 to 4.7 in spruce stand.
The amount of water stored in forest soils was estimated on the basis of 358 experimental trials with 18 monoliths taken from forest soils. Rainfall was simulated in two cycles of different length of break between rainfall events. The results showed, that the amount of water stored in forest soils was influenced both by the initial moisture content in samples and by the length of time between consecutive rainfall events (duration of drying). The ascertained differences in the amount of water stored in a sample amounted from 30% to 200% and were larger in case of longer breaks between consecutive rainfalls. The results can be explained by the differences in duration of water absorption by the particles of organic matter. The results indicated also, that the maximum amounts of water stored after a single rainfall event in organic layers of forest soils is larger than the maximum amount stored in the organic layer of a meadow soil of similar depth.
Praca zawiera charakterystykę wybranych tech górnoreglowych drzewostanów świerkowych o charakterze pierwotnym, znajdujących się w rezerwacie ścisłym Tatrzańskiego Parku Narodowego. Badania przeprowadzono na 5 klasycznych, stałych powierzchniach doświadczalnych, w latach 1990-91 Na podstawie liсzby drzew, zasobności drzewostanów, krzywych rozkładów pierśnic i wysokości, budowy warstwowej, struktury wieku, żywotności, miąższości posuszu stojącego i leżącego oraz liczebności odnowienia scharakteryzowano budowę i strukturę oraz stadia i fаzу rozwojowe tych drzewostanów.
W pracy oceniono tendencję przyrostową badanych drzewostanów. Określono wpływ wybranych cech morfologicznych korony, żywotności, jakości pnia oraz masy systemu korzeniowego na wielkość 10-letniego przyrostu pola powierzchni przekroju pierśnicowego świerka i modrzewia.
The regression formulas indicate a significant relationship between the initial moisture content and the density of soils with different content of organic matter. Differences in soil density can also explain the variability in the amount of water stored after a single rainfall episode Statistical tests indicated, that soil density explains 77% of the variability in the optimal initial moisture content and 69% of the variability of the largest increases in the amount of water stored in the sample. For the experiments with longer breaks between two consecutive rainfall episodes the error of estimation was smaller than for experiments with shorter breaks: this suggest, that the time of absorption of water by the organic matter in forest soils is also an important factor.
Badano tempo epifitozу opieńki w 45- i 60-letnim drzewostanie świerkowym w Leśnym Zakładzie Doświadczalnym w Krynicy. Stwierdzono, że sprawcą tej epifitozy był grzyb Armillaria obscura (Sekret.) Hermk przy współudziale Heterobasidion annosum (Fr.) Вref.
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