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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.
The level of shoot damage and the annual radial increment were estimated in Scots pine stands affected by a severe maturation feeding of pine shoot beetles Tomicus piniperda (L.) and T. minor (Hart.). Studies were conducted on sample plots situated about 60 and 500 m from sawmill timber storage sites during 2001-2005. In both investigated stands the radial increment in 2003 was smaller than that in 2002. There was no significant difference between the damaged stand and the control stand in respect of its relative value. The relative value of radial increment during the period 2003—2005 showed that a severe maturation feeding of pine shoot beetles had no effect on weakening of increment dynamics of trees in the edge part of the stand.
Austrian pine (Pinus nigra Arn.), a species introduced into Polish forests, underwent dendroclimato- logical research using the response function method. The researchers analised the annual width increment against the climatic conditions of three populations of trees from the Nizina Wielkopolska and the Jura Krakowska. It was determined that among factors affecting the process of xylene cell formation in the analised trees, thermal and pluvial conditions had a relatively largeimpact. It is expressed in the coefficient of determination (R2) which had the following values: 44, 48 and 50%.
This paper discusses the results of analyses of the influence of temperature and rainfall on the width of tree-rings formed by the Douglas fir (Pseudotsuga menziesii Franco) in the years 1930-1997. The researchers selected six tree stands in the area of the Sudety Mountains. They determined that the size of the radial increments of the Douglas fir was significantly influenced by the temperatures of cold part of the year, before the vegetation season, and by those of the summer. Thermal conditions determined mainly the similarity of the rhythm of variability of tree-ring sizes. In addition, rainfall occurring in winter and during the vegetation season had Lin important, though less significant, impact on the formation of the annual increment. The influence of rainfall during the vegetation season was smaller in the case of trees from the sites located at higher altitudes and in the western part of the Sudety, which is abundant in rainfall. The spatial diversity of rainfall in the area of the Sudety was, probably, the most fundamental factor which caused the variability of the degree of similarity of the incremental rhythm of the trees from particular sites. Despite this fact, however, the Sudety Mountains can be considered as a dendrochronologia И у homogenous region for the Douglas fir.
The relative crown length, needle loss, and vitality of fir trees of older (above 160 years of age) and younger (from about 70 to about 130 years, with single trees up to 160 years of age) generations were significantly correlated with the current 10 year, (1985-1994), radial increment at breast height. In the case of trees of the younger generation the type of tree-top and the degree of crown deformation were also significantly correlated with the radial increment at breast height. The best growing fir trees of the younger generation were characterized by narrow conical (trees 41 to 60 years of age at breast height) to flattened (trees 101 to 120 years of age at breast height) tree-tops, well-proportioned or little deformed (loeses up to 20%) crowns, and a relative crown length amounting to at least 56%.
The paper describes evaluation of spruce radial growth variability, based on of synchronized individual increment sequences (dendroscales). The empirical material were increment samples from 215 trees, growing on ten research plots in the Silesian and Żywiec Beskids. For each plot in each year there was calculated the raw average chronology, indexed chronology and the coefficient of variation for incremental indexes. In addition, an analysis of the occurrence of pointer years was performed. The observed medium-term changes of the analyzed incremental indices lead to conclusion that in the second half of the twentieth century, a certain external factor influenced the growth of tested spruces. Both the obtained results and the existing studies provide a basis for an assumption that this factor was mainly air pollution.
W pracy określono trend przyrostu grubości drzew i jego zmiany w drzewostanach sosnowych IV/V klasy wieku rozwijających się pod wpływem imisji przemysłowych i na jego podstawie oszacowano straty na przyroście grubości w drzewostanach I, II i III strefy zagrożenia w stosunku do drzewostanów kontrolnych (strefa 0).
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