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Narovcova J.,Vyzkumny ustav lesniho hospodarstvi a myslivosti
Zpravy Lesnickeho Vyzkumu | Year: 2010

During five-year period after outplanting of Scots pine in the area of Polabí, mortality in relation to individual populations, groups of populations, planting stock growing regime, and Scots pine as a species was observed. We continuously monitored and evaluated both biotic and abiotic mortality causes such as Armillaria mellea and dry periods. The percentage of 56% of honey fungus Armillaria mellea was determined for the five-year period after outplanting while the remaining percentage belonged to abiotic factors, i. e. temperature and precipitation conditions on permanent site. Source

This study investigated whether differentiation of Scots pine planting stock growing regimes influences its morphological characteristics and whether differences of individual populations in response to offered growing conditions exist. Planting stock growing regimes was decisive for morphological characteristics of produced Scots pine young plants, i. e. it totally suppressed the influence of populations. Source

Peskova V.,Vyzkumny ustav lesniho hospodarstvi a myslivosti
Zpravy Lesnickeho Vyzkumu | Year: 2011

Oak forest (Quercus petraea) in Dfevic was selected for intensive year-round study of mycorrhizal activity and development of oak roots. At this study plot also activity of macromycetes was monitored based on their fructifications. This work presents quantitative data of active and inactive mycorrhizae that were collected monthly by the standard sampling method, thin root dry mass (roots up to 1 mm in diameter) and information about fungi species (qualitative and quantitative). Levels of active mycorrhizae were relatively stable year-round while inactive mycorrhizae showed statistically significant fluctuation with substantial increase after summer. A direct link between these two types of mycorrhizae can be probably explained by a shorter and variable longevity of active mycorrhizae during the season. Source

The paper aims to investigate the effect of mountain pine shrubs on ground air temperatures and relative air humidity in its vicinity. Temperature and humidity sensors were placed 35 cm above the ground in two locations: 1) inside mountain pine shrub, at an edge of the shrub and in a gap, and 2) in detailed transect from a shrub into a gap. Vegetation periods from May to September were evaluated. Ground temperatures inside the mountain pine shrub were the most stable; temperature amplitude grew with increasing distance from the shrub to the gap. However, in sunny days maximal temperatures near the edge of the shrub often exceeded values in forest gap. Relative air humidity of forest gap was lower than in the interior and close vicinity of shrubs, it decreases with an increasing distance from the shrub. Air temperature and humidity gradients of the monitored south-western edges of the mountain pine shrub were short, the influenced space near other more shaded sides of the shrub would reach further. Terrain micro-variability can influence temperature and especially humidity of the ground air layer and suppresses expected differences coming from the distance to the nearest mountain pine shrub. Source

The paper aims to evaluate the temperature dynamics of upper and lower side of shoots of European fir seedlings during spring. Calibrated miniature thermocouples were stuck to the upper and lower surface of needles on shoots of six young firs ca 45 cm in height (i.e. six replications). Two sunny periods with frosts and one overcast period with rain were evaluated. Temperatures were recorded every minute. Data were evaluated in relation to air and soil temperatures, global radiation, wind speed and precipitation recorded every hour. In sunny days, temperatures of upper side of shoots were higher compared to lower side, with maximum difference in about 11 a.m. During cloudless nights, temperatures of lower side of shoots were higher. Afternoon and night temperatures of the lower side of shoots in clear days were increased by convection from soil surface. In cloudy days with rain, the temperature differences during day and night were insignificant. Wind decreased temperature differences in daily and night hours. Source

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