Testowanie potomstwa hybrydowego i różnych gatunków rodzaju Abies dla leśnictwa, ogrodnictwa ozdobnego oraz produkcji choinek

The paper evaluated dendrometric parameters of hybrid progenies of various Abies species obtained during measurements in the spring 2010 on the research plot in Kostelec nad ýernými lesy. Data were processed and compared to the measurement taken in 2004. Results show that all hybrid progenies within the plot exceeded A. alba in investigated parameters. Only two of the progenies achieved worse results in mean height – A. koreana × (A. cilicica × A. cephalonica) and progeny of spontaneous hybrid no. 2. Considering height and diameter A. nordmanniana was evaluated as the most productive. On the contrary A. gracilis is considered unsuitable for further culture and research due to the mortality of 100%.Niniejsza praca ocenia parametry dendrometryczne hybrydowego potomstwa różnych gatunków Abies otrzymane podczas pomiarów wiosną 2010 na poletku doświadczalnym w Kostelec nad Černými lesy. Otrzymane dane były przetworzone i porównane z pomiarami poczynionymi w roku 2004. Wyniki pokazują, że całe potomstwo hybrydowe na poletku przewyższało A. alba pod względem badanych parametrów. Tylko dwa osiągnęły gorsze rezultaty, jeśli chodzi o średnią wysokość – A. koreana × (A. cilicica × A. cephalonica) oraz potomek spontanicznej krzyżówki no. 2. Pod względem wysokości i średnicy, A. nordmanniana oceniono jako najbardziej produktywną. Z kolei A. gracilis uważa się za nieodpowiednią do dalszej uprawy i badań ze względu na 100% śmiertelnoś

Comparison of different ground techniques to map leaf area index of Norway spruce forest canopy

The leaf area index (LAI) of three monocultures of Norway spruce (Picea abies (L.) Karst), different in age and structure, was measured by means of two indirect optical techniques of LAI field mapping: 1/ plant canopy analyser LAI-2000, and 2/ digital hemispherical photographs (DHP). The supportive measurements with the TRAC instrument were conducted to produce mainly the element clumping index. The aim of the study was to compare the performances of LAI-2000 and DHP and to evaluate effect of three different sampling strategies on field estimation of leaf area index. One of the suggested sampling designs introduced spatial oversampling around one-point measurement. The oversampling was expected to reveal the importance of sampling point position with respect to surrounding trees. In general, the LAI-2000 instrument produced higher estimates of effective leaf area index than DHP in all experimental stands. On the other hand, the higher "true" estimates of LAI were obtained from DHP. All three sampling strategies produced consistent estimates of effective and "true" LAI in all forest sites. The spatial oversampling of LAI measurement point did not significantly improve the LAI estimate of the canopy subplots

Fine roots of Picea abies compensate for drought stress in the rainfall reduction experiment

This study evaluates the influence of repeated artificial drought stress on the fine root charac- teristics – including ectomycorrhizae – of Norway spruce [Picea abies (L.) Karst]. The experimental site consisted of two plots in a mature spruce monoculture stand. The water regime at parts of both plots was regulated by shelters and an isolation trench during vegetation season (spring to autumn) since 2010. Root samples were collected during autumn in 2010, 2012, and 2013. Root analyses revealed the effect of drought stress on mycorrhizal root tips changed over time. While a density of active mycorrhizae was about 34% lower in drought-stressed areas compared to nonstressed (control) areas in 2010, it increased by 15% in 2012 and by 22% in 2013 over both plots. We observed the less pronounced effect of drought on a proportion of active mycorrhizae, but it generally followed the pattern of active mycorrhizae density. The density of nonactive mycorrhizae was not influenced by drought but significantly fluctuated during the course of the experiment. Other root characteristics such as the dry mass of fine roots (< 1 mm), the specific length of fine roots (< 1 mm) and the composition of the ectomycorrhizal community (primarily dominated by Amphinema byssoides, Tylospora fibrillosa, Tylopilus felleus, and Cenococcum geophilum) were also not significantly influenced by drought. Our results indicate the ability of Norway spruce fine roots to com- pensate for repeated drought stress of the intermediate intensity