Influence of the external environment on the moisture spectrum of Norway spruce (Picea abies (L.) KARST.)

The fluctuation of relative humidity and temperature in the surrounding environments of wood products is an important parameter influencing their mechanical properties. The objective of this study was to investigate the complex relationship between the moisture content and mechanical properties of wood as a critical aspect in the design of durable and reliable structures. Over a period of 669 days, a simulated type of experiment was conducted, during which the moisture content and external temperature were continuously measured in a compact profile of Norway spruce (Picea abies (L.) KARST.). The data were processed using quadratic and cubic models to establish a predictive model. It was found that the quadratic models slightly outperformed the cubic models when considering time lags greater than six days. The final model demonstrated a significant improvement in explaining the variance of the dependent variable compared to the basic model. Based on these findings, it can be concluded that understanding the relationship between the moisture content and temperature of wood samples plays an important role in wood’s efficient use, particularly for timber constructions. This understanding is vital for accurately predicting the mechanical characteristics of wood, which, in turn, contributes to the development of more durable and reliable structures.Web of Science147art. no. 134

Litter leachate as a potential selector of woody species germination at alpine treeline

The advancement of upper forest limits is driven by environmental conditions, but our current understanding overlooks the attributes of habitats and germination ability of woody species. Habitats, through plant litter, impact the competitive relation of germination and seedling growth. The aims of this study were to identify the selective effect of six litter leachates on the germination of indigenous Norway spruce (Picea abies) and nonindigenous dwarf pine (Pinus mugo) and compare the germination rates of the species. We collected plant litter and seeds from the (sub)alpine belt of the Hrubý Jeseník Mts. (the Eastern Sudetes Mts.; the Czech Republic). We evaluated the effect of plant litter leachates from alpine heathlands, wind-swept alpine grasslands, subalpine tall-herb plants, Pinus mugo scrub, subalpine Vaccinium vegetation, and Norway spruce clonal groups on germination process under standard light and temperature conditions. The germination of Norway spruce was inhibited by the litter leachate from subalpine tall-herb vegetation mainly dominated by Calamagrostis villosa, whereas that of dwarf pine was not. The other five litter leachates had no significant effect on the both. Under standard conditions, the germination time of dwarf pine is on average one day faster. These results suggest that most of the litter leachates examined may have small impacts on the germinability and germination time of Norway spruce and dwarf pine, but litter from the subalpine tall-herb vegetation can act as a filter that influences the seedling composition of the woody species.</p

How alpine heathlands response to the snow cover change on the ski slope? Long-lasting ski slope impact case study from the Hrubý Jeseník Mts (Central Europe)

The distribution and duration of snow cover are important variables that affect ecosystem processes in the alpine zone. The establishment of ski resorts dramatically change their surrounding environment and ski slopes represent significant anthropogenic impact in the mountains. We assessed the changes in environmental factors, phenology, growth, and reproductive performance of bilberry (Vaccinium myrtillus), a dominant species of alpine heathlands, caused by a “nature-friendly” managed ski slope (i.e., without artificial snow and machine grading) at permanent plots established on the ski slope under operations (inside the ski slope) and on an unaffected control area (outside the ski slope). A lower mean temperature and a shorter time of great temperature fluctuation during snow melting, a longer time span of snow cover, and a higher snow water equivalent were observed inside the ski slope compared to outside it. Due to changed environmental conditions, the beginning of growth was postponed, and a delay in phenological development was observed in the bilberry at the ski slope. However, bilberry ripened both inside and outside the ski slope in a similar period and showed similar cover and even higher flower and fruit densities inside the ski slope compared with natural surroundings. The persistence of bilberry was not deteriorated and its performance was even better inside the ski slope. On the ski slope, managed snow cover can reduce the potential vegetation shifts due to expected impact of the climate warming. That should be taken into account in conservation and management planning

The Use of Spectral Indices to Recognize Waterlogged Agricultural Land in South Moravia, Czech Republic

The agricultural landscape of the Czech Republic is facing climate change, and drought is among the most severe stress factors. Thousands of small ponds and naturally wet areas have been drained and transformed into agricultural parcels. Their restoration could increase the landscape’s resilience to climate change. Therefore, we describe the possibility of using hyperspectral aerial surveying for the identification of waterlogged areas in the agricultural landscape based on the example of one of the warmest and driest regions of the Czech Republic—the South Moravian region, an area where water retention in the landscape is highly relevant. Within our study, a total of 33 spectral indices related to the waterlogging of soil selected from previous studies were evaluated. The maximum entropy model (MAXENT) was used in the analysis of these indices. The analysis, which was carried out in several locations during different periods of the year (spring and autumn), shows the varying applicability of individual groups of indices. Regardless of the season, chlorophyll-based indices (MCARI—31.8, CARI—26.3, TCARI2—24.3 average percentage contribution) made the most significant contribution to the creation of probability maps of the occurrence of waterlogged areas. However, more accurate results could be achieved in the spring period by using the NVI index (40.5 average percentage contribution). The results show that remote sensing could be used for the identification of waterlogged sites, especially for initial identification, which should then be confirmed by field survey. Furthermore, the research points out the role of the LAI and chlorophyll content. According to the NVI, low LAI contributes the most to the probability of occurrence in the spring season, while chlorophyll-based indices prove to be the best, contributing high values, which is rather contradictory but could be resolved only by subsequent field research

Změny alpinských ekosystémů na území KRNAP‚ NPR Králický Sněžník a CHKO Jeseníky v kontextu globálních změn

Projekt řeší jeden ze základních cílů resortního programu výzkumu v působnosti Ministerstva životního prostředí, kterým je zastavit pokles biologické rozmanitosti. Předmětem zkoumání jsou reakce alpinské vegetace a půdního prostředí pod vlivem globálních změn prostředí. Tato problematika je studována v prostředí alpinské tundry na území chráněné krajinné oblasti Jeseníky, národní přírodní rezervace Králický Sněžník a Krkonošského národního parku. Metodika řešení spočívá v kombinaci několika metodických přístupů tak, aby bylo možné postihnout jak rané, subtilní změny podmínek prostředí tak i jeho středně a dlouhodobé změny pod vlivem globálních změn prostředí. Navržené postupy vychází ze současných scénářů očekávaných změn globálního klimatu, které lze aplikovat na alpinské prostředí sudetských pohoří. Zpráva přináší popis stavu řešení v roce 2007

Vliv rekreačního využití na stav a vývoj biotopů ve vybraných VCHÚ (CHKO Beskydy‚ Krkonošský národní park‚ CHKO Jeseníky a NP a CHKO Šumava)

Obrazové přílohy k závěrečné zprávě tvoří mapy oblastí výskytu rysů, jeřábka lesního, tetřeva hlušce, vlka, medvěda hnědého v CHKO, mapy zátěže turistických tras v letním a zimním období, mapy intenzity zátěže komunikací v letním a zimním období, mapy lyžařských areálů a sídel v CHKO, mapy zimních a letních aktivit a průvodních jevů v CHKO

Vliv rekreačního využití na stav a vývoj biotopů ve vybraných VCHÚ (CHKO Beskydy‚ Krkonošský národní park‚ CHKO Jeseníky a NP a CHKO Šumava)

Tato část závěrečné zprávy přináší shrnutí výsledků řešení jednotlivých tematických okruhů v průběhu realizace projektu (2003 – 2007), vyslovení závěrů a navržení konkrétních doporučení monitoringu a managementu rekreačních aktivit v souladu se zadáním projektu. Ve druhém svazku I. části pokračuje kapitola Zhodnocení dosavadního vlivu rekreačního využívání na dotčené ekosystémy a předměty ochrany na vybraných modelových lokalitách. Zpracování návrhu metod hodnocení a monitoringu vlivů rekreačních aktivit (Shrnutí výsledků za ochranářsky významné druhy živočichů vysokých teritoriálních škál, chemické a hydrobiologické ukazatele povrchových vod, geomorfologické procesy, mikroklimatické charakteristiky, vybrané ekosystémové procesy a návrh metod hodnocení a monitoringu vlivů rekreačních aktivit na přírodní prostředí)