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Brandýs nad Labem-Stará Boleslav, Czech Republic

Mansfeld V.,Czech University of Life Sciences | Mansfeld V.,Forest Management Institute Brandys Nad Labem
Journal of Forest Science | Year: 2011

The paper analyses the representation of Norway spruce (Picea abies [L.] Karst.) (hereinafter spruce) in relation to different conditions of forest sites. The analysis is based on data from the National Forest Inventory conducted in the Czech Republic in 2001-2004 (hereinafter NFI), stratified according to units of the Forest Site Classification System (Plíva 1971, 2000). Results of the analysis provide a structured image of the current share of spruce. The formerly published information on the natural share of spruce was corroborated and the recommended share of spruce in the target species composition of the spruce management system was analyzed. The analysis documents the applicability of NFI data in the technical discussion concerning the future form of forest ecosystems in the Czech Republic. The results can be used as the groundwork for concrete forest management decision-making and will contribute to the study of the biological diversity of forest ecosystems. Source

Samec P.,Palacky University | Samec P.,Forest Management Institute Brandys Nad Labem | Kucera A.,Mendel University in Brno | Tucek P.,Palacky University
Soil and Water Research | Year: 2014

Fluctuations in forest soil properties were described using a time series analysis of the clay content, the chemical (CaO, MgO, Corg, and Ntot) and physicochemical (pH and base saturation (BS)) soil parameters from 1953 to 2008. The analysis involved the dominant acidic, nutrient-rich, and waterlogged forest ecosystems on the territory of the Bohemian Massif and the Outer Western Carpathians (Czech Republic). Trends in the development of the time series of soil properties were optimized by Gauss-Newton's transformation of the exponential combination of the cyclometric function and Euler's number. Identical functions of regression equations on the fluctuations of nutrients, pH, BS, and Corg indicated parallel trends of soil development in different forest ecosystems. Equations representing identical, predictable patterns in Corg fluctuation indicated the stability of the trend. Differences in temporal patterns of nutrients, pH, and BS in different forest ecosystems indicated the susceptibility of developmental trends to external factors. Different regression equations of fluctuations of soil clay and Ntot indicated the occurrence of permanent differences during the soil development. During the period of 1953-2008, soil pH, BS, and CaO concentration decreased but the content of Corg and Ntot increased. Regression functions indicate that pH and BS of forest soils in the Czech Republic have temporarily increased and the content of Corg and Ntot have decreased during the period 2009-2014. Continuous increase in BS is only sustainable if concurrent with an increase in Corg. Source

Adolt R.,Forest Management Institute Brandys Nad Labem | Habrova H.,Mendel University in Brno | Madera P.,Mendel University in Brno
Trees - Structure and Function | Year: 2012

Unique woodlands of Dracaena cinnabari (DC) are at risk throughout most of their range (Socotra Island, Yemen) as a result of missing regeneration and overmaturity. Effective conservation measures depend on reliable predictions of future population dynamics, which depend on accurate data on current age structure. However, age determination of Dracaena sp. has long been a scientific challenge, because the common method of tree ring counts cannot be applied to this or to most other monocotyledonous trees. In the present study, the indirect method for crown age estimation proposed by Adolt and Pavlis (Trees 18:43-53, 2004) was further developed using a more appropriate statistical technique and an intuitive model formulation. This new technique is based on the relationship between the number of branching orders and the number of flowering events that result from a specific growth pattern. We used logistic regression to directly model annual flowering probability, the reciprocal value of which corresponds to the length of the interval between flowering events. Our methodology was applied to data sets collected at two ecologically distinct sites. In Firmihin, the time between flowering events decreases from 28 years between the first and second event to 10 years between the 25th and 26th event. The length of time between flower events in Skant, however, was estimated to be a constant value of 6. 5 years. We propose the application of generalised mixed-effects models and methods of survey sampling to improve the accuracy of crown age estimation in DC. Our methodology may also be useful for age estimations of other tree species with similar growth patterns, such as Dracaena draco and Aloe dichotoma. © 2012 Springer-Verlag. Source

Rejzek M.,Mendel University in Brno | Svatek M.,Mendel University in Brno | Sebesta J.,Mendel University in Brno | Adolt R.,Forest Management Institute Brandys Nad Labem | And 2 more authors.
Biological Conservation | Year: 2016

Dracaena cinnabari, the dominant endemic tree of Socotra Island (Yemen), is in serious decline. The effect this will have on the island's plant diversity remains unknown. We aimed to identify plants associated with Dracaena understorey and assess the importance of Dracaena for maintaining plant diversity. A total of 272 relevés were sampled in Dracaena understorey and in open sites to record the number of individuals of vascular plants. Species richness and composition were compared between understorey and open sites, and species associated with each of these habitats were identified. Additionally, the effect of canopy closure on species richness and abundance was analysed. We also recorded woody species composition of Dracaena stands and investigated spatial relations between Dracaena and other mature woody plants. Understorey plant species composition differed from open site composition. The former habitat showed higher β-diversity and species richness. Among recorded plants, 15 species were classified as understorey specialists, 6 as open-site specialists, and 23 as generalists. Rare species, especially endemics, were more common in the understorey. Canopy closure had differential effect on species abundances among the species classes. Species richness and total abundance were found to be highest in the understorey, particularly in the case of low-to-intermediate canopy closure where understorey and open-site specialists may co-occur. For mature woody plant species, Dracaena was spatially independent from other woody species at most distances. Our results suggest that the decline of Dracaena may negatively affect plant diversity, reduce abundance of rare endemic plants and lead to homogenization of vegetation. As no other tree species exists in the study area which could replace the Dracaena, our findings underline the importance of conservation efforts to preserve Dracaena stands on Socotra. © 2016 Elsevier Ltd. Source

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