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Jana Škvareninová

Priebeh vegetatívnych fenologických fáz autochtónnych populácií smreka obyčajného (Picea abies [L.] Karst.) zo Slovenska

V príspevku sú zhrnuté výsledky nástupu a priebehu vegetatívnych fenologických fáz 22 pôvodov smreka obyčajného zo Slovenska v rokoch 2006-2008 v podmienkach Arboréta Borová hora v Zvolenskej kotline. Doteraz sa ukázalo, že pôvody do 850 - 950 m n. m. mali takmer rovnaké nástupy fenologických fáz, u pôvodov z vyšších nadmorských výšok sa oneskorujú. Dĺžka jednotlivých fenologických fáz nezávisí od nadmorskej výšky. Začiatok nástupov fenologických fáz v jednotlivých rokoch súvisel s teplotami vzduchu a dĺžkou trvania snehovej pokrývky - najskôr prebiehal v roku 2007 a najneskôr v roku 2006. Možno očakávať, že v budúcnosti budú dreviny na nepôvodných stanovištiach vystavené extrémnym podmienkam, ktoré môžu narušiť ich fyziologické procesy.

Open access

Jana Škvareninová

Priebeh jarných fenologických fáz na generatívnych orgánoch autochtónnych populácií smreka obyčajného (Picea abies [L.] Karst.) zo Slovenska

The results of phenological observations of the generative organs of Norway spruce (Picea abies [L.] Karst.) in the Zvolen Basin are analysed. Twenty autochthonous spruce populations taken from its natural areas of distribution and planted in the Arboretum of Borova Hora belonging to the Technical University of Zvolen present the altitudinal range of 500-1,450 m. The 10% beginnings of phenological stages as a Flower buds swelling, a Formation of flowers before blossom, flowering and blossom fall were observed during the period of 2006-2008. Flower buds swelling occurred on its average from 12th till 21st of April and lasted 9-11 days predominantly. The formation of flowers before blossom occurred from the 23rd of April till the 2nd of May and lasted 5-6 days. The stage of Flowering began on its average from 29th April till 8th May and predominantly lasted 5-6 days. Blossom fall occurred on average from 5th till 17th May and predominantly lasted 11-12 days. The earliest occurrence of phenological stages was recorded in years 2007 and 2008, while a moderate delay in the year of 2006 caused by low temperature and long lasting snow cover. Variation coefficients approached values from 0.57 up to 3.19%. The equalization of air temperature course during the later spring period resulted in the observed decrease of variability of both the Flowering and Blossom fall. The altitude of original sites, the observed provenances come from, has not influenced neither the time of particular phenological stages beginnings nor the lengths of their periods. The conditions of a new environment proved to be decisive.

Open access

Jozef Minďaš and Jana Škvareninová

Abstract

Study of the effects of climate change on upper tree limit has mainly focused on the diversity of tree species as a result of the ability of species to tolerate temperature and moisture changes as well as some effects of disturbance regime changes. The tree species diversity changes due to climate change has been analysed via gap model and biodiversity indices. Gap models are individually based on simulations of establishment, growth, and mortality of each tree on the forest plot. Input ecological data for model calculations have been taken from the permanent research plots located in primeval forests in mountainous regions in Slovakia. The results of regional scenarios of the climatic change for the territory of Slovakia have been used, from which the values according to the CGCM3.1 (global) model, KNMI and MPI (regional) models. Model results for conditions of the climate change scenarios suggest a shift of the upper forest limit to the region of the present subalpine zone, in supramontane zone. The most significant tree species diversity changes have been identified for the upper tree line and current belt of dwarf pine (Pinus mugo) occurrence. Hill’s index of biodiversity in the upper forest line increased by 30 – 35% for horizon of 2050, resp. by 45 – 50% modeled for the horizon of 2075. Calculated values of Shannon’s index show an even higher increase due to climate change. For horizon 2050 is a roughly of three fold increase and horizon for 2075 by almost fivefold increase in the value of the index. Results from the gap model indicate the increase of tree species diversity 2 – 2,5 times.

Open access

Matus Hribik, Tomas Vida, Jaroslav Skvarenina, Jana Skvareninova and Lubomir Ivan

The paper evaluates the results of a 6-year-monitoring of the eco-hydrological influence of Norway spruce (Picea abies (L.) Karst.) and European beech (Fagus silvatica L.) forest stands on the hydro-physical properties of snow cover. The experiment was carried out in the artificially regenerated 20-25-year-old forest stands approaching the pole timber stage in the middle mountain region of the Polana Mts. - Biosphere reserve situated at about 600 m a.s.l. during the period of maximum snow supply in winters of years 2004 - -2009. Forest canopy plays a decisive role at both the snow cover duration and spring snow melting and runoff generation. A spruce stand is the poorest of snow at the beginning of winter. High interception of spruce canopy hampers the throughfall of snow to soil. During the same period, the soil surface of a beech stand accumulates greater amount of snow. However, a spruce stand accumulates snow by creating snow heaps during the periods of maximum snow cumulation and stand´s microclimate slows down snow melting. These processes are in detail discussed in the paper. The forest stands of the whole biosphere reserve slow down to a significant extent both the snow cover melting and the spring runoff of the whole watershed.

Open access

Jana Škvareninová, Mária Tuhárska, Jaroslav Škvarenina, Darina Babálová, Lenka Slobodníková, Branko Slobodník, Hana Středová and Jozef Minďaš

Abstract

Research on urban climates has been an important topic in recent years, given the growing number of city inhabitants and significant influences of climate on health. Nevertheless, far less research has focused on the impacts of light pollution, not only on humans, but also on plants and animals in the landscape. This paper reports a study measuring the intensity of light pollution and its impact on the autumn phenological phases of tree species in the town of Zvolen (Slovakia). The research was carried out at two housing estates and in the central part of the town in the period 2013–2016. The intensity of ambient nocturnal light at 18 measurement points was greater under cloudy weather than in clear weather conditions. Comparison with the ecological standard for Slovakia showed that average night light values in the town centre and in the housing estate with an older type of public lighting, exceeded the threshold value by 5 lux. Two tree species, sycamore maple (Acer pseudoplatanus L.) and staghorn sumac (Rhus typhina L.), demonstrated sensitivity to light pollution. The average onset of the autumn phenophases in the crown parts situated next to the light sources was delayed by 13 to 22 days, and their duration was prolonged by 6 to 9 days. There are three major results: (i) the effects of light pollution on organisms in the urban environment are documented; (ii) the results provide support for a theoretical and practical basis for better urban planning policies to mitigate light pollution effects on organisms; and (iii) some limits of the use of plant phenology as a bioindicator of climate change are presented.

Open access

Zbyšek Šustek, Jaroslav Vido, Jana Škvareninová, Jaroslav Škvarenina and Peter Šurda

Abstract

After the windstorm of November 2004, the ground beetle assemblages (Coleoptera, Carabidae) differentiated after the windstorm into four groups reflecting degree of damaging and forestry management (intact stand, fallen timber in situ, extracted timber, fire). The stand with fallen timber reduced abundances of original species. Removal of timber eliminated sensitive forest species and favored tolerant species, whereas the fire allowed invasions of field species. Later, the assemblages on burned sites converged to those in the unburned sites. Their restoration has a sigmoid-like course. Independently on the above differentiation and course assemblage succession, episodes of severe drought resulted with a 1-2-years delay in sudden decline of number of individuals and species. Their numbers were restoring after longer humid periods. Because these extremes occur with a considerable regularity, the observed extremes of fluctuations of number of species and individuals represent the variability limits of the Carabid assemblages in such conditions. The Standardized Precipitation Evapotranspiration Index was shown, using the cross-correlation of SPEI and number of individuals and species of Carabids, as a suitable means to explain and predict such changes for the period of 1-2 years.