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Effect of water deficit on the energy content of individual plant organs in selected species of leafy vegetables
Šimůnková, Petra ; Hnilička, František (advisor) ; Česká, Jana (referee)
This work presents the impact of water deficit on dry mass production and photosynthetic accumulation of energy on every single plant´s organs of selected plant species. As a chosen experimental material were taken plants of Spinacea oleracea "Matador" sort and Tetragonia tetragonioides.
Spinacea oleracea and Tetragonia tetragonioides plants were grown in containers 11x11cm large in mixture of garden substrate A with silicon sand (2:1) in 2 variations placed in FAPPZ greenhouses. One variation was for control and second was exposed to stress reaction. Control variation had been watered for whole time of experiment with 50ml of water 2 times per week. Stressed one had been watered after puncturing and 6. taking until the end of experiment.
During the plant´s ontogenetic evolution had been monitored dry mass´s weight on singular plant´s organs. With usage of burnt calorimetry method had been monitored capacity of photosynteticaly accumulated energy in dry mass. Quantity of netto energy had been found out by dry burning adiabatic calorimeter LAGEST MS 10A.
From the gained results emerge, that plants of Tetragonia tetragonioides have 2 times higher weight growth apart from Spinacea oleracea. Control plants of Tetragonia tetragonioides have higher weight by 25,5% (123 mg) compared to the plants growing in water deficit. Likewise higher weight of roots had been observed on control plants (41 mg) compared to the stressed plants (40 g). Control spinach plants had higher weight of above-ground biomass by 19,5% compared to the stressed ones (43 mg). Roots of control plants had lower weight compared to stressed variant by 2960 mg.
From the results emerge, that plants of Tetragonia tetragonioides have higher weight of roots dry mass and above-ground biomass compared to the Spinacea oleracea plants.
Burning heat without ashes was on above-ground biomass of control plants Tetragonia tetragonioide on 15,96 kJ.g-1 level and on stressed plants 14,93 kJ.g-1 . In case of Spinacea oleracea plants was amount of control plants energy 14,98 kJ.g-1 and on stressed 14,21 kJ.g-1.
Burnt heat without root ashes of Tetragonia tetragonioides control plants was higher by 1.11 kJ.g-1 then on stressed ones (13,19 kJ.g-1). In case of Spinacea oleracea plants was amount of roots energy on control plants 11,90 kJ.g-1 and on stressed 11,72 kJ.g-1 .
Based on measurement were verified differences between species in reaction on water deficit and observed characteristic. From measuring emerged, that Spinacea oleracea plants are more sensitive on effect of water deficit compared to the Tetragonia tetragonioides
plants, which is more tolerant. Next thing observed is, that there are differences in amount of dry mass and rate of burnt heat in relation on effect of water deficit.
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Use of Festuca arundinacea for decorative lawns
Doskočil, Jan ; Svobodová, Miluše (advisor) ; Hrevušová, Zuzana (referee)
Use of Festuca arundinacea for decorative lawns
Summary
Festuca arundinacea is briefly bentgrass with broader and coarser leaves. Hardly perennial grass, native to Europe, is well known for its high resistance of dry weather, low intensity of maintenance and resistance of high use. These qualities gains thanks to its well-developed and deep root system, which is capable to gain water and nutrients from deeper parts of soil. Its use is in places with high use, like a race-course, edges of roads or vineyards alleyway. Today, in time of global warming, its usage becomes more important for park purposes and low-input turfs, where is its higher resistance against biotic and abiotic stresses, mainly against drought, utilized. Festuca arundinacea complement well with Poa pratensis in turf.
Goal of this work was to evaluate turfs with Festuca arundinacea and chosen grass species under different mowing frequency. According to hypothesis frequency shouldn´t affect turf coverage. Coverage should be same with different mixture composition with Festuca arundinacea.
The experiment was performed on experimental land of Czech university of Life Sciences Prague, Suchdol in 2015. Mixtures of Festuca arundinacea with Festuca rubra, Poa pratensis and Lolium perenne were seeded together with monocultures of these species in 2012. Mixture composition was 50/50 except mixture of Fesruca arundinacea and Poa pratensis, where the mixture was 75/25. There were conducted 63 plots, in 3 repetitions and in 3 different frequencies of mowing (by 14, 30 and 45 days). Each plot was 6 m2 big. The results were evaluated by analysis of variance ANOVA (P is smaller than 0.05) in program Statgraphics, version XV.
Influence of mixture composition to level of growth was significant. The highest level of growth has monoculture of Festuca arundinacea (10,6 cm). The lowest level of growth has monoculture of Lolium perenne (5,4 cm). Monoculture of Festuca arundinacea had the highest intensity of grow (0,07 cm/day) at 14-day frequency of moving. Lolium perenne has the lowest intensity of grow (0,02 cm/day). At 30-day frequency of mowing mixture of Festuca arundinacea with Poa pratensis has the highest intensity of grow (0,24 cm/day). The lowest intensity of grow has Lolium perenne (0,01 cm/day). The highest intensity of grow was at 45-day mowing frequency. The highest intensity of grow has mixture of Festuca arundinacea with Festuca rubra (0,75 cm/day). The lowest intensity of grow has monoculture of Lolium perenne (0,06 cm/day). Influence of mixture composition to coverage was statistically significant. The highest coverage has mixture of Festuca arundinace with Festuca rubra (81,3 %). The lowest coverage has monoculture of Lolium perenne (58,6%). Influence of frequency to level of growth was statistically significant. The highest level of growth has 45-day frequency of mowing (6 cm) and the lowest level of growth has 14-day frequency of mowing (3,8 cm). Influence of frequency to coverage was statistically significant. The highest coverage 14-day frequency of moving (76,5 %) and the lowest has 45-day frequency of growing (66,7 %).
The knowledge gained will be used for further compilation grass mixtures for park lawns. It turned out that it is better to prefer seeding mixtures with Festuca arundinacea than monocultures. To achieve high coverage and optimal intensity of growth with Festuca arundinacea was recommended to follow 30-day frequency of mowing.
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Performance recording in Charolais beef herd
Jelínek, Petr ; Toušová, Renata (advisor) ; Petr, Petr (referee)
Summary
In this thesis I dealt with verification of performance of beef cattle Charolais Breed on farm: Chov Charolais spol. s r. o. Slabce. The main objective of my diploma work was to assess the growth abilities of calves Charolais breed from birth till weaning in relation to various factors, for instance: gender, order of calving, number of born calves during one calving, month and year of the birth on the respective farm. The relevant data was assessed for the period of years 2012 - 2015. In this period there was born 324 calves of which 162 bulls, 153 heifers and 9 still born calves. The assessment of calf's growth characteristics was related to the average birthweight, average gain from birth to 120 days, and average weight at the age of 120 and 210 days. For the evaluation of calf's growth characteristics was used data gained from the database of performance testing of beef cattle (KUMP) for the given period. Growth parameters related to selected factors were processed with the use of statistical software SAS 9.3 (SAS 9.3, 2011).
The average weight of young bulls at birth was 33,58 kg and average weight of heifers was 32,99 kg. The average weight of bulls at the age of 120 days was 183,66 kg and the average weight of heifers was 175,58 kg which was demonstrated to be statistically significant (P < 0,01). The average weight of bulls at the age of 210 days was 288,28 kg which is again higher than heifers with average weight of 264,21 kg (P < 0,05). To summarize, there was identified statistically significant difference of the gender influence in behalf of bulls.
After comparison of average weight at birth, at the age of 120 and 210 days separately for twins and an only child, there is obvious and also statistically significant finding (P < 0,01) that the observed twins are usually smaller at birth and their growth abilities are worse than that of only child. The average weight at birth for an only child is about 4,48 kg higher compared to twins. Then the average weight at the age of 120 days for an only child is about 38,68 kg higher than average weight of twings. Finally the average weight at the age of 210 days is about 58,26 kg higher for an only child.
Regarding to the influence of order of calving there was identified no significant effect to both average birth weight and weight at the age of 210 days. The only statistical significance was identified between order of calving and the average weight at the age of 120 days in 1st, 2nd, 5th, 7th, 10th order of calving (P < 0,05). Further I found out that calves in the 1st order of calving have significantly lower average weight from the 1st calving mothers at the age of 120 days than the calves in the 2nd, 5th, 7th, 10th order of calving. The average weight of calves at the age of 120 days is about 9,29 kg lower than weight of calves in the 2nd order of calving. On the other hand the average weight of calves at the age of 120 days in the 5th order of calving is about 18,37 kg higher than weight of calves in the 1st order of calving. Similarly, calves in the 7th order of calving have about 13,63 kg higher weight than calves from the 1st calving mothers. And also calves at the age of 120 days in the 10th order of calving have about 15,78 kg higher weight than calves from the 1st calving mothers.
In respect of influence of year of birth was identified statistically significant different level (P < 0,01) of the average birthweight in year 2013 compared to other years. Similarly there was demonstrated the statistically significant difference (P < 0,01) regarding to the average gain from birth in year 2013 compared to other years. The average birthweight in 2013 was 34,91 kg. The lowest average birthweight of 31,65 kg was observed in 2015. And for instance in 2012 the average birthweight was 32,48 kg which is still about 2,43 kg lower than in 2013. Regarding the evaluation of the average gain from birth till the age of 120 days there was only reported value of 1046,78 g in 2013. The best year regarding the average gain from birth till the age of 120 days was year 2014 which represented value of 1214,37 g.
In the observed breed there took place births predominantly from January till June. Regarding the month of birth there was demonstrated statistically significant difference (P < 0,05) in respect of average birthweight of calves born in May 31,98 kg compared calves born in February 32,55 kg and in March 33,07 kg. Further was identified statistically significant difference regarding the average gain from birth for calves born in June 995,28 g compared to calves born in February 1197,87 g (P < 0,01). Similarly in March was reported value of 1181,18 g (P < 0,05). The last statistically significant difference (P < 0,01) was identified in respect of average weight at the age of 210 days of calves born in May 199,55 kg and in June 201 kg in comparison to calves born in January 282,05 kg, in February 284,65 kg, in March 277,21 kg and in April 277,76 kg. To conclude, based on the statistical analysis, conclusive results and literary sources there had been confirmed hypothesis that internal factors positively affect the growth abilities of calves.
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Evaluation of growth and fertility in chosen columnar apple-tree varieties
Brázdová, Ludmila ; Zíka, Lukáš (advisor) ; Súkeníková, Tereza (referee)
This paper deals with the evaluation of growth and fertility in selected apple varieties. I will discuss the range of columnar apple trees, which represent a further step in the development of growing shapes. Eleven different varieties grafted onto two different rootstocks was assessed. Planting was establish in the spring of 2013, the clamp 3 x 0,8 m. The trees were planted as a two-year vaccinees.
The aim of the study was to evaluate and compare the increase in trunk diameter, the intensity of growth and yield of selected columnar apple varieties, before and after the end of their vegetation. It was necessary to evaluate the cross-sectional area strain in (cm2), increase in cross-sectional area strain in (cm2), average fruit weight (g), crown height (m), absolute yield (kg) per tree, specific yield on (cm2) cross-sectional area, yield (kg) on increase in area strain, area yield (t / ha) and specific yield on the crown height (kg / m).
In the theoretical part I will deal with the history of apple growing and growing development of various shapes, characteristics of apple trees, their significance and composition. Further I will discuss demands on the growing the apple tree and its treating. At the same time I will mention the major diseases and pests. At the end of this part I will describe harvesting methods and proper storage.
The practical part is focused on the experiment itself and its subsequent evaluation. I will mention the location and characteristics of the habitat where the apple tree grew. I will describe specific columnar varieties and rootstocks used. I will characterize the specific location of the varieties grown and the activities that were implemented during the evaluation period of the experiment.
In conclusion, the results have been evaluated, to which I arrived during the entire measurements. This part contains the observed values displayed in two tables. For a better overview of the data obtained and the results they are displayed graphically. At the end there is a complete summary of the whole work.
For the most of the results it has been proved that a base affects the intensity of growth and yield. The biggest growth area strain (cm2) had a variety 'Cumulus' on rootstock M 26, but on the rootstock M 9 the increase was significantly lower. When assessing absolute yield the highest values were observed in a variety 'Red Spring' on rootstock M 26, followed by the yield of variety 'Slendera' on rootstock M 26. The lowest yield was observed in cultivar 'Cumulus' on M 9. In these cases, we can confirm the influence of rootstock of variety. When evaluating the specific yield on increase strain the highest yield was at varieties 'Red Spring' on M 26, followed by a variety 'Slendera', where the yield was greater on the rootstock M 9. Here it is impossible to unequivocally confirm that the rootstock M 26 has a higher yield than the rootstock M 9.
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Product and process innovation in the company Aveflor, a.s.
Váchová, Lenka ; Štůsek, Jaromír (advisor) ; Ladislav , Ladislav (referee)
The thesis deals with product and process innovation issues in the company Aveflor, a.s. Contemporarily, product and process innovation in a very important issue for a constant new development of services, technological processes and final products in order to keep the pace of the company with the very high competition in the present market. The thesis deals with the innovation process and its particular steps. All the processes are analytically applied on the company Aveflor, a.s.
In the empirical part of the thesis the company Aveflor, a.s. is introduced by analysis of particular phases of innovation process such as: task, development, plan of new products, results of proposals, verification, the realization of a new product, barriers of innovation activities with particular innovations of presented products. The hypothesis is that the whole process of innovation can be improved together with the higher productivity in the company Aveflor, a.s.
The aim of the thesis is to evaluate ongoing innovations of the development of new products in the company Aveflor, a.s. An inherent aim is to compare particular processes, identify drawbacks and make a proposal of their improvements.
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Antimicrobial activity of extract from GRAS plant species agains oral pathogenic microorganisms
Pilná, Jindřiška ; Kokoška, Ladislav (advisor) ; Jaroslav, Jaroslav (referee)
Microbial oral diseases such as caries and periodontitis are among the most frequent human infections. Conventional chemical antiseptics used for their treatment and prevention often produce adverse side-effects, which restrict their long-term use. Although plants are considered as perspective sources of novel antimicrobial compounds, little is still known about their inhibitory properties against oral pathogens and about their safety while used on a daily basis. The objective of this study was to investigate in vitro growth-inhibitory effects of ethanol Generally Recognised as Safe (GRAS) plant and supercritical CO2 hop extracts on planktonic cultures of cariogenic, periodontal and candidal human pathogens, namely Aggregatibacter actinomycetemcomitans, Bifidobacterium dentium, B. longum, Candida albicans, Eikenella corrodens, Fusobacterium nucleatum subsp. vincentii, Lactobacillus salivarius subsp. salivarius, Porphyromonas gingivalis, Streptococcus mutans, S. salivarius subsp. salivarius and S. sobrinus using the broth microdilution method. The findings showed that ethanol extracts of all 109 GRAS plant species inhibited the growth of at least one microorganism under study with minimum inhibitory concentration (MIC) equal or lower than 4096 ug/mL. However, only six of them possessed very interesting antiseptic potential against the oral pathogens with MIC < 100 ug/mL. Additionally, three GRAS plant species showed good inhibitory activity with MIC = 128 ug/mL. As far as the particular results are concerned, the best antiseptic effect was observed for both Humulus lupulus CO2 supercritical and ethanol extracts that inhibited the growth of all microorganisms at MICs higher or equal to 8 ug/mL and MICs higher or equal to 16 ug/mL, respectively. Hence, the CO2 supercritical extraction proved to be superior for extraction of active constituents of H. lupulus. Further, the ethanol extracts of Capsicum annuum and C. frutescens showed significant antiseptic potential against S. sobrinus and S. salivarius (MICs from 64 to 128 ug/mL). The oral streptococci were also inhibited by Zanthoxylum clava-herculis (MIC higher or equal to 64 ug/mL), Helichrysum angustifolium and Myristica fragrans (MIC higher or equal to 128 ug/mL) which further showed the antimicrobial activity against F. nucleatum (MIC = 64 ug/mL). Interesting inhibitory effects exhibited an extract of Punica granatum against C. albicans (MIC = 128 ug/mL) and F. nucleatum (MIC = 64 ug/mL). Moreover, the growth of F. nucleatum was inhibited by extracts of Pimenta officinalis and Thea sinensis (MIC = 128 ug/mL). The chemical analysis of the CO2 supercritical H. lupulus extracts revealed that alpha and beta bitter acids represented the two major groups of constituents. Cohumulone was the predominant compound of the alpha acids, whereas colupulone was the prevalent constituent of the beta acids. Our results suggest that the six GRAS plant species, namely C. annuum, C. frutescens, H. lupulus, M. fragrans, P. granatum and Z. clava-herculis have good potential to become new safe antiseptic agents that might be used for incorporation into oral care products such as toothpastes and mouthrinses.
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Mophological and molecular diversity of a tropical tree species Guazuma crinita in the Peruvian Amazon
Tuisima Coral, Lady Laura ; Lojka, Bohdan (advisor) ; Helena, Helena (referee)
Fast growing tree species Guazuma crinita (Malvaceae) was selected as a priority species for domestication in the Peruvian Amazon due its important contribution to the livelihood of local farmers. Its domestication process is still in an early age as for many tropical tree species little is known about its genetic variability and we dont know anything about the impact of domestication on its genetic resources. The main objective of this research was to assess the genetic variability of G. crinita within and among populations in the Peruvian Amazon by the use of morphological (wood physical traits) and molecular (ISSR and AFLP) markers.
Wood physical properties among six G. crinita provenances were evaluated. Wood samples were drilled from the base middle and top of the stem of 12 randomly selected eight-years-old trees for determination of wood measurement. Pearson correlations between physical properties were also determined. All wood physical properties except green density differed significantly among provenances. We also found statistically significant variation due to stem level position. The moderately dense wood and the coefficient of anisotropy (1.6) suggested that G. crinita has stable wood; they represent important advantages in terms of costs for transport and transformation process. The results suggested potential to select provenances with desirable wood properties for further breeding and domestication. Due to the variation found even in limited tree samples it is recommended further analysis with more extensive number of samples from different provenances and planting zones.
This research presents the first assessment of genetic variability based on inter-simple sequence repeat (ISSR) markers for 44 G. crinita genotypes from a clonal garden multiplication established in the Peruvian Amazon Research Institute (IIAP) in Ucayali region. Ten ISSR primers amplified a total of 65 bands of which 61 were polymorphic (93.8%). The range of DNA amplification varied from 260 to 2200 bp. Among the provenances overall genetic differentiation (Gst) was 0.03 indicating 97% of genetic diversity within provenances. Gene flow (Nm) was 12.9 alleles per generation. Cluster analysis was not related with geographic origin suggesting a common gene pool which was supported by calculation of weak positive correlation was found between genetic and geographic distance.
With the use of AFLP markers an insight on how domestication process does impact G. crinita genetic resources is also reported on this research work. I was able to generate fingerprint for 58 leaf samples representing eight provenances and three population types, 19 from a natural regenerated population 15 cultivated in home garden nursery and 24 from a collection of genotypes considered as semi-domesticated population. Seven selective AFLP primer combinations were used. A total of 171 fragments were amplified with 99.42% of polymorphism at species level. Each type of population generated fragments with 72.51% 49.12% and 54.39% of polymorphic fragments respectively. Neis genetic diversity and Shannon index information were found to be higher in the population of natural regeneration compared to overall semi-domesticated population (He = 0.10 and 0.9; I = 0.19 and 0.16 respectively). The analysis of molecular variation (AMOVA) showed higher variation within provenances rather than among (84% and 4% respectively). UPGMA clusters analysis and PCoA did not showed correspondence between genetic and geographic distance in addition their correlation was not significant. There was a significant genetic differentiation among types of population suggesting slight genetic bottleneck in semi-domesticated populations yet with relatively high levels of genetic variation.
In situ conservation for populations with high levels of genetic diversity was recommended. In addition proper management of natural regeneration and ex situ genotype collections might be a good conservation strategy to maintain G. crinita genetic resources.
The use of morphological (wood physical traits) and molecular markers were successful to reveal genetic variability of G. crinita and they could be used for other tropical tree species. For further researches it is emphasis to extent the number of samples and geographic scale.
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Using Weather Generators for the Assessment of the Impact of Climate Change in Catchments
Martínková, Marta ; Hanel, Martin (advisor) ; Máca, Petr (referee)
The main objective of this dissertation is to provide a novel approach to downscaling of outputs from regional climate models and to simulation of future climate. The resulting method consists of rain generator that operates in 6-hour time step. The generator performs well for the observational data.
It consists of following steps: disaggregation of 6-hour cumulative precipitation into convective and stratiform types, fitting of first order 3-state discrete time Markov chain to the data and simulation of long time series of precipitation. Then the mixture of log-normal and Generalized Pareto distribution is fitted to stratiform events and the Generalized extreme value distribution is fitted to convective events.
The impact of climate change on precipitation is evaluated by using change factors that are identified for precipitation occurrence (by comparing the transition matrices for the future and control period) and for precipitation amount (by comparing the scale and location parameters of distributions fitted for the future and control period). The observational data are then altered with obtained change factors.
From evaluation of observational data it stems that the average volume of an convective event is higher for the western region than for eastern region of the Czech Republic. Additionally, statistically significant trends in number and volume of convective events were identified for the region.
The relative portion of convective precipitation is the highest in summer for observational data.
From analysis of RCMs simulations, it stems that even though the overall precipitation is projected to be lower in future, the proportion of convective events (versus stratiform ones) would be higher. The number of convective events is projected to be lower in the future, while the volume of a convective event to be bigger.
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The effect of housing system on egg shell quality and egg internal quality
Vlčková, Jana ; Tůmová, Eva (advisor) ; Skřivanová, Eva (referee)
In the study 3 experiments were carried out. The objective of the first experiment was to evaluate performance of laying hens, quality of air in poultry house, and microbial contamination of the eggshell in laying hens kept under blue, green, red, and yellow light colour in enriched cages. The laying performance characteristics (hen-day egg production, mortality, and egg weight) were not affected by light colour. Similarly, microbial contamination of the air was not significantly different related to the light colour. There were significant interactions in eggshell contamination between cage floor and light colour in Escherichia coli and Enterococcus. The highest number of Escherichia coli was detected in eggs from hens housed in the middle floor given yellow light and the lowest values on the upper floor also under yellow light colour. Similar results were observed in Enterococcus. The results of our study indicate that the light colour has a minor effect on microbial contamination but the significant influence was in the floor position. The highest microbial egg contamination was found on eggs from the middle floor.
In the second experiment, the effect of housing system (conventional cage, litter, aviary) and feed calcium content (3,0 and 3,5%) on laying performance characteristics, technological quality of eggs, microbial contamination of the eggshell and egg content during storage was evaluated. The significant interaction between housing system and feed calcium content was found in egg weight, eggshell strength, eggshell percentage, eggshell weight, Haugh units and albumen index. The housing system affected egg production, feed intake, egg weight and some characteristics of eggshell quality. From characteristics of eggshell quality the feed calcium content affected only eggshell strength and eggshell percentage. The significant interaction between housing system and storage time was found in contamination of eggshell by total number of microorganisms. The housing system affected also contamination of the eggshell where higher number of Escherichia coli and total number of microorganisms were in eggs from litter. Higher penetration of all monitored species of microorganisms on the eggshell membranes was 2nd and 7th day of storage in the group with 3.5% of calcium in the feed mixture in eggs from the litter. This could be associated with lower quality of eggshell in this type of housing.
In the experiment 3, the effect of different housing system (enriched cage, free range) on technological quality of eggs, microbial contamination of the eggshell, egg content and concentration of protein in albumen during storage was observed. The housing system affected all characteristics of eggshell quality with higher values in cage system. Higher number of pores in eggshell was found in free range. The important relationship between housing system and storage time was indicated in Haugh unit, albumen index, pH albumen and yolk index. The values for characteristics quality of albumen and yolk were better in eggs from cages. Their quality during storage decreased faster in alternative housing systems. There was detected interaction between housing system and storage time also in Escherichia coli, Enterococcus and total number of microorganisms. The highest microbial contamination in fresh eggs was found in free range. The number of microorganisms with storage time significantly decreased faster in eggs from cage system. The penetration of Escherichia coli and total number of microorganisms in albumen was lower in eggs from cage compared to free range. The significant effect of housing system was found in concentration of lysozyme in albumen with higher values in egg from free range. It is obvious that a better quality of the eggs is in the cage housing system. The eggs from this type of housing also remain during storage for longer time in better quality compared with alternative housing systems.
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Dynamics of mountain spruce forest focused on natural regenaration development
Červenka, Jaroslav ; Svoboda, Miroslav (advisor) ; Tomáš, Tomáš (referee)
Disturbances have a major impact on the dynamic of forest ecosystems. However, there is lack of its exact consequences for mountain spruce forests in Central Europe. In 2007 heavy windstorm damaged a lot of stands in Šumava NP, subsequent bark beetle outbreak resulted in a large-scale dieback of spruce stands in this area. We took advantage of this opportunity. This study is focused on disintegration and structure of stands after the severe disturbance and in next step is focused on density and structure of natural regeneration in these stands. In addition we dealt with spruce regeneration (Picea Abies (L.) Karst.) on decaying logs. We compared two localities, disturbed (NP Šumava) and undisturbed site (CHKO Jeseníky). We concentrated on the change in saplings densities and on impact of decaying logs characteristic on this change. Finally we wanted to determinate impact of decaying logs characteristic on density of spruce regeneration. In area of Trojmezná we recorded 99 % mortality of parent stands. We founded only a few of adult tress which survived the disturbance, in addition we found several new trees, most of them with diameter about 10 cm. Live trees (DBH > 7 cm) reach density 16 trees per ha. The amount of dead wood was 2.5 times higher than before 10 years, one third were lying logs. Only natural regeneration of Norway spruce and rowan (Sorbus acuparia L.) was founded. Regeneration recruitments occurred in sufficient numbers, mostly on mosses (32 %), dead wood (27 %) and the nearest neighbourhoods of living mature trees or snags (28 %). Advance regeneration occupied 88 % of all regeneration. The density of individuals was similar along the elevation gradient. But in lower elevation of study area was situated higher regeneration recruitment then in the higher parts. With increasing elevation gradient regeneration was more homogenous in height and was lower. Best conditions for spruce regeneration provides logs with the largest diameters and logs with presence of white fungi Armillaria spp. or Phellinus nigrolimitatus. On the other hand logs with presence of Fomitopsis pinicola do not provide a suitable microsite for saplings. When we compare change in regeneration density on dead wood between the disturbed and undisturbed site, our results show significant increase in regeneration density at disturbed site (by 33 %). The increased regeneration density observed at the disturbed site was mostly associated with the smallest saplings on logs with the largest diameters. Three years after death of the parent stands no significant effect was recorded on the growth rate and survival of established spruce saplings on dead wood.
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