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Tool to assess the landscape connectivity in different area units and dispersal distances
Chrumko, Adam ; Šímová, Petra (advisor) ; Krčílková, Šárka (referee)
The purpose of this diploma thesis is to introduce a basic summary of landscape connectivity calculations mainly focusing on the Conefor program and the effect of input parameters on output landscape connectivity indices. One of the main goals is to create an ArcMap Toolbox to simplify the calculation of landscape connectivity indices for many areas of interest. Basic squares that cover the whole Czech Republic were chosen as main areas of interest. These units are used for example for mapping the abundance of flora and fauna. The same indices were calculated for NUTS3 and LAU1 areas in order to compare effect of size of input areas. This thesis provides a simple solution in the form of a Python Toolbox for Esri ArcMap to calculate overall indices of landscape connectivity through a Conefor command line application for a large number of input areas. Forest connectivity for different dispersal distances and input areas of interest was calculated with this Toolbox. As an input vector layer of forests, CORINE land cover data from mapping period 1990, 2000, 2006 and 2012 were used. Input dispersal distances were chosen in the range from 50 to 50.000 meters in order to comprehensively describe their effects on indices. Resultant forest and connectivity changes are represented by cartograms; the effect of input data on output indices is shown in graphs.

Comparison of forest stands on afforested agricultural vs. continuously forested soil
Květoň, David ; Podrázský, Vilém (advisor) ; Jiří, Jiří (referee)
There are many differences between environment of woodlands on afforested agricultural lands and continuously forested soils. These differences are able to persist for many years after afforestation. It is anticipated differences in the growth and condition of these stands. This thesis deals with these differences and aims to compare them. There were compare differences between spruce stands and larch stands and differences between thickness of overlying humus in four plots of the size 0,25 ha, in the area laying near to village Brložec, in region of Karlovy Vary. Results moreless confirm a greater production of both species of trees on former agricultural lands, they indicate greater production potential of larch compared with spruce and they clearly show thicker humus to continuously forested areas.

Evaluation of soil variability based on measuring the soil electrical conductivity.
Votavová, Eliška ; Kroulík, Milan (advisor) ; Novák, Petr (referee)
The aim of this diploma thesis was to verify the new capabilities for mapping variability of soil using measurement platforms mounted on machines for tillage. The chapter Soil describes types of soil in the Czech Republic, the causes of soil variability and the methods of spatial interpolation. The chapter Mapping Spatial Variability of Land focuses on the method of determining the variability of soil properties through direct and indirect methods, selection of locations for collection of soil samples, methods of measuring electrical conductivity and an overview of options for mapping, mainly via on-the-go sensors. The last part of the literary research is entitled Geographic Information System where I have described the purpose and uses of this system in precise farming. The subsequent practical part of the diploma thesis focuses on evaluation of the level of variability of farm land based on measuring of soil conductivity via a galvanic contact method of measuring and its subsequent comparison during use of an EM 38 MK2 soil conductivity probe. The conclusion contains a summary of the thesis and evaluation of the level of agreement between the obtained data files.

Construction and scientific implementation of mathematical models for tree compartments of broadleaved trees in growth stages of seedlings and young stand
Pajtík, Jozef ; Konopka, Bohdan (advisor) ; Monika, Monika (referee)
Importance of precise estimation for tree biomass in forests has been continuously increasing. Regarding to the climate change, scientists have started to quantify all tree components not only in terms of energetic utilization but also for carbon stock estimation. Increasing relevance of biomass models for young trees relates to expanding area of young forest stands during the last period due to decay of old forests often caused by disturbances (especially: windstorms, outbreaks of bark beetles, drought episodes, and forest fires). Models for biomass stock estimations constructed for stands with age to 10 years are rare and usually are focused on aboveground tree parts. Thus, this work aims at filling knowledge gaps in this field. Its main objectives are: 1) construction of regression models applicable for estimation of dry mass in the particular tree components (i.e. stem, branches, foliage, roots) for young stands of some broadleaved species, 2) implementation of regression models for calculation of biomass conversion and expansion factors (BCEF), allocation coefficient, growth efficiency and leaf area index (LAI) and their inter-specific comparison, 3) utilisation of allometric relations for estimation on forage potential for ruminating ungulate game (i.e. browsing and stripping). To make up the models, destructive tree sampling will be implemented. The sample trees will be excavated, separated into tree components, dried for constant weight and weighed. Log-transformed relationships will be used for construction of regression models.

The Effect of Oregano Essential Oil on Microbial Load, Drying Kinetics and Sensory Atributes of Dried Meat
Hernandez Hernandez, Helga Johana ; Banout, Jan (advisor) ; František, František (referee)
Microbial load can be controlled using either synthetic or natural preservatives. Particular interest has been focused on the potential application of plant essential oils as safer additives for meat. However, there is no published research on the use of essential oils during the meat drying process. This study was focused on enhancing the meat drying process. At first a value-added dried meat product by using oregano essential oil (OEO) to inhibit the growth of bacteria, and the sensorial response from assessors is presented. It was found that the application of the OEO in meat is effective in inhibiting Salmonella enteritidis and Escherichia coli. After 6 hours of drying at 55°C, 2 ml (0.038 ml l-1 air) and 1.5 ml (0.028 ml l-1 air) of OEO were considered the minimal inhibitory concentrations (MICs) against S. enteritidis and E. coli, respectively. Samples treated with 0.75 ml of OEO were more attractive for consumption compared with the control; at a higher concentration of OEO, the sensory quality of the food was affected. Next, the effect of modified blanching treatments on the drying behaviour of beef meat was evaluated by determining moisture ratio versus time curves and the influence on sensory quality of the resulted product. The 3 treatments under investigation were (1) oil treatment (2) steam blanching and (3) hot air blanching with 3 doses of oregano essential oil (1) 1.5 ml (2) 3 ml and (3) 6 ml. Each treatment had an effect on the drying time of the beef samples, however, the dose of oregano essential oil applied did not affect the drying process. The results showed that steam blanching was very effective reducing the drying time. Meanwhile, 1.5 ml and 3 ml hot air blanching samples and 1.5 ml oil treatment samples were judged as better from sensory point of view and the respondents considered that adding oregano essential oil enriched the pleasantness of the smell. In conclusion, a value-added dried meat product obtained by using oregano essential oil to enhance food safety received an acceptable sensorial response from consumers. Additionally, each modified blanching treatment tested influences the drying kinetics process, but the dose of oregano applied did not affect the drying process. In this sense, hot air blanching and oil treatment with the lowest dose had an acceptable sensorial response from consumers.

Biotransfer of selected risk metals into plants and their accumulation and distribution in plant organs
Le Minh, Phuong ; Lachman, Jaromír (advisor)
Contamination of soils with heavy metals is one of the serious environmental problems threatening human being. Heavy metals are considered as the special hazard of soil pollutants because of the adverse effects on the plant growth, the amount, activity of useful microorganisms in soils and the quality of food. Regard to the persistent and toxicity, the heavy metals are toxic when we consider different kinds of pollutants in soils. In the soil, zinc (Zn), cadmium (Cd), lead (Pb) and mercury (Hg) toxicities frequently occur than the other metals because of their precipitation and sorption by the soil. It is a very dangerous situation because when these metals are taken up by plants, they can be transported to the food web and food chains. In the present study, the accumulation of four heavy metals (mercury, zinc, lead and cadmium) in the whole grain of spring accessions of emmer, einkorn and common spring wheat cultivars and potato (Solanum tuberosum) is reported. Heavy and essential elements were monitored in potato cultivars in the exact field experiments and in hydroponically grown plants. The elements were determined by methods FAAS, ET AAS, and AMA (Advance Mercury Analysis). Statistical analyses were performed using SPSS 9.0 with the Tukey HSD (Honestly Significant Difference) test (alpha equal to 0.05). In our study, the concentration of heavy metals decreased in the order zinc (Zn) > lead (Pb) > cadmium (Cd) > mercury (Hg) in the wheat grain. The comparison between three varieties of investigated wheat revealed that the emmer wheat was rich in zinc content (62.12 mg kg-1 dry matter), while the spring wheat had the lowest average concentration of zinc in the grain (40.99 mg kg-1 dry matter). Generally, the values of lead concentration in grain wheat varieties were low (ranging from 0.1268 mg kg-1 dry matter to 0.2950 mg kg-1 dry matter). The concentrations of mercury in four typical growth stages of wheat (boot stage 10, heading stage 10.2 1/4 of head emerged, leaf-stage 10.2 and stage ripening 11 according to Feekes) were also determined. It has been shown that the concentrations of mercury in different wheat varieties were absorbed differently at different growth stages of plant. Stage 10.2 and leaf stage 10.2 showed the high mercury content (0.0152 mg kg-1 dry matter and 0.0214 mg kg-1 dry matter, respectively). Among individual varieties significant differences were determined. Amounts of toxic and potentially toxic elements detected in investigated potato tubers are characterized by a large variability within investigated groups. Performing statistical analysis (one way ANOVA) showed that there were no significant differences between two investigated groups of samples (samples from Uhříněves and Valečov in the year 2013 and 2014) considering either one of investigated metals. Measurable levels of mercury were found in smallest amounts in all investigated potato samples comparing to other metals (Cd, Pb). Plant cells compared to animal cells are characterized by the formation of cell walls. Plasma membrane or cell membrane is a biological active membrane separating the interior of cell from the outside environment. An adjusted method for isolation of protoplasts was developed and adapted for isolation of protoplasts from plant material (potatoes). In our experiment, the plants were grown hydroponically in the Research Institute of Plant Crops Prague-Ruzyně. If we examine the plant membrane, one option is to remove the cell wall by means of special mixture enzymes. Protoplasts were released in the dark at 25 degrees of Celsius for 18 hours. The 70 and 90 microns sieve was used to filter and then centrifugation for 5 minutes at 100 x g. All the steps were carefully carried out to prevent the damage or breakage of protoplasts.

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.

Diagnotics of the important apple viruses
Winkowska, Lucie ; Ryšánek, Pavel (advisor) ; Petr, Petr (referee)
Apple mosaic virus (ApMV), Apple stem grooving virus (ASGV), Apple stem pitting virus (ASPV) and Apple chlorotic leaf spot virus (ACLSV) are economically the most important viruses in pome fruit trees, which are distributed worldwide and can caused significantly yield reduction. The major control strategies (namely pathogen detection, exclusion by crop certification or quarantine, control in infected orchards by eradication from infected cultivars and rootstocks, etc.) rely heavily on accurate and sensitive detection methods and on perfect knowledge of pathogens. In the doctoral thesis the diagnostic method quantitative RT-PCR (qRT-PCR) was optimized for detection and quantification of four studied viruses. The results suggested that qRT-PCR method was the most reliable technique in comparison with conventional diagnostic methods DAS/I-ELISA and RT-PCR. In our study the concentration of ASGV, ASPV and ACLSV, measured by qRT-PCR, were stable during vegetation and in different plant tissue. Only the concentration of ApMV changed during vegetation in leaves and inner bark. This result indicates that changes of virus concentration observed by DAS/I-ELISA and RT-PCR in plant tissues are caused by other way (inhibitors, plant senescence, lower sensitivity, ect.) than by changes of virus concentrations in plant. Under the monitoring (at all 351 trees were tested) it was showed, that studied viruses were more spread in orchards and gardens then in wild apple trees. Selected virus isolates from wild apple trees and apples from orchards and gardens were sequenced and molecular variability was studied also with already published isolates. However individual isolates of studied viruses were similar. The variability associated with geographic origin or with type of planting has not been confirmed.

Growth and environmental effects of Grand fir cultivation in conditions of the Czech republic
Fulín, Martin ; Podrázský, Vilém (advisor) ; Antonín, Antonín (referee)
Grand fir (Abies grandis /Douglas ex D. Don/ Lindl.) is a species with potential benefits for the implementation of many functions in forest management: namely the function of production, soil improvement, stabilization and landscaping. It was introduced to the Czech Republic, as well as to other European countries, since the first half of the 19th century, mainly by aristocratic families. First plantings were performed in the parks, but gradually also in the forest stands. Another wave of interest in this tree species was associated with the decline of the domestic silver fir (Abies alba Mill.). It was to some extent substitute, for this period comes the greatest number of plantations in the country. The aim of this thesis is, therefore, monitoring of growth and production of the grand fir, but also the evaluation of the effects on the basic characteristics of the soil chemistry, nutrient dynamics and possible degradation effect on forest lands. Research areas were mainly located in the University Forest Enterprise Kostelec nad Černými lesy, but also in other places such as Hrubá Skála at Turnov, forests owned by Kinský at Žďár nad Sázavou and Kynšperk nad Ohří. Monitoring was carried out on already established and monitored middle-aged permanent plots (35 to 55 years), which were assessed at mensurational parameters (position, height, diameter at breast height, ratio of the green crown), in further the quantity and quality of forest floor and upper mineral soil components was studied. This work also contains the measurements of the provenance plot of Forestry and Game Management Research Institute. The results show that the grand fir is a productive tree species that exceeds the stock of domestic conifer tree species and its intensive growth is comparable with Douglas fir. From the perspective of provenance trials is crucial the correct choice of provenance, which achieves better yields and quality of wood. Best provenances come from the island Vancouver and the coast of Washington state. At the soil analysis reaching grand fir better values in comparison with Norway spruce and got it closer to the values of broad-leaved tree species. Thus it can be said that grand fir represents important soil-improving and stabilization tree species.

Utilization of biological and chemical amelioration treatments for restoration of anthropogenic degraded locality near Boleboř village in Ore Mts.
Kouba, Martin ; Podrázský, Vilém (advisor)
This dissertation contains evaluation of the growth dynamics and nutritional status of tree species plantations after application of biological and chemical amelioration treatments, impact of trees on quality of soil and on the accumulation of surface humus. There were evaluated: Norway spruce (Picea abies L.), Blue spruce (Picea pungens Engelm.), Birch (Betula spp.), European larch (Larix decidua Mill.), Gray alder (Alnus incana Moench.), Lodgepole pine (Pinus contorta Dougl.), Eastern White pine (Pinus strobus L.) and Rowan (Sorbus aucuparia L.). On 4 research plots in Boleboř (Ore Mts.) was measured height, thickness of root collar, breast-height diameter. Were taken samples of soil, weed and assimilation apparatus. There was determined yellowing, browsing, plants mortality and calculated amount of accumulated surface humus. Application of fertilizer Silvamix Forte on spreading windrows reduced mortality and increased increment for the first 3 years, the effect is evident even after 10 years. It was not confirmed the attractiveness of plants for wildlife after Silvamix Forte application. Silvamix Mg fertilizer application had minimal effect on the growth dynamics and nutrient contents in needles. Positively impacted soil characteristics, increased the value of the cation exchange capacity, decrease in hydrolytic acidity, increase the saturation of sorption bases, decrease of aluminium ions Al3+ and decrease of Fe2O3. On fertilized plots increased content of available nitrogen, phosphorus, calcium and magnesium, increase of the total supply of nitrogen, calcium and magnesium. The rapid increase in the content of Ca and Mg is related to the liming in 2002. Fertilizer application significantly supported the development of ground-weed on plots of Colorado blue spruce mixed with birch, while in pure stands of Colorado blue spruce led to a reduction in aboveground biomass. For the Colorado blue spruce mixed with birch plot compared with only Colorado blue spruce plot were documented favourable soil properties, increased supply of total nitrogen, phosphorus and potassium. Rowan tree on an intact soil surface exhibits the lowest reaction pH as humus and in the mineral, high hydrolytic acidity, extremely sorption unsaturated soil state, high content of ion Al3+ and low content of available calcium, although was applied liming. Technical and biological reclamation (Boleboř III.) has a long-term positive effect on the average height and breast-height diameter of Colorado blue spruce and white pine. The growth dynamics of European larch and Lodgepole pine were affect only at the beginning. Meliorated stand of Gray Alder has very good growth dynamics, comparable with Larch and Lodgepole pine. The big problem is the game impact, especially in Lodgepole pine, which led to the destruction of all individuals. Colorado Blue spruce in terms of biological reclamation is totally inappropriate. This Spruce has reduced resistance to abiotic factors, which often suffer uprooting and breakage. During the 21 years the Clorado Blue spruce mixed with birch accumulated of 66,09 t.ha-1 humus matter with better properties also in the deeper horizon. Colorado Blue spruce accumulated 54,11 t.ha-1 of humus matter. Rowan tree accumulated on the intact soil largest amount of humus matter (194,98 t.ha-1), however acidifies the deeper horizons. The stand of Norway Spruce occurred during the reporting period a decrease of 47% to 107,03 t.ha-1. The decline may be associated with more open stand and due to air liming.