National Repository of Grey Literature 5 records found  Search took 0.01 seconds. 
Processes governing sympatric coexistence of di- and tetraploid cytotypes in primary contact zone of Knautia arvensis agg.
Hanzl, Martin ; Kolář, Filip (advisor) ; Duchoslav, Martin (referee)
Intensive cytotype screening in the primary contact zone of relict serpentine Knautia arvensis agg. revealed a striking predominance of the derivative tetraploid (81 % of subpopulations) over the diploid maternal race. Eleven mixed-ploidy subpopulations with the close spatial proximity of both cytotypes were identified. Flow cytometric analyses of almost 5 000 individuals led to discovery of two extremely rare minority cytotypes (3x, 6x). Vegetation analyses were made at two different spatial scales and in both cases confirmed the absence of distinctions in habitat preferences of cytotypes. Slight microhabitat segregation of cytotypes was however apparent at the finest spatial scales. Cytotype distribution within mixed-ploidy sites was not random. Striking patterns of cytotype clumping into cytotype uniform patches and negative spatial correlations between diploid and tetraploid individuals were apparent at all sites. Distribution of life cycle stages of diploids and tetraploids within the mixed-ploidy subpopulations were significantly different. The clonality was the most common mode of reproduction in the subpopulations of both cytotypes. Seedlings accounted for only 7 % of new plants. Significant distinctions in the plant vigour between the cytotypes were showed during the in situ comparison in...
The Use of Asbestos, Remediation of Contaminated Areas and the Risk of Impact on the Human Organism
Štípek, Radek ; Bendl, Jiří (advisor) ; Mihaljevič, Martin (referee)
The work deals with the uses of asbestos minerals, methods of safe disposal of asbestos and the disease burden caused by exposure to asbestos fibers, of which the most dangerous is crocidolite. Attention is paid to the physical-chemical and structural properties, classification and explanation of the processes of their formation, indicating areas of the Czech Republic and abroad. Describes the history of asbestos use since ancient times to the 20th century, including mass balance asbestos consumed in the technosphere that over the past hundred years, amounts to almost 194 million tons. It then focuses on building fire protection, insulation and other products with different content of asbestos in the world which total over 3000 and registered on the characteristics of asbestos substitute materials, such as ceramic, glass and carbon fibers, aramids, wollastonite, vermiculite and perlite. Describes methods for determination of asbestos fibers in the air, water and soil as a complete course of rehabilitation of contaminated objects. Asbestos fibers pose a risk to human health in the form of asbestosis, first diagnosed in 1900, pleural hyalinosis, lung cancer and mesothelioma of the pleura, where the first evidence of association with exposure to asbestos dates back to 1955 and on the basis of which...
Population dynamics of Minuartia smejkalii
Hrušková, Karolína ; Münzbergová, Zuzana (advisor) ; Dostál, Petr (referee)
Serpentine areas in the Czech Republic form minor but important islands in the landscape with specific chemical properties such as high content of magnesium and other heavy metals. Due to this, serpentine is toxic for most plants. Increased demands on the survival and occurrence of plants lead to the emergence of serpentine specialists obligatorily specialized in these extreme habitats. Currently, serpentine areas are threatened by gradual overgrowth of sites, insufficient or poor site management and fragmentation or shrinkage of sites due to anthropogenic activities. Along with the disappearing localities, the serpentine specialists, are becoming highly endangered. Minuartia smejkalii is highly endangered serpentine specialist with an endemic occurrence in the Czech Republic with great need of its conservation. The aim of the work was to collect data on population dynamics of the species and identify habitat and climatic factors affecting population growth. We studied dynamics in all existing 7 populations during the period from 2006 to 2020 were collected. We linked these data to information on population dynamics, habitat and climatic factors and analysed them using Integral projection models (IPM). The study presents the importance of individual habitat and climatic conditions on the dynamics...
The Use of Asbestos, Remediation of Contaminated Areas and the Risk of Impact on the Human Organism
Štípek, Radek ; Bendl, Jiří (advisor) ; Mihaljevič, Martin (referee)
The work deals with the uses of asbestos minerals, methods of safe disposal of asbestos and the disease burden caused by exposure to asbestos fibers, of which the most dangerous is crocidolite. Attention is paid to the physical-chemical and structural properties, classification and explanation of the processes of their formation, indicating areas of the Czech Republic and abroad. Describes the history of asbestos use since ancient times to the 20th century, including mass balance asbestos consumed in the technosphere that over the past hundred years, amounts to almost 194 million tons. It then focuses on building fire protection, insulation and other products with different content of asbestos in the world which total over 3000 and registered on the characteristics of asbestos substitute materials, such as ceramic, glass and carbon fibers, aramids, wollastonite, vermiculite and perlite. Describes methods for determination of asbestos fibers in the air, water and soil as a complete course of rehabilitation of contaminated objects. Asbestos fibers pose a risk to human health in the form of asbestosis, first diagnosed in 1900, pleural hyalinosis, lung cancer and mesothelioma of the pleura, where the first evidence of association with exposure to asbestos dates back to 1955 and on the basis of which...
Processes governing sympatric coexistence of di- and tetraploid cytotypes in primary contact zone of Knautia arvensis agg.
Hanzl, Martin ; Kolář, Filip (advisor) ; Duchoslav, Martin (referee)
Intensive cytotype screening in the primary contact zone of relict serpentine Knautia arvensis agg. revealed a striking predominance of the derivative tetraploid (81 % of subpopulations) over the diploid maternal race. Eleven mixed-ploidy subpopulations with the close spatial proximity of both cytotypes were identified. Flow cytometric analyses of almost 5 000 individuals led to discovery of two extremely rare minority cytotypes (3x, 6x). Vegetation analyses were made at two different spatial scales and in both cases confirmed the absence of distinctions in habitat preferences of cytotypes. Slight microhabitat segregation of cytotypes was however apparent at the finest spatial scales. Cytotype distribution within mixed-ploidy sites was not random. Striking patterns of cytotype clumping into cytotype uniform patches and negative spatial correlations between diploid and tetraploid individuals were apparent at all sites. Distribution of life cycle stages of diploids and tetraploids within the mixed-ploidy subpopulations were significantly different. The clonality was the most common mode of reproduction in the subpopulations of both cytotypes. Seedlings accounted for only 7 % of new plants. Significant distinctions in the plant vigour between the cytotypes were showed during the in situ comparison in...

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