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Vliv vybraných agrotechnických faktorů na stav půdní organické hmoty při dlouhodobém pěstování jarního ječmene
Šanderová, Pavla
The aim of the thesis is to make an evaluation of the impact of agro-technical factors (tillage, crop rotation), in the total amount of oxidizable carbon Cox (%) on a long-term grown spring barley. Measurements were carried out in 2014 and 2015, excluding these years from long series of observations. It is a stationary experiment in sugar beet growing region which runs continuously since 1989. The experiment has been established by Mendel University in Brno - Ivanovice in Hana on the cultivated land owned by Crop Research Institute, v. v. i. In Prague - Ruzyně. The observations were made in two rotations with 33.3% and 66.6% share of cereals. There were compared four variants of the tillage and samples were taken from three depths. The Cox monitored impacts were statistically demonstrated in all the variables (crop rotation, tillage and sampling depth). There was also found higher concentration of Cox in the crop rotation with 66.6% cereals representation. While tillage monitoring, the highest amount of Cox was seen by use of tillage equipment in the extent of 0,10 metres. On the other hand, the lowest amount of Cox was found by direct seeding into a soil. Also, it was found that the amount of Cox decreases with depth of sampling in both monitored years.
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Comparison of soil microbial activity on sites with different forest management practices
Volánek, Jiří
Presented thesis is focused on microbial activity of forest soils and aims at characterizing some of its parameters on sites with different silvicultural management practices. Coppice, coppice-with-standard and high forest stands were compared in terms of carbon and nitrogen content, content of microbial biomass, enzymatic activity and selected physical properties of soil. Study was conducted between September 2015 and April 2016 on pre-existing TARMAG II research plot near Soběšice, Brno, Czech Republic. Samples were collected during three different calendar seasons, allowing for seasonal dynamicity assessment of the studied parameters. Statistical evaluation detected significant effect of management type on potential respiration of studied soil samples as well as significant effect of seasonality on microbial biomass content in incubated samples, phosphatase activity in fresh soil samples, catalase activity in both fresh and incubated samples and potential respiration of studied samples. Results also show that the overall potential activity of urease and catalase was at its highest during the winter season.
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Phytodiversity in old fields of different age and management history on agricultural land adjacent to Czech villages in Romanian Banat area
Veselý, Adam ; Kovář, Pavel (advisor) ; Tichý, Tomáš (referee)
The main aim of this thesis was to identify the main factors influencing development and diversity of vegetation on old fields around village Svatá Helena in Romania. I evaluated the influence of age of an old field, its management (mowing, pasture, burning and fallowing), soil chemical properties, topography and surrounding vegetation. Using phytosociological relevés I collected data about species composition and coverage of species of the old field vegetation. With the assistance of local inhabitants I found out the age of the old fields and the type of applied management. I performed chemical analysis of soil properties, determined amount of available phosphorus, total carbon and nitrogen and pH. I also performed floristic survey of surrounding vegetation. The data showed a unimodal trend in plant diversity during succession. The maximal diversity was recorded on 12 years old old fields. The diversity was also influenced by C/N ratio of soils. Growing C/N ratio had a negative effect on plant diversity. Analysis also showed some interesting connections between soil properties and topographic factors. Organic C and N in soils were rising with age of old field, rate of accumulation is higher on slopes. The results showed that soil chemical properties have the highest influence on species...
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Impact of litter quality on decomposition
Vicena, Jakub ; Frouz, Jan (advisor) ; Cajthaml, Tomáš (referee)
The text of the thesis is divided into two parts. The literature overview discusses the importance of decomposition to carbon cycling in soils and evaluation of biological, physical and chemical factors that affect decomposition. To understand the factors affecting the soil respiration is essential to improve the global carbon balance. Decomposition affects also the release of nutrients, soil fertility and other soil processes and properties. The very project aims at the impact of leaf litter quality assessment (specifically, the C: N: P ratio) on the rate of decomposition. The assumption is that the low C:N ratio initially accelerates the decomposition which quickly reaches its minimum. Conversely, at a high C: N ratio the rate of decomposition is initially slower and subsequently reaches its minimum, and the average value of decomposition will be higher than in samples with low C:N ratio. For litter which has undergone leaching phase none of the significant differences in respiration of the individual samples with different C:N were statistically proved.
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Soil chemical and microbial properties in reclaimed and unreclaimed grasslands
Čížková, Barbora ; Frouz, Jan (advisor) ; Cepáková, Šárka (referee)
For successful restoration of unstable ecosystems in the dumps recreating a fully functioning lan dis needed. Dump substrates often have poor grain composition, extreme pH or are toxic. They also lack important recent organic matter, which improves the overall quality of the soil and is therefore necessary for the development of quality and fertile soil. Therefore, restoration of ecosystems in the dumps is initially very slow. A number of reclamation measures was invented to accelerate this process - for example, heaping up of topsoil to dump substrates. With organic matter present in the topsoil soil formation is faster and often with their physical and chemical properties differ significantly from then developed soils. There has already been number of works written considering development of soils on the Velká podkrušnohorská výsypka so far, none of which, however, did not affect grasslands. The aim of this work was to obtain complete information about the development of chemical and microbial properties of soils that were recultivted by reclaimed topsoil and grassed and then to compare them with developments in the areas of overgrown spontaneous succession. It was found that the total carbon content increases with time only in the reclaimed areas and maximum of the increase is in the depth of...
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Soil organic matter accumulation and humification during pedogenesis
Inogamova, Malika ; Frouz, Jan (advisor) ; Bartuška, Martin (referee)
Soil is comprised of minerals, SOM , water, and air. Soil development is caused by climate and living matter acting upon parent material (weathered mineral or organic matter from which the soil develops), as conditioned by topography, over time. SOM is a dynamic component of the soils system. Plant productivity is effected by the SOM. SOM provide nutrients and habitat to the organisms living in the soil, including plants, roots and SOM also binds soil particles into aggregates and improves the water holding capacity of soil. SOM is a product of biological decomposition that affects the chemical and physical properties of the soil and its overall fertility. Humus is only partly metabolized by soil organisms but improves the physical and chemical properties of soil. It consists of different humic substances: fulvic acid, humic acid, and humin. Soil is a solid material that results from the interaction of weathering and biological activity on the parent material or underlying hard rock. The fundamental pedogenic processes, used also as a criterion for classifying soils, is associated with SOM accumulation. We discuss the nature and interrelations of the SOM humification and accumulation processes during pedogenesis and the environmental factors on pedogenic processes influencing the rate of SOM...
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Fyzikální frakcionace půdní organické hmoty
KREJČÍKOVÁ, Jitka
The aim of this study was to review the literature about aggregate formation and role of soil organic matter in aggregate stability. Further aim was to introduce method of physical fractionation and use it for the practical part. The chosen method was used and tested on mineral soils from watersheds of Čertovo and Plešné Lakes.
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Comparison of two methods of soil organic matter fractionantion
Fryčová, Kateřina ; Frouz, Jan (advisor) ; Borůvka, Luboš (referee)
Comparison of two different soil organic matter fractionation methods Soil organic matter (SOM) significantly affects physical, chemical and biological properties of soils and plays also a crucial role in the global carbon cycle. In order to simulate SOM dynamics a number of mathematical models have been developed. These models divide SOM into several theoretical pools according to their stability. Unfortunately, lacking experimental procedure which could measure these pools directly, although for this purpose a wide range of fractionation procedures were developed, that are trying identified empirical fractions with theoretical model pools. An objective of this experiment was to reproduce two fractionation procedures on a set of twenty-seven laboratory-prepared samples: according to Six and according to Zimmermann and to compare their results. Also the relationship between respiration and the amount of carbon in different pools was compared. The most significant differences were found in active pools, where Six's method found twice as much carbon than Zimmermann's one. Finally response of both method results to various environmental parameters (mineral composition, litter type and soil mixing) was compared. According to the results of Zimmermann's method the amount of carbon in different pools was mainly...
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Priming effects and its relation to accumulation of soil organic matter during succession
Galertová, Renata ; Cajthaml, Tomáš (referee) ; Frouz, Jan (advisor)
Priming effects are fast short-term changes in the turnover of soil organic matter (SOM). Depending on sources of released CO2, priming effects are classified as real (acceleration of mineralization SOM) or apparent (release of CO2 due to accelerated microbial biomass turnover). Mechanisms causing priming effects remain poorly understood. Microbial competition, nitrogen limitation, microbial diversity changes, effect of living roots are the most often mentioned among mechanisms that cause priming effect. In my thesis I have studied intensity of priming effects in soil from post mining heap that vary in age and SOM content. These soils were affected by addition of substrates with different complexity (glucose, starch and cellulose) in two levels. Addition of 0.2 ml 1.75 % glucose, starch and cellulose solution resulted in statistically significant increase in CO2 release only in one soil. Addition of 0.8 ml 1.75 % glucose, starch and cellulose solution cause significant increase in released CO2 in 3 from 5 soils. Causes of these changes are not clear however in some cases it exceed level of added C could mean real priming effects connected to release already stored C. In soils where organic matter was accumulated on the soil surface and is not mixed into soil was observed the most strong priming...
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