|
|
Impact of warming on soil organic carbon
Štecová, Michaela ; Vindušková, Olga (advisor) ; Jílková, Veronika (referee)
Climate change is the main cause of rising global temperatures around the world. Carbon sequestration in terrestrial ecosystems is considered one of the main tools for climate change mitigation, but current estimates of sequestration potential do not include the impacts of future climate change. The aim of this thesis is to summarize our current knowledge on the response of soil organic carbon to warming, alone as well as in combination with other drivers of climate change. A complementary aim is to compare the different methods used to study the impact of warming on soiIncreased temperature causes significant losses of soil carbon, but no consistent effect has been observed in combination with other aspects of climate change. Research suggests that carbon losses depend on the stability of soil fractions, with warming leading to greater decreases in particulate organic matter (POM). The combination of warming with rising CO2 concentration has led to an overall increase in soil carbon, although losses have been observed in combination with drought. When studying the effects of warming on soil carbon stocks, selecting the appropriate method is crucial. Active methods offer precise control but are more expensive and can impact soil biota, whereas passive methods are cheaper but require more time....
|
|
|
Priming efekt a jeho vliv na chování spotřebitele
Hřebíčková, Michaela
The diploma thesis deals with the priming effect and its influence on consumer behavior. The priming effect is referred to as an experimental framework showing that the processing of a previously identified stimulus affects how we react to a later identified stimulus, at a subconscious level. This work consists of a theoretical part and an analytical part, which includes an overview of the current state of e-commerce in the Czech Republic and the results of foreign studies on the influence of the priming effect, as well as an analysis of primary data obtained through questionnaire surveys and in-depth interviews. The results of the primary data analysis show that consumers are influenced by some kinds of priming effect. Based on these findings, a recommendation was proposed for companies on how they can use these types of priming effect in their marketing campaigns.
|
|
|
Priming effects and its relation to accumulation of soil organic matter during succession
Galertová, Renata ; Frouz, Jan (advisor) ; Cajthaml, Tomáš (referee)
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...
|
|
|
Vliv kořenových exudátů na dekompozici rozpuštěné organické hmoty v rašeliništi
ŽAMPACH, Ondřej
The aim of this thesis was to assess the effect of root exudates on the biodegradability of dissolved organic matter. The experiment was done in laboratory conditions, using the dissolved organic matter sampled in a spruce swamp forest located in Šumava National Park and an artificial mixture of root exudates prepared according to known composition of root exudates released by peatland plants. Main hypothesis was that the input of root exudates into the peatland pore water will affect decomposition of less-degradable dissolved organic matter, with the resulting effect dependent on the quantity and quality (C:N ratio) of the input.
|
|
|
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...
|
guest ::
