Gewählte Doctoral Thesis:
Evi Deltedesco
(2020):
Interactive effects of warming, elevated CO2 and weather extremes on nitrogen fluxes and underlying microbial processes.
Doctoral Thesis - Institut für Bodenforschung (IBF),
BOKU-Universität für Bodenkultur,
pp 146.
UB BOKU
obvsg
Data Source: ZID Abstracts
- Abstract:
- Climate projections for the next decades predict a significant increase in air temperature, atmospheric CO2 concentrations and frequency and intensity of extreme weather events. While the impact of individual environmental factors on biogeochemical processes and soil microbial community structure and function are relatively well studied, there are only few studies that have investigated the combined effect of several changes. Such changes are surface warming, elevated atmospheric CO2 and extreme weather events, like severe droughts followed by short and heavy rainstorms. This PhD thesis targeted this knowledge gap and addressed as first simultaneously individual and combined climate change factors with varying levels of surface warming and atmospheric CO2 fumigation along with a drought-rewetting experiment. Effects on trace gas emissions, soil microbial structure and function as well as mineral and organic N dynamics in soil were tested at the experimental field site Climgrass at the Agricultural Research and Education Centre in Raumberg-Gumpenstein.
Results of this PhD thesis show that multifactorial field experiments are of crucial importance to identify complex effects of climate change. Essentially, all experiments of this thesis pointed to the overarching importance of soil water content. The soil water balance is affected by air temperature and atmospheric CO2 as well as changes in precipitation. This, in turn, influences plant physiology and vegetation, microbial community composition and function and consequently soil microbial processes and GHG emissions. Due to the complexity of the interactions between several environmental factors (warming, elevated CO2 and extreme events) indirect effects tended to be stronger than direct effects.
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Betreuer:
Zechmeister-Boltenstern Sophie
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1. Berater:
Keiblinger Katharina
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2. Berater: