Christina Kaiser

Christina Kaiser
University of Vienna | UniWien · Microbiology and Ecosystem Science

PhD

About

65
Publications
21,987
Reads
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3,862
Citations
Citations since 2016
30 Research Items
3046 Citations
20162017201820192020202120220200400600
20162017201820192020202120220200400600
20162017201820192020202120220200400600
20162017201820192020202120220200400600
Additional affiliations
December 2011 - January 2014
International Institute for Applied Systems Analysis
Position
  • PostDoc Position
January 2011 - December 2011
University of Western Australia
Position
  • PostDoc Position

Publications

Publications (65)
Article
Full-text available
Plant roots release recent photosynthates into the rhizosphere, accelerating decomposition of organic matter by saprotrophic soil microbes ("rhizosphere priming effect") which consequently increases nutrient availability for plants. However, about 90% of all higher plant species are mycorrhizal, transferring a significant fraction of their photosyn...
Article
Full-text available
Soil microorganisms control carbon losses from soils to the atmosphere1–3, yet their responses to climate warming are often short-lived and unpredictable4–7. Two mechanisms, microbial acclimation and substrate depletion, have been proposed to explain temporary warming effects on soil microbial activity8–10. However, empirical support for either mec...
Article
Full-text available
The chemical structure of organic matter has been shown to be only marginally important for its decomposability by microorganisms. The question of why organic matter does accumulate in the face of powerful microbial degraders is thus key for understanding terrestrial carbon and nitrogen cycling. Here we demonstrate, based on an individual-based mic...
Article
Full-text available
Under the current paradigm, organic matter decomposition and nutrient cycling rates are a function of the imbalance between substrate and microbial biomass stoichiometry. Challenging this view, we demonstrate that in an individual-based model, microbial community dynamics alter relative C and N limitation during litter decomposition, leading to a s...
Article
Full-text available
Plants rapidly release photoassimilated carbon (C) to the soil via direct root exudation and associated mycorrhizal fungi, with both pathways promoting plant nutrient availability. This study aimed to explore these pathways from the root's vascular bundle to soil microbial communities. Using nanoscale secondary ion mass spectrometry (NanoSIMS) ima...
Article
Full-text available
Ectomycorrhizal fungi live in close association with their host plants and form complex interactions with bacterial/archaeal communities in soil. We investigated whether abundant or rare ectomycorrhizal fungi on root-tips of young beech trees (Fagus sylvatica) shape bacterial/archaeal communities. We sequenced 16S rRNA genes and fungal internal tra...
Article
Plant roots release a variety of low-molecular weight compounds, such as sugars, amino acids or organic acids into the soil, impacting microbial activities and physico-chemical soil processes in their surroundings. These compounds are a source of easily available C and energy for soil microbes, potentially accelerating microbial decomposition of so...
Conference Paper
Full-text available
Arbuscular mycorrhizal fungi (AMF) form obligate mutualistic associations with the roots of most plant families, providing nutrients for their host plants and receiving carbon in return. Soil nutrient availability is known to affect AMF abundance and community composition. For example, excessive phosphorus (P) fertilization decreases AM fungal root...
Article
Network analysis has been used for many years in ecological research to analyze organismal associations, for example in food webs, plant-plant or plant-animal interactions. Although network analysis is widely applied in microbial ecology, only recently has it entered the realms of soil microbial ecology, shown by a rapid rise in studies applying co...
Preprint
Full-text available
Network analysis has been used for many years in ecological research to analyze organismal associations, for example in food webs, plant-plant or plant-animal interactions. Although network analysis is widely applied in microbial ecology, only recently has it entered the realms of soil microbial ecology, shown by a rapid rise in studies applying co...
Article
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Depolymerization of high-molecular weight organic nitrogen (N) represents the major bottleneck of soil N cycling and yet is poorly understood compared to the subsequent inorganic N processes. Given the importance of organic N cycling and the rise of global change, we investigated the responses of soil protein depolymerization and microbial amino ac...
Article
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Ectomycorrhizal plants trade plant-assimilated carbon for soil nutrients with their fungal partners. The underlying mechanisms are, however, not fully understood. Here we investigated the exchange of carbon for nitrogen in the ectomycorrhizal symbiosis of Fagus Sylvatica across different spatial scales from the root-system to the cellular scale. We...
Article
Full-text available
Microbial community analysis via marker gene amplicon sequencing has become a routine method in the field of soil research. In this perspective, we discuss technical challenges and limitations of amplicon sequencing and present statistical and experimental approaches that can help addressing the spatio-temporal complexity of soil and the high diver...
Article
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Article
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Soil organic carbon management has the potential to aid climate change mitigation through drawdown of atmospheric carbon dioxide. To be effective, such management must account for processes influencing carbon storage and re-emission at different space and time scales. Achieving this requires a conceptual advance in our understanding to link carbon...
Article
Full-text available
Elevated CO2 (eCO2) experiments provide critical information to quantify the effects of rising CO2 on vegetation1–6. Many eCO2 experiments suggest that nutrient limitations modulate the local magnitude of the eCO2 effect on plant biomass1,3,5, but the global extent of these limitations has not been empirically quantified, complicating projections o...
Article
Full-text available
Root exudation is an important process determining plant interactions with the soil environment. Many studies have linked this process to soil nutrient mobilization. Yet, it remains unresolved how exudation is controlled and how exactly and under what circumstances plants benefit from exudation. The majority of root exudates including primary metab...
Article
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In the version of this Letter originally published, the name of the institute in affiliation 3 was incorrect; it read “Institute of Applied Systems Analysis” but should have read “International Institute for Applied Systems Analysis”. This has now been corrected.
Article
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Root surfaces are major sites of interactions between plants and associated microorganisms. Here, plants and microbes communicate via signaling molecules, compete for nutrients, and release substrates that may have beneficial or harmful effects on each other. Whilst the body of knowledge on the abundance and diversity of microbial communities at ro...
Conference Paper
Full-text available
Plants deliver recently assimilated carbon (C) to mycorrhizal fungi, and receive nutrients, such as N and P, in exchange. A reciprocal exchange of C and nutrients between plants and mycorrhizal fungi (i.e., fungi which deliver more nutrients receive more plant C in return and vice versa) has been suggested for arbuscular mycorrhizal symbioses by so...
Article
Large rainfall events following drought cause pulses of CO2 flux that are higher than models predict. This phenomenon, named the “Birch effect” after its discoverer, has been observed for decades, and will in- fluence carbon-climate feedbacks as dryingerewetting (DRW) cycles become more common under intensified climates. Yet, the many interacting f...
Data
Supplementary Figures 1-3, Supplementary Tables 1-2, Supplementary Methods and Supplementary References.
Data
Spatio-temporal dynamics of microbial decomposers and cheaters during a model run - Visualisation of spatio-temporal dynamics of microbial decomposers, cheaters and organic matter during a model run (simulating a 1 mm2 area of decomposing leaf litter). All panels represent the same grid of 100 x 100 microsites (each microsite is 10x10x10 μm). The l...
Data
Full-text available
Fig. S1Experimental set up. Fig. S2Light micrograph of a transverse section through an immature wheat root (Triticum aestivum). Fig. S3Correspondence analysis (CA) based on C concentration and concentration of excess 13C of phospho- and neutral lipid fatty acid biomarkers extracted from soil associated with wheat (Triticum aestivum) roots or associ...
Article
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Permafrost-affected soils in the Northern latitudes store huge amounts of organic carbon (OC) that is prone to microbial degradation and subsequent release of greenhouse gases to the atmosphere. In Greenland, the consequences of permafrost thaw have only recently been addressed, and predictions on its impact on the carbon budget are thus still high...
Article
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Turbic Cryosols (permafrost soils characterized by cryoturbation, i.e., by mixing of soil layers due to freezing and thawing) are widespread across the Arctic, and contain large amounts of poorly decomposed organic material buried in the subsoil. This cryoturbated organic matter exhibits retarded decomposition compared to organic material in the to...
Article
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There is growing evidence of a direct relationship between microbial community composition and function, which implies that distinct microbial communities vary in their functional properties. This study aimed at elucidating whether differences in initial substrate utilization between distinct microbial communities are due to activities of certain m...
Conference Paper
Background/Question/Methods Rainfall patterns are expected to intensify in the future. Microbial responses to the resulting fluctuations in soil moisture could influence pulses of carbon dioxide that have been observed after extreme rainfall events, which many ecosystem models currently underestimate. So far, it has been difficult to determine th...
Article
Full-text available
Substrate quality and the availability of nutrients are major factors controlling microbial decomposition processes in soils. Seasonal alteration in resource availability, which is driven by plants via belowground C allocation, nutrient uptake and litter fall, also exerts effects on soil microbial community composition. Here we investigate if seaso...
Conference Paper
Full-text available
The release of carbon through plant roots to the soil has been recognized as a governing factor for soil microbial community composition and decomposition processes, constituting an important control for ecosystem biogeochemical cycles. Moreover, there is increasing awareness that the flux of recently assimilated carbon from plants to the soil may...
Article
Full-text available
Soil microbes in temperate forest ecosystems are able to cycle several hundreds of kilograms of N per hectare per year and are therefore of paramount importance for N retention. Belowground C allocation by trees is an important driver of seasonal microbial dynamics and may thus directly affect N transformation processes over the course of the year....
Article
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Plant roots strongly influence C and N availability in the rhizosphere via rhizodeposition and uptake of nutrients. This study aimed at investigating the effect of resource availability on microbial processes and community structure in the rhizosphere. We analyzed C and N availability, as well as microbial processes and microbial community composit...
Article
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The UNECE-ICP Integrated Monitoring site Zöbelboden in the Northern Alps of Austriawas established to assess the effects of air pollutants on forest ecosystems. Changes in recruitment of the dominant tree species may be among these effects but there is little information on how germination and juvenile growth of these species respond to changes in...
Article
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Integrating microbial physiology and biomass stoichiometry opens far-reaching possibilities for linking microbial dynamics to ecosystem processes. For example, the growth-rate hypothesis (GRH) predicts positive correlations among growth rate, RNA content, and biomass phosphorus (P) content. Such relationships have been used to infer patterns of mic...
Article
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It was hypothesized that seasonality and resource availability altered through tree girdling were major determinants of the phylogenetic composition of the archaeal and bacterial community in a temperate beech forest soil. During a 2-year field experiment, involving girdling of beech trees to intercept the transfer of easily available carbon (C) fr...
Article
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The phospholipid fatty acid biomarkers 18:1ω9, 18:2ω6,9 and 18:3ω3,6,9 are commonly used as fungal biomarkers in soils. They have, however, also been found to occur in plant tissues, such as roots. Thus, the use of these PLFAs as fungal biomarkers in sieved soil, which may still contain small remains of roots, has been questioned. We used data from...
Article
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Plant seasonal cycles alter carbon (C) and nitrogen (N) availability for soil microbes, which may affect microbial community composition and thus feed back on microbial decomposition of soil organic material and plant N availability. The temporal dynamics of these plant–soil interactions are, however, unclear. Here, we experimentally manipulated t...
Article
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The integrated modelling of coupled socio-ecological systems in land-change science requires innovative model concepts capable of grasping the interrelations between socioeconomic and natural components. Here, we discuss the integrated socio-ecological model SERD (Simulation of Ecological Compatibility of Regional Development) that was developed fo...
Article
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The aim of this study was to assess initial effects of warming on the CO2 balance of a lichen-rich dwarf shrub tundra, a widespread but little studied ecosystem type in the Arctic. We analyzed whole ecosystem carbon exchange rates as well as nutrient dynamics, microbial and plant community composition and biomass after 2years of experimental temper...
Article
Cryoturbation (mixing of soil layers due to repeated freeze-thaw processes) is a major soil forming process in arctic regions, which may contribute to long-term storage of C in soils of northern latitudes. Our goal was to determine the effect of subduction of organic matter by cryoturbation on microbial decomposition processes in tundra soils. Buri...
Article
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An 1800-km South to North transect (N 53°43′ to 69°43′) through Western Siberia was established to study the interaction of nitrogen and carbon cycles. The transect comprised all major vegetation zones from steppe, through taiga to tundra and corresponded to a natural temperature gradient of 9.5°C mean annual temperature (MAT). In order to elucidat...