A5022663869- Geology and Paleoclimatology Research
- Isotope Analysis in Ecology
- Plant Water Relations and Carbon Dynamics
- Plant responses to elevated CO2
- Coastal wetland ecosystem dynamics
- Marine and coastal ecosystems
- Tree-ring climate responses
- Atmospheric chemistry and aerosols
- Plant responses to water stress
- Pacific and Southeast Asian Studies
- Aquatic Ecosystems and Phytoplankton Dynamics
- Soil Carbon and Nitrogen Dynamics
- Aquaculture Nutrition and Growth
- Microbial Community Ecology and Physiology
- Metabolomics and Mass Spectrometry Studies
- Hydrology and Watershed Management Studies
- Plant Ecology and Soil Science
- Groundwater and Isotope Geochemistry
- Fire effects on ecosystems
- Plant biochemistry and biosynthesis
- Plant and animal studies
- Agriculture Sustainability and Environmental Impact
- Odor and Emission Control Technologies
- Hydrocarbon exploration and reservoir analysis
- Archaeology and ancient environmental studies
University of Basel
2022-2024
Swiss Federal Institute of Aquatic Science and Technology
2015-2024
University of Freiburg
2020-2024
ETH Zurich
2017-2022
Research Management (Norway)
2022
University of Washington
2012-2019
Czech Technical University in Prague
2010
President University
2005
Well prepared It is well known that species radiate into new niches by adapting to novel environments. But why do some in this way, while other, related, not. Ishikawa et al. looked across sticklebacks determine some, originally marine, lineages were able colonize postglacial freshwater environments (see the Perspective Weber and Tong). They found a gene involved fatty acid desaturation was duplicated lineages. Transgenic manipulation of allowed marine synthesize acids thus survive on...
Severe droughts endanger ecosystem functioning worldwide. We investigated how drought affects carbon and water fluxes as well soil-plant-atmosphere interactions by tracing 13CO2 deep 2H2O label pulses volatile organic compounds (VOCs) in an enclosed experimental rainforest. Ecosystem dynamics were driven different plant functional group responses to drought. Drought-sensitive canopy trees dominated total but also exhibited the strongest response topsoil drying. Although all canopy-forming...
Monoterpenes (C10H16) are emitted in large quantities by vegetation to the atmosphere (>100 TgC year-1), where they readily react with hydroxyl radicals and ozone form new particles and, hence, clouds, affecting Earth's radiative budget thereby, climate change1-3. Although most monoterpenes exist two chiral mirror-image forms termed enantiomers, these (+) (-) rarely distinguished measurement or modelling studies4-6. Therefore, individual formation pathways of monoterpene enantiomers plants...
Deep rooting is considered a central drought-mitigation trait with vast impact on ecosystem water cycling. Despite its importance, little known about the overall quantitative use via deep roots and dynamic shifts of uptake depths changing ambient conditions. Knowledge especially sparse for tropical trees. Therefore, we conducted drought, soil labeling re-wetting experiment at Biosphere 2 Tropical Rainforest. We used in situ methods to determine stable isotope values tree high temporal...
Abstract Drought can affect the capacity of soils to emit and consume biogenic volatile organic compounds (VOCs). Here we show impact prolonged drought followed by rewetting recovery on soil VOC fluxes in an experimental rainforest. Under wet conditions rainforest acts as a net sink, particular for isoprenoids, carbonyls alcohols. The sink progressively decreases during drought, at moistures below ~19%, becomes source several VOCs. Position specific 13 C-pyruvate labeling experiments reveal...
Non-structural carbohydrates (NSCs) are building blocks for biomass and fuel metabolic processes. However, it remains unclear how tropical forests mobilize, export, transport NSCs to cope with extreme droughts. We combined drought manipulation ecosystem 13CO2 pulse-labeling in an enclosed rainforest at Biosphere 2, assessed changes NSCs, traced newly assimilated plant species diverse hydraulic traits canopy positions. show that caused a depletion of leaf starch reserves slowed export below...
Abstract Hydrogen isotope ratios of sedimentary leaf waxes (δ 2 H Wax values) are increasingly used to reconstruct past hydroclimate. Here, we add δ values from 19 lakes and four swamps on 15 tropical Pacific islands an updated global compilation published data surface sediments soils. Globally, there is a strong positive linear correlation between mean annual precipitation P the n ‐C 29 ‐alkane ( R = 0.74, 665) 28 ‐acid 242). Tropical fall within predicted range based calibration, largest...
The isotopic composition of xylem water (δX ) is considerable interest for plant source studies. In-situ monitored transpired (δT could provide a nondestructive proxy δX -values. Using flow-through leaf chambers, we 2-hourly δT -dynamics in two tropical species, one canopy-forming tree and understory herbaceous species. In an enclosed rainforest (Biosphere 2), observed response to experimental severe drought, followed by 2 H deep-water pulse applied belowground before starting regular rain....
Abstract Drought impacts on microbial activity can alter soil carbon fate and lead to the loss of stored atmosphere as CO 2 volatile organic compounds (VOCs). Here we examined drought allocation by microbes in Biosphere artificial tropical rainforest tracking 13 C from position-specific C-pyruvate into VOCs parallel with multi-omics. During drought, efflux C-enriched acetate, acetone 4 H 6 O (diacetyl) increased. These changes represent increased production buildup intermediate metabolites...
Reconstructions of past changes in algal community composition provide important context for future alterations biogeochemical cycling. However, many existing phytoplankton proxies are indicative individual groups and not fully representative the whole community. Here, we evaluated hydrogen isotope ratios lipids (δ2HLipid) as a potential proxy composition. We sampled water column Rotsee, small eutrophic lake Switzerland, every second week from January 2019 to February 2020 analyzed...
The stable isotopic composition of plant waxes (δ13C and δ2H values) in lake sediments is a powerful tool for reconstructing past climates environments, offering critical insights into hydroclimate variability vegetation dynamics. Different types, such as grasses woody vegetation, can exhibit distinct water sources fractionations, directly influencing plant-wax signatures sedimentary records. This influence particularly pronounced small basins, where local dominate over...
Throughout recent decades, cultural eutrophication has threatened freshwater ecosystem functioning. However, anthropogenic activity also heavily impacted aquatic environments earlier in human history. During the 2nd century BCE Aventicum (capital of Roman province Helvetica), located at southern border Murtensee, was inhabited by ~20,000 people. This led to significant disturbances lake and its environment, which persisted for centuries, including increased soil erosion, eutrophication,...
As direct mediators between plants and soil, roots play an important role in metabolic responses to environmental stresses such as drought, yet these are vastly uncharacterized on a plant-specific level, especially for co-occurring species. Here, we aim examine the effects of drought root profiles carbon allocation pathways three tropical rainforest species by combining cutting-edge metabolomic imaging technologies situ position-specific 13C-pyruvate root-labeling experiment. Further, washed...
Abstract Hydrogen isotope ratios ( 2 H / 1 , δ ) of leaf waxes covary with those in precipitation and are therefore a useful paleohydrologic proxy. Mangroves an exception to this relationship because their values also influenced by salinity. The mechanisms underlying response were investigated measuring lipid xylem water 18 O from three mangrove species over 9.5 months subtropical A ustralian estuary. Net fractionation between surface lipids decreased 0.5–1.0‰ ppt −1 for n ‐alkanes 0.4–0.8‰...