Publications by authors named "O Kolle"
Automating dynamic fine root data collection in the field is a longstanding challenge with multiple applications for co-interpretation and synthesis for ecosystem understanding. High frequency root data are only achievable with paired automated sampling and processing. However, automatic minirhizotron (root camera) instruments are still rare and data are often not collected in natural soils or analysed at high temporal resolution.
View Article and Find Full Text PDFDrought and heatwave impacts on semi-arid ecosystems' carbon fluxes along a precipitation gradient.
Philos Trans R Soc Lond B Biol Sci
October 2020
Article Synopsis
- The terrestrial carbon cycle's inter-annual variability (IAV) is closely connected to semi-arid ecosystems, making it critical to identify meteorological factors affecting these ecosystems and their responses to extreme events like droughts and heatwaves.
- A four-year analysis of carbon fluxes at two FLUXNET sites in Spain revealed that the wetter ecosystem was less affected by soil water changes, while the drier site became a CO2 sink during wetter years.
- The study indicates that the timing of droughts significantly impacts yearly carbon fluxes, emphasizing that drought events in spring or autumn are more crucial than summertime heatwaves.
Article Synopsis
- - The FLUXNET2015 dataset encompasses ecosystem-scale data on carbon dioxide, water, and energy exchange, collected from 212 global sites contributing over 1500 site-years of data until 2014.
- - The dataset was systematically quality controlled and processed, facilitating consistency for various applications in ecophysiology, remote sensing, and ecosystem modeling.
- - For the first time, derived data products such as time series, ecosystem respiration, and photosynthesis estimates are included, and 206 sites are made accessible under a Creative Commons license, with the processing methods available as open-source codes.
Gross primary productivity (GPP), the gross uptake of carbon dioxide (CO) by plant photosynthesis, is the primary driver of the land carbon sink, which presently removes around one quarter of the anthropogenic CO emissions each year. GPP, however, cannot be measured directly and the resulting uncertainty undermines our ability to project the magnitude of the future land carbon sink. Carbonyl sulfide (COS) has been proposed as an independent proxy for GPP as it diffuses into leaves in a fashion very similar to CO, but in contrast to the latter is generally not emitted.
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