0000000000148705

AUTHOR

Ulrich Weber

Environment-sensitivity functions for gross primary productivity in light use efficiency models

International audience; The sensitivity of photosynthesis to environmental changes is essential for understanding carbon cycle responses to global climate change and for the development of modeling approaches that explains its spatial and temporal variability. We collected a large variety of published sensitivity functions of gross primary productivity (GPP) to different forcing variables to assess the response of GPP to environmental factors. These include the responses of GPP to temperature; vapor pressure deficit, some of which include the response to atmospheric CO2 concentrations; soil water availability (W); light intensity; and cloudiness. These functions were combined in a full fact…

research product

The FLUXCOM ensemble of global land-atmosphere energy fluxes

Although a key driver of Earth’s climate system, global land-atmosphere energy fluxes are poorly constrained. Here we use machine learning to merge energy flux measurements from FLUXNET eddy covariance towers with remote sensing and meteorological data to estimate global gridded net radiation, latent and sensible heat and their uncertainties. The resulting FLUXCOM database comprises 147 products in two setups: (1) 0.0833° resolution using MODIS remote sensing data (RS) and (2) 0.5° resolution using remote sensing and meteorological data (RS + METEO). Within each setup we use a full factorial design across machine learning methods, forcing datasets and energy balance closure corrections. For…

research product

Compensatory water effects link yearly global land CO2 sink changes to temperature

Large interannual variations in the measured growth rate of atmospheric carbon dioxide (CO2) originate primarily from fluctuations in carbon uptake by land ecosystems1–3. It remains uncertain, however, to what extent temperature and water availability control the carbon balance of land ecosystems across spatial and temporal scales3–14. Here we use empirical models based on eddy covariance data15 and process-based models16,17 to investigate the effect of changes in temperature and water availability on gross primary productivity (GPP), terrestrial ecosystem respiration (TER) and net ecosystem exchange (NEE) at local and global scales. We find that water availability is the dominant driver of…

research product

No diagnostic utility of antibody patterns against Klebsiella pneumoniae capsular serotypes in patients with axial spondyloarthritis vs. patients with non-specific low back pain:a cross-sectional study

OBJECTIVES: To investigate whether antibody response patterns against Klebsiella pneumoniae capsular serotypes can discriminate patients with axial spondyloarthritis (axSpA) from patients with non-specific low back pain (LBP).METHOD: Immunoglobulin (Ig)G and IgA antibodies against K. pneumoniae capsular serotypes K2, K26, K36, and K50 were measured, and antibody seropositivity compared between groups and analysed for patient correlation in five different groups: (a) 96 patients fulfilling the Assessment of SpondyloArthritis International Society (ASAS) classification criteria for axSpA; (b) 38 patients with either a positive magnetic resonance imaging (MRI) scan as defined by ASAS or a posi…

research product

FRI0194 Is There an Association Between Spondyloarthritis and Antibodies Towards Borrelia, Ehrlichia and Chlamydia Species?

Background Several studies suggested that certain microorganisms might contribute to initiation and perpetuation of spondyloarthritis (SpA). Objectives To investigate IgG and IgM antibodies towards Borrelia burgdorferi (Bb), Borrelia garinii (Bg), Borrelia afzelii (Ba), Ehrlichia spp. (Ehr), Chlamydia trachomatis (Ct), and Chlamydia pneumoniae (Cp) in SpA patients, low back pain patients, and healthy subjects and to elucidate whether previous infections could play a role in the onset of SpA. Methods Data collection was based on persons aged 18-40 years referred with low back pain for ≥3 months. They were examined with MRI of the spine and sacroiliac joints, CRP, HLA-B27, and clinical SpA fe…

research product