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Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at‐sea threat...
Common, low-frequency, rare, and ultra-rare coding variants contribute to COVID-19 severityNARA Subscribed
The combined impact of common and rare exonic variants in COVID-19 host genetics is currently insufficiently understood. Here, common and rare variants from whole-exome sequencing data of about 4000 SARS-CoV-2-positive individuals were used to define an interpretable machine-learning model for predicting COVID-19 severity. First, variants were converted into separate sets of Boolean features, depending on the absence or the pr...
Given that forests represent the primary terrestrial sink for atmospheric CO 2 , projections of future carbon (C) storage hinge on forest responses to climate variation. Models of gross primary production ( GPP ) responses to water stress are commonly based on remotely sensed changes in canopy ‘greenness’ (e.g., normalized difference vegetation index; NDVI ). However, many forests have low spectral sensitivity to water stress...
Chronic water stress reduces tree growth and the carbon sink of deciduous hardwood forestsNARA Subscribed
Predicted decreases in water availability across the temperate forest biome have the potential to offset gains in carbon (C) uptake from phenology trends, rising atmospheric CO 2 , and nitrogen deposition. While it is well established that severe droughts reduce the C sink of forests by inducing tree mortality, the impacts of mild but chronic water stress on forest phenology and physiology are largely unknown. We quantified th...
Summary This study used an environmentally controlled plant growth facility, EcoCELLs, to measure canopy gas exchanges directly and to examine the effects of elevated [CO 2 ] on canopy radiation‐ and water‐use efficiencies. Sunflowers ( Helianthus annus var. Mammoth) were grown at ambient (399 μmol mol −1 ) and elevated [CO 2 ] (746 μmol mol −1 ) for 53 days in EcoCELLs. Whole canopy carbon‐ and water‐fluxes were measured cont...
Summary The effect of elevated CO 2 on photosynthesis, respiration, and growth efficiency of sunflower plants at the whole‐stand level was investigated using a whole‐system gas exchange facility (the EcoCELLs at the Desert Research Institute) and a 13 C natural tracer method. Total daily photosynthesis (GPP), net primary production (NPP), and respiration under the elevated CO 2 treatment were consistently higher than under the...
Carbon budgeting in plant–soil mesocosms under elevated CO 2 : locally missing carbon?NARA Subscribed
Summary Studies have suggested that more carbon is fixed due to a large increase in photosynthesis in plant–soil systems exposed to elevated CO 2 than could subsequently be found in plant biomass and soils –‐ the locally missing carbon phenomenon. To further understand this phenomenon, an experiment was carried out using EcoCELLs which are open‐flow, mass‐balance systems at the mesocosm scale. Naturally occurring 13 C tracers...
Nonlinearity of photosynthetic responses to growth in rising atmospheric CO 2 : an experimental and modelling studyNARA Subscribed
Nonlinear responses of photosynthesis to the CO 2 concentration at which plants were grown (C g ) have been often reported in the literature. This study was designed to develop mechanistic understanding of the nonlinear responses with both experimental and modelling approaches. Soybean (Glycine max) was grown in five levels of C g (280, 350, 525, 700, 1000 ppm) with either a high or low rate of nitrogen fertilization. When the...
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