Plant traits – the morphological, anatomical, physiological, biochemical and phenological characteristics of plants and their organs – determine how primary producers respond to environmental... Show morePlant traits – the morphological, anatomical, physiological, biochemical and phenological characteristics of plants and their organs – determine how primary producers respond to environmental factors, affect other trophic levels, influence ecosystem processes and services and provide a link from species richness to ecosystem functional diversity. Trait data thus represent the raw material for a wide range of research from evolutionary biology, community and functional ecology to biogeography. Here we present the global database initiative named TRY, which has united a wide range of the plant trait research community worldwide and gained an unprecedented buy-in of trait data: so far 93 trait databases have been contributed. The data repository currently contains almost three million trait entries for 69 000 out of the world’s 300 000 plant species, with a focus on 52 groups of traits characterizing the vegetative and regeneration stages of the plant life cycle, including growth, dispersal, establishment and persistence. A first data analysis shows that most plant traits are approximately log-normally distributed, with widely differing ranges of variation across traits. Most trait variation is between species (interspecific), but significant intraspecific variation is also documented, up to 40% of the overall variation. Plant functional types (PFTs), as commonly used in vegetation models, capture a substantial fraction of the observed variation – but for several traits most variation occurs within PFTs, up to 75% of the overall variation. In the context of vegetation models these traits would better be represented by state variables rather than fixed parameter values. The improved availability of plant trait data in the unified global database is expected to support a paradigm shift from species to trait-based ecology, offer new opportunities for synthetic plant trait research and enable a more realistic and empirically grounded representation of terrestrial vegetation in Earth system models. Show less
Background: Severe (PiZZ) and moderate (PiSZ) alpha-1-antitrypsin (AAT) deficiency predispose to lung emphysema, especially in smokers. We hypothesized that multi-slice computed tomography (CT)... Show moreBackground: Severe (PiZZ) and moderate (PiSZ) alpha-1-antitrypsin (AAT) deficiency predispose to lung emphysema, especially in smokers. We hypothesized that multi-slice computed tomography (CT) might be superior to pulmonary function tests (PFT) to detect lung emphysema in AAT-deficient individuals at the age of 32 years. Methods: A subgroup of PiZZ and PiSZ individuals identified during the Swedish newborn screening programme in 1972-74 underwent multi-slice CT and PFT at the age of 32 years. From the CT scans the percentile density at 15% (PD15) and the relative area below -910 Hounsfield Units (RA(-910) HU) were calculated. The results of PFT and CT were compared between the AAT-deficient individuals and an age-matched control group. Results: Twenty-five PiZZ, 11 PiSZ and 17 PiMM individuals participated in the study. All Pi subgroups had normal lung function. The mean PD15 was 81 (SD 22) g/L in the PiZZ individuals, 96 (SD 35) g/L in the PiSZ individuals and 79 (SD 17) g/L in the PiMM individuals (ns), and the RA-910 were 30 (SD 18)%, 24 (SD 20)%, and 32 (SD 18)%, respectively (ns). For the never-smoker subgroups, in the PiZZ (n = 23), PiSZ (n = 8) and PiMM (n = 12), the mean PD15 were 95 (SD 35) g/L, 81 (SD 22) g/L, and 75 (SD 12) g/L, respectively (ns). PD15 was significantly correlated to CT derived lung size (r = -0.72; p < 0.001). Conclusions: CT densitometry revealed no signs of emphysema and no differences between the AAT-deficient individuals identified by neonatal screening and age-matched control subjects. (C) 2010 Elsevier Ltd. All rights reserved, Show less
