Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects.We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives. Geosphere-Biosphere Program (IGBP) and DIVERSITAS, the TRY database (TRY-not an acronym, rather a statement of sentiment; https ://www.try-db.org; Kattge et al., 2011) was proposed with the explicit assignment to improve the availability and accessibility of plant trait data for ecology and earth system sciences. The Max Planck Institute for Biogeochemistry (MPI-BGC) offered to host the database and the different groups joined forces for this community-driven program. Two factors were key to the success of TRY: the support and trust of leaders in the field of functional plant ecology submitting large databases and the long-term funding by the Max Planck Society, the MPI-BGC and the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, which has enabled the continuous development of the TRY database.

No abstract

14A fundamental and long-standing question of southern African palaeoclimatology is the way 15 tropical and temperate climate system dynamics have influenced rainfall regimes across the 16 subcontinent since the Last Glacial Maximum. In this paper, we analyse a selection of recently 17 published palaeoclimate reconstructions along a southwest-northeast transect across South Africa. 18These records span the last 22,000 years, and encompass the transition between the region's winter 19 and summer rainfall zones. In synthesis, these records confirm broad elements of the dominant 20 paradigm, which proposes an inverse coeval relationship between temperate and tropical systems, 21with increased precipitation in the winter (summer) rainfall zone during glacial (interglac ia l) 22 periods. Revealed, however, is a substantially more complex dynamic, with millennial-sca le 23 climate change events being strongly -even predominantly -influenced by the interaction and 24 combination of temperate and tropical systems. This synoptic forcing can create same sign 25 anomalies across the South African rainfall zones, contrary to expectations based on the classic 26 model of phase opposition. These findings suggest a new paradigm for the interpretation of 27 southern African palaeoenvironmental records that moves beyond simple binary or additive 28 influences of these systems. 29 30

Various studies report substantial increases in intrinsic water-use efficiency (W i), estimated using carbon isotopes in tree rings, suggesting trees are gaining increasingly more carbon per unit water lost due to increases in atmospheric CO2. Usually, reconstructions do not, however, correct for the effect of intrinsic developmental changes in W i as trees grow larger. Here we show, by comparing W i across varying tree sizes at one CO2 level, that ignoring such developmental effects can severely affect inferences of trees’ W i. W i doubled or even tripled over a trees’ lifespan in three broadleaf species due to changes in tree height and light availability alone, and there are also weak trends for Pine trees. Developmental trends in broadleaf species are as large as the trends previously assigned to CO2 and climate. Credible future tree ring isotope studies require explicit accounting for species-specific developmental effects before CO2 and climate effects are inferred.

No abstract

No abstract

No abstract

No abstract