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.
Our aims were to quantify and map the plant sub regions of the the Caatinga, that covers 844,453 km2 and is the largest block of seasonally dry forest in South America. We performed spatial analyses of the largest dataset of woody plant distributions in this region assembled to date (of 2,666 shrub and tree species; 260 localities), compared these distributions with the current phytogeographic regionalizations, and investigated the potential environmental drivers of the floristic patterns in these sub regions. Phytogeographical regions were identified using quantitative analyses of species turnover calculated as Simpson dissimilarity index. We applied an interpolation method to map NMDS axes of compositional variation over the entire extent of the Caatinga, and then classified the compositional dissimilarity according to the number of biogeographical sub regions identified a priori using k-means analysis. We used multinomial logistic regression models to investigate the influence of contemporary climatic productivity, topographic complexity, soil characteristics, climate stability since the last glacial maximum, and the human footprint in explaining the identified sub regions. We identified nine spatially cohesive biogeographical sub regions. Current productivity, as indicated by an aridity index, was the only explanatory variable retained in the best model, explaining nearly half of the floristic variability between sub regions. The highest rates of endemism within the Caatinga were in the Core and Periphery Chapada Diamantina sub regions. Our findings suggest that the topographic complexity, soil variation, and human footprint in the Caatinga act on woody plant distributions at local scales and not as determinants of broad floristic patterns. The lack of effect of climatic stability since the last glacial maximum probably results from the fact that a single measure of climatic stability does not adequately capture the highly dynamic climatic shifts the region suffered during the Pleistocene. There was limited overlap between our results and previous Caatinga classifications.
If logging and forest multiple-use are to be compatible with biodiversity conservation, then forest structure, composition and diversity must be expected to recover from the disturbance and eventually return to their former levels. Here we evaluate the long-term effects of selective logging and forest multiple-use on Southern Brazilian subtropical Araucaria mixed conifer-hardwood forest resilience at the landscape-scale. Longterm effects of different management regimes were compared between control undisturbed forests and forest stands subjected to early (55 years before this study) and recent (13 years) selective logging followed by undisturbed postharvest periods, and forest fragments subjected to selective logging followed by unregulated multiple-use by private landowners. Forest structure (tree density, basal area and height, and regeneration density) in early-logged areas was indistinguishable from control areas. Fragmentation and chronic disturbance, however, degraded forest fragments and kept them at early successional stages, with higher tree density, reduced basal area and scarce or absent regeneration. Mixed forests showed compositional resilience in the angiosperm component but not in the conifer component. Chronic disturbance kept forest fragments floristically away from mature and undisturbed secondary forests. Species richness in control and recently-logged plots did not differ significantly and was higher than richness in early-logged plots. Species richness was much reduced in degraded forest fragments. Density of the conifer Araucaria Electronic supplementary material The online version of this article (angustifolia, characteristic of the mature forest, was reduced in the fragments and in logged stands. We discuss how native forest management practices can be implemented to contribute positively to the conservation of the Araucaria mixed forest biodiversity.
In this paper I examined the usefulness of tree population size distributions in evaluating the conservation status of populations of an endangered tree species. I set expectations derived from two complimentary views of the ecology of rainforest trees and examined whether they were met by size distributions of populations of the South American dominant conifer Araucaria angustifolia and its relationship with forest structural characteristics. Specifically, I evaluated the expectations that (i) A. angustifolia trees have larger diameter than average angiosperm trees and form a higher monospecific canopy layer above the shorter angiosperm canopies; (ii) A. angustifolia populations are characterized by size distributions with many large individuals and a long tail of relatively rare, small individuals (have symmetry coefficient <0); (iii) the symmetry of the size distribution of A. angustifolia populations is negatively related to the abundance of large (d.b.h. Ն 10.0 cm) individuals in the population; and (iv) the abundance of A. angustifolia trees is negatively related to the abundance of angiosperm trees, as the successional accumulation of angiosperm stems would not be accompanied by the recruitment of new A. angustifolia. These expectations were evaluated using data on 25 populations of A. angustifolia sampled in the Rio Grande do Sul State in southern Brazil. The first, third and fourth expectations were met, while the second one was only partially met. This was because populations showed a bimodal distribution regarding symmetry in size distribution, with most populations showing normal or negative symmetry, and those logged, adult-depleted populations showing positive skewness.
We investigated the patterns of growth and reproduction of the understory clonal palm Geonoma brevispatha based on the identification of post-germinative ontogenetic stages, over a 3-year period. Genets were monitored in 100 5 × 5 m plots and 100 2 × 2 m subplots, in a 1-ha area of swamp forest in São Paulo state, southeastern Brazil. Ramets pass through four ontogenetic stages (bifid-leafed juveniles, pinnatifid-leafed stemless immatures, stemmed nonreproductive virgins, and reproducers). Leaf size, leaf number, and leaf production rate increased during ontogeny, but diameter growth rate was higher among immatures. Stem length, number of nodes, and leaf rachis length were positively correlated across ontogenetic stages, but crown height was smaller than stem length in adult palms because of frequent leaning. Leaf number and sexual fecundity increased with ramet size, but declined in larger, senescent ramets. Clonal fecundity preceded sexual fecundity, and sexual and clonal fecundity increased continuously with genet size. No relationship was found between sexual and clonal fecundity. Growth and survival strategies of G. brevispatha were consistent with the patterns found in other tropical clonal palm species. Sexual fecundity and cloning seem to be two integrated processes favored by environmental conditions that also support the growth of existing ramets.Key words: stage-structured populations, ontogenetic stages, swamp forest, Brazil, Atlantic forest, senescence.
Our aims were to quantify and map the plant ecoregions of the Atlantic Forest, a biodiversity hotspot that covers ca 150 million ha in eastern South America. We used a data set on the distribution of 4378 shrub and tree species across 711 localities. Plant ecoregions were identified using analyses of species turnover for both species occurrences and relative abundances. We interpolated NMDS axes of compositional variation over the entire the Atlantic Forest extent, and then classified the compositional dissimilarity according to the number of biogeographical ecoregions previously identified through K-means analyses. We assessed the ability of environmental, historical vegetation stability and the current human footprint to explain the occurrence of the identified ecoregions through multinomial logistic regression models. We identified 21 spatially cohesive occurrence and 14 abundance ecoregions. Aridity, soil and historical biome stability were retained in the best model explaining both occurrence and abundance ecoregions. Broad compositional zones were identified through UPGMA cluster analysis of ecoregions, and formed north and south compositional blocks. Our work confirms the existence of a broad north-south divide within the Atlantic Forest, previously suggested based on climatic and amphibious data. Differences between the occurrence and abundance maps suggest the location of transition zones to neighbouring domains and endemism centres. Due to the aggregate nature of our analyses, site-level disturbance degree was not considered, implying that human impacts could be broader then we could detect. There was limited overlap between our results and previous Atlantic Forest regionalization efforts, indicating that multi-taxa, physiognomic and environmental regionalization schemes based on expert opinion or vegetation maps are poor proxies for compositional ecoregions.
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