Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

Designing analytical approaches for interactive competitive intelligence

Der Begriff der Resilienz erfährt aktuell eine starke Resonanz in der Wirtschaftsgeographie. Das Platzen der Dotcom-Blase und die Finanz- und Wirtschaftskrise Ende der 2000er Jahre werfen Fragen dazu auf, wie ökonomische Krisen entstehen und wie sie vermieden oder gemeistert werden können. Auch Herausforderungen des Klimawandels, der Ressourcenverknappung oder des demographischen Wandels wirken sich auf ökonomische Systeme aus. Staaten und Regionen sind von Krisen nicht nur in unterschiedlichem Maße betroffen, auch ihre Reaktionen darauf unterscheiden sich erheblich. Einige gehen gestärkt aus Krisen hervor, andere werden in ihrer Entwicklung zurückgeworfen, und wieder andere scheinen kaum betroffen zu sein. Ist dieser Umstand begründet in einer unterschiedlich starken Resilienz? Und wenn j a, welche Prozesse bedingen oder beeinflussen eine mehr oder weniger starke Resilienz von räumlichen Einheiten

Sheet hyaloclastite: density-current deposits of quench and bubble-burst fragments from thin, glassy sheet lava flows, Seamount Six, Eastern Pacific Ocean

New observations with the submersible ALVIN and deep-tow camera show that bedded sheet-hyaloclastites are common deposits between 2024 and 1723 m depth on the upper flank of Seamount Six, located on the Cocos plate at 12°45′N, 102°35′W. The individual sheets are highly localized and of small areal extent (<200 m2), though no vent sites were found. Several facies associations of hyaloclastite, with pillow talus, knobbly fist-sized lava fragments and thin sheet lava (<10 cm) underlying hyaloclastite, are identified. Recovered samples consist of angular, polyhedral sand-sized sideromelane shards and thin, bent, plate-like sideromelane fragments called Limu O'Pelee. Limu are solidified fragments of burst magma bubbles, which formed by vapourization of water entrapped by lava. Analysis of lava and hyaloclastite shards including limu shows three geochemically distinct populations, depleted MORB (N1), more evolved NMORB (N2) and hawaiite (H) of diverse composition. In individual hyaloclastite samples, shards of two or three different types may occur in various proportions, though in samples of hyaloclastite associated with sheet lava the predominant shards are of the same geochemical type as the sheet lava. Deposition of hyaloclastites occurred from lateral density currents formed by transformation from convective suspension settling. Grain size distribution, settling behaviour of different co-deposited shard types and sedimentary structures, together with pelagic ooze in the matrix and geochemically mixed shard populations, indicate some erosion, traction reworking and turbulence during transport. Critical observations are that contorted sheet lava protrudes through hyaloclastite and that sheet lava flow vugs commonly contain pelagic ooze. Facies associations plus consideration of limu formation allow the establishment of a new, multi-component model of hyaloclastite formation. It is inferred that the formation of limu-bearing sheet hyaloclastite involves entrapment of pelagic sediment beneath or within lava. This leads to limu bubble formation and suppressed tephra jetting. Together with convectively rising water heated by the lava flow, these processes loft shards slightly into the water column, from which they settle singly or in vertical sediment gravity flows that are redirected to flow along the seafloor

A semantic web faceted search system for facilitating building of biodiversity and ecosystems services

To address biodiversity issues in ecology and to assess the consequences of ecosystem changes, large quantities of long-term observational data from multiple datasets need to be integrated and characterized in a unified way. Linked open data initiatives in ecology aim at promoting and sharing such observational data at the web-scale. Here we present a web infrastructure, named Thesauform, that fully exploits the key principles of the semantic web and associated key data standards in order to guide the scientific community of experts to collectively construct, manage, visualize and query a SKOS thesaurus. The study of a thesaurus dedicated to plant functional traits demonstrates the potential of this approach. A point of great interest is to provide each expert with the opportunity to generate new knowledge and to draw novel plausible conclusions from linked data sources. Consequently, it is required to consider both the scientific topic and the objects of interest for a community of expertise. The goal is to enable users to deal with a small number of familiar and conceptual dimensions, or in other terms, facets. In this regard, a faceted search system, based on SKOS collections and enabling thesaurus browsing according to each end-users requirements is expected to greatly enhance data discovery in the context of biodiversity studies

A semantic web faceted search system for facilitating building of biodiversity and ecosystems services

To address biodiversity issues in ecology and to assess the consequences of ecosystem changes, large quantities of long-term observational data from multiple datasets need to be integrated and characterized in a unified way. Linked open data initiatives in ecology aim at promoting and sharing such observational data at the web-scale. Here we present a web infrastructure, named Thesauform, that fully exploits the key principles of the semantic web and associated key data standards in order to guide the scientific community of experts to collectively construct, manage, visualize and query a SKOS thesaurus. The study of a thesaurus dedicated to plant functional traits demonstrates the potential of this approach. A point of great interest is to provide each expert with the opportunity to generate new knowledge and to draw novel plausible conclusions from linked data sources. Consequently, it is required to consider both the scientific topic and the objects of interest for a community of expertise. The goal is to enable users to deal with a small number of familiar and conceptual dimensions, or in other terms, facets. In this regard, a faceted search system, based on SKOS collections and enabling thesaurus browsing according to each end-users requirements is expected to greatly enhance data discovery in the context of biodiversity studies

Harmonizing, annotating and sharing data in biodiversityecosystem functioning research

The integrative research field of biodiversityecosystem functioning (BEF) requires close collaboration between researchers from different disciplines working on different scales in time, space as well as taxon resolution. Data can describe anything from abiotic ecosystem components, to organisms, parts of organisms, genetic information or element stocks and flows. Researchers prefer the convenience of spreadsheets for data preparation, which can lead to isolated data sets that are diverse in structure and follow diverging naming conventions. BEFdata (https://github.com/befdata/befdata) is a new, open source web platform for the upload, validation and storage of data from a formatted Excel workbook. Metadata can be downloaded in Ecological Metadata Language (EML). BEFdata allows the harmonization of naming conventions by generating category lists from the primary data, which can be reviewed and managed via the Excel workbook or directly on the platform. BEFdata provides a secure environment during ongoing analysis; project members can only access primary data from other researchers after the acceptance of a data request. Due to its generic database schema, BEFdata platforms can be used for any research domain working with tabular data. It supports the compilation of coherent data sets at the level of the primary data, allowing researchers to explicitly model correlation structures across data sets for synthesis. The EML export enables efficient publishing of data in global repositories