144 research outputs found
SIVIM Alpine - Database of high-mountain grasslands in the Iberian Peninsula
SIVIM Alpine (GIVD ID: EU-00-034) is a thematic database focused on vegetation plots from alpine grasslands of the Iberian Peninsula. The main aim of the database is to centralize historical and new vegetation plots of grassland-like communities above the treeline from Spanish mountains, the Pyrenees (including France and Andorra) and Serra da Estrela (Portugal). The database was registered in GIVD in December 2020, and it is currently available in EVA under semi-restricted regime. SIVIM Alpine includes both digitized relevés from the literature and unpublished data. Most of digitized relevés overlap with SIVIM (GIVD ID EU-00-004) but the header data and the geographical coordinates of SIVIM Alpine have been improved when possible. The database is routinely updated with new surveys conducted with GPS and detailed ecological data. Nowadays, SIVIM Alpine contains 6,420 vegetation plots corresponding to all phytosociological alliances described in the Iberian Peninsula for high-mountain grassland vegetation, 85% of them also classified at the association level. Plot size is available for 80% of the relevés. Plant taxonomy keeps the names provided by the original authors of the relevés, with an additional correspondence to Euro+Med and The Plant List, when possible. The database is continuously updated by revisiting the original sources. Different versions of the database have been used to vegetation analysis at national at continental scales
Destinos de un biólogo cantábrico
Perfil biográfico del autor tras su paso por la Facultad de Biología de la Universidad de León, su estancia en Italia culminando con la lectura de su tesis doctoral en al año 200
Beta-diversity of Central European forests decreases along an elevational gradient due to the variation in local community assembly processes
Beta-diversity has been repeatedly shown to decline with increasing
elevation, but the causes of this pattern remain unclear, partly because they
are confounded by coincident variation in alpha- and gamma-diversity. We used
8,795 forest vegetation-plot records from the Czech National Phytosociological
Database to compare the observed patterns of beta diversity to null-model
expectations (beta-deviation) controlling for the effects of alpha- and
gamma-diversity. We tested whether \b{eta}-diversity patterns along a 1,200 m
elevation gradient exclusively depend on the effect of varying species pool
size, or also on the variation of the magnitude of community assembly
mechanisms determining the distribution of species across communities (e.g.,
environmental filtering, dispersal limitation). The null model we used is a
novel extension of an existing null-model designed for presence/absence data
and was specifically designed to disrupt the effect of community assembly
mechanisms, while retaining some key features of observed communities such as
average species richness and species abundance distribution. Analyses were
replicated in ten subregions with comparable elevation ranges. Beta-diversity
declined along the elevation gradient due to a decrease in gamma-diversity,
which was steeper than the decrease in alpha-diversity. This pattern persisted
after controlling for alpha- and gamma-diversity variation, and the results
were robust when different resampling schemes and diversity metrics were used.
We conclude that in temperate forests the pattern of decreasing beta-diversity
with elevation does not exclusively depend on variation in species pool size,
as has been hypothesized, but also on variation in community assembly
mechanisms. The results were consistent across resampling schemes and diversity
measures, thus supporting the use of vegetation plot databases for
understanding...Comment: Accepted version 25 pages, 5 figures, 1 tabl
- …