Caracterización florística y fitoecológica de las turberas de las Sierras de Xistral y Ancares (NW Península Ibérica)

[Resumen] Las turberas son ecosistemas de gran importancia ambiental que presentan una distribución muy restringida en la Península Ibérica. En Galicia, se consideran representados dos grandes tipos de turberas, minerotrófi cas y ombrotrófi cas, aunque su caracterización sigue siendo fuente de controversias al igual que su vegetación. En este estudio se analizaron las turberas presentes en las Sierras do Xistral y Ancares (NW Península Ibérica) para caracterizar su fl ora y vegetación y analizar los factores ambientales que determinan la presencia de las especies que allí crecen. Se evaluaron 29 variables ambientales, y de ellas las que más condicionaron la distribución de la fl ora están relacionadas fundamentalmente con su origen geográfi co y localización, siendo a nivel local la temperatura mínima del sustrato y el nivel freático mínimo las más importantes. Los análisis realizados permitieron seleccionar un método numérico que permite identifi car las comunidades vegetales de forma objetiva. Se presenta una tabla de equivalencias entre las diversas clasifi caciones disponibles para facilitar la gestión de estos medios en Galicia. Finalmente, se ha realizado un análisis de la lluvia polínica actual para comprobar su representatividad con respecto a la fl ora presente en la actualidad en estos ambientes.[Abstract] Peatlands are environmentally important systems that show a very restricted distribution in the Iberian Peninsula. In Galicia, two major types of peatlands can be found, ombrotrophic and minerotrophic. The differentiation between these types, as well as the characterization of their vegetation, remains controversial. In this study, peatlands present in the Sierras do Xistral and Ancares (NW Iberian Peninsula) were analyzed in order to characterize their fl ora and vegetation. In addition to this, we analyzed the putative impact of 29 environmental variables in the distribution of plant species. We observed that the environmental factors most affecting the fl ora in these environments were mainly related to the geographical origin and location of the different species. More particularly, the minimum temperature of the substrate and the largest minimum water table were the most important variables. Our results have allowed us to select a numerical method able to identify peatland plant communities in an objective manner. A table of equivalence among the different vegetation classifi cations including plant communities is presented in order to facilitate the management of these ecosystems in Galicia. Finally, we have analyzed current pollen rain in the selected peatlands in order to check its accuracy representing the fl ora currently growing in these areas.[Resumo] As turbeiras (brañas ou tremoais) son ecosistemas de gran importancia ambiental que presentan unha distribución moi restrinxida na Península Ibérica. En Galicia, considéranse representados dous grandes tipos de turbeiras, minerotrófi cas e ombrotrófi cas, se ben a súa caracterización segue a ser fonte de controversias ó igual que a súa vexetación. Neste estudo analizáronse as turbeiras presentes nas Serras do Xistral e Ancares (NW Península Ibérica) para caracterizar a súa fl ora e vexetación e analizar os factores ambientais que determinan a súa distribución. Avaliáronse 29 variables ambientais das cales, as que máis condicionan a distribución das especies relaciónanse fundamentalmente coa súa orixe xeográfi ca e localización, sendo a temperatura mínima do substrato e o nivel freático mínimo os máis importantes. As análisis realizadas permitiron seleccionar un método numérico que permite identifi car as comunidades vexetais de xeito obxectivo. Como resultado deste traballo preséntase asimesmo unha taboa de equivalencias entre estas clasifi cacións, co gallo de facilitar a xestión de estes medios en Galicia. Finalmente, realizouse unha análise da choiva polínica actual para comprobar a representatividade do rexistro polínico con respecto á fl ora presente na actualidade nestes ambientes

The crustal structure of the Cantabrian Mountains revealed by new magnetotelluric soundings

The upper crustal structure of the central Cantabrian Mountains consists of a block of Variscan basement uplifted over the Duero basin as a consequence of a southward displacement along a major thrust during the convergence between Europe and Iberia in the Eocene-Oligocene (Alpine orogeny). We present the results of the 3-D modeling of thirteen new magnetotelluric sites, five of them being completed by long period data, over a 100 km-long, N-S oriented profile across the central Cantabrian Mountains and the Duero basin. Dimensionality analyses indicated a dominant E-W direction but with influence of 3-D structures at long periods and locally in the Cantabrian Mountains. Accordingly, we performed a 3-D joint inversion of the full impedance tensor and the geomagnetic transfer function following a sequential inversion workflow. The inverse model presents similarities with existing lithospheric models. In the southern part of the area, the conductive sediments of the Duero basin over a high resistive and homogeneous Iberian lithosphere are well delineated. Towards the north, beneath the Cantabrian Mountains, the model reveals a heterogeneous and conductive lithosphere, in which various elongated and dipping conductors in the upper and middle crust are associated with major Alpine thrusts, one being the frontal thrust of the Cantabrian Mountains over the Duero basin. At deeper depths (between 20 and 35 km depth), the Iberian crust appears as subducting to the north beneath a conductive zone interpreted as the hydrated mantle wedge of the north-Iberian continental margin

NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data