Anàlisi espacio-temporal de la línia de costa i del foredune del sistema dunar de Sa Canova d’Artà (Mallorca)

[cat] Els sistemes platja-duna, són una de les morfologies sedimentàries més abundants a les Illes Balears. Aquests es troben composats per diferents subsistemes, els quals presenten diferents nivells de dinamisme. Des d’aquest punt de vista, la foredune és el sector més dinàmic de la part emergida del sistema i en la qual la vegetació té un paper clau per al desenvolupament de la resta del sistema. Tots i cada un dels sistemes existents a la comunitat autònoma i a la resta del món disposa d’una condicions/característiques que el fan peculiar i diferent a la resta; a part de les pròpies condicions físiques intrínseques al propi medi, a dia d’avui els sistemes han de fer front a tota una sèrie de pressions d’origen antròpic, destacant especialment l’activitat turística en el cas Balear. El cas d’estudi, és Sa Canova, situada al terme municipal d’Artà (NE de l’illa de Mallorca); aquest sistema tampoc n’és una excepció, al llarg del període d’estudi (1956-2012), ha sofert variacions, tant d’origen natural, com antròpic, les quals han tingut com a conseqüència el sistema dunar actualment existent.[eng] The beach-dune systems, are one of the most abundant sedimentary morphologies in the Balearic Islands. These are composed of different subsystems, which present different levels of dynamism. From this point of view, Foredune is the most dynamic sector of the emerging part of the system and in which vegetation plays a key role for the development of the rest of the system. Each and every one of the existing systems in the autonomous community and the rest of the world has conditions / characteristics that make it peculiar and different from the rest; Apart from the intrinsic physical conditions inherent in their own environment, today, systems have to deal with a whole series of pressures of anthropogenic origin, with special emphasis on tourism in the Balearic Islands. The case study is Sa Canova, located in the municipality of Artà (NE of the island of Mallorca); This system is not an exception either, during the period of study (1956-2012), it has undergone variations, both of natural origin and anthropic, which have resulted in the current dune system

Unbiased taxonomic annotation of metagenomic samples

The classification of reads from a metagenomic sample using a reference taxonomy is usually based on first mapping the reads to the reference sequences and then classifying each read at a node under the lowest common ancestor of the candidate sequences in the reference taxonomy with the least classification error. However, this taxonomic annotation can be biased by an imbalanced taxonomy and also by the presence of multiple nodes in the taxonomy with the least classification error for a given read. In this article, we show that the Rand index is a better indicator of classification error than the often used area under thereceiver operating characteristic (ROC) curve andF-measure for both balanced and imbalanced reference taxonomies, and we also address the second source of bias by reducing the taxonomic annotation problem for a whole metagenomic sample to a set cover problem, for which a logarithmic approximation can be obtained in linear time and an exact solution can be obtained by integer linear programming. Experimental results with a proof-of-concept implementation of the set cover approach to taxonomic annotation in a next release of the TANGO software show that the set cover approach further reduces ambiguity in the taxonomic annotation obtained with TANGO without distorting the relative abundance profile of the metagenomic sample.Peer ReviewedPostprint (published version

Nuclear and chloroplast DNA variation in Cephalaria squamiflora (Dipsacaceae), a disjunct Mediterranean species

Cephalaria squamiflora is a chamaephyte restricted to rupicolous habitats in islands of the Western (Balearic Islands, Sardinia) and Eastern Mediterranean (Crete and few Aegean islands). Four narrowly distributed races (subspp. squamiflora, mediterranea, ebusitana, balearica) have been described to encompass the morphological variation within the species. We have used nuclear ribosomal ITS and cpDNA sequences to assess how the patterns of molecular differentiation are related to taxonomic and geographic boundaries. Extensive intragenomic ITS variation was detected in samples from all territories, the average sequence divergence among cloned ribotypes was 1.339%. The parsimony network of cloned ITS sequences suggests a split between Eastern and Western Mediterranean accessions. Chloroplast DNA sequences showed five distinct haplotypes, only one of which was shared between islands (Majorca and Sardinia). Both nuclear and cpDNA markers supported the monophyly of the C. squamiflora complex and identified a highly structured pattern of molecular variation composed by sister monophyletic lineages that mirror major biogeographic units (Western and Eastern Mediterranean). The molecular evidence supports the hypotheses that vicariance events linked to the geological history of the region or dispersal across the Mediterranean may explain the distribution of the complex