Search

Several studies have reported glacial refugia and migration pathways for different pine species in the Iberian Peninsula, all of them based on a single-species approach. In this paper, chloroplast microsatellites (cpSSRs) are used to compare population genetic structure and diversity estimates for interspecific pairs of populations located along a cline from southwestern (latitude 36°32′ N, longitude 5°17′ W) to northeastern Spain (latitude 42°14′ N, longitude 2°47′ E) in two widely distributed Mediterranean pines,Pinus halepensisMill. andPinus pinasterAit. Some cpSSRs were shared between species, facilitating comparison of levels of gene diversity at the species level and inferences about within and among species differentiation.P. pinastershowed a much higher number of variants (29) and haplotypes (69) thanP. halepensis(20 and 21, respectively). Moreover, genetic diversity estimates for interspecific pairs of populations along the cline were negatively correlated. Three main causes may explain the differences between species in the present-day distribution of genetic diversity: (1) the distribution of genetic variability before the Quaternary glaciations, with an earlier presence ofP. pinasterin the Iberian Peninsula and a late spread ofP. halepensisfrom eastern and central Europe, (2) the location of the Holocene glacial refugia and the migration pathways from these refugia to the present-day range (from northeast to southwest inP. halepensisand from southwest to northeast and northwest inP. pinaster) and (3) the interactions between species during the postglacial spread. [ABSTRACT FROM AUTHOR]

SummaryRepresentativeness is a desirable property of conservation networks. In this paper an attempt is made to assess the efficiency of current conservation networks in Portugal in representing vertebrates (reptiles and amphibians) and plants (gymnosperms, pteridophytes and bryophytes). It was found that whilst the protected areas do not sample all species in the database they provide a better result than choosing areas at random. For the goal of maximizing representation of taxa per unit area hotspots and complementarity performed better. A pattern of over-representation of vertebrates in relation to lower plants was discovered among selected conservation areas in Portugal suggesting that charismatic organisms with large home ranges may not always be the most appropriate surrogates for biodiversity when representativeness is sought. When trying to fill the gaps in current protected areas with additional areas only complementarity performed better than choosing areas at random. Both rarity and richness hotspots gave worse results. Opportunistic administrative criteria such as supplementing the PAS with other conservation areas (CORINE Biotopes) without taking into account their contribution to a representation goal was nearly half as good as choosing areas at random. The results recall for the need of explicit goals and accountable methods in area selection for conservation and reinforce the role of complementarity for finding additional areas to protected areas when limited resources are available for ‘in situ’ conservation. [ABSTRACT FROM AUTHOR]