Update: Decomposing beta diversity

Abstract

news and update Paulo Borges (University of Azores, Azorean Biodiversity Group), described the Azorean Biodi- versity Portal (http://www.azoresbioportal.angra. uac.pt/) and highlighted the importance of science communication for the general public, putting is- land biodiversity on the web. He also explained the importance of standardized studies and moni- toring of island ecosystems using Long Term Eco- logical Studies (LTER). Frederico Cardigos (representing the Azor- ean and Madeiran Governments) affirmed that along the whole processes of governance and na- ture conservation policies, it is assumed that pub- lic perception is of great importance and has a considerable impact on the way politicians react. In addition he presented the plan of the Azorean Government for the management of both terres- trial and marine environments. Antonio Machado referred that the task is immense and complex, and that as an island de- creases in size and its distance to the mainland increases (isolation), its ecological vulnerabil- ityalso increases, the data is scarcer, and there is insufficient local technical capacity and lack of political commitment. IAS on Islands were discussed by Juan Luis Rodriguez Luengo (Canary Islands) that presented the TOP100 Macaronesian initiative, Piero Geno- vesi (Italy) that presented the ISSG (Invasive Spe- cies Specialist Group), Lucilla Carnevali that pre- sented the database on IAS in European Islands and Sarah Brunel (EPPO), that talked on Biosecu- rity in Islands – Using Plant heath instrument to control IAS. Invasive species were considered the ISSN 1948-6596 most important problem to the conservation of the native island biota and ecosystems. By the end of the meeting the Priorities for action and Proposals to the Standing Committee of the Bern Convention were discussed under the coordination of Eladio Fernandez-Galiano. Sugges- tions included: EU legislation dedicated to IAS on islands; portfolio of biodiversity on islands; man- ual of best practices; establishing working groups (climate change; IAS; IUCN criteria revision adapted to islands and invertebrates; communica- tion improvement); for the parties – special atten- tion to natural systems on islands promoting ini- tiatives of biodiversity information gathering. A major challenge of this group of Experts on Island Biological Diversity is to influence the policy-makers, managers and general public on the importance of putting special resources for the conservation of island biota and ecosystems, maintaining also a sustainable life for island hu- man populations. The solid experience and knowledge in is- land ecosystems of most of the experts that par- ticipated in this meeting, together with the com- mitment of local politicians is a strong indicator that the goals of this meeting will be entirely achieved, and that we will create an international network of expertise in island studies. Paulo A. V. Borges Azorean Biodiversity Group, University of the Azores, Portugal http://cita.angra.uac.pt/biodiversidade/ update Decomposing beta diversity Baselga (2009) proposes a creative analysis to de- compose patterns of beta diversity into effects of nestedness and species turnover. This kind of ap- proach moves us closer to distinguishing different mechanisms that can contribute to observed measures of beta diversity. Two additional consid- erations will help to improve this analysis. First, more effort should be devoted to carefully exploring the statistical performance of this index with artificial data sets that have speci- fied amounts of randomness and structure. The analyses presented in Figures 2 and 3 are an excel- lent start, but we need an expanded analysis of different kinds of benchmark matrices to evaluate the potential for Type I errors (incorrectly reject- ing a true null hypothesis) and Type II errors (incorrectly accepting a false null hypothesis). These kinds of tests are challenging because they © 2009 the authors; journal compilation © 2009 The International Biogeography Society — frontiers of biogeography 1.2, 2009