Julio Peñas

Assessing extinction-risk of endangered plants using species distribution models: a case study of habitat depletion caused by the spread of greenhouses

The species distribution models (SDMs) are useful tools for investigating rare and endangered species as well as the environmental variables affecting them. In this paper, we propose the application of SDMs to assess the extinction-risk of plant species in relation to the spread of greenhouses in a Mediterranean landscape, where habitat depletion is one of the main causes of biodiversity loss. For this purpose, presence records of the model species (Linaria nigricans, a endemic and threatened species) and the greenhouses, a dataset of environmental variables, and different only presence-based modelling algorithms (Bioclim, Domain, GARP, MaxEnt and ENFA) were used to build SDMs for L. nigricans as well as for greenhouses. To evaluate the models a modified approach of the area-under-curve ROC was applied. Combining the most accurate models, we generated an extinction-risk model of L. nigricans populations, which enabled us to assess the sustainability of the most threatened populations. Our results show that is possible to model greenhouses spreading as a “biological invasion”. The procedure explained and used in this work is quite novel, and offers an objective spatial criterion intended for the management of natural resources and for the conservation of the biodiversity in areas threatened by habitat depletion processes as particular as greenhouses expansion.

Patterns of endemic plants and biogeography of the Baetic high mountains (south Spain)

Abstract The largest number of Iberian endemic plant species and indeed one of the largest in Europe is found in the Baetic Mountains in the south of Europe (Spain), with mountain peaks up to 1,800 m. Our aim is to analyze the endemic plants and biogeographic patterns as a base for establishing priority areas for conservation and management. We present the complete floristic list of the 237 narrow endemics that inhabit these mountain regions. Asteraceae, Brassicaceae, Poaceae and Papilionaceae are families with the largest number of endemic species. The comparative analysis shows that the Baetic mountains are an important centre of endemism in the Mediterranean basin with a present degree of endemism of 28, 18%. Biogeographic patterns are first identified according to the development of the endemic plants on calcareous soils or siliceous soils, and next the phytogeographic subunits identified by different levels of endemism diversity. The abundance of endemic species in the Baetic mountains is explained by the geographical isolation together with its natural history.

Selection of an endemic flora reserve network and its biogeographical significance in the Baetic ranges (Southern Spain)

Abstract The Baetic mountains are a very important centre of plant diversity and endemicity. The current environmental legislation includes many of these localities. In order to assess the current reserves network and to propose a selection of protected areas, and to examine the biogeographic distinctiveness of that selection, we applied to the orophilous endemic flora a variety of algorithms (some of which were never used for Europe before) on the Baetic ranges. In order to preserve this natural heritage, it would be necessary to protect at least twelve massifs, considering the siliceous portion of Sierra Nevada as a great priority area. The most notable gaps in the legislation are the ranges of Gádor, Revolcadores and La Pandera. The selected localities were characterized by their great biogeographical distinctiveness. The distinctiveness of the obtained selections stresses their reliability and also emphasizes the suitability of the biogeographic researches of the flora of the Baetic ranges for conservation objectives.

Conservation status of the first known population of Polygala balansae in Europe.

We studied the natural history as well as the conservation status of the first-known population of Polygala balansae in Europe (Granada, SE Spain). In the study area, we located only one population occupying a small patch of 1920 m2, between 120 and 160 m a.s.l., with 246 mature individuals. The species is classified as Critically Endangered (CR), under the following criteria: severely fragmented, inferred continuous decline, small population size, and continuing decline inferred from the number mature individuals. The main threats over the population are: spreading subtropical tree-crops and encroachment of human settlements for tourist purposes, plus natural causes (drought, wild or human-mediated fire, limited dispersal, poor recruitment/ reproduction/regeneration, high juvenile mortality, low densities and restricted range). Finally, passive and active conservation measures are proposed in order to guarantee the survival of the species.

Designing conservation strategies to preserve the genetic diversity of Astragalus edulis Bunge, an endangered species from western Mediterranean region

Astragalus edulis (Fabaceae) is an endangered annual species from the western Mediterranean region that colonized the SE Iberian Peninsula, NE and SW Morocco, and the easternmost Macaronesian islands (Lanzarote and Fuerteventura). Although in Spain some conservation measures have been adopted, it is still necessary to develop an appropriate management plan to preserve genetic diversity across the entire distribution area of the species. Our main objective was to use population genetics as well as ecological and phylogeographic data to select Relevant Genetic Units for Conservation (RGUCs) as the first step in designing conservation plans for A. edulis. We identified six RGUCs for in situ conservation, based on estimations of population genetic structure and probabilities of loss of rare alleles. Additionally, further population parameters, i.e. occupation area, population size, vulnerability, legal status of the population areas, and the historical haplotype distribution, were considered in order to establish which populations deserve conservation priority. Three populations from the Iberian Peninsula, two from Morocco, and one from the Canary Islands represent the total genetic diversity of the species and the rarest allelic variation. Ex situ conservation is recommended to complement the preservation of A. edulis, given that effective in situ population protection is not feasible in all cases. The consideration of complementary phylogeographic and ecological data is useful for management efforts to preserve the evolutionary potential of the species.

Comunidades vegetales rupícolas y subrupícolas del sudeste ibérico (Sierra de Los Filabres)

La sierra de Los Filabres es una interesante encrucijada biogeografica donde existen grandes contrastes ambientales, produciendose muchos gradientes ecologicos. Tras una estratificacion territorial, se reconocieron los diversos habitats rupicolas y subrupicolas, donde fueron muestreadas mediante el metodo fitosociologico clasico las comunidades vegetales colonizantes. Como resultado se encontraron once fitocenosis diferentes pertenecientes a cinco clases fitosociologicas, donde destacan Teucrio-Kerneretum boissieri subas. alyssetosum cadevaliani, Cosentinio-Teucrietum freynii o Centrantho nevadensis-Sedetum brevifolii, y se describen como novedosas una comunidad de Saxifraga trabutiana y la asociacion Diantho broteroi-Launaetum laniferae.

High mountain psychro-xerophilous calcicolous pastures of the Iberian Peninsula:Minuartio-Poion ligulatae

A syntaxonomical review of theMinuartio-Poion ligulatae (Festuco hystricis-Ononidetea striatae) in the Iberian Peninsula, supported by numerical classification (complete linkage clustering) and ordination (correspondence analysis), is presented. Communities of psychro-xerophilous calcicolous plants occur in the high mountains and “parameras” of the south and central western Iberian Peninsula, areas which suffer from severe frosts. The data collected point to three large groups of communities: those of the chorological Carpetano-Ibérico-Leonesa Province; those of the Castellano-Maestrazgo-Manchega Province; and those of the Bética Province. Within the latter group, similarities and differences between the communities were analyzed and two new associations (Herniario boissieri-Festucetum hystricis andPimpinello gracilis-Festucetum nevadensis) were described. In addition, data clearly support the existence of a humidity-xericity gradient responsible for the distinction of the communities into different syntaxonomic units.

Rock climbing alters plant species composition, cover, and richness in Mediterranean limestone cliffs

Rock climbing is among the outdoor activities that have undergone the highest growth since the second half of the 20th century. As a result, cliff habitats, historically one of the least disturbed by human colonization worldwide, are facing more intense human pressure than ever before. However, there is little data on the impact of this activity in plant-communities, and such information is indispensable for adequate manager decision-making. The goal of this study was to determine the impact of rock climbing on plant communities in terms of cover, richness, and composition in relation to climbing intensity on typical Mediterranean limestone cliffs. Three rock-climbing sites were selected in the Baetic range (SE Spain), corresponding to qualitative categories of climbing frequentation: i)“low” (low frequentation with intermittent climbing), ii)“medium” (high frequentation without overcrowding), and iii) “high” (high frequentation with overcrowding). Within each site, we selected climbing routes and adjacent areas free of climbing, then we carried out a photoplot-based sampling by rappelling. We analysed the images to calculate: richness, species cover, and total cover. This study shows that rock climbing negatively affected the cliff plant community at all three study sites. A significant decrease in plant cover, species richness and a shift in the community composition were recorded for climbed areas, the cover being the variable most sensitive to rock climbing. Impact observed proved to be related to the frequentation level. Low-frequentation sites, with usually more specialized climbers, underwent relatively mild damages, whereas at high frequentation sites the impact was severe and the conservation of the species, especially rare ones, became jeopardized. Our study is the first one available to investigate climbing impact on plant communities in Mediterranean areas, but more research on the impact of rock climbing is needed to assess the regulation of this activity. Regarding management guidelines, we propose a management guideline protocol to evaluate climbing routes and design: i) “Sites free of climbing”, ii) “Strictly regulated climbing routes”, iii) “Mildly regulated climbing routes”, or iv) “Free climbing routes”.

Morphometric study of the complex Moehringia sect. Pseudomoehringia McNeill from the western Mediterranean

Abstract Moehringia. sect. Pseudomoehringia McNeill is endemic to the western Mediterranean, having its origin and diversification centre in the Iberian Peninsula and mountains of northern Morocco. Both the relationship with the genus Arenaria as well as the taxonomy within the section have been largely controversial. To disentangle these issues, we conducted a morphometric study using herbarium material. We measured 12 relevant morphological traits from 148 selected herbarium sheets. Data were analyzed using different statistical methods: general linear models, multiple factorial analysis and linear discriminant analysis. We found significant differences between Arenaria balearica and the rest of the genus Moehringia taxa. Within this genus, we identified three well-discriminated species: Moehringia fontqueri, M. glochidisperma and M. intricata. Within M. intricata complex, we discerned virtually no differences amongst most of the subspecies (intricata, giennensis and tejedensis) with the exception of subsp. castellana. We propose: (i) to maintain A. balearica separate from Moehringia sect. Pseudomoehringia; (ii) to consider three species in the section Pseudomoehringia: M. fontqueri, M. glochidisperma and M. intricata; (iii) to recognize only two subspecies within M. intricata complex: subsp. intricata and subsp. castellana. To clarify the taxonomy of this threatened group is of great interest because it might help to prioritize conservation measures.