Aportación al conocimiento de los líquenes epífitos de Pinus halepensis, P. nigra, P. pinaster y P. sylvestris en la Península Ibérica

Se presenta el estudio de la diversidad liquénica epífita en diferentes pinares de la Península Ibérica. Se han estudiado 84 pinares (37 de Pinus nigra, 6 de P. halepensis, 17 de P. pinaster y 24 de P. sylvestris). El total de especies liquénicas herborizadas es de 170. Se han identificado 49 especies sobre P. halepensis, 77 sobre P. pinaster, 79 sobre P. sylvestris y 123 líquenes sobre P. nigra. En los pinares de Pinus sylvestris, situados en zonas más continentales, domina una flora de líquenes, en algunos casos, similar a la de los bosques de coníferas del norte de Europa. El elemento de amplia distribución es el más abundante. El porcentaje de especies de distribución submediterránea-mediterránea es más elevado a medida que descendemos en altitud y latitud, mientras que el porcentaje de especies boreales es mayor a medida que nos situamos en cotas más altas y zonas más septentrionales.A study about the lichenic epiphytic diversity on different pine forests in the Iberian Peninsula is presented. A total of 84 pine forests are studied (37 of Pinus nigra, 6 of P. halepensis, 17 of P. pinaster and 24 of P. sylvestris). The number of collected species is 170, 49 species on P. halepensis, 77 on P. pinaster, 79 on P. sylvestris and 123 lichens on P. nigra. Lichens on Pinus sylvestris in more continental areas were similar to the species growing in conifer forests of Northern Europe. The widespread element is the most abundant. The percentage of submediterranean- mediterranean lichen species is higher at lower latitude and altitude, whereas boreal species are most frequent at higher latitude and altitude

Valoración de la diversidad de líquenes epífitos en bosques de quercíneas mediante un nuevo índice liquénico (IDLE). Aplicación a la Red Natura 2000

Se propone un nuevo índice de diversidad liquénica epifítica (IDLE) que incorpora valores de riqueza, frecuencia y calidad. El estudio se realizó sobre 346 manchas de bosque distribuidas por todo el territorio de Castilla-La Mancha. Se seleccionaron variables relacionadas con la orografía y paisaje, con la estructura y manejo del bosque y variables climáticas. Mediante Modelos Lineares Generalizados (GLMs) evaluamos el efecto de cada una de ellas sobre los valores de IDLE. Los resultados indican que la diversidad de líquenes está principalmente relacionada con la intensidad de manejo, cobertura arbórea y edad del bosque. Con los resultados obtenidos se establecieron cinco clases de valores cuantitativos a los que relacionamos con una valoración cualitativa de diversidad: muy alta, alta, moderada, baja y muy baja. Posteriormente analizamos la coincidencia de las manchas con valores de diversidad “muy alta” y “alta” con los espacios que van a conformar la Red Natura 2000 en Castilla-La Mancha y comprobamos que la mayoría de ellos quedarían integrados en dicha Red.A new diversity index for epiphytic lichens (IDLE) is proposed, incorporating richness, frequency and quality values. The study is developed in 346 forests distributed along Castilla-La Mancha region. Environmental variables were selected related to topography and landscape, structure and management of the forests and climate. General Linear Models (GLMs) were used to study the effect of the different environmental variables on the IDLE. The results indicate that the lichens diversity is mainly related to the management intensity, cover and age of forests. Moreover, we established 5 quantitative categories linked to a qualitative assessment of the lichens diversity: very high, high, moderate, low and very low. In relation to the success of the Natura 2000 network, our results show that the capability of this network to protect the forests with the higher values of lichens diversity seem to be guarantied

Diversidad liquénica de las islas Chafarinas, España

Se presentan los resultados florísticos sobre el estudio de los líquenes que habitan en el archipiélago de las islas Chafarinas. En total, se han identificado 92 especies pertenecientes a 36 géneros. De ellas, 15 son epífitas, 27 están ligadas a superficies calcáreas y 54 especies viven sobre andesitas y/o basaltos. Los afloramientos calcáreos son colonizados por especies nitrófilas, debido al impacto humano y a la nitrificación procedente de los depósitos de guano. La diversidad de líquenes epífitos es muy reducida, debido al carácter residual de los forófitos. La composición de las comunidades silicícolas varian en función del hábitat que ocupen y de la situación, altitud y topografía de los acantilados. La isla Congreso alberga la mayor riqueza de especies (79 especies), mientras que en las islas Isabel II y Rey se han contabilizado 58 y 46 especies respectivamente. Además, se destaca la importancia de algunos enclaves del archipiélago por albergar una mayor riqueza y diversidad, la presencia de un mayor número de especies anitrófilas y de especies con un área de distribución más restringida a nivel mundial.A catalogue of lichens from Chafarinas Islands is presented. A total number of 36 genera and 92 species are reported. Mostly species were growing on siliceous rocks (andesite or basalts), 27 were found on calcareous rocks and only 15 were epiphytic lichens due to the shortage of phorophytes. Nitrophilous species were abundant on calcareous rocks due to the human impact and the nutrients received from bird droppings. The composition of silicicolous communities kept relation with the habit colonized on the rocks and with the situation, altitudinal rank and the topography of the cliffs. Cogreso Island contain the highest lichen richness (79 species), whilst the number of lichens from the Isabel II and Rey Islands were 58 and 46 species respectively. Finally, we emphasize about three localities that contain the highest lichen richness and diversity, the presence of a high number of non-nitrophilous species and taxa with a scatter world distribution

Remnants fragments preserve genetic diversity of the old forest lichen Lobaria pulmonaria in a fragmented Mediterranean mountain forest

Fragmentation represents a serious threat to biodiversity worldwide, however its effects on epiphytic organisms is still poorly understood. We study the effect of habitat fragmentation on the genetic population structure and diversity of the red-listed epiphytic lichen, Lobaria pulmonaria, in a Mediterranean forest landscape. We tested the relative importance of forest patch quality, matrix surrounding fragments and connectivity on the genetic variation within populations and the differentiation among them. A total of 855 thalli were sampled in 44 plots (400m2) of 31 suitable forest fragments (beeches and oaks), in the Sierra de Ayllón in central Spain. Variables related to landscape attributes of the remnant forest patches such as size and connectivity and also the nature of the matrix or tree species had no significant effects on the genetic diversity of L. pulmonaria. Values of genetic diversity (Nei's) were only affected by habitat quality estimated as the age patches. Most of the variation (76%) in all populations was observed at the smallest sampled unit (plots). Using multiple regression analysis, we found that habitat quality is more important in explaining the genetic structure of the L. pulmonaria populations than spatial distance. The relatively high level of genetic diversity of the species in old forest patches regardless of patch size indicates that habitat quality in a highly structured forest stand determines the population size and distribution pattern of this species and its associated lichen community. Thus, conservation programmes of Mediterranean mountain forests have to prioritize area and habitat quality of old forest patche

Fine spatial pattern of an epiphytic lichen species is affected by habitat conditions in two forest types in the Iberian Mediterranean region

Persistence and abundance of species is determined by habitat availability and the ability to disperse and colonize habitats at contrasting spatial scales. Favourable habitat fragments are also heterogeneous in quality, providing differing opportunities for establishment and affecting the population dynamics of a species. Based on these principles, we suggest that the presence and abundance of epiphytes may reflect their dispersal ability, which is primarily determined by the spatial structure of host trees, but also by host quality. To our knowledge there has been no explicit test of the importance of host tree spatial pattern for epiphytes in Mediterranean forests. We hypothesized that performance and host occupancy in a favourable habitat depend on the spatial pattern of host trees, because this pattern affects the dispersal ability of each epiphyte and it also determines the availability of suitable sites for establishment. We tested this hypothesis using new point pattern analysis tools and generalized linear mixed models to investigate the spatial distribution and performance of the epiphytic lichen Lobaria pulmonaria, which inhabits two types of host trees (beeches and Iberian oaks). We tested the effects on L. pulmonaria distribution of tree size, spatial configuration, and host tree identity. We built a model including tree size, stand structure, and several neighbourhood predictors to understand the effect of host tree on L. pulmonaria. We also investigated the relative importance of spatial patterning on the presence and abundance of the species, independently of the host tree configuration. L. pulmonaria distribution was highly dependent on habitat quality for successful establishment, i.e., tree species identity, tree diameter, and several forest stand structure surrogates. For beech trees, tree diameter was the main factor influencing presence and cover of the lichen, although larger lichen-colonized trees were located close to focal trees, i.e., young trees. However, oak diameter was not an important factor, suggesting that bark roughness at all diameters favoured lichen establishment. Our results indicate that L. pulmonaria dispersal is not spatially restricted, but it is dependent on habitat quality. Furthermore, new spatial analysis tools suggested that L. pulmonaria cover exhibits a distinct pattern, although the spatial pattern of tree position and size was random

The anchorage of the Platja de la Vila (Vila Joiosa, Alicante): the classical period

El fondeadero de la Platja de la Vila presenta una utilización continuada al menos entre los siglos II a.C. y V d.C., y a partir del s. XIV hasta los años veinte del presente. Estudiamos aquí los materiales de época clásica, obtenidos durante los trabajos de prospección subacuática desarrollados por nuestro equipo, a los que se añade las piezas extraídas por el club de buceo local. Se presta una especial atención a la interrelación con el contexto arqueológico de tierra.Le mouillage de la Platja de la Vila présente une utilisation continue, tout au moins, entre le IIème s. av. J-C et le Vème 5 ap. J-C, et a partir du XIVème s. jusqu'aux années 20 du présent. On étudie dans cet article-ci les matériaux d'époque classique qui ont été obtenus pendant les travaux de prospection dévéloppés par notre équipe, mais aussi les pieces tirées de la mer par le club local de plongée. On a fait une attention spéciale à la relation avec le contexte archélogique de terre

Abiotic, present-day and historical effects on species, functional and phylogenetic diversity in dry grasslands of different age.

Many grasslands have disappeared over the last century as a result of anthropogenic land use intensification, while new patches are emerging through abandonment of arable fields. Here, we compared species (SD), functional (FD) and phylogenetic (PD) (alpha) diversity among 272 dry grassland patches of two age-classes: old and new, with the new patches being dry grasslands established on previous intensively managed fields during the last 30 years. We first compared SD, FD and PD, between patches of different age. Then, we performed generalized linear models to determine the influence of abiotic, present-day and historical landscape configuration variables on SD, FD and PD. By measuring abiotic variables, we explained the effect of environmental filtering on species diversity, whereas the present-day and historical landscape configuration variables were included to describe how the spatial and temporal configuration of the patches influence patterns of species. Finally, we applied partial regressions to explore the relative importance of abiotic, present-day and historical variables in explaining the diversity metrics and how this varies between patches of different ages. We found higher SD in the old compared to the new patches, but no changes in FD and PD. SD was mostly affected by abiotic and present-day landscape configuration variables in the new and the old patches, respectively. In the new patches, historical variables explained variation in the FD, while present-day variables explained the PD. In the old patches, historical variables accounted for most of the variation in both FD and PD. Our evidence suggests that the relative importance of assembly processes has changed over time, showing that environmental filtering and changes in the landscape configuration prevented the establishment of species in the new patches. However, the loss of species (i.e. SD) is not necessarily linked to a loss of functions and evolutionary potential