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Aims Global change projections predict biodiversity changes and increased drought intensity in the Mediterranean Basin in the decades to come. This will presumably affect plant performance, plant community composition and ecosystem functioning. Shrublands are widespread in the Mediterranean area, yet we have no clear understanding of shrubland responses to the combined effects of increased drought and changes in plant diversity. Location Natural Mediterranean shrubland, Marseille, south France. Methods A rainfall manipulation experiment was conducted to examine the performance of four dominant shrub species in response to increased drought. The study assemblages spanned a gradient of four shrub richness levels (mono-, bi-, tri- and tetra-specific plant mixtures) and 15 different shrub combinations. Throughout the 2 yr of non-destructive experiments (2012-2014), we measured plant litter fall, stand necromass and plant cover of the four dominant plant species: Cistus albidus, Quercus coccifera, Rosmarinus officinalis and Ulex parviflorus. Results Increasing shrub richness levels in the plant community led to higher litter production by all four species and a decrease in dry shoots for Quercus and Ulex. Shrub species responses were affected by the rain exclusion treatment, but the effects were mainly dependent on shrub richness level. In mono-specific plots, aggravated drought conditions led to a decrease in litter fall of Cistus, Rosmarinus and Ulex and an increase in necromass of all four species. In general, these negative drought effects disappeared as number of shrub species in the community increased. Under rain exclusion treatment, Rosmarinus cover decreased in mono-specific plots whereas Quercus cover increased in bi-specific plots and Rosmarinus cover increased in tetra-specific plots. We observed two drought tolerance patterns, with Quercus and Rosmarinus being more tolerant species and Ulex and Cistus less tolerant. Conclusions The magnitude of drought effects on shrub performance is species-specific, and plant species combination-dependent. High shrub richness levels modulate the negative impacts of aggravated drought conditions. Our results point to a probable shift of interspecific relationships in response to water shortage. As drought impacts are not mediated in low-diversity communities, species-specific responses to drier conditions could lead to shifts in plant community composition favouring the most drought-resistant species, i.e. Quercus and Rosmarinus. Maintaining high diversity appears critical to mediate drought effects for less resistant species ( Cistus and Ulex in our study). [ABSTRACT FROM AUTHOR]

Floristic and vegetation analysis in seven Mediterranean landslides led to the understanding of the successional processes occurring in different landslide disturbed sectors. Our study showed that in landslides that occurred between 1996 and 2010 there is a clear differentiation between the three main landslide sectors (scarp, main body and foot) concerning floristic composition, vegetation structure, floristic richness, successional processes and plant functional type. Additional differences were found between landslide areas and undisturbed agricultural areas adjacent to landslides. In this study 48 floristic relevés were made using a stratified random sampling design. The main landslide body exhibits the highest floristic richness whereas the landslide scarp has the lowest coverage rate and the highest presence of characteristic species from ruderal and strongly perturbed habitats. Finally, the landslide foot shows a late stage in the succession (maquis or pre-forest stage) with a high dominance of vines. We further discuss the importance of landslides as reservoirs of biodiversity especially for Mediterranean orchids. [ABSTRACT FROM AUTHOR]

Landscape structure is known to critically affect biodiversity. However, although the multi-facetted character of biodiversity is widely recognized, few studies have linked landscape spatial pattern and history simultaneously to multiple facets (taxonomic, functional, and phylogenetic) and spatial components (α, β, and γ) of plant diversity. We set out to reveal whether landscape parameters have specific effects on the separate diversity facets and components of plant diversity at a patch scale on coastal dune landscapes of Central Italy. For each landscape patch, we computed a set of patch-based metrics relying on multi-temporal land-cover maps. Based on a database of plant community plots, on functional traits from field measurements and on a dated phylogenetic tree, we calculated taxonomic (TD), functional (FD), and phylogenetic diversity (PD) within each patch at α, β, and γ level. Diversity measures were then related to the landscape metrics via linear mixed-effect models. Landscape pattern and transformations affected TD only moderately in coastal dune ecosystems. We found much stronger and contrasted effects on FD and PD. FD increased in patches surrounded by human-dominated habitats; PD was higher in fragmented patches, particularly in the Mediterranean macchia. Moreover, landscape pattern affected differently the single communities, the turnover among communities and the pool of species within the patch (α, β, and γ components). Our results call for the combined inclusion of FD and PD and their partitions into ecological analyses, being TD too crude to capture the comprehensive and contrasted response of plant diversity to landscape spatial pattern. [ABSTRACT FROM AUTHOR]

The composition and structure of riparian vegetation are linked to the natural hydrological variability and variation of environmental parameters in several spatial scales. The objective of this study is to determine the relationship between the spatial distribution of the woody riparian vegetation and the variation in the riverbank topographic gradient, verifying whether this variation was significant between species and/or growth categories. Specifically, our research examined the location of the woody species with respect to the thalweg along two reaches of the Jarama River in Central Spain. The positioning variables of each individual and distance and elevation above the thalweg were evaluated for four growth categories using statistical analysis. This study revealed that the positioning of the species along reaches is not random and differs with the species and growth categories. In addition, groups of species were specified in the different growth categories using similar positioning patterns with respect to the thalweg. Examples of similar groups of species in a specifically growth category were as follows: Alnus glutinosa-Salix alba-Salix fragilis for one reach and Alnus glutinosa-Populus nigra-Salix alba-Salix salviifolia for the other one. Topographical preference ranges of the riparian species and groups of the Jarama River were also obtained. The integration of data relative to the distribution of species along the topographic gradient can be very useful in identifying species with a preference for specific locations and can also contribute to the success of the measures adopted to restore these frequently highly degraded environments. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background and Aims Many studies have analysed the mechanisms that determine plant coexistence in standing vegetation, but the determinants of soil seed bank species assemblies have rarely been studied. In gypsum soil communities, aerial vegetation and seed banks are tightly connected in space and time, but the mechanisms involved in their organization may differ. The aim of this study is to understand the relative importance of biotic and abiotic factors controlling soil seed bank composition and structure. Methods Persistent and complete (i.e. persistent plus transient) soil seed banks were investigated at two spatial scales in a very species-rich semi-arid community dominated by annuals. A water addition treatment equivalent to 50% annual increase in average precipitation (abiotic factor) was applied for two consecutive years, and the relationships of the soil seed bank to the biological soil crust (BSC), above-ground vegetation and the presence of Stipa tenacissima tussocks (biotic factors) were simultaneously evaluated. Key Results As expected, the standing vegetation was tightly related to seed abundance, species richness and composition in both seed banks. Remarkably, BSC cover was linked to a decrease in seed abundance and species richness in the persistent seed bank, and it even determined complete seed bank composition at the fine spatial scale. However, this effect disappeared at coarser scales, probably because of the high spatial heterogeneity induced by BSCs. In contrast to findings on standing vegetation, Stipa and the irrigation treatment for two consecutive years had no effect on soil seed banks. Conclusions Soil seed bank assemblies in our semi-arid plant community were the result of above-ground vegetation dynamics and of the direct filtering processes on seed fate operated by the spatially heterogeneous BSCs. Cover of BSCs was negatively correlated with seed abundance and species richness, and affected seed species composition in the soil. Changes in species composition and enrichment when the BSC cover is low suggest that BSCs promote a fine scale niche differentiation in the soil seed bank and thereby potentially enhance species coexistence and high species diversity in these communities. [ABSTRACT FROM AUTHOR]

Under Mediterranean conditions, drought and fire are prevalent disturbances that play a fundamental role in the distribution, organization and evolution of ecosystems. Reforestation programs were carried out in degraded areas by planting pines. Presently, the spontaneous regeneration of other species is scarce and species diversity is poor. Introducing woody resprouter species under pine forests would increase species diversity and ecosystem resilience to cope with different types of disturbances, such as wildfires. In this study, we investigated the survival, growth and functional responses of six Mediterranean trees and shrub resprouter species planted under pine forests. Experiments were done in a dry Mesomediterranean climate. Seedlings from a wide array of early to late successional trees and shrub species were outplanted in different pine densities, low, medium and high, which corresponded to 22%, 48% and 62% of the maximum sunlight received, respectively. The time course of survival and growth (height and basal diameter) were analyzed for 3 years after outplanting. Survival was higher than 78%, although differences between species and pine densities were found. Seedling growth also reflected different interactions among introduced seedlings and density of pines. Water use efficiency of species based on isotopic determinations (δ 13 C and δ 18 O) differed between densities and species according to functional groups. These results have relevant implications for the management and restoration of fire-prone Mediterranean pine forests. [ABSTRACT FROM AUTHOR]

Community assembly rules have been extensively studied, but its association with regional environmental variation and land use history remains largely unexplored. Land use history might be especially important in Mediterranean forests, considering their historical deforestation and recent afforestation. Using forest inventories and historical (1956) and recent (2000) land cover maps, we explored the following hypotheses: 1) woody species assembly is driven by environmental factors, but also by historical landscape attributes; 2) recent forests exhibit lower woody species richness than pre-existing due to the existence of colonization credits; 3) these credits are modulated by species' life-forms and dispersal mechanisms. We examined the association of forest historical type (pre-existing versus recent) with total species richness and that of diverse life-forms and dispersal groups, also considering the effects of current environment and past landscape factors. When accounting for these effects, no significant differences in woody species richness were found between forest historical types except for vertebrate-dispersed species. Species richness of this group was affected by the interaction of forest historical type with distance to coast and rainfall: vertebrate-dispersed species richness increased with rainfall and distance to the coast in recent forests, while it was higher in dryer sites in pre-existing forests. In addition, forest historical types showed differences in woody species composition associated to diverse environmental and past landscape factors. In view of these results we can conclude that: 1) community assembly in terms of species richness is fast enough to exhaust most colonization credit in recent Mediterranean forests except for vertebrate-dispersed species; 2) for these species, colonization credit is affected by the interplay of forest history and a set of proxies of niche and landscape constraints of species dispersal and establishment; 3) woody species assemblage is mostly shaped by the species' ecological niches in these forests. [ABSTRACT FROM AUTHOR]

The Hyperspectral Infrared Imager (HyspIRI) is a proposed satellite mission that combines a 60 m spatial resolution Visible-Shortwave Infrared (VSWIR) imaging spectrometer and a 60 m multispectral thermal infrared (TIR) scanner. HyspIRI would combine the established capability of a VSWIR sensor to discriminate plant species and estimate accurate cover fractions with improved Land Surface Temperatures (LST) retrieved from the TIR sensor. We evaluate potential synergies between Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) maps of dominant plant species and mixed species assemblages, fractional cover, and MODIS/ASTER Airborne Simulator (MASTER) LST utilizing multiple flight lines acquired in July 2011 in the Santa Barbara, California area. Species composition and green vegetation (GV), non-photosynthetic vegetation (NPV), impervious, and soil cover fractions were mapped using Multiple Endmember Spectral Mixture Analysis with a spectral library derived from 7.5 m imagery. Temperature-Emissivity Separation (TES) was accomplished using the MASTER TES algorithm. Pixel-based accuracy exceeded 50% for 23 species and land cover classes and approached 75% based on pixel majority in reference polygons. An inverse relationship was observed between GV fractions and LST. This relationship varied by dominant plant species/vegetation class, generating unique LST–GV clusters. We hypothesize clustering is a product of environmental controls on species distributions, such as slope, aspect, and elevation as well as species-level differences in canopy structure, rooting depth, water use efficiency, and available soil moisture, suggesting that relationships between LST and plant species will vary seasonally. The potential of HyspIRI as a means of providing these seasonal relationships is discussed. [ABSTRACT FROM AUTHOR]

In this paper ten names in Andryala are lectotypified. All are either accepted species or subspecies names in a forthcoming taxonomic revision of the genus. [ABSTRACT FROM AUTHOR]

Mediterranean-type ecosystems (MTEs) are remarkable in their species richness and endemism, but the processes that have led to this diversity remain enigmatic. Here, we hypothesize that continent-dependent speciation and extinction rates have led to disparity in diversity between the five MTEs of the world: the Cape, California, Mediterranean Basin, Chile, and Western Australia. To test this hypothesis, we built a phylogenetic tree for 280 Rhamnaceae species, estimated divergence times using eight fossil calibrations, and used Bayesian methods and simulations to test for differences in diversification rates. Rhamnaceae lineages in MTEs generally show higher diversification rates than elsewhere, but speciation and extinction dynamics show a pattern of continent-dependence. We detected high speciation and extinction rates in California and significantly lower extinction rates in the Cape and Western Australia. The independent colonization of four of five MTEs may have occurred conterminously in the Oligocene/Early Miocene, but colonization of the Mediterranean Basin happened later, in the Late Miocene. This suggests that the in situ radiations of these clades were initiated before the onset of winter rainfall in these regions. These results indicate independent evolutionary histories of Rhamnaceae in MTEs, possibly related to the intensity of climate oscillations and the geological history of the regions. [ABSTRACT FROM AUTHOR]

The present brief and selective review focuses on a set of invasive alien aquatic plant species (notably the 21 listed by the European and Mediterranean Plant Protection Organisation, i.e., five A2 species, 11 invasive, 2 in the Observation List, 1 in the Alert List, 2 noteworthy), on definitions in use, on introduction pathways, and ecological effects, although the social and economic effects of freshwater invaders can be diverse and substantial. Legislation, literature, and scientific research dealing with plant invasions in inland waters often merge different types of invasive plant species and invaded habitats, as there are some overlappings between the concepts of macrophyte, aquatic plants, inland waters, wetlands, and riparian habitats. Freshwater ecosystems may well be the most endangered ecosystems in the world. Countless aquatic plants have been introduced in Europe and in the Mediterranean region, either deliberately because they were thought to be ornamental or otherwise desirable, or accidentally as releases from aquaria, dumping from water gardens, or contaminants. The escape of alien plants from managed environments is also frequent. Aquatic invaders have strong negative impacts on native biodiversity and many different impacts are reported in the literature for Europe and worldwide. Plant invasions in inland waters may be considered as one of a syndrome of factors that characterize degraded aquatic ecosystems. There are a number of risk analysis, impact assessment, ranking systems, decision trees, and prioritization methods available throughout Europe and the EPPO region, but the lack of a common framework for assessing the risks posed by invasive alien aquatic species is seen as a key gap. Successful management should include prevention, habitat restoration, dedicated risk assessment, prioritization, awareness raising, dedicated legislation, collaboration between different stakeholders, development of codes of conduct with the horticultural sector, and prohibiting the sale, purchase, and intentional release of some species in the wild. Actions to protect the European and Mediterranean inland waters from plants invasions are urgently needed and could provide overarching benefits. [ABSTRACT FROM AUTHOR]

Cortinariusis one of the most widespread macrofungal genera. Although Mediterranean basin is considered a biodiversity hotspot, very few studies have addressed the presence and importance ofCortinariusspecies in such area. Surveys were carried out in Liguria (NW Italy) in different habitats characterized by the presence ofQuercus ilex. Altogether 67 taxa were observed: 49 of them are new records for Liguria while 23 represent new records for Italy. In addition, we report the distinguishing characters and ecological traits of the species which are also rare in Europe. [ABSTRACT FROM AUTHOR]

ABSTRACT Previous research has developed a method to assess the impact of check dams on riparian vegetation and related river bed sediment size with vegetation coverage and development. On the basis of this knowledge, this paper aims to investigate the effects on riparian species diversity induced by 32 check dams in four torrent headwaters of Southern Italy. Species richness and composition of riparian vegetation in the active channel were surveyed upstream and downstream of each check dam and in intermediate (less disturbed) sites. Furthermore, links between hydromorphological processes and vegetation diversity were analysed. The identified differences in species diversity seem to be related to the morphological adjustments of the channel after the installation of check dams. These fluvial morphological adjustments introduced variations to the flood depth and frequency of the riparian areas creating new riparian conditions. Higher species richness and evenness were observed upstream of check dams, where alien species prevail over native ones in new habitats on the sedimentation wedge behind the dam. Conversely, downstream of check dams, where the boundary of the inundated area moves down towards the thalweg (due to incision processes after check dam installation), riparian vegetation tends to assume a terrestrial character, losing some herbaceous species of the riparian environment. This research confirms that the discontinuity in the fluvial environment caused by check dams induces morphological adjustments that can be translated in new riparian conditions for the establishment of vegetation, affecting the ecological aspects and species diversity of riparian habitats. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Fire has been proposed as a factor explaining the exceptional plant species richness found in Mediterranean regions. A fire response trait that allows plants to cope with frequent fire by either reseeding or resprouting could differentially affect rates of species diversification. However, little is known about the generality of the effects of differing fire response on species evolution. We study this question in the Restionaceae, a family that radiated in Southern Africa and Australia. These radiations occurred independently and represent evolutionary replicates. We apply Bayesian approaches to estimate trait-specific diversification rates and patterns of climatic niche evolution. We also compare the climatic heterogeneity of South Africa and Australia. Reseeders diversify faster than resprouters in South Africa, but not in Australia. We show that climatic preferences evolve more rapidly in reseeder lineages than in resprouters and that the optima of these climatic preferences differ between the two strategies. We find that South Africa is more climatically heterogeneous than Australia, independent of the spatial scale we consider. We propose that rapid shifts between states of the fire response trait promote speciation by separating species ecologically, but this only happens when the landscape is sufficiently heterogeneous. [ABSTRACT FROM AUTHOR]

Thymus is one of the most critical genera of the Euro-Mediterranean flora and most of its taxa are in need of typifica-tion. During a preliminary study on the taxonomy of this genus in the Mediterranean area, several names turned out to be not yet typified. In order to fix their applications, nomenclatural types for 18 names within the genus Thymus are here designated. The new combination Thymus praecox subsp. parvulus (Lojac.) Bartolucci, Peruzzi & N.G. Passai, is also proposed. [ABSTRACT FROM AUTHOR]

Abstract: The most pervasive threats to biological diversity are directly or indirectly linked to the road networks. For this reason, over the last few decades, interest in the study of the ecological characteristics of the edges associated with roads has increased. This work aims to investigate the effect of roads as a human-induced disturbance on the plant diversity in two managed Mediterranean forest sites, focusing on the responses of plants species richness, evenness, composition and taxonomic diversity. A stratified random sampling was performed in two protected areas located in Tuscany, Central Italy. The species richness, composition and abundance were measured in 53·20 × 20 m plots. Ordinary Least Square and quantile regressions were used to study the effect of the roads on species richness, evenness and taxonomic distinctness, and redundancy analysis was used to examine the species composition. Generalized linear models in conjunction with an Information Criterion-based approach to model selection were used to test the role of road distance in the structure of forest plant biodiversity. Our findings indicated a clear relationship between road distance and different plant biodiversity facets, which showed its maximum effect in the first 0–20 m forest-to-road segment and a mitigation after the 200 m threshold. Furthermore, the presence and abundance of many key forest species, such as Fagus sylvatica and Abies alba, were influenced more by the road distance than by other environmental gradients. The few remnants of core forest habitats in the Mediterranean basin highlight the need to recognize that road construction and maintenance have several ecological implications and accordingly require long-term monitoring programs. [Copyright &y& Elsevier]

Abstract: Disturbance intensity and metapopulation dynamics are among the theoretical mechanisms explaining species coexistence at the local and landscape scale. Both mechanisms might interact, so that the consequences of local disturbances might depend on long distance dispersal events. In this study we examined whether the richness of tree species potentially able to colonize a locality from the surroundings was associated with the tree species richness observed in that locality, and/or with the response of that richness to partial harvesting. The study was located in a Mediterranean region in central Spain where partially harvested forests had been found to have more tree species than unmanaged forests. We used a top-down hierarchical modeling structure to account for the effect of other factors such as climate, lithology and amount of forest cover at the landscape scale. Species richness of trees was strongly associated to annual precipitation, and was maximized at intermediate rainfall levels. Under homogeneous climate and lithological conditions, the composition and connectivity of seed sources in the landscape seemed to play a more relevant role explaining tree species richness than the amount of forest habitat in the surroundings. Particularly, higher species richness was observed in forest stands susceptible of receiving a higher diversity of seed fluxes. Patterns in the response of species richness to partial harvesting were less clearly explained by differences in the diversity of potential seed fluxes, but time lags in the responses, or differences in the proportion of shade-tolerant species in the landscape could mediate this interaction. Stronger importance of the amount of forest habitat and diversity of potential seed fluxes may be masked by their correlations with precipitation gradients in the study area. Our results emphasize the need of a wide scale approach to forest planning in order to be able to account for and to influence determinant processes of diversity patterns from the stand to the landscape levels. [Copyright &y& Elsevier]

Abstract: Arthropod assemblages (Isopoda Oniscidea, Chilopoda, Coleoptera Carabidae) were studied in three 20-year-old reforestations with native oak species (holm-oak Quercus ilex, Turkey-oak Quercus cerris, and downy-oak Quercus pubescens) and in a natural mixed oak forest (Q. cerris and Quercus frainetto) in Latium (central Italy). The three reforested areas had been previously used for agricultural purposes. Samples were collected monthly by pitfall traps for a period of 1year (March 2009–February 2010). Structural parameters and the arthropod assemblage compositions of the four studied areas were compared. The effects of the different forest types and the influence of environmental variables on the activity density of each species were analyzed, with particular emphasis to forest species. Contrary to centipedes and ground beetles, woodlice showed lower values of richness, diversity and equitability in reforestations than in the natural forest. According to Canonical Correspondence Analysis, forest species of woodlice and centipedes resulted mainly associated with forests characterized by a high structural heterogeneity (natural forest and reforestation with Q. pubescens). In these two forests the activity density of centipede forest species is mainly influenced by the coverage of both shrub and leaf litter layer, and woodlice forest species only by the coverage of the latter. The ground beetle forest species were mainly associated with forests characterized by low structural heterogeneity and an almost total closure of the canopy throughout the year (reforestation with Q. ilex). However, some ground beetle forest species are present also in the natural forest. Our results suggest that reforestations with different native broadleaf species belonging to the local “potential” vegetation can contribute to the conservation of the diversity of forest arthropod assemblages in the extremely fragmented agricultural landscape of the middle Tyrrhenian area. [Copyright &y& Elsevier]

The variation of riparian plant species composition along a river according to lithological features, forming more or less discrete plant assemblages, was tested using multivariate and univariate analyses. Moreover, Sørensen's index was applied to examine similarity between geological and floristic groups, and the Wilson–Shmida index to investigate species turnover. The analyses were based on field data recorded along a Mediterranean river (Rio Santa Lucia, Sardinia, Italy), where the morphology is influenced by the bedrock-alluvial transition. The results obtained from the various analytical techniques were in close agreement, and underlined that the lithological types exerted an important influence on the distribution and richness (peak in the medium and the upper river part) of riparian plants, but also in their life forms (woody species and hemicryptophytes). The distribution patterns of species along the river suggested that primary drivers in the organization of the riparian plant communities were lithological types, geomorphology and altitude. Moreover, the bedrock-alluvial transition marked the highest species turnover, linked also to a different degree of human disturbance. The results of the present study indicate that the bedrock/alluvial influence is an integral component of the patch structure, which strongly influences riparian plant distribution patterns in a Mediterranean environment. [ABSTRACT FROM PUBLISHER]

Field boundaries are expected to support the maintenance of biodiversity in agroecosystems, since they provide the habitat for a range of plant species. However, plant diversity in field boundaries has decreased substantially in recent decades. This pattern is generally linked with the intensification of agricultural land use at field and landscape level. Therefore, we aimed to test the effect of farming management (field and boundary management), boundary structure (width and habitat assemblage considering the Mediterranean grassland element), and landscape heterogeneity on plant species richness of field boundaries. Plants were recorded along 30 field boundaries next to organic fields and 30 next to conventional fields located in 15 agrarian localities of NE Iberian Peninsula along a gradient of landscape complexity. A total of 517 plant species were identified in the 60 field boundaries. We recorded 162 species (31%) catalogued as rare, very rare or extremely rare in the flora of the Catalan Countries. Our results showed the importance of landscape heterogeneity, field management and habitat assemblage, since they were found to be the most influential variables for plant species richness; whereas boundary width and boundary management were seen to contribute less to explaining plant diversity. Accordingly, agri-environmental schemes should be designed to promote organic farming and maintain the structure of the landscape mosaic in order to benefit plant diversity in field boundaries in the Mediterranean region. [ABSTRACT FROM AUTHOR]

Recent studies showed that disturbances and water availability determine the richness among plants with different post-fire strategies of Mediterranean-type ecosystems. The aim of this study was to determine whether or not the scale of analysis has an influence on the effects of these factors and, therefore, on the segregation of the dominant post-fire strategies, obligate seeders and obligate resprouters, and facultative species. We recorded all woody species and geographical features on 94 (75 m) plots of cork oak woodlands in the southern Iberian Peninsula. For each regenerative type (resprouters, seeders and species with both traits-facultative species), we tested the relationship between the number of species and the predictors using a generalised linear mixed model. The fixed predictor considered at the large scale was altitude, and fixed predictors considered at the local scale were aspect (north/south) and disturbance (fire and clearing by heavy machinery; yes/no). The random predictor was the factor of site. When this factor did not have significant effect for some regenerative types, these relationships was tested using a generalised linear model. Resprouting species were most represented at lower altitudes and in undisturbed sites, while seeders were also at lower altitudes but mostly on south-facing slopes, especially south-facing disturbed sites. For facultative species, site is the most important variable. The proportion of seeders from the total species is not related to altitude, but it is related to disturbance and aspect. These results suggest that there is no segregation of the richness of seeders and resprouters at the large scale (altitudinal gradient). Differences appeared at the local scale (aspect and disturbance). [ABSTRACT FROM AUTHOR]

Abstract: In this study we describe the biogeographic patterns of the endemic cacti from the Atacama Desert to the Mediterranean area of Chile. Our goals were: (1) to identify areas of high endemism, (2) to test Rapoport’s rule, (3) to test the geometric constraints hypothesis, (4) to explore temperature and precipitation as explanatory variables of species richness. We used a list of 72 species of cacti, ranging from 18° to 36° S and from 0 to 4500 m.a.s.l. A Bayesian analysis of Endemicity (BAE) was used to evaluate hierarchical relationships of endemism between different latitudinal bands. Rapoport’s rule was evaluated by examining the relationships between latitudinal/altitudinal mid-point, latitudinal/altitudinal range extent and species richness. The geometric constraints hypothesis was tested by examining the existence of mid-domain effect. The BAE indicated two areas of endemism: (1) the northern area between 18° S and 26° S, and (2) the southern area between 27° S and 36° S. The shape of the latitudinal gradient is non-linear, supporting the geometric constraints hypothesis. Altitudinal patterns, however, support Rapoport’s rule; a peak of endemism was found at low altitudes. The explanatory variables were elevation, minimum temperature of the coldest month, mean temperature of wettest quarter and annual precipitation. [Copyright &y& Elsevier]

Background: Due to its complex, dynamic and well-known paleogeography, the Mediterranean region provides an ideal framework to study the colonization history of plant lineages. The genus Linaria has its diversity centre in the Mediterranean region, both in Europe and Africa. The last land connection between both continental plates occurred during the Messinian Salinity Crisis, in the late Miocene (5.96 to 5.33 Ma). Methodology/Principal Findings: We analyzed the colonization history of Linaria sect. Versicolores (bifid toadflaxes), which includes c. 22 species distributed across the Mediterranean, including Europe and Africa. Two cpDNA regions (rpl32-trnLUAG and trnK-matK) were sequenced from 66 samples of Linaria. We conducted phylogenetic, dating, biogeographic and phylogeographic analyses to reconstruct colonization patterns in space and time. Four major clades were found: two of them exclusively contain Iberian samples, while the other two include northern African samples together with some European samples. The bifid toadflaxes have been split in African and European clades since the late Miocene, and most lineage and speciation differentiation occurred during the Pliocene and Quaternary. We have strongly inferred four events of post-Messinian colonization following long-distance dispersal from northern Africa to the Iberian Peninsula, Sicily and Greece. Conclusions/Significance: The current distribution of Linaria sect. Versicolores lineages is explained by both ancient isolation between African and European populations and recent events of long-distance dispersal over sea barriers. This result provides new evidence for the biogeographic complexity of the Mediterranean region. [ABSTRACT FROM AUTHOR]

The composition and conservation of plant communities is greatly influenced by the soil seed bank. Information on the soil seed banks and the remaining vegetation in these ecosystems is crucial for guiding the restoration efforts. his study examines the size, species richness, diversity, uniformity, and similarity of soil seed banks and aboveground vegetation in 6 different grazing lands including coastal pasture, reseeded pasture, artificial pasture, lowland shrubland, ungrazed pasture, and hillside shrubland. Forty-eight soil samples were taken by cores with a diameter and depth of 10 cm from each of grazing lands in August of 2007. A vegetation survey was conducted using a 0.5 x 0.5-m quadrant in both the spring and fall. Eighty species were observed in soil seed banks and aboveground vegetation. The largest seed bank was observed in reseeded pasture (7,715 seed/m² ), while the smallest seed bank was found in coastal pasture (2,755 seed/m² ). Coastal pasture also possessed the least amount of aboveground vegetation (131 plants/m² ). he most aboveground vegetation was found in ungrazed pasture (155 plants/m² ). he most common species in seed banks were annual and perennial grasses in reseeded pasture, annual forbs in artificial pasture and hillside shrubland, and perennial forbs in low shrubland and ungrazed pasture. Species richness, diversity, and uniformity in seed banks were highest in lowland shrubland and lowest in artificial pasture. The seed bank and aboveground vegetation were similar in ungrazed pasture, coastal pasture, reseeded pasture, low shrubland, hillside shrubland and artificial pasture. Shrublands play an important role in species richness and the number of germinated seeds from seed banks of grazing lands in southern Marmara. he results showed that reseeding or a decrease in grazing pressure may improve the condition of grazing lands. [ABSTRACT FROM AUTHOR]

Abstract: Modelling ozone (O3) deposition for impact risk assessment is still poorly developed for herbaceous vegetation, particularly for Mediterranean annual pastures. High inter-annual climatic variability in the Mediterranean area makes it difficult to develop models characterizing gas exchange behaviour and air pollutant absorption suitable for risk assessment. This paper presents a new model to estimate stomatal conductance (gs) of Trifolium subterraneum, a characteristic species of dehesa pastures. The MEDPAS (MEDiterranean PAStures) model couples 3 modules estimating soil water content (SWC), vegetation growth and g s. The g s module is a reparameterized version of the stomatal component of the EMEP DO3SE O3 deposition model. The MEDPAS model was applied to two contrasting years representing typical dry and humid springs respectively and with different O3 exposures. The MEDPAS model reproduced realistically the g s seasonal and inter-annual variations observed in the field. SWC was identified as the major driver of differences across years. Despite the higher O3 exposure in the dry year, meteorological conditions favoured 2.1 times higher g s and 56 day longer growing season in the humid year compared to the dry year. This resulted in higher ozone fluxes absorbed by T. subterraneum in the humid year. High inter-family variability was found in gas exchange rates, therefore limiting the relevance of single species O3 deposition flux modelling for dehesa pastures. Stomatal conductance dynamics at the canopy level need to be considered for more accurate O3 flux modelling for present and future climate scenarios in the Mediterranean area. [Copyright &y& Elsevier]

This study aimed to (i) investigate the congruence among the species composition and diversity of bryophytes and vascular plants in forests; (ii) test if site prioritization for conservation aims by the maximization of the pooled number of vascular plant species is effective to maximize the pooled number of bryophyte species. The study was performed in six forests in Tuscany, Italy. Four-hundred and twenty vascular plant species (61 of which were woody) and 128 bryophyte species were recorded in 109 plots. Despite the good predictive value of the compositional patterns of both woody plants and total vascular with respect to the compositional pattern of bryophytes, the species richness of the latter was only marginally related to the species richness of the former two. Bryophyte rare species were not spatially related to rare plant species and neither coincided with the sites of highest plant species richness. The species accumulation curves of bryophytes behaved differently with respect to those of woody plants or total vascular plants. Reserve selection analysis based on the maximization of the pooled species richness of either woody plants or total vascular plants were not effective in maximizing the pooled species richness of bryophytes. This study indicates that species diversity of vascular plants is not likely to be a good indicator of the bryophyte species diversity in Mediterranean forests. [ABSTRACT FROM AUTHOR]

We hypothesized that the spatial configuration and dynamics of periurban forest patches in Barcelona (NE of Spain) played a minor role in determining plant species richness and assemblage compared to site conditions, and particularly to both direct (measured at plot level) and potential (inferred from landscape metrics) human-associated site disturbance. The presence of all understory vascular plants was recorded on 252 plots of 100 m2 randomly selected within forest patches ranging in size from 0.25 ha to 218 ha. Species were divided into 6 groups, according to their ecology and conservation status. Site condition was assessed at plot level and included physical attributes, human-induced disturbance and Quercus spp. tree cover.Landscape structure and dynamics were assessed from patch metrics and patch history. We also calculated a set of landscape metrics related to potential human accessibility to forests. Results of multiple linear regressions indicated that the variance explained for non-forest species groups was higher than for forest species richness. Most of the main correlates corresponded to site disturbance variables related to direct human alteration, or to landscape variables associated to indirect human effects on forests: Quercus tree cover (a proxy for successional status) was the most important correlate of non-forest species richness, which decreased when Quercus tree cover increased. Human-induced disturbance was an important correlate of synanthropic and total species richness, which were higher in recently managed and in highly frequented forests. Potential human accessibility also affected the richness of most species groups. In contrast, patch size, patch shape and connectivity played a minor role, as did patch history. We conclude that human influence on species richness in periurban forests takes place on a small scale, whereas large-scale effects attributable to landscape structure and fragmentation are comparatively less important. Implicat [ABSTRACT FROM AUTHOR]

Authors briefly present some observations and reflections on the “seeding strategy” of some plant species ( Cistus spp., Cistaceae , in particular) in the Mediterranean area in relation to fire: they conclude it does not seem a specific adaptation to wildfires (as suggested in a relevant part of the recent literature), but a generalistic adaptation to open, high energy and variable habitats with aleatory fluctuations. The difference is important both for theoretical and applied aspects, e.g. for the correct management of Cistus species and of other Mediterranean species and habitats. [ABSTRACT FROM AUTHOR]

In mountainous regions, climate warming is expected to shift species' ranges to higher altitudes. Evidence for such shifts is still mostly from revisitations of historical sites. We present recent (2001 to 2008) changes in vascular plant species richness observed in a standardized monitoring network across Europe's major mountain ranges. Species have moved upslope on average. However, these shifts had opposite effects on the summit floras' species richness in boreal-temperate mountain regions (+3.9 species on average) and Mediterranean mountain regions (-1.4 species), probably because recent climatic trends have decreased the availability of water in the European south. Because Mediterranean mountains are particularly rich in endemic species, a continuation of these trends might shrink the European mountain flora, despite an average increase in summit species richness across the region. [ABSTRACT FROM AUTHOR]