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Understanding constraints to phenotypic plasticity is key given its role on the response of organisms to environmental change. It has been suggested that phenotypic integration, the structure of trait covariation, could limit trait plasticity. However, the relationship between plasticity and integration is far from resolved. Using a database of functional plasticity to drought of a Mediterranean shrub that included 20 ecophysiological traits, we assessed environmentally-induced changes in phenotypic integration and whether integration constrained the expression of plasticity, accounting for thewithin-environment phenotypic variation of traits. Furthermore, we provide the first test of the association between differential trait plasticity and trait integration across an optimumand a stressful environment. Phenotypic plasticity was positively associated with phenotypic integration in both environments, but this relationship was lost when phenotypic variation was considered. The similarityin the plastic response of two traits predicted their integration across environments, with integrated traits having more similar plasticity. Such variation in the plasticity of traits partly explained the lower phenotypic integration found in the stressful environment. We found no evidence that integration may constitute an internal constraint to plasticity. Rather, we present the first empirical demonstration that differences in plastic responses mayinvolve a major reorganization of the relationships among traits, and challenge the notion thatstress generally induces a tighter phenotype., This work was funded by grants GYPSEVOL (CGL2016-75566-P), Remedinal (TE-CM: S2018/EMT-4338), Phenotypes (PGC2018-099115-B-I00) and the Ramon y Cajal Programme of the Spanish Ministry of Economy and Competitiveness.

1. Plant species that grow across environmental gradients show a range of trait ex-pression, but traits do not vary independently. In fact, phenotypes are integrated expressions of multiple traits that covary due to trade-offs among functions and processes. Understanding trait covariation structures will ultimately help with predicting species' responses to change and developing management actions., 2. We measured variation and covariation (a proxy of phenotypic integration) among functional traits of Pinus sylvestris from paired populations across its European distribution. Populations within a pair were close enough to be in gene flow con-tact but located in contrasting environmental conditions across a local gradient. Measured traits represented three axes of variation (groups of traits) related to a tree's competitive ability and the trade-off between resource acquisition and conservation, namely plant size measures and stem and foliar traits., 3. Results revealed important intra- and inter-population trait variability. In particular, at the population level, trait means shifted across the climatic gradient mainly de-scribed by mean annual temperature. Moreover, we found a higher degree of trait covariation in populations under harsher environments (i.e. lower environmental suitability for the species). This pattern was consistent within population pairs, suggesting that higher trait covariation may be adaptive, being more coordinated in sites with harsher conditions. At larger spatial scales, we found a less conclusive pattern with a trend of increasing covariation at the northern edge of the species distribution. This result suggests that at larger scales different processes may be in-volved in the trade-off between the adaptive value of phenotypic covariation ver-sus its constraints on trait combinations that may limit plant's response capability., 4. Synthesis. Trait covariation varies at different spatial scales, increasing under harsher conditions, and the robustness and repeatability of this pattern suggests its adaptive role for the species' responses to different environments., Funding was provided by the European Union Horizon 2020 Project GenTree (Grant Agreement No. 676876). Extra support came from the Spanish projects REMEDINAL TE-CM (Autonomous Community of Madrid, S2018/EMT-4338), Phenotypes (PGC2018-099115-B-100), COMEDIAS (CGL2017-83170-R, Spanish Ministry of Science, Innovation and Universities), and Swiss Secretariat for Education, Research and Innovation (SERI) under contract No. 6.0032. R.B. is now funded by the Contrato-Programa CEEC Individual, Fundação para a Ciência e Tecnologia, Portugal. B.C. was funded by CAPES fellowship (DOC-PLENO -Programa de Doutorado Pleno no Exterior. Grant Agreement No. 99999.001266/2015-02, Brazil). C.C.B. was supported by a post-doctoral fellowship of the Ramón Areces Foundation.

© 2015 Geobotanisches Institut ETH, Stiftung Ruebel. Climate change is expected to alter the geographic distribution of many plant species worldwide. However, there is still no clear evidence showing a generalised direction and magnitude of these distribution shifts. Here, we have surveyed, in nine mountainous regions in Spain, an array of tree species along entire elevational ranges, as surrogates of their global climatic ranges, to test for elevational shifts towards cooler locations. We analysed the distribution recruitment patterns of five dominant tree species, recording the abundance and measuring the primary growth of juveniles in 306 plots. Three of the species have a temperate-boreal distribution with populations at their southern edge in the Mediterranean mountain ranges: Pinus sylvestris, Pinus uncinata and Fagus sylvatica; and the other two species have a Mediterranean distribution: Quercus ilex and Pinus nigra. Despite the contrasting phylogenies and biogeographies, we identified a similar pattern in recruitment abundance across species, with an asymmetric distribution of juveniles (more recruits in the middle-upper elevation of their range), but higher annual growths at lower elevations. This survival-growth trade-off at the early recruitment stage may potentially counterbalance at population level the negative effect of global warming on recruit survival at the lower edge of species ranges. These findings suggest a demographic stabilisation process at the early recruitment stage of these tree species, and highlight the importance of considering the different demographic stages across the whole climatic range to understand the effects that climate change may exert on species distributions and population dynamics., Funding also was provided by the Spanish Ministry for Innovation and Science with the grant Consolider-Montes (CSD2008 00040), VULGLO (CGL201022180 C03 03), MOUNTAINS (CGL-2012-38427), the Community of Madrid grant REMEDINAL 2 (CM S2009 AMB 1783) and the European Union with the projects BACCARA (CE: FP7-226299, 7FP) and FunDivEUROPE (CE: FP7-ENV-2010. 265171)., RB was funded by a MarieCurie IEF fellowship (FP7-PEOPLE-2011-IEF).

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Se trata de ofrecer una panorámica del impacto de las teorías feministas postmodernas sobre la producción artística. A partir de un profundo cuestionamiento de la validez de paradigma androcéntrico que permea la cultura occidental, no pocas mujeres artistas (Judy Chicago, Sophie Calle o Annette Messager) se proponen crear un nuevo lenguaje estético que dé testimonio de las experiencias femeninas. Además, de entre los diferentes discursos de ruptura con la discursividad masculina, centramos nuestro interés en la propuesta de Judith Butler en torno a la fuerza performativa de lo queer.

Rainfall and biocrusts are important sources of temporal and spatial environmental heterogeneity and niche differentiation for annual plants, a major component of diversity in drylands. Therefore, global change processes comprising shifts in rainfall timing and drought exacerbation, together with biocrust disturbance may affect species coexistence and result in disrupted diversity patterns. In this study, we experimentally evaluated the effects of the rainfall amount and timing as well as physical biocrust disturbance and their interaction on the taxonomic, phylogenetic and functional diversity of annual plant communities on gypsum soil drylands. All diversity estimates were determined at different times during community development in each experimental unit (α), as the contribution of each experimental unit to the total diversity in each treatment (β) and as the total diversity in each treatment (γ). Rainfall timings led to changes in all diversity dimensions, with higher diversity under the typical timing. The community was quite resilient to moderate reductions in rainfall, but extreme droughts decreased the alpha and beta taxonomic, functional and phylogenetic diversities. In addition, the simultaneous occurrence of biocrust disturbance and extreme drought led to consistent collapses in all diversity dimensions, probably because the effects of water shortage were exacerbated. Observations of the community at different times during its development highlighted the importance of regenerative strategies for niche differentiation and species coexistence, and their strong dependence on global change drivers. Indeed, our experimental study demonstrated that rainfall patterns and biocrusts are key factors related to the maintenance of diversity in semiarid annual plant communities. In particular, our results highlight the key role of biocrusts in modulating the effects of drought on plant diversity and the need for integrative approaches that consider both plants and biocrusts in order to elucidate the influence of climate change on the diversity of drylands. Comunidad de Madrid (GrantNumber(s): Remedinal TE-CM: S2018/EMT-4338) Ministerio de Economía y Competitividad (GrantNumber(s): Agora-CGL2016-77417) Universidad Rey Juan Carlos (GrantNumber(s): GYPVIFUN-M2148) European Horizon 2020 Programme (GrantNumber(s): Gypworld H2020-MSCA-RISE-2007-777803)

Understanding how functional and phylogenetic patterns vary among scales and along ecological gradients within a given species pool is critical for inferring community assembly processes. However, we lack a clear understanding of these patterns in stressful habitats such as Mediterranean high mountains where ongoing global warming is expected to affect species fitness and species interactions, and subsequently species turnover. In this study, we investigated 39 grasslands with the same type of plant community and very little species turnover across an elevation gradient above the treeline at Sierra de Guadarrama National Park in central Spain. In particular, we assessed functional and phylogenetic patterns, including functional heterogeneity, using a multi-scale approach (cells, subplots, and plots) and determined the relevance of key ecological factors (i.e., elevation, potential solar radiation, pH, soil organic carbon, species richness, and functional heterogeneity) that affect functional and phylogenetic patterns at each spatial scale. Overall, at the plot scale, coexisting species tended to be more functionally and phylogenetically similar. By contrast, at the subplot and cell scales, species tended to be more functionally different but phylogenetically similar. Functional heterogeneity at the cell scale was comparable to the variation across plots along the gradient. The relevance of ecological factors that regulate diversity patterns varied among spatial scales. An increase in elevation resulted in functional clustering at larger scales and phylogenetic overdispersion at a smaller scale. The soil pH and organic carbon levels exhibited complex functional patterns, especially at small spatial scales, where an increase in pH led to clustering patterns for the traits related to the leaf economic spectrum (i.e., foliar thickness, specific leaf area, and leaf dry matter content). Our findings confirm the presence of primary environmental filters (coldness and summer drought at our study sites) that constrain the regional species pool, suggesting the presence of additional assembly mechanisms that act at the smallest scale (e.g., micro-environmental gradients and/or species interactions). Functional and phylogenetic relatedness should be determined using a multi-scale approach to help interpret community assembly processes and understand the initial community responses to environmental changes, including ongoing global warming., This research was supported by the Spanish Ministry of Economy and Competitiveness (PHENOTYPES project, PGC2018-099115-B-100), Community of Madrid (REMEDINAL TE-CM project, S2018/EMT-4338), and Grant Agency of the Czech Republic (P505/12/1296).

espanolEl objetivo de la presente investigacion trata de caracterizar las diferencias que se dan en indicadores de rendimiento de los Grand Slams de tenis, con el fin de identificar aquellas conductas tecnicas y tacticas que resulten mas eficaces en situaciones reales de juego. Se trata de un estudio descriptivo y observacional, de metodologia cuantitativa. La muestra estuvo compuesta por 338 partidos, de la categoria individual absoluta masculina en la temporada 2018 de tres torneos Grand Slam (Roland Garros, Wimbledon y Open EEUU). Para ello, se analizaron las diferencias de en los indicadores de rendimiento en diversas variables situacionales (tipo de torneo, resultado del partido, match status y diferencia entre sets) a traves de analisis descriptivos e inferenciales. Los resultados mostraron que existen indicadores de rendimiento y diferencias significativas en los torneos analizados en cuanto al tipo de torneo, resultado del partido, match status y en menor medida en la diferencia entre sets. Concluyendo que los indicadores de rendimiento son propios de cada torneo o superficie de juego, que la importancia de llevar la iniciativa es fundamental para ganar en tenis y que la forma de juego no varia segun va transcurriendo el partido. Estos hallazgos resultan de gran interes, pues condicionan su puesta a punto para cada torneo y el juego de los tenistas, estableciendose diferentes estrategias de competicion. EnglishThe objective of this research is to characterize the differences in performance indicators of Grand Slam tennis, in order to identify those technical and tactical behaviors that are more effective in real life playing situations. It is a descriptive and observational study, with a quantitative methodology. The sample was composed of 338 matches, of the absolute individual male category in the 2018 season of three Grand Slam tournaments (Roland Garros, Wimbledon and US Open). The differences in performance indicators in various situational variables (type of tournament, match result, match status and difference between sets) were analyzed through descriptive and inferential analysis. The results showed that there are significant performance indicators and differences in the analyzed tournaments in terms of tournament type, match result, match status and to a lesser extent in the difference between sets. We concluded that performance indicators are specific to each tournament or playing surface, that the importance of taking the initiative is fundamental to winning in tennis and that the form of play does not vary as the match progresses. These findings are of great interest, as they condition their setting for each tournament and the play of the players, establishing different competition strategies.

Population persistence is strongly determined by climatic variability. Changes in the patterns of climatic events linked to global warming may alter population dynamics, but their effects may be strongly modulated by biotic interactions. Plant populations interact with each other in such a way that responses to climate of a single population may impact the dynamics of the whole community. In this study, we assess how climate variability affects persistence and coexistence of two dominant plant species in a semiarid shrub community on gypsum soils. We use 9 years of demographic data to parameterize demographic models and to simulate population dynamics under different climatic and ecological scenarios. We observe that populations of both coexisting species may respond to common climatic fluctuations both similarly and in idiosyncratic ways, depending on the yearly combination of climatic factors. Biotic interactions (both within and among species) modulate some of their vital rates, but their effects on population dynamics highly depend on climatic fluctuations. Our results indicate that increased levels of climatic variability may alter interspecific relationships. These alterations might potentially affect species coexistence, disrupting competitive hierarchies and ultimately leading to abrupt changes in community composition.

The effects of habitat fragmentation on plant populations are complex, as it might disrupt many ecological processes, including plant reproduction and plant-animal interactions. Gypsum specialist plants may be resilient to fragmentation due to their evolutionary history in fragmented landscapes, but the effects on non-specialist plants occurring in gypsum are unknown. We conducted a study focusing on different aspects of the reproductive cycle of Astragalus incanus subsp. incanus, a plant facultatively linked to gypsum soils. We focused on plant fecundity and pre-dispersal predation, obtained from field observations, and offspring performance, assessed in a common garden. Beyond fragment size and connectivity, we also considered habitat quality, population size and density and plant size as predictors. Fragment size and connectivity had no effect on plant fecundity, but jointly determined fruit predation, while fragment size was positively related to offspring growth. Population density, rather than population size, had a positive effect on predation but negatively affected plant fecundity and offspring performance. Habitat quality reduced both plant fecundity and predation incidence. In this non-specialist species, habitat fragmentation, population features and habitat quality affect different facets of plant performance. Predation was the only process clearly affected by fragmentation variables, fecundity mainly depended on population features and offspring performance and was better explained by mother plant identity. Our results show the need to consider habitat and population features together with fragment size and connectivity in order to assess the effects of fragmentation. Importantly, these effects can involve different aspects of plant reproduction, including plant-animal interactions.

Previous studies found that plant communities on infertile soils are relatively resistant to climatic variation due to stress tolerance adaptations. However, the species assemblies in gypsum soil habitats require further investigation. Thus, we considered the following questions. (1) Do harsher arid conditions determine the characteristics of the species that form plant assemblages? (2) Is the selection of the species that assemble in arid conditions mediated by their ability to grow on gypsum soils? (3) Is the selection of species that assemble in harsher conditions related to phylogenetically conserved functional traits? Perennial plant communities were analysed in 89 gypsum-soil sites along a 400 km climate gradient from the central to southeastern Iberian Peninsula. Each local assemblage was analysed in 30 × 30 m plots and described based on taxonomic, functional (soil plant affinity) and phylogenetic parameters. The mean maximum temperatures in the hottest month, mean annual precipitation and their interaction terms were used as surrogates for the aridity conditions in generalized linear models. In the hottest locations, the gypsophily range narrowed and the mean gypsophily increased at the community level, thereby suggesting the filtering of species and the dominance of soil specialists in the actual plant assemblies. Drier sites had higher taxonomic diversity. The species that formed the perennial communities were close in evolutionary terms at the two ends of the aridity gradient. The mean maximum temperatures in the hottest month had the main abiotic filtering effect on perennial plant communities, which was mediated by the ability of species to grow on gypsum soils, and thus gypsum specialists dominated the species assemblies in the hottest locations. In contrast, the perennial communities on gypsum soils were relatively resistant to changes in precipitation. Our findings suggest that the warmer environmental conditions predicted by global change models will favour gypsum specialists over generalists., We found that the perennial communities on gypsum soils were relatively resistant to changes in precipitation; however, temperatures in the hottest month were the main factor responsible for the selection of the species that finally established to form communities. It should be noted that species adapted to grow on gypsum soils (i.e. gypsophites) dominated plant communities in the hottest locations. Our findings suggest that the warmer environmental conditions predicted by global change models will favour gypsum specialists over generalists.

Studies that analyze the actions carried out by paddle tennis players during the point are scarce. The present investigation characterizes every action in which a stroke by a pair in a defensive position sends the ball over the position of a pair in an offensive position. It is a descriptive and observational study of quantitative methodology. The sample consisted of 1324 actions, statistical analysis units, from the women's circuit in the 2018 World Padel Tour (WPT) season. For this study, various situational, dependent, and independent variables were analyzed. The results showed the number of times the categories of each variable occurred, as well as the significant relationships between the independent variable kind of hit and the dependent variables &ldquo, actions that facilitate the possible change of position&rdquo, (AFPCP) and &ldquo, incidences in the game&rdquo, (IG). The conclusion is that the lob is the most effective kind of hit (CSR = 4.9) to achieve the offensive position (CSR = 11.4), even if the point does not finish (CSR = 5.8), leading to more position exchanges during the same point in the AFPCP. These findings are of great interest since they give information about how and why certain behaviors produce a certain result.

Functional traits have emerged as a key to understand species responses to environmental conditions. The concerted expression of multiple traits gives rise to the phenotype of each individual, which is the one interacting with the environment and evolving. However, patterns of trait covariation and how they vary in response to environmental conditions remain poorly understood, particularly at the intraspecific scale. Here, we have measured traits at different scales and in different organs, and analysed their covariation in a large number of conspecifics distributed in two contrasting environments. We expected significant correlations among traits, not only within clusters of traits as found in global, multispecies studies, but also among clusters, with more relationships within clusters, due to genetic constraints, and among clusters due to more coordinated phenotypes than community level, multispecies studies. We surveyed 100 Pinus sylvestris trees in a Mediterranean mountainous area distributed in two contrasting elevations. We measured 13 functional traits, in three clusters (leaf, stem and whole-plant traits), and analysed their variation and coordination. We found significant coordination among traits belonging to different clusters that reveals coordinated phenotypes. However, we found fewer correlations within trait clusters than initially expected. Trait correlation structures (number, intensity and type of correlations among traits) differed among individuals at different elevations. We observed more correlations within trait clusters at low elevation compared to those at high elevation. Moreover, the higher number of correlations among different trait clusters and the lower trait variation at the higher elevation suggests that variability decreases under more stressful conditions. Altogether, our results reveal that traits at intraspecific scale are coordinated in a broad network and not only within clusters of traits but also that this trait covariation is significantly affected by environmental conditions., BC thanks for a research scholarship from Coordenacão de Aperfeicçoamento de Pessoal de Nıvel Superior- CAPES [DOC-PLENO-Programade Doutorado Plenono Exterior. Grant Agreement No 99999.001266/2015-02]. All authors acknowledge support from the European Union Horizon 2020 Research and Innovation Programme Project GenTree [Grant Agreement No. 676876]; REMEDINALTC-CM [Autonomous Community of Madrid, S2018/EMT-4338]; COMEDIAS FEDER [CGL2017-83170-R, Spanish Ministry of Science, Innovation and Universities] and LINC Global [4540-143AP] projects.

According to the competitive exclusion principle, species with low competitive abilities should be excluded by more efficient competitors; yet, they generally remain as rare species. Here, we describe the positive and negative spatial association networks of 326 disparate assemblages, showing a general organization pattern that simultaneously supports the primacy of competition and the persistence of rare species. Abundant species monopolize negative associations in about 90% of the assemblages. On the other hand, rare species are mostly involved in positive associations, forming small network modules. Simulations suggest that positive interactions among rare species and microhabitat preferences are the most probable mechanisms underpinning this pattern and rare species persistence. The consistent results across taxa and geography suggest a general explanation for the maintenance of biodiversity in competitive environments., J.C. is supported by the Carl Tryggers Foundation for Scientific Research (no. CTS 16:384). E.A. is supported by a postdoctoral grant (no. CT39/17) funded by the Universidad Complutense de Madrid. C.J.M. is supported by the Swiss National Science Foundation (grant no. SNSF-31003A-144162). R.B.-M. is supported by the Spanish Ministry of Science and Innovation predoctoral fellowship no. BES-2013-065753. M.S., J.A.B.-C. and J.M.-G. acknowledge support from the University of Geneva (project: C-CIA; no. 309354). X.A. is supported by a Ramón y Cajal research contract by the Spanish Ministry of Economy and Competitiveness (MINECO, no. RYC-2015-18448). M.R. is supported by the Swedish Research Council grant no. 2016-00796. J.A.N. was supported by a Colombian COLCIENCIAS doctoral scholarship (no. 617-2013). F.A.-M. is grateful to CAPES for a doctoral scholarship (no. 120147/2016-01). A.L., P.F. and J.M.-G. were funded by the AGORA Project (MINECO, no. CGL2016-77417-P). C.M.-M. was supported by an IdEx Bordeaux Postdoctoral Fellowship (VECLIMED project). A.H. was supported by the University of Alcalá own research programme 2018 postdoctoral grant and Basque Country Government funding support to FisioClimaCO2 (IT1022-16) research group. L.J. received productivity grants from of CNPq (process no. 307597/2016-4).

More tree species can increase the carbon storage capacity of forests (here referred to as the more species hypothesis) through increased tree productivity and tree abundance resulting from complementarity, but they can also be the consequence of increased tree abundance through increased available energy (more individuals hypothesis). To test these two contrasting hypotheses, we analyse the most plausible pathways in the richness-abundance relationship and its stability along global climatic gradients. We show that positive effect of species richness on tree abundance only prevails in eight of the twenty-three forest regions considered in this study. In the other forest regions, any benefit from having more species is just as likely (9 regions) or even less likely (6 regions) than the effects of having more individuals. We demonstrate that diversity effects prevail in the most productive environments, and abundance effects become dominant towards the most limiting conditions. These findings can contribute to refining cost-effective mitigation strategies based on fostering carbon storage through increased tree diversity. Specifically, in less productive environments, mitigation measures should promote abundance of locally adapted and stress tolerant tree species instead of increasing species richness., Correlations between tree species diversity and tree abundance are well established, but the direction of the relationship is unresolved. Here the authors use path models to estimate plausible causal pathways in the diversity-abundance relationship across 23 global forests regions, finding a lack of general support for a positive diversity-abundance relationship, which is prevalent in the most productive lands on Earth only

QUESTIONS: Positive and negative associations among species influence the structure of plant communities. Yet how these plant associations are assembled at the community level is poorly understood. We propose a new approach that combines spatial ecology, network theory and trait‐based ecology to examine the assembly of plant–plant associations at the community level. LOCATION: Gemmipass, Swiss Alps. METHODS: We fully mapped an alpine plant community at the individual plant level, recording both plant coordinates and functional traits for each individual. We identified non‐random species associations using spatial point‐pattern analysis and partialled out the effect of abiotic heterogeneity. We then analysed the plant network structure and used plant traits to predict species associations. RESULTS: We identified 36 significant spatial associations between plant species, 34 positive and two negatives. Dominant, stress‐tolerant species such as Dryas octopetala, Linaria alpina and Leontodon montanus were highly connected in the network, whereas rare, water‐ and nutrient‐demanding species such as Saxifraga aizoides, Galium anisophyllon and Thymus praecox were less connected compared to random expectation. The plant network was clustered, meaning that species were overall more connected among each other than expected by chance. CONCLUSIONS: Positive associations among species characterized the studied plant community. Besides the primary effect of associations of the “foundation” species D. octopetala with other species, these “subordinate” plants were also associated with each other. Our study reveals the assembly of plant communities as driven by positive associations among stress‐tolerant pioneer species, highlighting their role in supporting the cohesiveness of alpine plant communities.

We employed an individual-species approach based on the plant’s eye perspective to disentangle the effects of individual species on community assembly in a dry tropical forest of southern Ecuador. We completely mapped a forest plot of 9 ha, and measured several functional traits (leaf area, specific leaf area, wood density, seed mass and maximum height) for tree and shrub species. To account for stochastic and habitat filtering effects, we fitted spatial point processes for the 23 more abundant species in the plot, which confirmed that all species responded to plot scale habitat filtering and 14 were dispersal-limited. We tested the hypothesis that facilitative interactions would be prevalent in this dry forest. For this, we compared the distribution of taxonomic (TD), functional (FD) and phylogenetic (PD) diversity in the neighborhood of the studied species with the diversity expected under a null model combining habitat filtering and stochastic assembly. We found that in the fine spatial scales where species interactions are expected to occur (i.e., neighborhoods of 1–20 m) eight species did not show any significant pattern for TD, FD or PD. Eleven species showed evidences of facilitation (i.e., accumulated more TD than expected) but in some cases the facilitated neighborhoods had more FD or PD than expected, suggesting the joint effect of facilitation and competition based on niche differences. One species showed less TD than expected, accompanied by lower FD and higher PD, suggesting competition based on fitness differences. Our study shows that in this dry tropical forest, where abiotic stress is prevalent, the assembly of diversity is controlled by environmental heterogeneity and both facilitative and competitive biotic processes, all of them acting simultaneously and at the same scale in the same neighborhoods.

Gypsum endemics occur in naturally-fragmented habitats, which may lead to genetic erosion and higher vulnerability to the genetic effects of anthropogenic fragmentation. Conversely, evolution in a fragmented landscape could increase their resilience to the effects of further fragmentation, but no evidence is available in either direction. In this study, we capitalize on previous results showing high genetic variation and a negative, yet small, effect of fragmentation on genetic variation on the gypsophile Lepidium subulatum, and jointly assess two other co-occurring dominant gypsophiles: Helianthemum squamatum and Centaurea hyssopifolia. We sampled individuals of the species in 20 populations varying in their fragment size and connectivity (≈400 plants/species; 1138 individuals total), and assessed genetic variation and population structure using species-specific microsatellite markers. Genetic variation was high in populations of the three study species, as shown by the high expected heterozygosity (0.454–0.735) and allelic richness (2.875–8.125). Population differentiation was in general low, but H. squamatum showed a stronger spatial structure than the other species. No effects of fragment size or connectivity were found for H. squamatum or C. hyssopifolia, i.e. differences among populations in genetic variation were not related to the size or connectivity of the sampled habitat remnants. These results contrast with the expectation that habitat specialists may be genetically impoverished. Furthermore, the correlation of key genetic diversity indices among species suggests that some fragments harbor more genetically-diverse populations than others, which provides insights for their conservation. We propose that these species may offset the genetic effects of human-mediated further habitat loss and increased isolation.

Vegetation above treeline constitutes one of the most vulnerable ecosystems to climate warming and other drivers of Global Change. Given the panorama of such an uncertain future facing these plant communities, it is critical to know how they respond to environmental changes and improve the knowledge on the potential impacts of climate change on their distribution. Recently, with the impressive development of trait-based approaches, relevant progress has been made to better understand the relationships between environmental conditions and plant communities. In this data paper, we describe data on abundances of 327 alpine plant species across 430 subplots of 2.4 m × 2.4 m in three mountain ranges (Sierra de Guadarrama and Pyrenees in Spain, and the Central Andes in Chile). We provide data on different environmental variables that represent variation in abiotic conditions and operate at different spatial scales (e.g., climatic, topographic and soil conditions). Data on six plant functional traits are also shown, which were measured on ten individuals of each species, following standard protocols. We provided the dataset as tables in the supplementary material. This information could be used to analyse the relationship between the alpine vegetation and changes in environmental conditions, and ultimately, to understand ecosystem functioning and guide conservation strategies of theses threatened and valuable ecosystems. Keywords: Alpine grassland, Cover, Dataset, Mediterranean and temperate mountains, Vegetation survey, Plant functional trait

The aim of this study was to disentangle the effects of landscape configuration (i.e., fragment area, connectivity, and proximity to a busy highway) on the assembly of annual plant communities at different spatial scales. Our main hypothesis was that larger and more connected fragments would have higher species densities per plot and this may result in differences in turnover and nestedness patterns at the fine spatial scales where plants interact. Specifically, since Mediterranean annuals are known to form strong competitive hierarchies, we expected to find a nested pattern of beta diversity due to sequential species loss. The study area was a fragmented gypsum habitat in central Spain with a semiarid climate where two fragmentation drivers coexist: agricultural practices and a roadway. Larger fragments had higher species densities per plot (20 × 20 m). Nevertheless, we detected no effect on the species assembly at fine spatial scales (30 × 30 cm). However, when the fragment connectivity was high the species that appeared in poor quadrats (30 × 30 cm) comprised a subset of the species in rich quadrats. These results agree well with the establishment of strong competitive hierarchies among annual species. The distance to the highway influenced the identity of the species established in the community (i.e., species composition) at fine spatial scales, but we detected no effect on species turnover, nestedness, or species densities. The main conclusion of our study is that the effects of habitat fragmentation extend beyond the landscape scale and they determine the spatial assembly at fine spatial scales.

Both no-tillage and non-inversion tillage systems have been proposed within the context of 'conservation agriculture' as alternatives to conventional tillage for weed management and soil conservation. However, little information is available regarding their influence on weed community diversity and crop yield in Mediterranean cereal steppelands. Type of tillage represents a crop abiotic factor that largely influences the environmental conditions at the field scale to which weed communities may respond. The present paper examines the effect of no-tillage, subsoil tillage and minimum tillage (the latter two being non-inversion systems), on arable weed community diversity and composition in a cereal-legume crop rotation over 9 years. Their effects on crop yield are also explored. Inter-annual environmental variability was found to be more important than the tillage system in determining weed species diversity and assembly. None of the studied tillage systems exerted consistent effects, neither on weed community diversity nor on crop yields. In addition, the effect of tillage system on weed community diversity was crop-type dependent. The main effects of tillage systems were related to the composition of weed communities. Less common species resulted particularly affected while core species were consistent across tillage systems.

Global change pressures are jeopardizing the functioning and structure of most tropical forests and clouding the future for their biodiversity and provided services. Although the impact of direct destruction through deforestation and fragmentation is currently in the research portfolio, overgrazing, which is more diffuse and generalized but chronic, especially in the seasonal dry forests, has been by far less addressed. Overgrazing can lead to a dramatic change in natural regeneration, often triggering the collapse of dominant species. The almost monospecific dry forests of Bursera graveolens, one of the most representative forest of the Tumbesian region, are on the verge of extinction due to both direct destruction and chronic overgrazing and regeneration collapse in forest remnants. Here, we evaluated the impact of a very simple measure, the installation of fences, on the regeneration of ecological processes affecting the dominant species. We mapped and measured all Bursera individuals with a height greater than or equal to 30 cm in six 1-ha plots, 3 within and 3 outside fenced areas. Using spatial point pattern analysis, we inferred the importance of demographic and ecological processes affecting adults and juveniles in fenced and unfenced areas. The spatial structure of adults was similar in fenced and unfenced areas, varying from random to aggregated patterns, showing that fences did not interfere with ecological processes affecting adult trees. On the contrary, we found 2765 juveniles in the three fenced plots but none in free ranging areas. Juveniles showed heterogeneous clustered patterns, and their distribution and growth were negatively influenced both by the presence and the height of adult trees. On average, there was an exclusion zone of 10 m around adult trees were recruitment of juveniles was limited. Competition among juveniles appeared to be negligible. All in all, these results suggest that, in addition to recruitment, two of the main mechanisms that rule tree population dynamics in tropical forests, i.e., dispersal limitation and a Janzen-Connell-like mechanism favoring recruiting far from adult trees have been immediately restored in the fenced area. This shows that fencing is a viable tool for a fast regeneration and conservation of Bursera forests.

Background and aims In Mediterranean annual plants, germination mainly occurs during the autumn and only those seedlings that survive winter freezing can flower and produce seedlings in spring. Surprisingly, the effect of freezing events as an abiotic determinant of these communities remains unexplored. The present study aimed to investigate how freezing events affect annual Mediterranean communities and whether their functional structure as related to freezing resistance is linked to the main biotic and abiotic determinants of these communities. Methods In 120 plots located on a semi-arid Mediterranean steppe (Spain), the community functional structure related to the lethal temperature causing 50 % frost damage (LT50 trait) in seedlings was estimated and summarized as the community-weighted mean (CWM-LT50) and its functional diversity (FD-LT50). Plots were stratified according to distance to rabbit shelters and latrines as a proxy for rabbit density, proximity to Stipa tenacissima and spring water availability, where annual species abundance was recorded in all plots over three consecutive years. Key results Annual species were able to resist a threshold temperature of -4 °C and most had LT50 values around the absolute minimum temperature (-9.5 °C) in the three years. Higher rabbit densities led to lower CWM-LT50 and higher FD-LT50 values. Plots close to Stipa tussocks had higher CWM-LT50 values whereas water availability had no effects. Conclusions High freezing resistance was extended among winter annual species, suggesting the presence of an association between historical environmental filtering and low winter temperatures. However, the community functional structure related to freezing resistance remained variable among scenarios with differences in herbivory pressure and distance to perennial vegetation. The trends observed indicate that traits that allow plants to deal with herbivory may also promote freezing resistance, and that tussocks can act as nurses via microclimatic amelioration of harsher winter conditions.

The variability in space and time of a given set of traits can describe the biological activity of plants and influence species interactions and the properties of communities and ecosystems. However, seasonal variance in foliar traits of tree species has been poorly addressed in the Mediterranean climate despite its potential implications in fundamental processes such as light interception strategies. Due to seasonal variation in the apparent sun path’s trajectory, predictable radiation patterns across crown positions may determine the variance partitioning for light-related leaf traits in evergreens. We hypothesize that in the most exposed part of the crown i.e. south, trait variance should be constraint due to abiotic stress compared to less exposed crown positions. We partitioned the variance across five nested scales for a set of traits that capture leaf form, structure, position relative to the sun and the potential area exposed in a given time in Olea europaea L. trees. The scales included temporal variation due to sampling in two different seasons and twelve spatially structured crown positions within trees. We conducted multivariate analyses to assess the variability among traits, within trees and among trees The variance partitioning at the season scale was low and the structure conserved between seasons for most traits. Intraindividual variance was conspicuous for all traits evidencing a spatial gradient of trait distribution within trees from outer to inner layers and among paired crown sectors (North-East, South-West). Leaf angles and potential exposure to direct light had an absence of variance at scales above crown positions. The spatial distribution of crown sectors and layers had a distinct influence on the expression of leaf attributes among traits. Environmental filters may constrain variability on the outermost layer of the crown and on all crown positions during summer and winter, due to combination of the high irradiance and water stress in Mediterranean climates.

O presente trabalho analisa a assimilação produtiva heideggeriana da retórica aristotélica que encontramos em suas lições de 1924, Conceitos fundamentais da filosofia aristotélica, e sua posterior repercussão nas análises do impessoal cotidiano e do falatório em Ser e tempo. Primeiro se apresentam as linhas básicas da interpretação do jovem Heidegger dos escritos práticos e políticos de Aristóteles (1). Em seguida se perfila com mais detalhe sua releitura com explicação ontológica da Retórica de Aristóteles, com especial atenção para o plano da comunicabilidade das opiniões (2). E, finalmente, se mostram os aspectos positivos e negativos contidos no fenômeno do falatório analisado em Ser e tempo, um fenômeno que condensa boa parte das interpretações da retórica aristotélica (3).

Questions: How do roadsides interact with patches of natural vegetation in shaping perennial plant communities in fragmented agricultural areas? Are the observed differences due to the type of roadside (i.e. roadcuts, embankments or road verges) or are there other factors driving community structure and composition? Location: Stretch of motorway A3 and its surrounding area, central Spain. Methods: We analysed the variation in perennial plant species composition and diversity among 92 plots (400 m2 ). The plots were located in five different environmental scenarios, three of them in a fragmented landscape (patches of natural vegetation, embankments and roadcuts) and two in an unfragmented landscape (natural vegetation and road verges). In each plot, the cover of each perennial plant species and eight soil variables were assessed. We used phi coefficient of correlation to determine the scenario preferences of each species, Kruskal–Wallis tests to compare the soil variables between landscape scenarios and eight descriptive variables of the community, and RDA and partial RDA to evaluate the relative importance of the type of environmental scenario on the floristic community. Results: We identified 130 species, with only 16 species never appearing on roadsides. Perennial total cover, species richness, inverse Simpson’s index and number of protected species showed no significant differences between the five scenarios considered. In contrast, the number of nutrient-demanding species and restricted-range diversity had lower values in natural vegetation plots. Soil variables and the type of scenario together explained 28.5% of the species composition variation. Of this percentage, 6.8% was explained by soil variables, 12.1% by the type of scenario and 10.0% of the variation was shared between the two data sets. Conclusions: Our results show that almost all perennial species occurring in natural vegetation patches were also able to reach and settle in roadsides. However, soil conditions and other specific roadside variables generate different plant communities. In spite of the differences found between the perennial plant community of roadsides and their surrounding area, roadsides are excellent reservoirs of biodiversity.

Habitat fragmentation is a major driver of global change that has operated historically on Mediterranean ecosystems. However, more needs to be understood about how fragmentation influences ecological interactions, particularly pollination. Gypsum outcrops are historically fragmented Mediterranean habitats and settings for the evolution of many endangered soil-specialist plants with narrow ranges. In this study, we aimed to determine how fragmentation (area and connectivity) affects: (i) pollinator community composition and (ii) structural properties of pollination networks; and whether there are differences in the effects of fragmentation on: (iii) the number of interactions and visits among pollinator functional groups; and (iv) the number of interactions and specialisation degree between soil-specialist and soil-generalist plants. We characterised the degree of fragmentation and the pollination network structures in 12 gypsum habitat fragments embedded in a cropland matrix during two consecutive years. We found significant relationships between fragmentation and network structure. The effects of fragmentation differed among pollinator functional groups, but not between soil-specialist and soil-generalist plants, in terms of number of interactions. However, the relatively higher pollinator specialisation of soil-specialist plants suggested greater dependence on pollinators. Inter-annual variations in the network structures demonstrated the importance of temporal replication. The observed patterns related to the landscape structure and pollination at both the network and species levels provide insights into the key ecological processes in gypsum islands. These findings may help to identify the potential drivers of species persistence, especially for endangered soil-specialist plants with narrow ranges in a changing scenario with exacerbated habitat fragmentation.

Light-related leaf traits variation is structured among individuals and within individuals in a latitudinal pattern from the equator (high variation) toward the poles (lower variation). Intraspecific variation in leaf functional traits can play a crucial role at multiple ecological scales. However, our understanding of leaf functional trait variation (FV) across spatial scales is limited. Moreover, the influence of FV in specific responses to the environment remains poorly assessed. We investigated FV across multiple nested ecological scales in a set of leaf traits related to light interception and photosynthetic performance in eight populations of Olea europaea trees distributed over a wide latitudinal gradient (~60°). Specifically, we measured SLA, leaf shape, leaf’s spatial position (leaf angles) and leaf’s potential exposure to direct sunlight (silhouette area of the leaf blade and silhouette to area ratio of the leaf blade). The variability in leaf traits revealed two main patterns depending on the considered trait. Differences among sites absorbed >50% of the trait variation related to leaf shape and structure. Conversely, traits related to leaf position and exposure to direct light varied mostly within individuals among crown positions. The variation within trees for multiple traits ranged from 4 to 14%. Trees of equatorial populations had wider, thinner and more exposed leaves to direct light than trees of the remaining populations. The FV for multiple leaf traits at the tree scale was spatially structured within the tree crown and was higher for populations at the equator than for populations located in other latitudes. The differences among traits and scales in the magnitude of FV revealed a complex structure that could be linked to local adaptation.

Background and aims Local adaptation and phenotypic plasticity are considered key mechanisms for coping with climate warming, especially for plant species that inhabit island-like habitats. In Spain a complete guild of edaphic specialists, most of them threatened, occurs in gypsum outcrops, but how these species will respond to climate change has received little attention. Methods A reciprocal sowing experiment was performed to determine the extent of local adaptation and phenotypic plasticity in five gypsophytes with contrasting distributions along a climate gradient. Germination, seedling growth and survival were recorded during a 4-year period. Key results Plants responded plastically according to their positions along the regional climate gradient, as well as locally between matched locations. All species exhibited highly plastic responses and stress-tolerant behaviours, especially in terms of seedling survival during summer drought. However, no evidence of local adaptation was detected in any of the locations, where local individuals never performed better than those from other sites. In some sites, both germination and seedling recruitment were higher irrespective of parent plant origin. Conclusions The lack of local adaptation to drought displayed at the regeneration stage indicates limited capacity for in situ genetic response to new climate scenarios. Nevertheless, a plastic response along the climatic gradient does suggest a wider species-level capacity to enable these edaphic specialists to cope with increasing aridity over coming decades.

Many studies have shown evidence of very rapid natural colonization of trees on roadslopes. Tree colonization on roadslopes can be a usefultool in the ecological restoration ofthese degraded areas. However, little is known about the characteristics of the tree species capable of colonizing these novel habitats. Moreover, it is necessary to know how tree species respond to the two main limitations in these areas: microsite availability (i.e., roadslope characteristics) and seed arrival, which is related to propagule source, dispersion vector and landscape characteristics. The present study aims to investigate the natural colonization of tree species on roadslopes, as well as the factors determining their occurrence. We identified all tree individuals on 150 roadslopes, along 51 km of a motorway. A total of 1143 individuals belonging to 18 species was recorded. Most individuals found resulted from a natural colonization process, although we found various fruit trees (present in 7 roadslopes) and Robinia pseudoacacia (2 roadslopes), which are probably associated with unintentional human-mediated seed dispersal. Only the six most abundant species were analysed in detail: Populus nigra, Quercus ilex, Quercus pyrenaica, Fraxinus angustifolia, Salix spp. and Ulmus pumila. Each roadslope was characterized both by site variables and by surrounding variables. We analysed the effect of the descriptive variables on the occurrence and density of each species on the roadslopes, and we subsequently used decision trees (classification and regression trees) to analyse the combined effect of the different predictors considered. Our results show successful tree colonization on the roadslopes, although they appear to indicate limitations to colonization associated with the availability of propagules. Furthermore, tree species dispersed by animals required a continuous flow of seeds favoured by an appropriate community of seed dispersers and a suitable landscape structure. By contrast, wind-dispersed tree species basically need favourable site characteristics on the roadslopes.

Light is considered a non-limiting factor for vascular epiphytes. Nevertheless, an epiphyte's access to light may be limited by phorophyte shading and the spatio-temporal environmental patchiness characteristic of epiphytic habitats. We assessed the extent to which potential light interception in Rodriguezia granadensis, an epiphytic orchid, is determined by individual factors (plant size traits and leaf traits), or environmental heterogeneity (light patchiness) within the crown of the phorophyte, or both. We studied 104 adult plants growing on Psidium guajava trees in two habitats with contrasting canopy cover: a dry tropical forest edge, and isolated trees in a pasture. We recorded the number of leaves and the leaf area, the leaf position angles, and the potential exposure of the leaf surface to direct irradiance (silhouette area of the leaf blade), and the potential irradiance incident on each plant. We found the epiphytes experience a highly heterogeneous light environment in the crowns of P. guajava. Nonetheless, R. granadensis plants displayed a common light interception strategy typical of low-light environments, resembling terrestrial, forest understory plants. Potential exposure of the total leaf surface to direct irradiance correlated positively with plant size and within-plant variation in leaf orientation. In many-leaved individuals, within-plant variation in leaf angles produced complementary leaf positions that enhanced potential light interception. This light interception strategy suggests that, in contrast to current wisdom, enhancing light capture is important for vascular epiphytes in canopies with high spatio-temporal heterogeneity in light environments.

Understanding the factors limiting population growth is crucial for species management and conservation. We assessed the effects of seed and microsite limitation, along with climate variables, on Helianthemum squamatum, a gypsum soil specialist, in two sites in central Spain. We evaluated the effects of experimental seed addition and soil crust disturbance on H. squamatum vital rates (survival, growth and reproduction) across four years. We used this information to build integral projection models (IPMs) for each combination of management (seed addition or soil disturbance), site and year. We examined differences in population growth rate (λ) due to management using life table response experiments. Soil crust disturbance increased survival of mid to large size individuals and germination. Contributions to λ of positive individual growth (progression) and negative individual growth (retrogression) due to managements varied among years and sites. Soil crust disturbance increased λ in the site with the highest plant density, and seed addition had a moderate positive effect on λ in the site with lowest plant density. Population growth rate (λ) decreased by half in the driest year. Differences in management effects between sites may represent a shift from seed to microsite limitation at increasing densities. This shift underscores the importance of considering what factors limit population growth when selecting a management strategy.

Summary Most ecological theories that aim to explain coexistence in megadiverse communities employ a set of three rules to describe the stochastic geometry of biodiversity: (i) individuals exhibit intraspecific clustering; (ii) species abundances vary according to a log-normal distribution and (iii) the spatial arrangement between species is independent. The first two rules have received strong empirical support, but the third remains largely unexplored. To address this deficiency, we evaluated the independent species arrangement rule in a species-rich shrubland and its potential drivers, that is, the levels of species richness and intraspecific clustering exhibited by a given species at different scales, and the relative abundance of such species in the community. We found that interspecific associations were rare and that independence was positively related to species richness and intraspecific clustering, but negatively related to relative species abundances. Synthesis. Our results agree with the independent species arrangement rule and they provide empirical support for the stochastic geometry of biodiversity. In the context of species-rich plant communities, the likelihood of two species encountering is very small. However, our study demonstrated a novel feature of this context, where both intraspecific clustering (due limitations on dispersal) and relative species abundances play fundamental roles in determining the probability of two species encountering and interacting, especially at very fine spatial scales.

Understanding patterns of habitat natural recovery after human-made disturbances is critical for theconservation of ecosystems under high environmental stress, such as drylands. In particular, the unassisted estab-lishment of nonvascular plants such as biological soil crusts or biocrust communities (e.g., soil lichens, mossesand cyanobacteria) in newly formed habitats is not yet fully understood. However, the potential of biocrusts toimprove soil structure and function at the early stages of succession and promote ecosystem recovery is enor-mous. In this study, we evaluated the capacity of lichen biocrusts to spontaneously establish and develop on roadslopes in a Mediterranean shrubland. We also compared taxonomic and functional diversity of biocrusts betweenroad slopes and natural habitats in the surroundings. Biocrust richness and cover, species composition, and func-tional structure were measured in 17 road slopes (nine roadcuts and eight embankments) along a 13 km highwaystretch. Topography, soil properties and vascular plant communities of road slopes were also characterized. Weused Kruskal–Wallis tests and applied redundancy analysis (RDA) to test the effect of environmental scenario(road slopes vs. natural habitat) and other local factors on biocrust features. We found that biocrusts were com-mon in road slopes after∼20 years of construction with no human assistance needed. However, species richnessand cover were still lower than in natural remnants. Also, functional structure was quite similar between roadcuts(i.e., after soil excavation) and natural remnants, and topography and soil properties influenced species composi-tion while environmental scenario type and vascular plant cover did not. These findings further support the ideaof biocrusts as promising restoration tools in drylands and confirm the critical role of edaphic factors in biocrustestablishment and development in land-use change scenarios.

Disentangling the processes that drive plant community assembly is critical for understanding the patterns of plant diversity. We studied how different abiotic and biotic factors shape the interplay between the facets of alpine plant diversity, functional (FD), phylogenetic (PD) and taxonomic diversity (TD), in three different mountain ranges with contrasting evolutionary histories and climate conditions (Pyrenees and Mediterranean-type mountains in central Spain and Chilean Andes). We hypothesized that the causal links vary in strength and sign across regions. We used species inventories, functional trait data, and a phylogeny from 84 plant communities spread throughout three high-mountain alpine grasslands. Structural equation models were used to test our causal hypotheses on the relationships observed between the three diversity facets, and the abiotic (elevation, potential solar radiation and soil total nitrogen) and biotic factors (C-score). Despite our causal model presented a high variability in each mountain range, TD always decreased with increasing elevation (sum of direct and indirect effects). We also found some patterns suggesting that assembly processes could be climatically/biogeographically structured such as the negative relationship between FD and elevation found in Mediterranean mountains and the negative relationship between FD and TD found in both Spanish mountain ranges (independently of their different climates). A remarkable finding of this study is that ecological factors such as soil total nitrogen and elevation indirectly alter the relationships between the diversity facets. Our results suggest that diversity facets are simultaneously affected by different ecological and biogeographical/evolutionary processes, resulting in some general trends but also in parallel idiosyncratic patterns. Our findings highlight that although FD stand out by its explanatory power of community processes, TD and PD provide a complementary and necessary view that should not be disregarded in the attempt to globally explain community assembly processes.

Techniques for retrospective analysis of size dynamics at annual resolution remain poorly developed in lichens in general, and fruticose lichens in particular. Only a few attempts in very high latitudes suggested that growth might be studied as a chronosequence of inter-nodal branch elongations. Here we evaluated, for the first time, this hypothesis in a dry Mediterranean environment using the lichen Cladonia rangiformis as a case study. Mixed models supported a strong positive relationship between humidity measured as precipitation/PET and inter-nodal branch elongations. Importantly, model selection suggested that (i) the number of intermodal elongations were a major determinant of stem elongation, and (ii) a second-order temporal autocorrelation denoted legacies of environmental influences at least over the next 2 y. The strong growth–humidity relationship, along with the potential legacies observed, support the idea that inter-nodal branch elongations could be used to reconstruct growth chronologies at annual resolution in drylands. This finding highlights the high vulnerability of these organisms to rising aridity, and opens a new venue for climate reconstruction and other potential applications in Ecology and Earth Science disciplines.

(1) Background: Neotropical montane forests represent one of the most diverse world ecosystems, however, they are also among the most threatened ones mostly due to deforestation. Our main goal is to classify and clarify the forest types based on the changes in basal area (BA), tree density, and species composition of montane forests in Southern Ecuador, and to determine the influence of critical environmental and geomorphological factors. (2) Methods: One hundred thirty-two temporary plots of 400 m2 were installed in homogeneous and well-conserved forest stands. We identified and measured all trees &gt, 10 cm diameter breast height (DBH). We modeled species diversity (Fisher&rsquo, s alpha) change in relation to climatic, altitudinal, and geomorphological gradients using GLM and Kruskall-Wallis analyses. The change in composition was determined using cluster analyses (BIOENV analysis followed by a LINKTREE procedure). Non-metric multidimensional scaling (NMDS) was used to analyze changes across climatic and geomorphological gradients. Finally, we used a SIMPER analysis to identify the species that contributed most to the floristic dissimilarity among the identified altitudinal forests types. (3) Results: The floristic groups were determined by altitude, temperature, and isothermality, but also some geomorphological variables and lithology were used. Plots located in low hills have higher alpha diversity compared to the high hills and dissected mountains. (4) Conclusions: Altitude is the most important factor responsible for the division of structural and floristic groups. In addition, those plots located on the whitish tuff have higher alpha value diversity compared with plots in andesitic tuffs. Precipitation on the wettest quarter (&gt, 839 mm) and isothermality (&gt, 90.5) are the most relevant climatic factors driving the floristic classification.

High-mountain areas provide excellent opportunities to study the effects of combined abiotic stresses on plant physiology given their variety of steep ecological gradients, low anthropogenic disturbance and remarkable levels of taxonomic diversity. Efficient photoprotective and antioxidant scavenging mechanisms are vital for survival in high-mountain plants, having its altitudinal and seasonal variations determined by environmental or ontogenetic factors such as the decrease in mean temperatures and water availability. A number of stress indicators have been described in order to rapidly assess plant fitness in high-mountain environments. For instance, carbon isotope (δ13 C) and proline content as drought and temperature stress indicators, because of their link to water-use efficiency and osmotic adjustment; photosynthetic pigments, related to phenology, nutrient status, light and temperature stress; and non-structural carbohydrate accumulation in response to mild or brief drought conditions. The present review unveils the wide research opportunities available for the study of adaptive responses in high-mountain plants via stress indicators, and calls attention to the substantial knowledge gap existing between alpine zones and other mountainous regions, such as Mediterranean high-mountains. The aim is to grant a more holistic understanding of the physiological mechanisms driving plant life in high altitudes and improve the predictions of the effects of changing environments in these species and across ecological scales.

La idea de que la fenomenología de Husserl representa una suerte de filosofía reflexiva, basada en una metodología que desarrolla la tradición cartesiana, se ha convertido en una creencia ampliamente difundida en la literatura filosófica. Este énfasis puesto por Husserl en la reflexión fue arduamente criticado por Heidegger. Desde entonces resulta frecuente encontrarse con la afirmación de que Husserl y Heidegger desarrollan dos conceptos de fe-nomenología diferentes, incluso antagónicos. No se trata de seguir alimentando esta discusión historiográfica. Aquí, por una parte, se muestra el núcleo de la temprana crítica heideggeriana en el transcurso de sus primeras lecciones de Friburgo (1919-1923) y Marburgo (1924-1928) y, por otra, se sopesan algunas de las observaciones críticas de Heidegger a Husserl a la luz de evidencias textuales de la fenomenología husserliana, ignoradas no sólo por Heidegger, sino también por un sorprendente número de reconocidos especialistas en el campo de la filosofía, de las ciencias cognitivas y de la filosofía de la mente.The idea that Husserl’s phenomenology is a kind of reflective philosophy inspired by the Cartesian tradition has become a common-place in the philosophical literature. Heidegger was one of the first thinkers who criticized the Husserlian emphasis on reflection. Since then it is easy to find the affirmation that Husserl and Heidegger developed two different, even antagonistic concepts of phenomenology. Here is not the place to continue embracing this discussion. One the one hand, the present article shows Heidegger’s early criticism developed in the course of his first lectures in Freiburg (1919-1923) and Marburg (1924-1928). On the other hand, it weighs up some of Heidegger’s critical remarks regarding the reflective nature of Husserlian phenomenology in the light of important textual evidences ignored not only by Heidegger, but also by a surprising number of specialists in the fields of philosophy, cognitive sciences, and philosophy of mind.

BackgroundGypsum ecosystems are edaphic islands surrounded by a matrix that is inhospitable to gypsum soil plant specialists. These naturally fragmented landscapes are currently exacerbated due to man-made disturbances, jeopardising their valuable biodiversity. Concomitant action of other fragmentation drivers such as linear infrastructures may increase the already high threat to these specialists. Although some evidence suggest that gypsophytes are not evolutionary dead-ends and can respond to fragmentation by means of phenotypic plasticity, the simultaneous action of barriers to genetic flow can pose a severe hazard to their viability. Here, we evaluated the effect of a highway with heavy traffic on the genetic flow and diversity in the speciesLepidium subulatum, a dominant Iberian shrubby gypsophyte.MethodsWe tested the possible existence of bottlenecks, and estimated the genetic diversity, gene flow and genetic structure in the remnant populations, exploring in detail the effect of a highway as a possible barrier.ResultsResults showed variability in genetic diversity, migrants and structure. The highway had a low impact on the species since populations can retain high levels of genetic diversity and genetic parameter, likeFSTandFIS, did not seem to be affected. The presence of some level of genetic flow in both sides along the highway could explain the relatively high genetic diversity in the habitat remnants.DiscussionNatural fragmentation and their exacerbation by agriculture and linear infrastructures seem to be negligible for this species and do not limit its viability. The biological features, demographic dynamics and population structures of gypsum species seem to be a valuable, adaptive pre-requisite to be a soil specialist and to maintain its competitiveness with other species in such adverse stressful conditions.

Soil under nurse plants is more fertile than in the harsh surroundings. This is a primary mechanism involved in plant to plant facilitation and it is critical in structuring plant communities under stressful conditions. However we do not know how this soil enrichment process varies along complex environmental gradients and among coexisting nurse plants. Soil properties related to structure, resource stocks and microbial activity, were compared among up to ten nurse plant species and adjacent barren soil areas, along a 1600 m elevation gradient above the treeline in central Chilean Andes. Shifts in Relative Interaction Index (RII) sensu Armas (Ecology 85: 2682–2686, 2004) and in coefficient of variation on soil properties were also modelled. Soil under nurse plants was always richer than on barren areas irrespective of altitude, except in the case of texture with more small particles in the intermediate altitude. β-glucosidase activity was higher under cushion plants than under nurse plants with other growth habit. Besides β-glucosidase and phosphatase activities were more variable at higher altitudes. Nitrogen was more variable under nurse plants than in barren areas and its RII values were lower at intermediate altitudes. Soil amelioration by nurse plants occurred all along the studied environmental gradient promoting islands of fertility and a general increase on soil niches heterogeneity.

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.