Texto resumen.

Structural and nutrient traits of a leaf are important for understanding plant ecological strategies (e.g., drought avoidance). We studied the specific leaf area (SLA), leaf carbon content (LCC), leaf nitrogen content (LNC), leaf phosphorous content (LPC), and the phenophase sequence index (PSI) in 126 Mediterranean perennial species from predesert (SMS) and semiarid (SaMS) to subalpine (SAS), alpine cushion (AcS), and oro-Mediterranean (AjS) shrublands, which represent eight functional groups (evergreen and deciduous trees, evergreen large and half shrubs, deciduous large and half shrubs, succulents and perennial herbs). We analyzed the variation and relationships between leaf traits and PSI among shrublands, functional groups, and within species with drought-avoidance mechanisms. SLA variation of 20–60% could be ascribed to differences between functional groups and only 38–48% to different shrublands increasing from the predesert to the alpine. Alpine species display low PSI and N:P and high SLA, LNC, LPC, LCC, and C:N. On the contrary, predesert and semiarid showed high PSI and low SLA. SLA mediates the vegetative and reproductive phenological plant sequencing, high SLA is often associated with the overlapping in growth and reproductive phenophases with a seasonal reduction of vegetative growth, whereas low SLA is associated with vegetative and reproductive sequencing and a seasonal extension of vegetative growth. Species with drought-avoidance mechanisms (e.g., semideciduous species) contribute to an increase in the mean values of the SLA and LNC because these species show similar leaf and phenological patterns as the deciduous (high SLA and LNC and low PSI). The N:P indicates that only the alpine shrublands could present P limitations. The positive correlations between SLA and LPC and LNC and LPC (leaf economic spectrum) and the negative correlation between SLA and C:N were consistently maintained in the studied arid Mediterranean shrublands.

This work updates the existing list of obligate endemic serpentinophytes of the southern Iberian Peninsula. Serpentine ecosystems are developed on ultramafic outcrops which, although rare, have a worldwide distribution. The highly evolved and specialized flora that manages to inhabit these harsh ecosystems includes a very specialized and highly evolved group of plants known as serpentinophytes. Serpentinophytes are linked exclusively or almost exclusively to serpentine ecosystems. The existing list of obligate serpentinophytes (obligate endemics) which exist in the serpentine ecosystems of the southern Iberian Peninsula (Spain) consists of 22 taxa. New fieldwork has been done resulting in the description of new soil endemics and the discovery of new populations of this specialized flora. Consequently, bibliographical sources, databases such as the Global Biodiversity Information Facility (GBIF), and existing herbarium sheets have been revised. Crepis bermejana and Galatella malacitana have been added to the list and are proposed to be evaluated as threatened. Teucrium reverchonii has been excluded from the list. Euphorbia flavicoma subsp. bermejense and Armeria villosa subsp. serpentinicola required changes in nomenclature. These nomenclatural changes imply changes in population allocations. The revised list is composed of 23 obligate serpentinophyte taxa. Future conservation measures may include a complete Iberian (including Portugal) serpentinophytes checklist and corresponding revisions of States' legislation and Red Lists.

Peridotite outcrops have special lithological (serpentine) and soil characteristics; they also support an unique flora and vegetation "that clearly differ from that of other soil types. One of the most important peridotite outcrops in the Western Mediterranean Basin is located in Sierra Bermeja (Andalusia, Spain). The establishment of a complete ecological-floristic checklist of serpentinophytes in this area, and a comparison with other serpentine-endemic floras in the Mediterranean Basin, is essential for the assessment, management and conservation of these special areas. The recognition of serpentinophytes was made following six criteria used for floras inhabiting special substrata,. The list of species exclusively or partially found on peridotite comprises 27 taxa with a variable degree of serpentinophily: obligate serpentinophytes (obligate endemics), preferential serpentinophytes (populations located mainly on serpentine) and subserpentinophytes (with some populations located on magnesium-rich substrata). As observed in other Mediterranean outcrops, the number of obligate serpentinophytes increases with the area of the outcrop, and the genera Alyssum, Arenaria, Armeria, Centaurea and Silene were the most frequent. Most of the studied serpentinophytes, except for a few xerothermophilous taxa, present a wide bioclimatic (altitudinal) range and grow in shrublands and pastures in rocky places with shallow soils. As many as 56% of the serpentinophytes are threatened and, among obligate serpentinophytes, 45% are categorized as critically endangered or endangered, emphasizing the need for urgent conservation measures on the species and their habitats Based on this checklist, more detailed studies may focus on serpentinophytes for their particular physiology, adaptive traits, functional types, phenology and applications.

We studied a type of Californian ultramafic chaparral to determine functional groups which can help reduce the complexity of ecosystem management. The study was realized in McLaughlin Reserve, State of California, USA. We analysed the species of a serpentine plant association previously phytosociologically described in the area: Ceanotho albiflori-Quercetum duratae for their functional traits and functional groups. Traits per species were measured building a trait database. We used Principal Component Analysis to identify the combination of functional traits with major weight and a neighbor-joining clustering to define functional groups for this vegetation association. Our results indicated that the studied association is dominated by phanerophytes, with low degree of spinescence. Leaves were mainly malacophyllous with high degree of tomentosity, reduced size and a partial shedding of leaves was observed during summer. We considered six functional groups as the optimum number of clusters in a total of 18 species. The two first functional groups were composed of chamaephytes with brachyblasts and dolichoblasts with differences in the degree of tomentosity. The rest of the functional groups were composed of phanerophytes where the differences between them were based on traits in relation to the branches, leaf size and the horizontal development of the root system. The functional groups obtained show that this serpentine chaparral is composed of species with a wide range of functional traits. The study of other Mediterranean serpentine ecosystems in California and elsewhere could contribute to create new perspectives of functional ecology and help in the management of these valuable ecosystems.