Search

The ecological succession has been widely studied by means of biofouling assemblages among different substrates, and mainly targeted in early stages on artificial ones. The present study focuses on biofouling that colonizes carbonated structures, a material similar to the natural substrate produced by the electrolysis of seawater, which is relatively very little studied. We have observed the colonization of sessile macrofouling of the port of Alicante (SE Spain, Western Mediterranean) on two types of substrates (electrolytic carbonated and steel) over 12 months of succession. The assemblages of both substrates have been analyzed by means of diversity indexes and multivariate analysis (PERMANOVA and SIMPER) in order to see the differences over time. The carbonated substrate has presented a community with higher values of biological diversity, structure and complexity, although the differences in species composition between substrates are not evident during all immersion periods. Thus, these results seem to indicate that, even after 12 months of immersion, communities are still in a dynamic successional stage. [ABSTRACT FROM AUTHOR]

Wildfires have become increasingly prevalent and destructive in forest ecosystems worldwide, necessitating a comprehensive understanding of post-fire recovery dynamics for effective conservation and management. Remote sensing technology, coupled with vegetation indices such as Normalized Burn Ratio (NBR), Normalized Difference Vegetation Index (NDVI), Green Red Vegetation Index (GRVI), and Red Vegetation Index (RVI), offers a powerful means to investigate these processes. In this study, we utilize remote sensing techniques to conduct a comparative analysis of secondary ecological succession following wildfires in three distinct forest types (Coniferous, Sclerophyll, and Mixed) of a forest affected by fire near Moguer, Spain. Through the acquisition and analysis of multispectral satellite imagery, we monitored changes in vegetation health and recovery across the region of interest. The NBR index allowed us to assess the severity and extent of wildfire damage, while NDVI quantified vegetation greenness and regrowth. GRVI and RVI provided insights into subtle variations in vegetation composition and health. We identified distinct temporal and spatial patterns in post-fire recovery among the different forest types by applying these indices for the period between 2017 and 2021. Our findings underscore the significance of understanding the diverse responses of these ecosystems to wildfires. While common recovery patterns emerged, such as an initial decrease in NDVI followed by regeneration, variations were observed in the timing and magnitude of recovery. These distinctions are attributed to differences in species composition, fire adaptations, and ecological processes specific to each forest type. In conclusion, the utilization of NBR, NDVI, GRVI, and RVI indices allows for a more nuanced evaluation of post-fire recovery dynamics. [ABSTRACT FROM AUTHOR]

Context: The abandonment of traditional practices has transformed agro-pastoral systems, leading to a more frequent occurrence of passive rewilding of Mediterranean landscapes. Reconstructing ecosystem responses to climate under different grazing conditions (i.e., wild, and domestic ungulates) is important to understand the future of these ecosystems. Objectives: Here we study the different roles of domestic and wild herbivory in defining the climate-vegetation interaction. Specifically, we evaluated (1) the effect of climate on primary productivity at the landscape scale and (2) the long-term trends of vegetation biomass in response to passive rewilding or maintenance of traditional grazing systems. Methods: This study was carried out in South-eastern Spain. We used satellite images to generate NDVI time series that proxy primary productivity and vegetation biomass. We combined the NDVI and climate data from two key landscapes: one with wild ungulates and another predominantly with domestic ungulates. Results: We detected a secondary succession process in areas with only wild ungulates. In domestic herbivory areas, vegetation biomass remained constant throughout time (30 years). In domestic herbivory areas temperature and seasonal precipitation affected primary productivity. In areas with only wild herbivory, primary productivity was mainly driven by annual precipitation, and it was less dependent on seasonal precipitation. Conclusion: These results highlight the distinctive roles of herbivores in defining Mediterranean landscapes' adaptability to climate, through passive rewilding or traditional livestock use. Maintaining both ecosystems can enhance landscape heterogeneity and ecological sustainability in a context of climatic changes. [ABSTRACT FROM AUTHOR]

Tirez was a small and seasonal endorheic athalassohaline lagoon that was located in central Spain. In recent years, the lagoon has totally dried out, offering for the first time the opportunity to analyze its desiccation process as a "time-analog" to similar events occurred in paleolakes with varying salinity during the wet-to-dry transition on early Mars. On the martian cratered highlands, an early period of water ponding within enclosed basins evolved to a complete desiccation of the lakes, leading to deposition of evaporitic sequences during the Noachian and into the Late Hesperian. As Tirez also underwent a process of desiccation, here we describe (i) the microbial ecology of Tirez when the lagoon was still active 20 years ago, with prokaryotes adapted to extreme saline conditions; (ii) the composition of the microbial community in the dried lake sediments today, in many case groups that thrive in sediments of extreme environments; and (iii) the molecular and isotopic analysis of the lipid biomarkers that can be recovered from the sediments today. We discuss the implications of these results to better understanding the ecology of possible Martian microbial communities during the wet-to-dry transition at the end of the Hesperian, and how they may inform about research strategies to search for possible biomarkers in Mars after all the water was lost. [ABSTRACT FROM AUTHOR]

Although farmlands are the most extensive terrestrial biomes, the abandonment of traditional agriculture in many parts of the world has brought opportunities and challenges for the restoration of such human-disturbed habitats. Seed arrival is a crucial necessary ecological process during plant recolonization that can be enhanced by the use of the so-called "perch plants". Little is known, however, about whether the seed arrival via frugivorous birds is affected by the spatial distribution of the perch plants in disturbed habitats. To evaluate several spatial aspects of "perching" effect, we used a spatially explicit approach in two disturbed plots within the Doñana National Park (SW Spain). Specifically, we chose as study system the pioneer Mediterranean dwarf palm Chamaerops humilis L., which is often used as a perch by a variety of frugivorous bird species. A total of 289 C. humilis individuals were sampled in search of bird feces (N = 2998) and dispersed seeds (N = 529). Recorded seeds belonged to six different woody species from five different families. Nine bird species from six different families were recorded using C. humilis as perches. GLMs analyses indicated that taller C. humilis males with higher numbers of spatially associated woody species received more dispersed seeds. We detected a random spatial structure of bird feces and dispersed seeds in one study plot, while a nonrandom spatial structure was found in the other one, where isolated C. humilis received a higher number of bird feces and dispersed seeds than expected under spatial null models. The difference in spatial patterns between both study plots could relate, among other factors, to their different state of development in the ecological succession. Most of dispersed seeds were concentrated in a small number of C. humilis individuals, usually male and large ones, that acted as "hotspots" of seed arrival. The fact that frugivorous birds in one study site visited most often isolated C. humilis questions the aggregated spatial structure of revegetation designs typically used in restoration projects. This study reveals novel spatial aspects of the "perching" effect which could be helpful in the restoration of human-disturbed habitats worldwide. [ABSTRACT FROM AUTHOR]

The time‐based perspective of river‐floodplain processes plays a key role in understanding its evolution until its present situation and in guiding process‐based river restoration. However, despite the wide range of approaches to eco‐hydromorphological characterization, the analysis of fluvial dynamics and their drivers under a temporal perspective requires more investigation. For the present study, a historical analysis of river‐floodplain dynamics has been undertaken in a study section of the Duero River upstream of Zamora (Spain), within the framework of the DRAINAGE project for the integral management of flood risk. Aerial imagery for the period 1945–2017 was used to create habitat maps that were subsequently intersected to identify trajectories of habitat change (anthropization, changeless, progression, and regression). In addition, a Natural Trajectory Index (NTI) and an Anthropization Ratio (AR) were proposed as a way to assess the balance of natural trajectories (progression vs. regression) and the weight of anthropization versus the sum of natural trajectories, respectively. Results show a system with a high degree of stability and anthropization, and a current imbalance of natural trajectories with a predominance of progression in the ecological succession. Rejuvenation processes have to be reactivated through nature‐based solutions, allowing for more sustainable water management practices. This perspective aims at promoting a more resilient system. The diachronic analysis presented is widely exportable to other river‐floodplain systems as a basis for process‐based restoration practice. [ABSTRACT FROM AUTHOR]

Summary: Microbial communities in natural ecosystems are subject to strong ecological rules. The study of local communities along a regional metacommunity can reveal patterns of community assembly, and disentangle the underlying ecological processes. In particular, we seek drivers of community assembly at the regional scale using a large lacustrine dataset (>300 lakes) along the geographical, limnological and physico‐chemical gradients in the Pyrenees. By using high throughput amplicon sequencing of the 16S rRNA gene, and inferring environmental sources of bacterial immigrants, we showed that surface aquatic bacterial assemblages were strongly influenced by terrestrial populations from soil, biofilms or sediments, and primarily selected by a pH‐alkalinity gradient. Indeed, source proportions explained 27% of the community variation, and chemistry 15% of the total variation, half of it shared with the sources. Major taxonomic groups such as Verrucomicrobia, Actinobacteria and Bacteroidetes showed higher aquatic affinities than Parcubacteria, Gammaproteobacteria, Alphaproteobacteria or Betaproteobacteria, which may be recruited and selected through different hydrographic habitats. A regional fingerprint was observed with lower alpha diversity and higher beta diversity in the central Pyrenees than in both ends. We suggest an ecological succession process, likely influenced by complex interactions of environmental source dispersal and environmental filtering along the mountain range geography. [ABSTRACT FROM AUTHOR]

Two well exposed platform successions of late Early Aptian age developed in the central part of the Galve sub-basin of the Maestrat Basin: the highstand ‘Camarillas–El Morrón’ platform, and the succeeding ‘Las Mingachas’ small lowstand platform, built out downslope in the former basin. Both platforms had a flat-topped non-rimmed depositional profile, showing similar platform-top to slope biofacies, which are described here in both qualitative and quantitative terms. The proximal platform top succession is characterized by a Toucasia -dominated rudist association. The margins of the two platforms consist of massive limestone characterized by a Polyconites -dominated association, in which clusters of Polyconites hadriani in life position are joined by both branching and domal corals, as well as the oyster-like Chondrodonta and nerineid gastropods. In Las Mingachas platform, where the massive rudist- and coral-rich platform limestones pass laterally into the slightly more marly and recessive clinoforms of the upper slope facies, Polyconites is especially abundant. Basinwards these slope deposits pass into basinal marls with orbitolinids and ammonoids. The distribution of the two distinct rudist associations recognized here is attributed to the different environmental tolerances of the rudists with respect to such factors as current regime and rate of sedimentation. The prevalence of polyconitids, in place of caprinids, in these late Early Aptian platform margin facies makes a striking contrast with older, earliest Aptian platforms. [ABSTRACT FROM AUTHOR]

Mediterranean humid mountains are ecological hotspots with high water availability that may accelerate their recovery after farmland abandonment, a widespread phenomenon in marginal areas of the European Mediterranean Region. This land use change led to secondary succession processes triggering changes in soil properties and soil microorganisms. This is the first study in assessing the environmental influence of both ecological succession and parent material over soil properties and soil bacterial communities in these habitats. To examine the effects of secondary succession and elucidate the role of parent material in soil bacterial communities, six soil plots were sampled from the combination of abandoned and rainfed olive groves, terraced or non-terraced, and over four parent materials in Lluc Valley, a Mediterranean hyper-humid mountainous area on the island of Mallorca, Spain. Soil bacterial diversity and taxonomic composition at phylum and family level in each field were analyzed by rRNA 16 S amplicon sequencing. In addition, a series of soil physicochemical and microbiological properties, together with enzyme activities were assessed. Results showed that secondary succession and parent material significantly affected soil physicochemical and microbiological properties, soil enzyme activities and soil bacterial communities' diversity and taxonomic composition. Secondary succession following farmland abandonment triggered higher total organic carbon (TOC), microbial biomass carbon (C mic), basal soil respiration (REB), alkaline phosphatase activity (Php) and dehydrogenase activity (DHA), thus enhancing soil quality. In contrast, parent material significantly shaped pH, specific surface area (SSA), TOC, C mic , REB and soil enzyme activities, playing a key role in land use effects modulation. According to the distance-based redundancy analysis (db-RDA), SSA, TOC, REB, C mic , urease activity (Ur) and Php were the soil properties that contributed to significant changes in bacterial communities' composition at the family level. This study evidenced that farmland abandonment led to improve soil quality in Mediterranean humid mountains, with positive feedbacks provided by parent material. • Farmland abandonment triggered higher TOC, C mic and REB, enhancing soil quality. • Lithology significantly shaped pH, SSA, TOC, C mic , REB and soil enzyme activities. • β-diversity analyses showed changes due to secondary succession and parent material. • Significant relationships were found between soil properties and bacterial families. [ABSTRACT FROM AUTHOR]

Cretaceous climate records provide evidence that major volcanic pulses with duration of 10 3 to several 10 5 yr triggered changes in climate and oceanography. Black shales of Oceanic Anoxic Event 1b ( ca. 113–109 Ma) are regarded as signatures of late Aptian greenhouse pulses associated with volcanic episodes. New TEX86 paleotemperature record indicates that warm Aptian climate was interrupted by repeated cold snaps alternating with described greenhouse pulses. An extraordinary thick shallow-water carbonate succession of the Aralar Platform from the southeastern Basque–Cantabrian Basin in Spain provides a unique opportunity to test the hypothesis that cold phases interrupted warm climate in the Aptian. Platform evolution is traced through time of the proposed Aptian cold snaps alternating with greenhouse episodes. New high-resolution C-isotope records established in the studied upper Aptian platform carbonates serve as chemostratigraphic tool providing a link between carbonate-platform evolution, basinal black-shale formation and associated changes in open ocean palaeotemperatures. The late Aptian cold snaps find their expression in a remarkably reduced neritic succession, punctuated by several emersion horizons formed during sea-level lowstands. The studied section bears evidence for several episodes of choked carbonate production related to increased runoff at times of sea-level rise, during which orbitolinids bloomed in a sediment-loaden lagoonal setting. These intervals coincide with the deposition time of organic-rich Kilian and Leenhardt levels belonging to OAE1b. [ABSTRACT FROM AUTHOR]

1. In Mediterranean mountainous areas, forests have expanded in recent decades because traditional management practices have been abandoned or reduced. However, understanding the ecological mechanisms behind landscape change is a complex undertaking because the influence of land use may be reinforced or constrained by abiotic factors such as climate. In this work, we evaluated their combined effects on recent forest expansion across climatic, topographic and management gradients. 2. We used orthorectified aerial photographs from the second half of the twentieth century (1956, 1974, 1983, 1990 and 2004) to monitor changes in forest distribution in a set of 20 head-water basins in the Cantabrian Mountains of north-west Spain, at the Eurosiberian-Mediterranean limit. In particular, we evaluated the role of land-use history (comparing natural vs. anthropic basins) and microclimate (comparing shaded vs. sunny aspects) of forest gain/loss rates and spatial distribution shifts. Finally, we applied Species Distribution Modelling techniques (MaxEnt and BIOMOD) in the stated scenarios of land-use history and microclimate, to assess habitat suitability for forest expansion on the basis of topography, soil properties and mesoclimatic variables. 3. Forest cover increased from 10.72% in 1956 to 27.67% in 2004 in the area. The rate of expansion was significantly higher in natural basins and, particularly, on shaded slopes. In all cases, the mean elevation of new forest patches increased during the study period, which was particularly evident on natural sunny slopes. The performance of the models and the magnitude of the effects varied across land-use histories and microclimatic conditions. Soil properties and temperature and precipitation in late spring and early summer were the main drivers of forest expansion in modelling exercises, although expansion rates and upward altitudinal shifts were primarily controlled by landuse history and the biogeographic origin of the forests. 4. Synthesis. The combination of monitoring and modelling techniques used in this work contributed to the understanding of forest expansion in cultural systems, indicating that ecological succession is not a homogeneous process, but varies spatially due to human and abiotic constraints since historical times. [ABSTRACT FROM AUTHOR]

The mechanisms responsible for species replacement during ecological successions is a long-standing and open debate. In this study, we examined the distribution of the Sardinian warbler Sylvia melanocephala along two grassland-to-forest gradients, one in a high-diversity area (Albera-Aspres chain in Catalonia: eight Sylvia warbler species) and one in a low-diversity area (Mount Hymittos in Greece: four species). In Catalonia, distribution models suggested that the apparent exclusion of S. melanocephala from the open and forest ends of the gradient may be explained entirely by the preference of S. melanocephala for mid-successional shrublands. However, a joint analysis of both data sets revealed that: 1) S. melanocephala was more evenly distributed along the vegetation gradient in Greece, suggesting ecological release in the low-diversity area; and 2) a distribution model assuming interspecific competition (based on the distribution of Sylvia species showing a negative co-occurrence pattern with S. melanocephala) had a significantly higher predictive ability than a distribution model based on habitat variables alone. Our study supports the view that species turnover along ecological gradients generally results from a combination of intrinsic preferences and interspecific competition [Current Zoology 57 (3): 307–317, 2011]. [ABSTRACT FROM AUTHOR]

Abstract: Because of their rapidly changing vegetation dynamics and harsh environmental conditions, roadside prairies in semi-arid regions represent an exceptional study system in which to investigate the effects of plant-soil interactions on ecosystem functioning. We conducted a two-year field experiment on two roadside embankments in semi-arid central Spain differing in construction age to answer the following questions: (i) do commonly used restoration treatments (hydroseeding, fertilization and irrigation) affect soil microbial functional diversity and processes related to soil functioning (basal respiration, total N and P and in situ N availability rate)? (ii) what portion of plant effects on processes related to soil functioning is mediated indirectly by microbial functional diversity? Except for a small and negative irrigation effect on the microbial functional diversity in the three-year old site, the restoration treatments employed did not affect this variable. Fertilization increased plant diversity, an effect likely mediated by the enhanced soil nutrient availability with this treatment at early stages of secondary succession. In contrast, hydroseeding did not affect processes related to soil functioning. The total effect of the plant community on these processes was higher than that of the microbial functional diversity alone, suggesting that the studied slopes are to the greater extent regulated by plants. However, soil microbes are a key proximate influence in the system, as the indirect effects of plant community on soil functioning processes mediated by soil microbes represented 37–41% of the total plant effects observed. Our results indicate that the restoration of recently built slopes can potentially be improved with treatments that promote plant compositional shifts, such as fertilization, or alter soil function, such as the enhancement of soil microbial functional diversity. They also highlight that plant-soil interactions are an important process that can be manipulated for restoration purposes in early-successional stages, especially in nutrient-poor semi-arid ecosystems. [Copyright &y& Elsevier]

Abstract: A total of 445 pockmarks were observed on the upper continental slope of the northwest corner of the Iberian Peninsula (the Ortegal Spur area) by swath bathymetric and ultrahigh resolution seismic data. The pockmarks are U-, V- and W-shaped and have terraces or indentations in cross-section, and are dish-shaped (circular to oval) in plan view. They occur on the surface of the seabed and buried within the Plio-Quaternary and Neogene sediments. Four types of pockmarks were identified and mapped on the basis of their plan-view and cross-section morphology: regular, irregular, asymmetric and composite. The concentration of pockmarks is attributed to seepage of fluids migrating up-dip from deeper parts of the sedimentary basin. A linear high-density concentration with a NNW to N, NE and ESE trend of pockmarks is observed above inferred basement faults that do not affect the Quaternary succession. These pockmarks are thus caused by seepage of thermogenic gas and/or other pore fluids from deeper Late Cretaceous units, and their distribution may help to improve our understanding of the fluid system and migration regime in this part of the Galicia continental margin. [ABSTRACT FROM AUTHOR]

Abstract: The initial colonization phase is the crucial start point for succession and therefore for restoration. However, little is known about abiotic factors that influence the early stages of revegetation dynamics on restored coal mines, particularly in a Mediterranean climate. This information is crucial for improving our ability to reclaim land despoiled by mining. Here, we characterized the short-term plant community development in the first 3 years after hydroseeding on a topographically diverse reclaimed open-pit coal mines in Spain. Topography influenced both community composition and diversity producing different trajectories between the three different aspects (north-facing, south-facing, flat). Hydroseeded species provided most of the initial vegetation cover, which brought about most of the compositional differences between these aspects. We also found that the changing climate through the growing season also influenced floristic composition and diversity. Summer drought reduced the cover of hydroseeded perennial species and allowed native species to colonize. These results emphasize the need to take topography into account when developing reclamation management plans in Mediterranean ecosystems, and an acknowledgement that climate might drive the succession in the desired direction, hence increasing success in restoring mining impacts. [Copyright &y& Elsevier]

Abstract: We present benthic foraminiferal assemblage data from an exhumed Miocene canyon and fan system from the Tabernas Basin (SE Spain). The presence of good indicator taxa and unique assemblages occupying specific environments allows the distinction of slope, canyon and fan environments within the Tabernas Basin by foraminiferal assemblages alone. Five assemblages are defined on the basis of the occurrence of the indicator taxa. Primary control on the distribution of these assemblages is consistent with trends of physical disturbance and consequent defaunation. Barren samples, which are predominantly found in high-energy parts of the proximal canyon, are recognized as representing recently defaunated substrates (i.e. early successional assemblages). High diversity assemblages containing a high abundance of agglutinated taxa are recognised in the undisturbed slope sequences as being the regional equilibrium (“climax”) fauna. Intermediate between these end-members are assemblages with low diversity, dominated by calcareous taxa typically found in the relatively low-energy canyon and fan environments, which are recognized as representing the middle phases of the ecological succession. Two further assemblages, a low diversity assemblage typified by Cassidulina laevigata and Bulimina costata and a very low diversity assemblage dominated (>10% of all benthic tests) by Globobulimina spp., are restricted to low-energy parts of the canyon and fan, and are absent from the proximal canyon and slope. The composition of these assemblages indicate that nutrient supply/oxygenation is a secondary control on the palaeoecology of the canyon system. A conceptual model for the recolonisation of defaunated substrates in El Buho Canyon is proposed, in which either an oligotrophic climax assemblage or a eutrophic climax assemblage can be achieved at the completion of recolonisation of defaunated substrates, depending on environmental conditions. [Copyright &y& Elsevier]

The process of fungal community succession in forests is still insufficiently known, especially in Mediterranean ecosystems. To reveal successional patterns, we studied changes in aboveground sporocarp composition in managed Pinus pinaster Ait. forests across a stand age chronosequence from 5 to more than 90 years in Soria province (Central Spain). We evaluated the effect of yearly conditions and stand age on species richness, composition, and trophic groups. All aboveground sporocarps were collected and identified in 21 plots, each measuring 150 m2, placed in a random stand age-stratified survey. Sampling was performed weekly in the autumn during 6 years (1997–2002). The effect of year and stand age on species richness was analysed using repeated measures analysis of variance and change in composition. Changes in community composition were evaluated via canonical correspondence analysis (CCA). The response of different trophic groups was analyzed using ANOVA with age as a fixed factor. Fungal community richness increased with stand age. This increase was related to the rise in humicolous saprotroph and mycorrhizal species. The presence of parasitic and lignicolous fungi was always very low, probably as a result of forest management. Yearly conditions exerted a stronger effect than stand age on aboveground sporocarp community richness and composition. [ABSTRACT FROM AUTHOR]

Abstract: Differences in size and species diversity were analysed in a zooplankton community of a Mediterranean salt marsh (Empordà wetlands, NE Iberian Peninsula), where the dominance of a single species was frequent. In the permanent salt marsh, species diversity and size diversity had similar patterns along zooplankton succession. In the temporary salt marsh species diversity was high after flooding and diminished once water inputs ceased. As species diversity declined size diversity increased. Eventually, one species of calanoid dominated the zooplankton community. The high size diversity in situations of calanoid dominance was possibly due to the co-occurrence of different developmental stages, each of which have different diets. Size diversity would thus indicate trophic niche segregation among different sizes. The combined use of species and size diversity values allows the identification of the successional phases. [Copyright &y& Elsevier]

Studies saltmarsh succession by observing the interaction between Spartina maritima grass and Arthrocnemum perenne shrubs in the coastal marshes in Huelva, Spain. Impact of the construction of a dike in 1977 which divided the saltmarshes; Effect of the primary colonization of S. maritima to the successful invasion of A. perenne.

Mining activities on metal sulphide ores are considered one of the most environmentally damaging anthropogenic activities worldwide, mainly due to the production of metal(loid)- enriched tailings. The objective of the work was to elucidate which factors, including edaphic, vegetation and microbiological aspects, determine soil functionality in the phytomagement of mine tailings piles in semiarid areas. For this purpose, a field study was conducted using a transect experimental design in a former mining area located in southern Spain. Soil characteristics, including edaphic parameters, bacterial and fungal compositions, were determined. The variation in edaphic parameters (pH, electrical conductivity, organic carbon, particle size distribution, etc) through the deterioration transect caused a decrease in plant and microbial diversities, as well as in microbial productivity measured by enzymatic activities. Variation in bacterial relative abundances through the transect was better explained by soil fertility related factors, such as organic matter, pH, salinity, enzymatic activities or microbial biomass (which in turn were related to the presence of plants), than by metals concentrations. The presence of vegetation at the tailings allowed the transition from lithotrophic bacterial orders which dominated in bare tailings areas (e.g. Acidimicrobiales , Chromatiales) to organotrophic oriented orders (e.g. Cytophagales , Actinomycetales). Vegetated patches at the tailings pile and its borders shared some organotrophic bacteria with control forest samples (e.g. Rhizobiales), indicating that natural plant mediated successional processes might stimulate biogeochemical cycles similar to those occurring at non-polluted systems. This functionality of the impacted sites, which include unfavourable edaphic conditions, should be taken into account in the phytomanagement of mine tailings, since it may support its long-term sustainability. Unlike bacteria, variations in fungal relative abundances through the transect were not clearly explained by soil parameters or the presence of plants. Other factors related to spatial distribution or the type of organic substrates may be more determinant in the case of fungi. Image 1 • A gradient determined by organic matter, salinity and metal concentrations occurred. • Bacterial abundance was better explained by fertility factors than by metals. • Plants caused transition from lithotrophic to organotrophic bacterial orders. • Variation in fungal abundance was less dependent on soil factors. [ABSTRACT FROM AUTHOR]

Mediterranean semiarid areas are suffering a growing process of agricultural abandonment that represents a challenge for restoration. Limited seed arrival, drought, and scarce suitable microhabitats in oldfields make plant colonization difficult. Restoration through ecological succession can take advantage of increased seed dispersal through animal vectors, but precise knowledge of the factors involved (e.g., seed disperser behavior, rate of effective recruitment of dispersed seeds, and effectiveness of the applied restoration structures) is critical. Otherwise, efforts to foster the processes of interest may be misdirected. We propose and test a methodological approach based on the combination of ecological (bird censuses and camera trapping) and genetic tools (DNA barcoding), to assess seed dispersal of fleshy‐fruited shrub species by birds toward oldfields in one of the driest areas of southeastern Spain. We assisted natural restoration with artificial bird attractors (perches and water troughs) in two abandoned areas with different ages. Furthermore, we provided microenvironments (rocks) and prevented herbivory (by fencing) to enhance plant recruitment. Results revealed strong differences among assessment techniques in the characterization of dispersal interactions. While bird censuses only informed about frugivores occurrence, camera trapping and barcoding enabled the quantification of species responses. Attractors proved to be effective in triggering a quantifiable seed arrival, but no subsequent plant establishment occurred. We highlight the importance of implementing different techniques to characterize and assess avian seed disperser performance. Water provision increased seed arrival, but our design failed to enhance plant recruitment. The next logical step in the restoration of Mediterranean oldfields is the optimization of conditions for seed germination and successful plant establishment. [ABSTRACT FROM AUTHOR]