Northwestern Iberian Peninsula Research Articles

Prehistoric and Early Roman Period Goldwork from Northwestern Iberia: An Analytical Study of Artefacts from the Archaeological and Historical Museum of A Coruña

This article presents the results of a topographical and analytical study using hh-XRF of 22 gold and gilded objects from the Archaeological and Historical Museum of A Coruña (Galicia, Spain). They are highly representative of the northwestern Iberian goldwork from the Chalcolithic (third millennium BC) to the early Roman period (first century AD). This study contributes to our knowledge of the production techniques used in those periods, as well as their evolution over time. The collection includes some of the most representative types in this area, such as Early Bronze Age “sheet collars” and torcs from the Second Iron Age. In the case of torcs, new data are provided on one of the formally best-documented types (the Artabrian type) and on those known as “Baroque torcs” that are characteristic of the final moments of this goldsmith tradition. While pieces from the Chalcolithic and Early Bronze Age were made with alluvial gold, the torcs from the Late Iron Age contain variable amounts of silver and copper. Also detected is the frequent use of cores made of less precious metals, which were subsequently given a golden appearance using gilding techniques. The new data are discussed in light of our current knowledge of NW Iberian goldwork, one of the most representative of this craft tradition in Western Europe for those periods.

Complementarity of offshore energy resources on the Spanish coasts: Wind, wave, and photovoltaic energy

The complementarity of the solar, wind, and wave energy resource in hybrid offshore platforms has the potential to increase productivity and reduce the variability in the energy output that a single type of energy source can generate. In this study, ERA5 reanalysis is used to calculate wind, solar and wave energy resources in Spanish potential locations for offshore platforms. The results indicate that wind energy presents the largest energy resource for all Spanish offshore regions, followed by photovoltaic energy. However, taking in count the “drought periods” (periods in which no energy is obtained from any of the analysed technologies), wave energy presents an opportunity to provide a continuous flow of energy, especially in the northwestern Iberian Peninsula and the Canary Islands. The evaluation of the complementarity of the three energy sources shows that the use of hybrid platforms would not only increase energy production but also reduce variability. In terms of energy production, wind energy along with solar energy are the largest energy generators. But in terms of minimizing variability, wave energy along with solar photovoltaic energy are the most important. Thus, this study is paving the way to introduce multiple energy converters on hybrid platforms as a pathway toward more powerful and sustainable energy production.

Potentially toxigenic phytoplankton patterns in the northwestern Iberian Peninsula

The Galician estuaries are Europe’s foremost supplier of mussels, generating millions of euros annually and offering substantial employment opportunities for its population. One of the most critical threats to shellfish production is the occurrence of harmful algal blooms (HABs), contaminating bivalves with phytotoxins. To successfully tackle this problem, there needs to be a collaborative effort between the scientific community and decision-makers to establish a dynamic and effective monitoring system. This could enable early warnings and preventive actions to avert the loss of millions of tons of shellfish. Remote sensing, despite its limitations, requires commitment and effort by experts to devise effective methods for detecting target optical constituents mixed with other undesired target but that exhibit strong signals. Therefore, the essential necessity arises to identify approaches for mitigating the shortcomings of the undertaken efforts. The objective of this study is to assess the main environmental drivers of potential harmful genera (Pseudo-nitzschia, Dinophysis, Alexandrium, and Gymnodinium) in the Rías Baixas from 2015 to 2022, developing regression-based models and customizing Generalized Additive Models (GAMs) to investigate their spatial-temporal dynamics. Risk-susceptible bloom zones were identified in the river mouth of the Ría Pontevedra and from the center to offshore of the Ría Vigo. Early upwelling events triggered peaks in chlorophyll-a (Chl-a), driving Dinophysis grazing on phytoplankton communities mainly dominated by diatoms, flagellates, and ciliates. Subsequently, the upwelling intensity favoring Pseudo-nitzschia or Alexandrium minutum growth as larger diatoms declined. A. minutum exhibited elevated incidence over the past five years. Gymnodinium catenatum presented a rare occurrence across the three studied estuaries, which limited the assessment of its spatial dynamics in the region. This study emphasizes the need to integrate remote sensing evaluation of high-risk bloom areas (July to September), in-situ cell count collection, and enhanced efforts for forecasting future critical occurrences of HABs.

Unveiling Local Power Through Microhistory: A Multidisciplinary Analysis of Early Modern Husbandry Practices in Casaio and Lardeira (Ourense, Spain)

Abstract Following the proposal for the special issue, the aim of this study is to reflect on the potentialities and setbacks of a micro-historical approach to the archaeological record. This will be done by analysing the local organization of Early Modern husbandry in a territory in northwestern Iberia, where investigations have been carried out since 2017. I will apply the theoretical background of microhistory to four specific archaeological sites to delve into the social structuring and power relationships among the different agents involved in stockbreeding in the territory. In this regard, I will argue that one of the most compelling contributions of microhistory is to delve into the deep connection between the systemic and the quotidian, between structure and agency. However, this connection is not always straightforward and visible in the sources, and thus a deep theoretical and methodological background becomes necessary to understand questions such as how power was conceived and articulated at the local level and in daily life.

Estimating spatial variability of baseline isoscapes from fish isotopic signatures at the community level

One of the main limitations in the application of stable isotopes to marine trophic ecology is obtaining a reliable baseline upon which to calculate isotopic enrichment. Isotopic baselines are variable in space and time, influenced by several environmental factors such as terrestrial runoff, oceanic currents or primary production, and thus, investigating their patterns of variability is essential to gain confidence in the estimates of trophic position based on isotopic signatures. We here propose a multispecies and multitrophic approach to study baseline isoscapes for nitrogen (δ15N) and carbon (δ13C), which we test on the demersal community of the Northwestern Iberian Peninsula. Using a set of 372 isotopic data of 11 demersal fish species sampled during autumn, we modelled the spatial variability of the isotopic baseline (for δ15N and δ13C separately) by removing the biological effect of species identity and individual length. Using the residuals of these models, which represent the isotopic baseline anomalies, we investigated the effect of environmental variables in driving the observed spatial patterns. Our results identify clear and consistent spatial patterns for the δ13C isotopic baseline. This isoscape achieved the lowest values in the westernmost part of the study area (Galician coast) increasing towards the east (Cantabrian Sea). This spatial pattern was mostly driven by primary production and organic matter in the sediment, reflecting the influence of upwelling intensity in the δ13C isotopic baseline over the study area. Baseline isotopic anomalies of δ15N, on the other hand, did not show clear spatial patterns, suggesting that for this isotopic baseline spatial patterns at the regional scale might not be as consistent. Our study brings forward the potential of multispecies isotopic data for approximating the environmental isotopic baselines for the whole ecosystem.

The influence of databases enrichment using local macroinvertebrate genetic references for metabarcoding based biodiversity studies in river monitoring

Water resources play a vital role in sustaining ecosystems, human life, food security, and biodiversity. However, these resources currently face serious threats caused primarily by human activities. Because of that, European Union have mandated that all its member states monitor the ecological status of their water bodies. One of the most commonly used bioindicator groups for routine river biomonitoring is benthic macroinvertebrates, which rely mainly on morphological identification at the family level and the use of diverse indices to estimate the ecological status of the river ecosystem. The morphological approach has certain limitations, and metabarcoding is now considered an alternative technique for biodiversity studies and biomonitoring of surface waters. However, the efficacy of this approach depends on the comparison of sequencing data with genetic databases, which are often incomplete and geographically biased. In this study, we collected 92 macroinvertebrate samples from rivers in the northern Iberian Peninsula to identify all possible species and generate new DNA sequences for the COI-5P region. The objectives were to perform region-specific enrichment of reference databases for the geographical area of northern Spain and to assess the impact, before and after this strategy, on the taxonomic assignments used for ecological status inference in metabarcoding samples. The results showed that 21% of morphospecies lacked reference sequences in the BOLD or GenBank databases, indicating that a significant number of macroinvertebrate species in the northwestern Iberian Peninsula lack reference sequences in major genetic databases. Enriching the BOLD databases with new sequences led to the detection of an average of 17.25 more BINs (species-assimilable gene cluster) and 1.54 more IBMWP taxa (river ecological status indicator macroinvertebrate taxa) per sample, causing changes in the ecological status determination for 16% of the samples, which clearly shows that improving the databases with local species sequences could enhance the detection and identification of new IBMWP taxa, potentially impacting ecological status inference from molecular data. Additionally, a historical analysis of Iberian macroinvertebrate addition in the BOLD database using public BOLD records revealed an asymptotic trend that can be partially mitigated by region-specific enrichment. These results indicate that a local biota sequencing effort can considerably improve metabarcoding results rather than waiting for a gradual improvement of genetic databases. In conclusion, we advocate for a creation an Iberian freshwater macroinvertebrate checklist and then the initiation of a coordinated effort for sequencing any unsequenced species from the region.

A new genus and species of deep-sea Coralliidae (Octocorallia) from the northeastern Atlantic, the first polymorphic octocoral genus with a membranous-stolonate colony growth form

During bathyal samplings undertaken by the Spanish Institute of Oceanography, a new genus and species of trimorphic Coralliidae was collected from the Avilés Canyon System, the Le Danois Bank (Bay of Biscay) and the Galicia Bank (north and northwestern Iberian Peninsula, northeastern Atlantic). Mollecorallium aenigmaticum gen. nov., sp. nov. is described and illustrated, including a molecular study. It has retractile autozooids within small mounds, and an abundance of radiates and crosses morphologically very similar to those occurring typically in species from other genera of the family with a calcareous axis of cemented sclerites. However, the new species is exceptional in lacking an axis, growing instead as small membranous and stolonal colonies, and in having mesozooids in addition to siphonozooids. According to our molecular study, the new genus herein proposed is strongly supported by the phylogenetic distance from soft-coral and gorgonian growth form genera in the family. Despite the notable biodiversity of the octocoral bathyal fauna of the Bay of Biscay and nearby areas, new species are discovered whenever exceptional sites such as submarine canyons and seamounts are sampled.

Predator and pollinator? An invasive hornet alters the pollination dynamics of a native plant

Invasive vespids are able to disrupt native species assemblages, modify ecological dynamics, and degrade ecosystem services. However, it is often difficult to quantify such effects within invaded ranges, principally due to the complexity of interactions, and a lack of comparative pre-invasion controls. In this study, we thus examine the effects of an invasive hornet, Vespa velutina, upon native species densities and pollination in a major food plant, Hedera hibernica. Using the highly heterogeneous distribution of V. velutina in a coastal area of the northwestern Iberian Peninsula, we assessed the impact of differing hornet abundance on insect diversity, flower visitation frequency, and predator-prey interactions. We then examined resultant effects upon the pollination success of H. hibernica, in the form of fruit and seed set. Our results demonstrated that in areas with high V. velutina abundance, the floral visitation frequencies and durations of insect pollinators were significantly altered. Effects varied widely across insect families, reflected in the differing predation success rates of V. velutina upon various native pollinators, in tandem with competitive exclusion. Interestingly, V. velutina was itself a frequent floral visitor, becoming the most common nectar forager in areas where it was abundant. In spite of this, H. hibernica reproductive success was significantly degraded in these areas, resulting in reduced seed set. As such, V. velutina appears to have multidirectional effects upon pollination services, first as an insect predator, and second as a nectar competitor and pollinator. Crucially, our findings suggest that V. velutina is an inferior pollinator when compared to the native species that it displaces, resulting in a net reduction in pollination efficacy, and hence reproductive success in H. hibernica. This study thus reveals the profound effects of an invasive vespid on native species through both competitive and predatory interactions.

Nestedness Patterns of Amphibian Assemblages in Northwestern Iberia along an Altitudinal Gradient: Implications for Conservation

Nestedness Patterns of Amphibian Assemblages in Northwestern Iberia along an Altitudinal Gradient: Implications for Conservation

Relationship of seasonal variations in drip waterδ13CDIC,δ18O, and trace elements with surface and physical cave conditions of La Vallina cave, NW Spain

Abstract. Cave-monitoring studies clarify the climatic, surface vegetation, and karst processes affecting the cave system and lay the foundation for interpreting geochemical stalagmite records. Here we report the monitoring of cave air, bedrock chemistry, and drip water δ13CDIC, δ18O, and δD, as well as 16 trace elements, covering a full annual cycle spanning the 16 months between November 2019 and March 2021 in La Vallina cave in the northwestern Iberian Peninsula. While decreased rainfall and increased evapotranspiration in the summer months lead to a strong reduction in drip rates, there is little seasonal variation in δ18O and δD in a given drip, likely reflecting the discrete moderately mixed to well-mixed karst water reservoirs. Small differences in δ18O and δD between drip sites are attributed to variable evaporation intensity and/or transit times. The carbon isotope signature of the dissolved inorganic carbon of drip water (δ13CDIC) is likely driven by seasonal changes in the temperature controlling biological processes (vegetation and microbial soil activity), resulting in minimum δ13CDIC in summer and autumn months. Increased bedrock dissolution due to higher soil pCO2 in summer and autumn results in increased trace element concentrations of congruently dissolved elements. Cave air measurements (pCO2, δ13Cair, and temperature) indicate the seasonal ventilation (winter) and stagnation (summer) of cave air. The opposite effects of reduced cave air pCO2, seasonally variable biological activity, and increased drip rate limit the extent of the seasonal variation in degassing and prior calcite precipitation (PCP) supported by trace elements (Sr/Ca index). Estimated stalagmite growth rates using monitoring data suggest biannual phases of potential calcite precipitation in summer and winter and growth cessation during spring and autumn, depending on cave and drip water conditions and the location within the cave, which has important implications for the proxy interpretation of stalagmite records.

Pleistocene Glaciations of the Northwest of Iberia: Glacial Maximum Extent, Ice Thickness, and ELA of the Soajo Mountain

Soajo Mountain is located in the northwestern Iberian Peninsula near the border between Portugal and Spain. Its highest elevation is 1416 m at the Pedrada summit. During the Pleistocene, the cascade cirques on the east flank and the icefield that covered the flattened surface of the high plateau generated several glacier valleys. This study presents a paleoglacial reconstruction of the relict glacial landscape in Soajo Mountain for the Glacial Maximum Extent (GME) through the following methods: (1) a detailed geomorphological map supported by high-resolution orthophotography, digital elevation models with a spatial resolution of 70 cm, and field surveys; (2) the delineation of the glacial surface, and the calculation of the glacial flowlines to obtain the numerical model of the ice thickness; and (3) an estimation of the paleoELA altitudes. The paleoglacial reconstruction, using GlaRe methodology, reveals a glacial surface of 16 km2, including an icefield on the Lamas de Vez plateau (mean elevation of 1150 m) and a radial glacial flow to the east and north. The arrangement of the glaciated area attests to the topographic, lithological, and structural conditioning on the development of small glacial tongues, with an emphasis on the ice tongue flowing northwards, with a thickness of 173 m and a length of 2.92 km. The Soajo GME paleoglacier comprises three main glacial sectors: Lamas de Vez Icefield, Vez and Aveleira Valleys, and the Eastern Glacial Sector. These paleoglaciers have achieved maximum ice volumes of 214.4 hm3, 269.2 hm3, and 115.8 hm3, respectively, with maximum ice thicknesses of 127 m, 173 m, and 118 m, respectively. On the west flank, a smaller paleoglacier named Branda da Gémea recorded an ice volume of 24.3 hm3 and a maximum ice thickness of 110 m. According to the ELA-AABR method, Soajo Mountain has one of the lowest ELA values in the Iberian NW, ranging from 1085 to 1057 m. This is due to its oceanic location, an orographic barrier effect, and the influence of the polar front.

Massive incision and outcropping of bedrock in a former braided river attributed to mining and training

This research analyses multiple anthropogenic pressures in the Bernesga River, a gravel-bed river in Northwestern Iberian Peninsula. Among the causes of river incision in Bernesga River are extensive mining during the second half of the twentieth century, a ∼100 years-long history of channelization and river training starting around 1900, and to a lesser extent, land-use changes in the basin. As a result of these impacts, reach-averaged incision exceeds 8.5 m. Severe incision occurred simultaneously with a dramatic change in channel pattern: from ∼450 m-wide braided morphology around middle of the twentieth century to a narrow single-thread (∼40 m wide) channel in 2017. Quaternary alluvial deposits have been mostly depleted exposing the underlying bedrock. Unlike other rivers, bedrock outcrops have not stopped incision. Extremely narrow channels (∼12 m wide) have developed and incised at rates of ∼0.11 m/yr into bedrock materials, headcuts have formed on bedrock deposits and have rapidly retreated (at 33 m/yr) and the channel has incised forming adverse slopes under the presence of bed sills. Cause-effect relationships of cumulative impacts have been established between the recent evolutionary trajectory of the Bernesga River and multiple and simultaneous anthropogenic pressures.

Lead isotope fingerprinting techniques help identify and quantify 3000 years of atmospheric lead pollution from Laguna Roya, northwestern Iberia

Legacy pollution research has established that over the past 3000 years, mining and metallurgical activities have resulted in widespread deposition of lead (Pb) pollution. However, there is still a limited understanding of how humans have impacted the long-term cycling of Pb in the environment. We present a 4,000-year lake sediment Pb isotope record from Laguna Roya, northwestern Iberia, that identifies and quantifies the predominant sources of atmospheric Pb pollution. For the first time, Pb isotopic compositions of ancient slag samples dated (∼600 BCE–200 CE) from a mining district in the southwest of the Iberian Peninsula are compared to Pb isotope ratios of Pb pollution deposited contemporaneously in lake sediments. In addition, literature Pb isotope ratios of ores from mining regions throughout Iberia are compared with those of leaded gasoline and coal to identify additional sources of anthropogenic Pb. Deposition of atmospheric Pb pollution begins after 950 BCE, and until 1750 CE, the Pb isotopic composition most resembles the southwestern slag deposits, containing a mixture of Pb ores from southeast Iberia (up to 36%) and southwest Iberia (∼74%). Between 1750 and 1960 CE, Pb pollution is attributed to Pb mining in southcentral Iberia. After 1960 CE, the dominant Pb pollution source (∼85%) is again metal refining in southwestern Iberia, and only ∼15% is from leaded gasoline. Provenance and reconstruction of the temporal and spatial distribution of legacy Pb pollution further our understanding of how humans have affected the biogeochemical cycle of this toxic element in the environment over time.

Challenges of copro-parasitological surveys in wild Iberian ibex (Capra pyrenaica) populations addressed through a combination of molecular and statistical tools.

Copro-parasitological surveys in wildlife face challenges due to the secretive nature of many species and the unknown performance of the diagnostic tests employed. To overcome these issues, we used a combination of hierarchical models (site-occupancy and N-mixture models) applied to copro-parasitological data obtained from fecal samples assigned to the host species by molecular methods in the Iberian ibex in north-western Iberian Peninsula. The aims were to compare the performance of four diagnostic tests (Mini-FLOTAC, McMaster, Willis flotation, and natural sedimentation) and to use this methodological approach (molecular analysis with hierarchical models) to better estimate positivity proportion and shedding intensity in a wild ibex population. Pooled fecal samples were collected, and those confirmed by molecular analyses to be the host species in question were included in the study. Hierarchical models confirmed different performances of each diagnostic test, with Mini-FLOTAC showing higher sensitivity for eimeriid coccidia, Willis flotation (for proportion positive) and McMaster (for shedding intensity) in gastrointestinal Strongylida, and equal performance of MiniFlotac/Willis flotation (for proportion positive) and MiniFlotac/McMaster (for shedding intensity) in Moniezia spp. This study employed a combination of molecular and statistical methods that improved the estimates of prevalence and shedding intensity and allowed us to compare the performance of four diagnostic tests while assessing the effect of covariates. Such improvements are critical to enhancing inference in non-invasive wildlife copro-parasitological studies.

Pastoral Burning and Its Contribution to the Fire Regime of Alto Minho, Portugal

Alto Minho (in northwestern Iberia) is one of the European regions most affected by fires. Many of these fires originate from rangeland management of Atlantic heathlands, and, while being illegal, often are not actively suppressed. In this study, pastoral fires (autumn-to-spring fires unrecorded by authorities), spring wildfires, and summer wildfires were independently mapped and dated from remote sensing. Alto Minho burned at a mean annual rate of 5.0% of the territory between 2001 and 2020. Pastoral burning totalled 40,788 hectares during the period, accounting for 20% of the total burnt area. Rangeland burning occurs mostly from December to April, the rainiest months that guarantee the conditions for pasture renewal and fire self-extinction. The mean fire return interval of pastoral burning is slightly higher than that of wildfires (13 years vs. 11 years), except in part of the inner mountains where it dominates fire activity. Pastoral fires are more frequent and largely prevail over wildfires in the parishes with higher livestock quantities. Conversely, the largest wildfires and higher summer burnt areas correspond with very low livestock and nearly non-existing pastoral fires. Traditional fire knowledge should not be overlooked by fire management, as it contributes to more sustainable fire regimes and ecosystems.

Palaeoenvironmental Framing of the O Areal Roman Saltworks and Related Anthropogenic Activities in North-western Iberia

ABSTRACT The NW Iberian city of Vigo contains buried structures of a Roman salinae that follow the ancient coastline. To investigate its environmental legacy, we studied two pedo-sedimentary profiles at the O Areal saltworks to reconstruct human activities during and after the salinae use, as well as framing them within the last two millennia of climate variability. The bottom layer consists of organic-rich sands, with marine palynomorphs, confined within the saltworks’ structures that operated during the Early Roman Empire, when the demand in fish-salted products increased and the salting industry fluorished on the Atlantic coast of Iberia. During the Late Roman Empire, salt production at the O Areal may have ended, coeval with the development of a marsh with hydro-hygrophyte vegetation and the salting industry demise. The Roman environment also experienced intense agropastoralism that triggered water eutrophication. After Roman times, a dune phase sealed the archaeologicl structures. The overall trend points to a shift from a marine to a terrestrial setting coeval to known periods of climate variability. Therefore, humans and climate impacted the coast during the last two millennia, including the very intense Roman-period saltworks, agriculture and livestock. Roman times climate would have also influenced the saltworks’ establishment and abandonment.

Reassessing Roman military activity through an interdisciplinary approach: Myth and archaeology in Laboreiro Mountain (Northwestern Iberia)

The present work aims at the archaeological characterisation and historical contextualisation of two large enclosures recently located through remote sensing in the Laboreiro Mountain on the border between Portugal and Galicia: Lomba do Mouro and Chaira da Maza. Ancient written sources, remote sensing, archaeological survey, and absolute dating will be combined in order to shed new light on these enclosures.Given the specificity of the archaeological structures and contexts under study, the need to use complementary absolute dating methods will be discussed, including luminescence and radiocarbon dating. The results in the case of the Lomba do Mouro enclosure point to it possibly being a Roman military camp of late-Republican chronology.

Peasant proprietors, social mobility and risk aversion in the early Middle Ages: an Iberian case study

ABSTRACT This article investigates an important but neglected question concerning the social and economic dynamics of village communities in early medieval north-western Iberia: why did ‘medium owners’ – that is, peasants who accumulated significant landed holdings – assemble portfolios of property large enough to produce significant surpluses in an age in which the institutional infrastructure needed to marketise such surpluses was rudimentary? The pursuit of upward social mobility is most commonly posed as the answer to this question; but how exactly did medium owners stand to gain? After all, north-western Iberia in the early Middle Ages was a scarcely monetised society in which would-be medium owners could not expect to be paid in coin for the sale of their surplus and consequently see their options as buyers increase. Why, then, assume the risks involved in expanding one’s farming operation? Certainly, the acquisition of landed wealth brought with it clear advantages, including symbolic prestige and an expanded client network. Yet this article suggests that we can better understand why socially mobile peasants sought to own landed resources capable of producing significant surpluses only if we are prepared to re-examine important historiographical motifs, including peasant risk aversion, and the culturally constituted nature of the subsistence minimum.

Snowfall events in the Cantabrian Mountains of northwestern Spain: WRF multiphysics ensemble assessment based on ground and multi-satellite observations

Snowfall in elevated areas of the mid-latitudes has a strong impact on infrastructure, freshwater availability, and the climate system. The Cantabrian Mountains of the northwestern Iberian Peninsula are very vulnerable to climate change because of their moderate altitudes, which limits their snowfall. Monitoring snow events is essential for the evaluation of weather and climate prediction models. However, measurement networks are scarce in mountainous areas and have great uncertainties because of blizzards. In this study, a multiphysics ensemble of the Weather Research and Forecasting (WRF) model was designed using three microphysics and two planetary boundary layer (PBL) schemes to simulate nine snowfall events in the Cantabrian Mountains during autumn and winter 2021–2022. The WRF was validated using several snow characteristics, such as liquid water equivalent, snow cover, and snow depth. Liquid water equivalent was evaluated using snow-gauge networks and satellite products in an assessment of snow cover. In addition, a monitoring network of webcams and snow poles was implemented, improving the low density of snow observations in the mountains. The results showed good model performance for detection of snow cover and slight overestimation of liquid water equivalent and snow thickness, which may have been caused by under-catchment that is generally an effect of wind on the measurement systems and by snow compaction, respectively. Morrison microphysics and Mellor-Yamada-Nakanishi-Niino (MYNN PBL) yielded better results for liquid water equivalent at higher altitudes and output greater snow cover. The results help determine the best configurations for snow modelling in the study area to develop future studies of the spatiotemporal patterns of snow distribution.

Carbon and nitrogen stable isotope compositions provide new insights into the phenotypic plasticity of the invasive species Carpobrotus sp. pl. in different coastal habitats

The genus Carpobrotus N.E.Br. comprises several aggressive invasive species that threaten biodiversity in coastal areas worldwide. We studied the phenotypic plasticity of Carpobrotus sp. pl. invading four coastal habitats in the north-western Iberian Peninsula (coastal cliffs, disturbed areas, dunes and coastal forests). We measured morphological traits and carbon (δ13C) and nitrogen (δ15N) stable isotope compositions of Carpobrotus sp. pl. individuals collected in each habitat. Our results indicated that leaf carbon content (% C) and dry shoot weight were higher on cliffs and lower in mixed forests. In contrast, leaf hydration was higher in mixed forests and lower on cliffs. Leaf nitrogen content (% N) was higher in forests, which might be due to the presence of Acacia longifolia, an alien tree that accumulates N in the soil through symbiotic associations with N fixing bacteria. Differences in δ15N showed the use of different N sources in each habitat. Values were higher in disturbed areas with greater human activity and lower on cliffs and forests. δ13C was higher in cliffs and dunes, suggesting CAM activity where drought and salinity are more intense. Water use efficiency (iWUE) and δ13C were higher on cliffs and dunes, suggesting an adaptation and high tolerance of Carpobrotus sp. pl. to unfavourable conditions such as drought or salinity in the invaded areas.