Northeastern Iberian Peninsula Research Articles

Validation of a Meteosat Second Generation solar radiation dataset over the northeastern Iberian Peninsula

Abstract. Solar radiation plays a key role in the Earth's energy balance and is used as an essential input data in radiation-based evapotranspiration (ET) models. Accurate gridded solar radiation data at high spatial and temporal resolution are needed to retrieve ET over large domains. In this work we present an evaluation at hourly, daily and monthly time steps and regional scale (Catalonia, NE Iberian Peninsula) of a satellite-based solar radiation product developed by the Land Surface Analysis Satellite Application Facility (LSA SAF) using data from the Meteosat Second Generation (MSG) Spinning Enhanced Visible and Infrared Imager (SEVIRI). Product performance and accuracy were evaluated for datasets segmented into two terrain classes (flat and hilly areas) and two atmospheric conditions (clear and cloudy sky), as well as for the full dataset as a whole. Evaluation against measurements made with ground-based pyranometers yielded good results in flat areas with an averaged model RMSE of 65 W m−2 (19%), 34 W m−2 (9.7%) and 21 W m−2 (5.6%), for hourly, daily and monthly-averaged solar radiation and including clear and cloudy sky conditions and snow or ice cover. Hilly areas yielded intermediate results with an averaged model RMSE (root mean square error) of 89 W m−2 (27%), 48 W m−2 (14.5%) and 32 W m−2 (9.3%), for hourly, daily and monthly time steps, suggesting the need of further improvements (e.g., terrain corrections) required for retrieving localized variability in solar radiation in these areas. According to the literature, the LSA SAF solar radiation product appears to have sufficient accuracy to serve as a useful and operative input to evaporative flux retrieval models.

WeMO effects on the amount and the chemistry of winter precipitation in the north-eastern Iberian Peninsula

The cluster classification of provenances at a site in the NE Iberian Peninsula indicated that in the period of extended winter (December to March, DJFM) fast Atlantic air flows correspond to positive WeMO index (WeMOi), while negative WeMOi are associated to Mediterranean circulations. The amount of winter precipitation was inversely correlated with winter WeMOi. Wet deposition fluxes of marine-derived (Na + , Mg 2+ and Cl ) and anthropogenic-derived (NO3 and K + ) ions were significantly (and negatively) related to winter WeMOi. The negative phase of WeMO causes the entry of air masses from the Mediterranean into the Iberian Peninsula, that are enriched with marine ions. For NO3 this result suggests the advection over the Mediterranean of polluted air masses from southern Europe and the scavenging and deposition of this pollution by rain during WeMO negative phases. This will carry long-range pollutants to the NE Iberian Peninsula, but local pollutants may also contribute, as precipitation events from the Mediterranean (associated to negative WeMOi) may incorporate local anthropogenic emissions that build up during the winter anticyclonic episodes typical of the region.

El complex <i>Euphorbia esula-E. virgata</i> (Euphorbiaceae) al nord-est de la península Ibèrica: precisions corològiques, ecològiques i taxonòmiques

The recent discovery in the north-east of the Iberian Peninsula (southern and central Catalonia) of three populations belonging to the Euphorbia esula–E. virgata complex (Euphorbiaceae) prompted us to conduct a macro- and micromorphological study to ascertain their taxonomic identity. Only two previous records of plants from this complex existed in the area and these were gathered in 1908/1909 (previously identified as E. esula subsp. saratoi ) and in 1930 ( E. esula s. l. ). Our results indicate that all the material examined (both recent and old samples) can be attributed to E. virgata , a taxon whose main distribution area lies in eastern Europe, and whose southwestern distribution limit lies in northeastern Iberian Peninsula. The macromorphological characteristics vary somewhat between populations and some individual plants bear a strong resemblance to forms that are usually referred to E. ×pseudovirgata , a supposed hybrid of E. virgata and E. esula . It is not possible, however, to confirm the presence of this hybrid in the region without further studies. After this study, E. esula subsp. esula should be excluded from Catalonia, Valencia and Aragon. The present-day populations we attribute to E. virgata are highly localized but dense. They are found in herbaceous habitats with clear anthropic influence (abandoned fields and the edges of roads and tracks), on deep, fairly dry soils. These habitats are similar to those typical of E. virgata in eastern and central Europe. It is likely that the populations are temporal and indeed in two of the three recent localities it has been confirmed that they date from after 2005. Current data suggest that this is a non-indigenous species, but in view of the fact that it was detected a century ago, the possibility that it is a rare indigenous species with itinerant populations cannot be ruled out.

Environment and climate during MIS 7 and their implications for the late Middle Pleistocene hominins: The contribution of Mollet cave, Serinyà, Girona, northeastern Iberian Peninsula

Marine Isotope Stage 7 (MIS 7) is an interglacial that has not been a major topic of scientific interest, yet is interesting because it contains five warm and cold phases (MIS 7e-a) within a brief period of time (ca. 246–186 ka). In this context, there are several sites that contain Middle Pleistocene human remains in Europe, including Mollet cave, the subject of this study. Analyses of the small vertebrates from this cave, together with the numerical dating (ca. 215 ka), established the environmental and climatic conditions in which the hominins who frequented the cave lived. The results obtained situate the Middle Pleistocene hominins of Mollet cave in the MIS 7c substage, indicating that the occupation by humans took place in a transitional phase from a warm to a cold stage with forest development.

The European Lepidocyrtus lanuginosus group (Collembola: Entomobryidae), definition and description of a new species from Spain

The Lepidocyrtus lanuginosus group is formed by the species L. lanuginosus and L. cyaneus, which can be differentiated by the body color pattern. In the present paper several populations of these two species from the Northeastern Iberian Peninsula have been studied. This study has allowed the detection of chaetotaxic and morphological differences distinguishing the two mentioned species. Also the description of the new species L. bicoloris has been made (also characterized by the body color pattern), as well as a redefinition of the European Lepidocyrtus lanuginosus group.

Nocturnal offshore precipitation near the Mediterranean coast of the Iberian Peninsula

While nocturnal offshore precipitation, which produces rain cells and bands, has been studied in tropical areas, few studies have analyzed the occurrence of this phenomenon at higher latitudes. Using radar reflectivity, nocturnal rainfall in the western Mediterranean area has been detected near the coast of the Iberian Peninsula and North Africa. More than 50 events have been recorded since 2009. MM5 mesoscale simulations of some of the recorded events allow us to establish that the most likely causes for these precipitation events are: (1) the interaction between cold air masses conducted by drainage and katabatic winds, and (2) a wetter and warmer synoptic wind. Two different episodes are presented: one in the northeastern Iberian Peninsula, caused by stratiform clouds, which occurred at the mouths of three rivers; the other case, produced by convective clouds, occurred at the southern Iberian Peninsula and was caused by the drainage winds flowing down from some mountain ranges located close to the coast.

Factors affecting the establishment of the invasive crayfish Procambarus clarkii (Crustacea, Decapoda) in the Mediterranean rivers of the northeastern Iberian Peninsula

It is essential to find the combination of factors associated with ecosystem invasibility, as this forms part of basic knowledge on biological invasions and provides important information to guide management and conservation decisions. We surveyed 325 sampling sites in Catalonia to investigate relationships between crayfish presence and a series of biotic and abiotic factors, including fish abundance and species richness, geographical features, and water mineralization and eutrophication. Abiotic data provided by 29 environmental variables were studied by principal-components analysis. We then used a combination of three statistical approaches (comparison of average scores, general linear mixed models, and hierarchical partitioning analysis) to determine the potential relationship between crayfish occurrence and predictors. Our findings seem to indicate that the presence of crayfish was associated with geographical features, water mineralization and eutrophication, and the introduction of non-indigenous fish species to Catalonia. Our results also suggest that re-establishment of the natural hydrology of Mediterranean streams could hinder the spread of Procambarus clarkii. This, combined with preservation of headwater streams and attempts at local extirpation of P. clarkii, would favour native species and, potentially, enable the successful reintroduction of the native white-clawed crayfish (Austropotamobius pallipes species complex).

Chemical characterization of Lavandula latifolia Medik. essential oil from Spanish wild populations

A survey of Lavandula latifolia Medik. wild populations was carried out covering the distribution area of the species in Spain. Samples (194) from 6 different biogeographic provinces were gathered, dried, hydrodistilled and their essential oils analyzed by gas chromatography (GC). Forty compounds were identified, three of them (1,8-cineole, linalool and camphor) accounting for more than 70% of the total oil in all the analyzed samples. Linalool and camphor were inversely correlated. Camphor production seemed to be helped by lower altitudes. Two-step clustering analysis was conducted and samples were classified into three different clusters: C1 characterized by its high content in camphor, borneol, camphene, α- and β-pinene; C2 characterized by its high content in linalool and terpinen-4-ol and C3 characterized by the presence of limonene, transcaryophyllene and/or β-phellandrene, compounds that did not appear in significant percentages in the other two groups. C1 populations are the most frequent in samples from Eastern and North-Eastern Iberian Peninsula (Balearic-Catalonian-Provençal and Cévenno-Pyrenean biogeographic provinces). Populations from Central Iberian Peninsula (Mediterranean Central and West Iberian biogeographic provinces) and upland areas from the South of Spain (Betican and Murcian-Almerian biogeographic provinces) were mainly grouped in C2. C3 samples were also found in Cévenno-Pyrenean province and, to a lesser extent, in the Central provinces (Mediterranean Central and West Iberian). This distribution showed certain relationship between the chemical composition of the essential oils and their geographical origin.

The First Neolithic Communities in Northeast Iberia: Procurement, Production, and Use of Lithic Tools at the Settlement of Caserna de Sant Pau Del Camp (Barcelona, Spain)

ABSTRACT Caserna de Sant Pau del Camp is one of the earliest Neolithic settlements in Northeast Iberia and represents the occupation of coastal areas by the first farming communities in the region. It is located in the city center of Barcelona and displays a continuous Early Neolithic occupational sequence from Cardial to Postcardial Neolithic during nearly a thousand years. It also includes what currently is the earliest Neolithic necropolis known in northeastern Iberia, dated to the late fifth millennium cal BC (Postcardial). This article presents a detailed study of the chipped stone assemblage. The results have enabled the characterization of a series of aspects concerning lithic production such as raw material procurement strategies, technology, and lithic use patterns over a time-span of almost a thousand years, which trace interesting parallels and differences with other parts of the Iberian Peninsula and France. Second, the integration of these results with previous data from Sant Pau and a regional contextualization have brought to light a series of key aspects concerning the role played by coastal communities in the Neolithization process of the Northeastern Iberian Peninsula, coastal landscape exploitation, mobility (maritime?) patterns, exchange networks, and a host of other issues.

Relationship between wind power production and North Atlantic atmospheric circulation over the northeastern Iberian Peninsula

The wind power generated during winter months 1999–2003 at several wind farms in the northeastern Iberian Peninsula is investigated through the application of a statistical downscaling. This allows for an improved understanding of the wind power variability and its relationship to the large scale atmospheric circulation. It is found that 97 % of the variability of this non-climatic variable is connected to changes in the atmospheric circulation. The methodological uncertainty associated with multiple configurations of the statistical downscaling method replicates well the observed variability of the wind power, an indication of the robustness of the methodology to changes in the model set up. In addition, the use of the statistical model is extended out of the observational period providing an estimation of the long-term variability of wind power throughout the twentieth century. The extended wind power reconstruction shows large inter-annual and multidecadal variability. Alternative approaches to calibrate the empirical downscaling model using actual wind power observations have also been investigated. They involve the estimation of wind power changes from downscaled wind values and make use of several transfer functions based on the linearity between wind and wind energy. The performance of the latter approaches is similar to the direct downscaling of wind power and may allow wind power production estimations even in the absence of historical wind turbine records. These results can be of great interest for deriving medium/long term impact-oriented energy assessments, especially when wind power observations are missing as well as in the context of climate change scenarios.

Changes in the vegetation and human management of forest resources in mountain ecosystems at the beginning of MIS 1 (14.7–8 ka cal BP) in Balma Guilanyà (Southeastern Pre-Pyrenees, Spain)

The site of Balma Guilanyà (southeastern Spain) records an extensive human occupation during the beginning of MIS 1, based on a variety of archaeobotanical indicators, although its sequence contains gaps in the record of human occupation. The study of different archaeological proxies recovered from its sequence, especially charcoal, seeds and fruits, allows analysis of the ecological changes that occurred at the southern flanks of the Pyrenees from the Bølling/Allerød amelioration to the Boreal. The analyses also illuminate the strategies developed by hunter-gatherers of the northeastern Iberian Peninsula, and especially of the changes in firewood used at this site over a long time (over 5000 years), which indirectly provide information about the transformation of the plant communities of mountain ecosystems. In parallel, a growing interest in re-collecting wild fruits can be perceived. The results suggest that this activity was widely in use during the early Holocene, although it may go back to the Allerød. These results suggest that despite the limitations of the archaeobotanical record of Balma Guilanyà, we can recognize different patterns in the management of plant resources by the hunter-gatherers that intermittently visited this site.

Are protected areas truly protected? The impact of road traffic on vertebrate fauna

The extension of road networks is considered one of the major factors affecting fauna survival. Roadkill has been documented widely and affects all taxonomic groups. Although roadkill is associated mainly with traffic density, some life-history traits of species and the area surrounding roads are expected to modify number of roadkills both taxonomically and geographically. Here we studied the number of roadkills of vertebrates in an extensive region in the northeastern Iberian Peninsula. We surveyed 820 km of 41 roads in two different seasons (spring and autumn), that differ in traffic intensity. In addition, we covered zones with distinct climatic characteristics and levels of protection of the surrounding habitats. Amphibians showed the highest number of roadkills whereas reptiles, birds and mammals had similar rates. General Linear Model tests showed no differences in roadkills by climatic region; however, differences in number of roadkills were linked to protection status, with the highest number of casualties in highly protected areas. Redundancy Analysis demonstrated that the number of amphibians and reptiles killed was associated with roads in highly protected areas whereas that of mammals and birds was linked to unprotected areas. Protected areas often receive many visitors, which in turn may increase wildlife casualties as a result of greater traffic density. We recommend that correction measures be taken to reduce the high number of vertebrate fauna killed along roads that cross protected areas.

Impact of climate variability on summer fires in a Mediterranean environment (northeastern Iberian Peninsula)

We analyse the impact of climate interannual variability on summer forest fires in Catalonia (northeastern Iberian Peninsula). The study period covers 25 years, from 1983 to 2007. During this period more than 16000 fire events were recorded and the total burned area was more than 240 kha, i.e. around 7.5% of whole Catalonia. We show that the interannual variability of summer fires is significantly correlated with summer precipitation and summer maximum temperature. In addition, fires are significantly related to antecedent climate conditions, showing positive correlation with lagged precipitation and negative correlation with lagged temperatures, both with a time lag of two years, and negative correlation with the minimum temperature in the spring of the same year. The interaction between antecedent climate conditions and fire variability highlights the importance of climate not only in regulating fuel flammability, but also fuel structure. On the basis of these results, we discuss a simple regression model that explains up to 76% of the variance of the Burned Area and up to 91% of the variance of the number of fires. This simple regression model produces reliable out-of-sample predictions of the impact of climate variability on summer forest fires and it could be used to estimate fire response to different climate change scenarios, assuming that climate-vegetation-humans-fire interactions will not change significantly.

Lake Banyoles (northeastern Spain): A Last Glacial to Holocene multi-proxy study with regard to environmental variability and human occupation

Analyses of a 67-m long sediment core from Lake Banyoles (northeastern Spain) have revealed evidence for the palaeoclimate history of the northern Iberian Peninsula. Investigations have included high-resolution and non-destructive sediment-physical, geochemical, and optical methods to generate proxies indicative of sedimentologic variability and climate change. Primary stratigraphic control is based on 14C and U-series dates of organic and inorganic material, as well as tephra from the Late Pleistocene Olot volcanic episode.While preliminary ages obtained for the core base date back to approximately 60 ka, the Last Glacial Maximum (23–19 ka) interval ends at 15 m. The top 8 m of deposits accumulated in the Holocene. Several slump events were observed in the core section, as were microtectonic structures, which constrain the movement. Evidence for palaeoclimate variations in element ratios is interpreted to represent effects of Heinrich Events H0–H5. Associated changes in environmental conditions (e.g., humidity) may have affected human occupation during the Palaeolithic–Neolithic period. Implications on human occupation in northeastern Iberia due to climate changes are discussed from archeological findings and cave sediments in neighboring areas and are analyzed with respect to the palaeolimnologic data of Lake Banyoles.

A multidisciplinary approach to reconstructing the chronology and environment of southwestern European Neanderthals: the contribution of Teixoneres cave (Moià, Barcelona, Spain)

According to pollen analysis and the 18O-isotope curve, the first part of the Late Pleistocene (ca 128–30 ka) is mainly characterized by a dynamic that alternates cold phases (Heinrich Events) and temperate phases (interstadials). These rapid fluctuations provide the context for the Neanderthal occupations in the northeastern part of the Iberian Peninsula. In this paper we present the chronological, environmental and climatic data obtained by analyzing the pollen, the charcoal, the small vertebrates (amphibians, squamates and small mammals) and the large-mammal dental wear at the Neanderthal site of Teixoneres cave, Northeastern Iberia. Levels II and III from this cavity have provided Mousterian industries and other evidence of Neanderthal occupations, such as cut-marks in large-mammal bones. A multiproxy study such as this constitutes a new approach to the chronological, environmental and climatic context in which Neanderthal populations lived in southwestern Europe (Iberian Peninsula). The results allow us to establish a relative chronology for these two levels of between ca 30–90 ka and show that they are associated with different environmental and climatic conditions: temperate and humid for Level III and cold and dry for Level II. This demonstrates that the Neanderthals were well adapted to the territory that they occupied, irrespective of the climatic conditions.

La arquitectura religiosa hispánica del siglo IV al X y el proyecto del Corpus Architecturae Religiosae Europeae - CARE-Hispania

This contribution summarizes the objectives and the tasks developed within the framework of the CARE-Hispania project; it provides also some general thoughts about religious architecture in the Iberian Peninsula and the Balearics. The main problems concerning its study are addressed: the long historiographic tradition, and the possibilities offered by the buildings themselves, the liturgy, the documents and the epigraphic evidence in order to study the architecture. The paper focuses in the northeastern Iberian Peninsula and the Balearics due to the fact that the project has initiated its activities in these regions.

Altitudinal species richness patterns of vascular plants in the south-eastern Pyrenees and nearby mountains of Catalonia

Background: Studying how species richness varies with altitude has become an important part of investigations on mechanisms explaining regional-scale plant species diversity. Altitudinal diversity patterns are poorly known in the Pyrenees and elsewhere in the main mountain massifs in Catalonia (north-eastern Iberian Peninsula). Aim: We examine the altitudinal patterns of species richness in the Catalan Pyrenees and compare them with those in other mountains in Catalonia. Altitude patterns of species richness in the Pyrenees are compared for functional and taxonomic groups of vascular plants. Methods: Data on vascular plants were obtained from the Biodiversity Data Bank of Catalonia. We used rarefaction and interpolation to quantify the altitudinal diversity patterns. Results: The interpolated and rarefied richness generally peaked in the lower part of the altitudinal gradient, but with remarkable variation depending on the taxonomic or functional groups considered. Using all species, there was little variation between the different mountains, but the altitude at which richness started to decrease varied between them. Conclusions: The pronounced differences among different taxonomic groups and life-forms indicate a strong phylogenetic and adaptive signal on the altitudinal diversity pattern in the Catalan Pyrenees. The lack of regional differences within Catalonia is probably due to small differences in the intensity of climatic gradients across mountains.

Vegetation dynamics and anthropogenically forced changes in the Estanilles peat bog (southern Pyrenees) during the last seven millennia

Estanilles peat bog, located in the northeastern Iberian peninsula, was studied to determine the anthropogenic changes in the landscape over the past seven millennia. The pollen diagram and sedimentary charcoal analyses from this site permit us to reconstruct the landscape changes in an area of both Mediterranean and Atlantic influence. In addition, Montarenyo ombrotrophic peat bog was studied to strengthen the analysis of data from more recent centuries. This paper attempts a reconstruction of historical cultural landscapes using two complementary palaeobotanical proxies (pollen and charcoal) in high mountain environments. The macroscopic charcoal record shows a fire signal since 7500 cal. b.p. However, the relationship between fire frequency and human impact is not always linear. This divergence is linked to fuel availability and fire activity. Fire has been used repeatedly to clear ground and to maintain open areas, and has been a key tool for the management of these high mountain areas. The intensity of use of the landscape implies the expansion of agricultural areas into higher altitudes, including cereal cultivation above 2,200 m a.s.l., during the Middle Ages. The first clear human influence detected in the pollen percentage data is recorded between 6000 and 7000 cal. b.p. and, until present times, the greatest changes in vegetation and landscape history occurred during periods of particular specialization in socioeconomic activities during the Middle Ages.

The siliciclastic Permian-Triassic deposits in Central and Northeastern Iberian Peninsula (Iberian, Ebro and Catalan Basins): a proposal for correlation

The siliciclastic deposits of the Iberian, Ebro and Catalan Basins have been described for more than a century, but facies similarities and a lack of biostratigaphic data have difficulted the correlation of the local stratigraphic units in a general framework up to now. Combining pollen and spores data, the identification of the regional unconformities and hiatuses and the quantitative analysis of the subsidence by backstripping methods, a new correlation scheme for these facies is proposed.

Man-made Mediterranean temporary ponds as a tool for amphibian conservation

Mediterranean temporary ponds (MTPs) are crucial breeding sites for local amphibians, a faunal group in decline in the Mediterranean mainly due to wetland destruction. Although the disappearance of len- tic habitats in other regions of the world has been ameliorated by the creation and restoration of wetlands, these tactics remain untested in Mediterranean wetlands. To evaluate the amphibian colonization dynamics of artificial MTPs in the north-eastern Iberian Peninsula, we monitored two artificial MTPs (one in a high- diversity area and the other in a low-diversity area) over 2 years. We selected reference wetlands at each area, and amphibian communities of man-made MTPs were compared to those of reference wetlands. We found that, beginning in the first year, artificial MTPs were a valuable habitat for regional amphibian fauna. Posteriorly, we focused on the reproductive success of the natterjack toad, Bufo calamita. Using a drift fence equipped with pit-fall traps, we measured the abundance of both reproductive adults entering the pond and post-metamorphic individuals exiting the pond. Using mark-recapture methods, we analyzed the time and energy costs associated with reproduction in the artificial MTPs. We observed a highly variable colonization dynamics between sites, between hydroperiods, and within hydroperiods, and these dynamics often depended on meteorological factors. Our results suggest that even at a short timescale, native amphibian species such as B. calamita can benefit from wetland creation in the Mediterranean region.