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Central Spain (central + spain)
Selected AbstractsROCK ART AND RITUAL LANDSCAPE IN CENTRAL SPAIN: THE ROCK CARVINGS OF LA HINOJOSA (CUENCA)OXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2003MARGARITA DÍAZ-ANDREU Summary. In this article the rock art carvings of La Hinojosa in central Spain are examined. Their connection to a major transit route recorded at least from the medieval period is explored, as well as their location in a valley located at the confluence of two primary river basins in the Iberian Peninsula separated by less than five kilometres. It is argued that this singularity of the landscape seems to have been perceived by the people who marked the stones. From the 17 decorated rocks recorded in La Hinojosa valley, three were exceptionally elaborately decorated. They were situated at regular intervals in the valley. The site with the greatest number of motifs, the large rock of San Bernardino, occupies a central location. This site is also exceptional because of the transformations which the rock shows throughout the day, pointing to a narrative in which cups and anthropomorphs seem to have a primary role. It is suggested that gender may have constituted one of the main guidelines of the narrative, given the apparent replacement of feminine by masculine human representations throughout the day. [source] Regional and local influence of grazing activity on the diversity of a semi-arid dung beetle communityDIVERSITY AND DISTRIBUTIONS, Issue 1 2006Jorge M. Lobo ABSTRACT This study analyses the effect of resource availability (i.e. sheep dung) on dung beetle communities in an arid region of Central Spain, both at regional and at local scales. A total of 18 sites within 600 km2 were sampled for the regional analysis and 16 sites within the 30 km2 of an Iberian municipality were sampled for the local analysis. Spatial and environmental characteristics of sampling sites were also compiled at both scales, including measures of grazing activity (livestock density at regional scale, and two counts of rabbit and sheep dung at local scale). At a regional scale, any environmental or spatial variable can help to explain the variation in abundance. However, species richness was related to summer precipitation and composition was related to elevation. At local scale, abundance is not significantly related to any of the environmental variables, but species richness was related to the local amount of sheep dung (27% of variance). The amount of dung in a 2-km buffer around the site accounts for 27,32% of variance in abundance and 60,65% of variance in species richness. The presence of the flock with the highest sheep density explains 53% of abundance variability and 73% of species richness variance. A cluster analysis of localities identified two main groups, one characterized by a lower abundance and species richness that can be considered a nested subsample of the species-rich group. The mean and maximum amount of sheep dung in the sites separated by less than 2 km are the only significant explanatory variables able to discriminate both groups. These results suggest that grazing intensity (and the associated increase in the amount of trophic resources) is a key factor in determining local variation in the diversity and composition of dung beetle assemblages. However, dung beetle assemblages are not spatially independent at the analysed resolution, and the amount of dung in the surroundings seems to be more important for locally collected species than the dung effectively found in the site. Although differences in the availability and quantity of trophic resources among nearby sites could be affecting the population dynamics and dispersion of dung beetles within a locality, sites with larger populations, and greater species numbers would not be able to exercise enough influence as to bring about a complete local faunistic homogenization. [source] Double-nesting behaviour and sexual differences in breeding success in wild Red-legged Partridges Alectoris rufaIBIS, Issue 4 2009FABIÁN CASAS Double-nesting behaviour, a rare breeding system in which females lay in two nests, one incubated by herself and the other one by her mate, could be considered an intermediate stage in the evolutionary trend from biparental to uniparental care of single clutches. We examined the occurrence and success of double-nesting behaviour in Red-legged Partridges Alectoris rufa in Central Spain. Clutch size and hatching success were recorded, as well as the variation in these between years and between incubating sexes. Participation in incubation was higher for females (94.76%) than males (41.0%), and the proportion of incubating males varied markedly between years, with no incubating males in one dry year and approximately 50% of males incubating in other years. There was significant variation among years and between sexes in laying date, clutch size and hatching success. Clutch size decreased with later laying date in males and females. The probability of clutch loss to predation differed between sexes, being much higher for nests incubated by females. Our results suggest that both rainfall and predation influence the occurrence and success of double-nesting. [source] Determining the effects of habitat management and climate on the population trends of a declining steppe birdIBIS, Issue 3 2009MARÍA PAULA DELGADO The Little Bustard Tetrax tetrax is one of the most threatened steppe bird species in Europe, due mainly to agricultural intensification. Despite the relative importance of the Iberian population (approximately 50% of the global population) little is known about its dynamics and trends, especially in core distribution areas. This study evaluates the influences of meteorological factors and land management on the oscillations and medium-term trends of two Little Bustard populations in Central Spain. During 2001,2007, surveys of breeding male and female Little Bustards were carried out in two central Spanish locations: Valdetorres, in Special Protection Area (SPA) no. 139 (1600 ha), and Campo Real, in Important Bird Area (IBA) no. 075 (1150 ha). Densities were 3.3,4.0 and 1.1,2.1 males/km2 in Campo Real, and 1.8,2.2 and 0.6,1.3 females/km2 in Valdetorres. The sex ratio was biased towards males in both cases. Both populations declined during 2001,2007, especially in Valdetorres (60%). Variation in habitat composition did not explain variation in the numbers of males. Both populations were influenced by total precipitation in the preceding October,May period. Results suggest that the Little Bustard may be sensitive to future climate trends in Europe. Finally, different simulated demographic scenarios suggest that low female survival and productivity may be the immediate cause of the decline in Little Bustard populations, which is consistent with their sensitivity to climatic conditions. [source] Daytime variation in T-cell-mediated immunity of Eurasian kestrel Falco tinnunculus nestlingsJOURNAL OF AVIAN BIOLOGY, Issue 5 2006Jesús Martínez-PadillaArticle first published online: 15 AUG 200 Host-parasite interactions are central in evolutionary and behavioural ecology. In the last few years, skin injections of the mitogen Phytohaemagglutinin (PHA) have become one of the most important and widely used in-vivo assays of immune function in birds. However, there are no studies of the circadian variation suggesting that care should be taken interpreting results when using this technique. This 3-year study assessed PHA responses as a function of daylight time in 310 Eurasian kestrel Falco tinnunculus nestlings at 24 days of age in Central Spain. I found that T-cell-mediated immunity was positively related to nestling mass and varied among years. Controlling for these variables, I also found that T-cell-mediated immunity decreased with the hour of sampling, and that this pattern was consistent between years. In addition, I found that at the end of the day only, T-cell-mediated immunity decreased with brood size. Parasites seem not to be behind this pattern, but I suggest that the cumulative effect of sibling competition during the day might explain the decrease of cellular immunity with the hour of sampling. Thus, I strongly recommend that future studies of cellular immunity should control for this potential source of variation when nestling self-maintenance is evaluated by the PHA-induced skin-swelling response. [source] The fate of seeds in Mediterranean soil seed banks in relation to their traitsJOURNAL OF VEGETATION SCIENCE, Issue 1 2006Juan Traba Abstract Question: Is there any change in seed density and species richness in Mediterranean surface soil banks during summer? Are there any relationships between these summer variations and seed traits (weight, length and shape), without and with controlling the phylogenetic effect? Location: Central Spain. Methods: Samples of the surface soil seed bank were collected in two Mediterranean systems, grassland and scrubland, at two points in the year: immediately after the summer production peak and immediately prior to the autumn germination peak. We used Canonical Correspondence Analysis ordination to check for changes in floristic composition and ANOVAs to check for changes in seed density and species richness between summer and autumn samples. We used multiple regression analysis to analyse the relationship between summer variations in soil seed density and form traits, with and without controlling phylogenetic relations. Results: Soil seed density dropped significantly during the summer in the two systems (28% in grasslands, repeated measures ANOVA test; F = 58.19, P < 0.01; 72% in scrublands, repeated measures ANOVA test; F = 75.67, P < 0.001). Species richness, however, only dropped significantly in the scrubland (32%; repeated measures ANOVA test; F = 9.17, P < 0.05). Variation in the floristic composition of the shallow banks was only significant in the scrubland. Changes in shallow bank density were related significantly to seed morphology features, with greater drops in species with heavier seeds in grasslands and species with longer seeds in scrubland. Conclusions: Our results show a substantial loss of seeds in the uppermost soil layer during the summer period between the point of peak production and the autumn germination peak. This drop was clearer in the scrubland than in the grassland. Longer and/or heavier seeds underwent the greatest declines in density at the end of summer, indicating a more intense effect of post-dispersal predation on large-seeded species. [source] Trends in the consumption of antidepressants in Castilla y León (Spain).PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 9 2010Association between suicide rates, antidepressant drug consumption Abstract Objective To learn the evolution of antidepressant and lithium use in Castilla y León (Central Spain) and its relationship with suicide rates. Methods A search in the ECOM (Especialidades Consumo de Medicamentos) database of the Spanish Ministry of Health for antidepressants and lithium was carried out for the period 1992,2005. Defined daily doses (DDD) per 1000 inhabitants per day were obtained as consumption data. Population and suicide rates data come from the Spanish National Statistics Institute. Results Antidepressant consumption increased 7-fold, from 6.9 DDD per 1000 inhabitants per day in 1992 to 47.3 in 2005; the corresponding increase in cost was more than 10-fold. Selective serotonin reuptake inhibitors (SSRIs) comprised 77% of the total consumption. Venlafaxine consumption multiplied by 2.2. The consumption of monoamine oxidase inhibitors (MAOIs) decreased after venlafaxine and mirtazapine were marketed. Lithium consumption increased by 76% during the period studied, but it plateaued in 2000. Conclusions The consumption of antidepressants in Castilla y León has increased remarkably and the pattern has changed; there is an increase in the consumption of the new and more expensive antidepressants such as venlafaxine and escitalopram. No association was observed between suicide rates and antidepressant consumption. Copyright © 2010 John Wiley & Sons, Ltd. [source] Predicted impact of climate change on threatened terrestrial vertebrates in central Spain highlights differences between endotherms and ectothermsANIMAL CONSERVATION, Issue 4 2010P. Aragón Abstract Climate change can induce shifts in species ranges. Of special interest are range shifts in regions with a conflict of interest between land use and the conservation of threatened species. Here we focus on the 94 threatened terrestrial vertebrates occurring in the Madrid region (Central Spain) and model their distributions using data for the whole peninsular Spain to evaluate which vertebrate groups are likely to be more sensitive to climatic change. First, we generated predictive models to quantify the extent to which species distributions are explained by current climate. We then extrapolated the models temporally to predict the effects of two climate-change scenarios on species distributions. We also examined the impact on a recently proposed reserve relative to other interconnected zones with lower protection status but categorized as Areas of Community Importance by the European Union. The variation explained by climatic predictors was greater in ectotherms. The change in species composition differed between the proposed reserve and the other protected areas. Endothermic and ectothermic vertebrates had different patterns of changes in species composition but those of ectotherms matched with temperature departures predicted by climate change. Our results, together with the limited dispersal capacity of herptiles, suggest that trade-offs between different design criteria accounting for animal group differences are necessary for reserve selection. [source] Effects of forest management on epiphytic lichen diversity in Mediterranean forestsAPPLIED VEGETATION SCIENCE, Issue 2 2010Gregorio Aragón Abstract Question: What are the responses of epiphytic lichens to the intensity of management along a large environmental gradient in Mediterranean Quercus forests? Location: Central Spain. Methods: This study was carried out on 4590 trees located in 306 forest stands dominated by Quercus faginea or Quercus ilex ssp. ballota. The effect of forest management and other predictor variables on several species diversity indicators were studied. Variables modelled were total species richness, cyanolichen richness and community composition. A large number of predictor variables were included: forest fragmentation (patch size, stand variability), climate and topographic (altitude, slope, sun radiation, annual rainfall and mean annual temperature) and intensity of management. General linear models and constrained ordination techniques were used to model community traits and species composition, respectively. Results: Total richness and especially cyanolichens richness were significantly and negatively affected by the intensity of management. Lichen composition was influenced by management intensity, climatic and topographic variables and stand variability. Conclusions: In Mediterranean forests, human activities related to forestry, agricultural and livestock use cause impoverishment of lichen communities, including the local disappearance of the most demanding species. The conservation of unmanaged forests with a dense canopy is crucial for lichen diversity. [source] Effect of abiotic factors on reproduction in the centre and periphery of breeding ranges: a comparative analysis in sympatric harriersECOGRAPHY, Issue 4 2001J. T. García Variables such as weather or other abiotic factors should have a higher influence on demographic rates in border areas than in central areas, given that climatic adaptation might be important in determining range borders. Similarly, for a given area, the relationship between weather and reproduction should be dissimilar for species which are in the centre of their breeding range and those that are near the edge. We tested this hypothesis on two sympatric ground-nesting raptors, the hen harrier Circus cyaneus and the Montagu's harrier Circus pygargus in Madrid, central Spain, where the hen harrier is at the southern edge of its breeding range in the western Palearctic and the Montagu's harrier is central in its distribution. We examined the reproductive success of both species during an 8-yr period, and looked at the influence of the most stressful abiotic factors in the study area (between-year variation in rainfall and within-year variation in temperature) on reproductive parameters. In the hen harrier, low levels of rainfall during the breeding season had a negative influence on annual fledging success and thus on population fledgling production. The relationship between rainfall and reproduction was probably mediated through food abundance, which in Mediterranean habitat depends directly on rainfall levels. In the Montagu's harrier, no negative effect of dry seasons on productivity was found. Additionally, in the hen harrier, the proportion of eggs that did not hatch in each clutch increased with higher temperatures during the incubation period. No such relationship was found in the Montagu's harrier. We interpret these between-species differences in terms of differences of breeding range and adaptations to the average conditions existing there. Hen harriers, commonest at northern latitudes, are probably best adapted to the most typical conditions at those latitudes, and have probably not developed thermoregulatory or behavioural mechanisms to cope with drought and high temperatures in Mediterranean habitats, in contrast to Montagu's harrier. Thus hen harrier distribution might be constrained by these variables, due to lower reproductive success or higher reproductive costs. Accordingly, a logistic regression analysis of the presence or absence of both species in 289 random points throughout the western Palearctic showed that the distribution of both species was related to temperature, but the relationship was in opposite directions for the two species: hen harriers had lower probability of breeding in areas with higher temperature (as expected in a species with a more northerly distribution). [source] Effects of temperature and elevation on habitat use by a rare mountain butterfly: implications for species responses to climate changeECOLOGICAL ENTOMOLOGY, Issue 4 2009SARAH ASHTON Abstract 1.,The present study used the mountain specialist butterfly Parnassius apollo as a model system to investigate how climate change may alter habitat requirements for species at their warm range margins. 2.,Larval habitat use was recorded in six P. apollo populations over a 700 m elevation gradient in the Sierra de Guadarrama (central Spain). Larvae used four potential host species (Sedum spp.) growing in open areas amongst shrubs. 3.,Parnassius apollo host-plant and habitat use changed as elevation increased: the primary host shifted from Sedum amplexicaule to Sedum brevifolium, and larvae selected more open microhabitats (increased bare ground and dead vegetation, reduced vegetation height and shrub cover), suggesting that hotter microhabitats are used in cooler environments. 4.,Larval microhabitat selection was significantly related to ambient temperature. At temperatures lower than 27 °C, larvae occupied open microhabitats that were warmer than ambient temperature, versus more shaded microhabitats that were cooler than ambient conditions when temperature was higher than 27 °C. 5.,Elevational changes in phenology influenced the temperatures experienced by larvae, and could affect local host-plant favourability. 6.,Habitat heterogeneity appears to play an important role in P. apollo larval thermoregulation, and may become increasingly important in buffering populations of this and other insect species against climatic variation. [source] Changes to the elevational limits and extent of species ranges associated with climate changeECOLOGY LETTERS, Issue 11 2005Robert J. Wilson Abstract The first expected symptoms of a climate change-generated biodiversity crisis are range contractions and extinctions at lower elevational and latitudinal limits to species distributions. However, whilst range expansions at high elevations and latitudes have been widely documented, there has been surprisingly little evidence for contractions at warm margins. We show that lower elevational limits for 16 butterfly species in central Spain have risen on average by 212 m (± SE 60) in 30 years, accompanying a 1.3 °C rise (equivalent to c. 225 m) in mean annual temperature. These elevational shifts signify an average reduction in habitable area by one-third, with losses of 50,80% projected for the coming century, given maintenance of the species thermal associations. The results suggest that many species have already suffered climate-mediated habitat losses that may threaten their long-term chances of survival. [source] Reproductive traits of stream-dwelling brown trout Salmo trutta in contrasting neighbouring rivers of central SpainFRESHWATER BIOLOGY, Issue 8 2002G. G. NICOLA 1.,Reproductive traits were studied in seven wild populations of resident brown trout in Spain. We examined whether growth, and certain environmental conditions such as water temperature or food abundance, could explain interpopulation variation in the reproductive characters. 2.,The results indicated that nearby populations subjected to a wide variation in environmental conditions exhibited a similar reproductive performance. 3.,Age distributions and sex ratios were not significantly different among populations. Age ranged from 0+ to 4+ years but the populations were dominated by the 0+ to 2+ groups. In all rivers females matured at age 2+ as opposed to age 1+ and 2+ for males. Mean length at the end of the growth period differed significantly among populations. However, annual growth rate was similar among rivers and was not significantly correlated with either biomass of the benthos or water temperature during the growth season. 4.,Reproductive effort, body condition, fecundity and egg size did not correlate significantly with either the abundance of benthic invertebrates or water temperature. Once the effect of body length on both egg size and number was removed, a significant negative correlation was found between these two traits among populations. [source] Nest-site selection by Great Bustards Otis tarda suggests a trade-off between concealment and visibilityIBIS, Issue 1 2010MARINA MAGAÑA Great Bustards Otis tarda have expanded their habitat range from historical occupancy of natural steppes to arable farmland, where the species initially benefited from favourable feeding conditions. More recently, the species has suffered severe declines due partly to agricultural intensification. Nest losses and juvenile mortality are amongst the factors most seriously affecting survival probabilities of many populations of this endangered species, suggesting that management of nesting habitats would bring conservation benefits. We studied nest-site selection in a Great Bustard population of central Spain by radiotracking 42 females for periods of between 1 and 4 years. Females selected nest-sites in fallows or cereal fields, in areas of low patch-type diversity, far from human infrastructure, and with good horizontal visibility. These results suggest that females look for shelter, but also need to have good visibility while incubating, and they support the hypothesis that nest selection is a trade-off between concealment and visibility. We interpret both preferences as adaptations to reduce predation pressure, one of the main causes of nest failure in this species. Nests were placed on slopes significantly orientated to the southeast, which suggests that females also seek sites protected from the cold north-westerly winds that are prevalent in the study area. To reduce nest destruction, harvesting should be delayed as long as possible and habitat conservation measures should not be restricted to lek sites but also include nesting areas, which are frequently located far from leks. [source] The Ciempozuelos Necropolis skull: a case of double trepanation?INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2003C. Liesau von Lettow-Vorbeck Abstract The focus of this study is the analysis of a trepanation performed on the skull of an adult male from the famous Bell Beaker necropolis of Ciempozuelos (Madrid) excavated at the end of the 19th century. The unusual characteristics of the pottery and other associated grave goods gave rise to the use of the name ,Ciempozuelos' to define the regional Bell Beaker style; this refers to similar finds from other sites on the Meseta of central Spain. Although trepanations from Chalcolithic contexts in the Iberian peninsula are not infrequent, they are unusual in Bell Beaker inhumations. Furthermore, this skull is exceptional not only for the type of trepanation performed, but also for the subsequent cranial deformation apparently resulting from the operation, as well as evidence of a second subsequent trepanation which indicates a very short post-surgical survival period for the individual. Copyright © 2003 John Wiley & Sons, Ltd. [source] Combined effects of climate and biotic interactions on the elevational range of a phytophagous insectJOURNAL OF ANIMAL ECOLOGY, Issue 1 2008Richard M. Merrill Summary 1The ranges of many species have expanded in cool regions but contracted at warm margins in response to recent climate warming, but the mechanisms behind such changes remain unclear. Particular debate concerns the roles of direct climatic limitation vs. the effects of interacting species in explaining the location of low latitude or low elevation range margins. 2The mountains of the Sierra de Guadarrama (central Spain) include both cool and warm range margins for the black-veined white butterfly, Aporia crataegi, which has disappeared from low elevations since the 1970s without colonizing the highest elevations. 3We found that the current upper elevation limit to A. crataegi's distribution coincided closely with that of its host plants, but that the species was absent from elevations below 900 m, even where host plants were present. The density of A. crataegi per host plant increased with elevation, but overall abundance of the species declined at high elevations where host plants were rare. 4The flight period of A. crataegi was later at higher elevations, meaning that butterflies in higher populations flew at hotter times of year; nevertheless, daytime temperatures for the month of peak flight decreased by 6·2 °C per 1 km increase in elevation. 5At higher elevations A. crataegi eggs were laid on the south side of host plants (expected to correspond to hotter microclimates), whereas at lower sites the (cooler) north side of plants was selected. Field transplant experiments showed that egg survival increased with elevation. 6Climatic limitation is the most likely explanation for the low elevation range margin of A. crataegi, whereas the absence of host plants from high elevations sets the upper limit. This contrasts with the frequent assumption that biotic interactions typically determine warm range margins, and thermal limitation cool margins. 7Studies that have modelled distribution changes in response to climate change may have underestimated declines for many specialist species, because range contractions will be exacerbated by mismatch between the future distribution of suitable climate space and the availability of resources such as host plants. [source] Maternal clutch reduction in the pied flycatcher Ficedula hypoleuca: an undescribed clutch size adjustment mechanismJOURNAL OF AVIAN BIOLOGY, Issue 6 2006Elisa Lobato During eight years of study of a population of pied flycatchers Ficedula hypoleuca breeding in central Spain, we observed throughout incubation 22 cases of intact eggs being placed on the nest rim and clearly outside of the nest bowl and remaining there, with consequent embryo mortality. We assume that the removal of eggs had been performed by the incubating female. There is no evidence that pied flycatcher parents can detect embryo mortality and eject unhatchable eggs. Maternal egg ejection constitutes a direct mechanism of clutch size adjustment during incubation and before hatching of any young of the brood. This adjustment of clutch size happened when the mean and minimum temperature of the day before ejection were especially low. Also, clutch-reducing females were significantly more prone to show moult-breeding overlap than other females, suggesting a lower disposition to invest in reproduction. Clutch-reducing females were also frequently older than four years and had indications of a lower immunocompetence than females not ejecting eggs. Our results support the hypothesis that adverse conditions can elicit parental family size adjustment at every stage of reproduction without the need to depend on mechanisms of sibling competition. [source] Tertiary relict trees in a Mediterranean climate: abiotic constraints on the persistence of Prunus lusitanica at the eroding edge of its rangeJOURNAL OF BIOGEOGRAPHY, Issue 8 2008Fernando Pulido Abstract Aim, To investigate the ecophysiological traits allowing persistence of a subtropical relict tree (Prunus lusitanica L.) under a dry Mediterranean climate at the eroding edge of its range. Location, A glasshouse for the study under controlled conditions and two marginal populations located in riparian forests of central Spain and exposed to summer drought, in contrast to subtropical populations that grow in mountain cloud forests. Methods, Two experiments were conducted to assess tolerance to the abiotic conditions found in riparian habitats. In a glasshouse experiment, gas-exchange and light-use parameters were measured to evaluate seedling responses to a factorial combination of irradiance (60%, 10%, 2% and 0.5% full sun) and moisture (well watered control and drought stress). In a parallel field experiment, irradiance and soil moisture were measured as predictors of seedling survival at two sites in which half the seedlings were subjected to a threefold increase in summer precipitation by adding water every 10 days. Results Soil moisture strongly determined survival both in the glasshouse and in the two field sites. In the field, periodic addition of water failed to increase survival. Water-use efficiency (WUE) increased with drought. Seedlings did not tolerate deep shade (2,0.5%) and their performance and survival were better when exposed to moderate (10%) or high (60%) irradiance. The effect of water stress on seedling performance was stronger at moderate irradiance, moderate at high irradiance and negligible at very low light. Seedling size (height and number of leaves) attained after 1 month of experimental treatments had a positive effect on survival at the end of the summer, hence greater survival was not achieved at the expense of vertical growth. Main conclusions, While studies in Macaronesia have shown that P. lusitanica occupies a wide range of moisture conditions along mountain slopes, it behaves as an obligate riparian species in dry peripheral populations. Intolerance to deep shade and tolerance to moderate and high irradiance allow the species to grow in small and moist gaps, or in treeless river sections. Despite the species' low range filling in marginal, drought-prone regions, long-term persistence might have been achieved through shifts to riparian habitats serving as local refuges. [source] Effects of forest fragmentation on European birds: implications of regional differences in species richnessJOURNAL OF BIOGEOGRAPHY, Issue 4 2003José Luis Tellería Abstract Aim, In this paper, we adopted a large-scale approach to evaluate the effect of regional richness of forest birds on the number of bird species retained by forest fragments in several localities across Europe. Location, We studied bird assemblages in fourteen forest archipelagos embedded in agricultural matrices from southern Norway to central Spain. Tree composition varied from oak and beech forests of the northern localities to oak and pine xerophitic woodlands of the southern ones. The number of fragments in each forest archipelago ranged from eighteen to 211. Methods, We used the Gleason equation (s = a + z log A; where s and A are, respectively, the species richness and size of forest fragments and z the rate of species loss) to estimate the species richness for 1- and 15-ha fragments in each archipelago. The regional richness of forest birds was estimated by modelling the geographical distribution of species richness in the European atlas of breeding birds. Results, The latitudinal distribution of regional richness displayed a convex form, with the highest values being in central Europe. Along this gradient, the number of species retained by fragments and the rate of species loss was positively related to regional richness. In addition, the percentage of the regional pool of species sampled by fragments decreased in the southern localities. Main conclusions, Relationships between regional richness of forest birds and richness in fragments seem to explain why fragments in central Europe shelter more species than their southern counterparts. The decreased ability of southern forest fragments to sample the regional richness of forest birds, could be explained as an effect of the low abundance of many species in the Mediterranean, which could depress their ability to prevent extinction in fragments by a rescue effect. Alternatively, high beta diversity in the Mediterranean could produce undersampling by fragments of the regional pool of species. These regional differences in the response of bird assemblages to forest fragmentation are used to discuss the usefulness of large-scale, biogeographical approaches in the design of conservation guidelines. [source] Abundance and habitat segregation in Mediterranean grassland species: the importance of seed weightJOURNAL OF VEGETATION SCIENCE, Issue 2 2002F.M. Azcárate Castroviejo (1986,1999); except taxa yet to be covered which follow Tutin et al. (1964,1980) Abstract. We analysed the relationship between seed traits (weight, shape and dispersal structures) and the abundance and habitat segregation of Mediterranean grassland species. To take into account possible correlations with other plant traits, the study also includes 5 vegetative traits (growth form, plant longevity, clonality, onset of flowering and plant size) of commonly accepted functional importance. Data were recorded for 85 species from dehesa grasslands in central Spain. Species abundance was measured in upper (dry and less productive, high stress) and lower (moist and more productive, low stress) slope zones in the same area. Habitat segregation was estimated using an index based on the relative frequencies of species in upper and lower slope zones. Multiple regression models were fitted using species, as well as phylogenetically independent contrasts, as data points. Annual small-seeded species without specialised dispersal structures are over-represented in dehesa grasslands. Abundance was negatively related to seed weight in upper slope zones. None of the recorded plant traits were related to abundance in the lower slope zones. Habitat segregation was mainly related to seed weight, but also to some vegetative traits. Annual, early flowering and small-seeded species were relatively more abundant in the upper than the lower slope zones. This pattern is independent of phylogeny. Our results suggest that in dry Mediterranean grasslands, abundance of many species is determined by dispersal (production of numerous small seeds) rather than by competitive ability. [source] Seasonal changes in prevalence and intensity of Hypoderma actaeon in Cervus elaphus from central SpainMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2001C. De La Fuente-López Summary Hypodermosis in red deer, Cervus elaphus Linnaeus (Artilodactyla: Cervidae), caused by the warble fly, Hypoderma actaeon Latreille (Diptera: Oestridae), was studied at Quintos de Mora (Toledo, Spain) over a one-year period between October 1994 and September 1995. One hundred and twenty-five red deer were examined for the presence of warble fly larvae. The prevalence of warbles was 44.8% and the intensity of infection was 38.29 (SD ± 61.32) warbles/deer infected. Clear seasonal variations were observed in prevalence and intensity, with the highest values in the autumn and winter. Statistically significant differences were observed in prevalence and intensity among age groups. In contrast, no differences were found in prevalence and intensity between males and females. [source] Text and image in celtiberia: the adoption and adaptation of written language into indigenous visual vocabularyOXFORD JOURNAL OF ARCHAEOLOGY, Issue 2 2003FIONA A. ROSE SummaryThis study is concerned with the relationships between text and image in central Spain during the period second century BC,second century AD. Three discrete relationships are isolated, each one representative of a unique strategy for communicating with both written and figured language. The paper argues that the Celtiberian populi adopted Roman epigraphic practice into a pre-existing visual vocabulary, reconfiguring written communication into an indigenous framework that met local predilections. [source] ROCK ART AND RITUAL LANDSCAPE IN CENTRAL SPAIN: THE ROCK CARVINGS OF LA HINOJOSA (CUENCA)OXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2003MARGARITA DÍAZ-ANDREU Summary. In this article the rock art carvings of La Hinojosa in central Spain are examined. Their connection to a major transit route recorded at least from the medieval period is explored, as well as their location in a valley located at the confluence of two primary river basins in the Iberian Peninsula separated by less than five kilometres. It is argued that this singularity of the landscape seems to have been perceived by the people who marked the stones. From the 17 decorated rocks recorded in La Hinojosa valley, three were exceptionally elaborately decorated. They were situated at regular intervals in the valley. The site with the greatest number of motifs, the large rock of San Bernardino, occupies a central location. This site is also exceptional because of the transformations which the rock shows throughout the day, pointing to a narrative in which cups and anthropomorphs seem to have a primary role. It is suggested that gender may have constituted one of the main guidelines of the narrative, given the apparent replacement of feminine by masculine human representations throughout the day. [source] Positive interactions between vulnerable species in agrarian pseudo-steppes: habitat use by pin-tailed sandgrouse depends on its association with the little bustardANIMAL CONSERVATION, Issue 4 2010C. A. Martín Abstract Positive interactions between species can have important conservation implications, especially when the species associating are both vulnerable. We studied the habitat use of pin-tailed sandgrouses Pterocles alchata and their association with another vulnerable species, the little bustard Tetrax tetrax in agrarian pseudo-steppes of central Spain using radio-tracking. The occurrence of mixed-species flocks varied seasonally, being more frequent in winter (65% of pin-tailed sandgrouse flocks). In this season, pin-tailed sandgrouses preferred stubble fields and fallows. Moreover, we found that habitat selection of pin-tailed sandgrouse depended on the association with little bustards in mixed-species flocks. When in mixed-species groups, sandgrouses changed their agrarian substrate preferences, and used stubble fields significantly more often than when in sandgrouse-only flocks. We also provide evidence that pin-tailed sandgrouse benefited from the anti-predator vigilance of little bustards, allowing sandgrouse to exploit new feeding grounds (stubble fields) that would otherwise be too risky to exploit. Our results indicate a close positive association between these two species, which are both declining in Europe, and we discuss implications for their management and conservation. We also recommend taking into account inter-specific positive interactions when designing conservation strategies for threatened species. [source] Response of pine natural regeneration to small-scale spatial variation in a managed Mediterranean mountain forestAPPLIED VEGETATION SCIENCE, Issue 4 2009Ignacio Barbeito Abstract Questions: What influence do management practices and previous tree and shrub stand structure have on the occurrence and development of natural regeneration of Pinus sylvestris in Mediterranean mountain forests? How are the fine-scale and environmental patterns of resources affected and what impact does this have on the distribution of the regeneration? Location: A Pinus sylvestris Mediterranean mountain forest in central Spain. Methods: Upperstory trees and regeneration (seedlings and saplings) were mapped in four 0.5-ha plots located in two types of stand with different management intensities (even-aged and uneven-aged stands). Environmental variables were recorded at the nodes of a grid within the plots. The relationships between the upperstory and regeneration were evaluated by bivariate point pattern analysis; redundancy analysis ordination and variation partitioning were performed to characterize regeneration niches and the importance of the spatial component. Results: Seedlings and saplings presented a clumped structure under both types of management and their distribution was found to be related to the spatial distribution of favourable microsites. Regeneration was positively related to conditions of partial cover with high soil water content during the summer. More than half of the explained variance was spatially structured in both types of stand. This percentage was particularly high in the even-aged stands where the pattern of regeneration was highly influenced by the gaps created by harvesting. Conclusions: The spatial distribution of the tree and shrub upperstory strongly influences regeneration patterns of P. sylvestris. Current management practices, promoting small gaps, partial canopy cover and moderate shade in even-aged stands, or favouring tree and shrub cover in the case of uneven-aged stands, appears to provide suitable conditions for the natural regeneration of P. sylvestris in a Mediterranean climate. [source] | ||||||||||||||||||||||||||||||||||