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Northeastern Spain (northeastern + spain)
Selected AbstractsEffects of field reorganisation on the spatial variability of runoff and erosion rates in vineyards of Northeastern SpainLAND DEGRADATION AND DEVELOPMENT, Issue 1 2010M. C. Ramos Abstract This study analyses the spatial variability of runoff and erosion rates in vineyards due to mechanisation works. Runoff samples were collected at three positions in two plots after 33 erosive events in three years (2001, 2003, 2004) with different rainfall patterns. Three replications were considered at each position. Soil properties were evaluated in order to analyse its relationship with runoff and erosion rates. Runoff and erosion rates were, on average, higher in the levelled plot (HD), ranging between 8·4 and 34·3 per cent, than in the non-levelled plot (LD) ranging between 8·2 and 24·1 per cent. Mean sediment concentration in runoff ranged between 6 and 8,g,L,1 in the HD plot and about 4·6,g,L,1 in the LD plot, but with high differences within the plot. In the HD plot, runoff-rainfall rates were significantly higher (at 95 per cent level) in the upper part of the slope and decreased along the slope, while in the LD plot, differences in runoff rates were not significant and similar to those observed in the less disturbed areas of the HD plot. The higher susceptibility to soil sealing in areas where the original topsoil was removed conditioned runoff rates. In the lower part of the HD plot runoff rates were, on average, 20 per cent lower than in the upper part of the slope. In those positions runoff rates up to 79 per cent were recorded. Organic matter content and water retention capacity at different potentials are the soil characteristics related to the differences on runoff and erosion rates in the resulting soils. Copyright © 2009 John Wiley & Sons, Ltd. [source] The microstratigraphic record of abrupt climate changes in cave sediments of the Western MediterraneanGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 5 2001Marie-Agnès Courty The purpose of this paper is to illustrate how calcareous sediments from Pleistocene and Holocene rockshelters and open caves of the Western Mediterranean can provide a stratigraphic record of abrupt climate change. The method proposed here is based on microstratigraphic examination of sedimentary sequences using microscopic techniques. The most important processes for characterizing the sensitivity of each cave to climate variables are: (1) the modes and rate of carbonate sediment production, (2) the nature and intensity of the pedogenic processes responsible for the synchronous alteration of carbonate materials (either those derived from the cave walls or those deposited on the ground surface), and (3) the supply of allogenic sediments, particularly by eolian activity. The cave sediment sequences presented record the marked coolings known as Dansgaard-Oeschger stadials and Heinrich events that occurred during the Pleistocene and the Holocene, as demonstrated by the high resolution records from ice and deep sea cores. At Abric Romanì in northeastern Spain, a series of sharp climatic deteriorations of increasing severity is shown to have occurred synchronously with the transition from the Middle to the Upper Paleolithic, with a period of seasonal frost and strong winds at ca. 37,000 yr B.P., tentatively correlated with Heinrich event 4. At Pigeon Cave, Taforalt (northern Morocco), the transition from the Aterian to Ibero-Maurusian/Epipalaeolithic cultures is dated to around 24,000,20,000 yr B.P. and is punctuated by a series of short cold pulses with evidence for seasonal freezing, soil erosion, and minimal evapotranspiration. In El Miron cave in north-central Spain, the exceptional nature of the Younger Dryas cooling produced a marked destabilization of the cave walls and roof. At El Miron, the stratigraphic evidence for sediment removal due to the rapid percolation of snow melt under a degraded soil cover allows us to reconstruct the nature of the negative excursion at ca. 8200 yr B.P. This example also illustrates how climate-controlled pedogenic processes can create a stratigraphic signature which has often been confused with a sedimentary hiatus. We conclude that cave sediments provide a valuable record of Pleistocene and Holocene climate changes. In appropriate contexts, these sequences allow us to examine the ecological stress generated by these unique global events at a local and regional level and improve our understanding of the complex anthropological processes that occurred at the same time. © 2001 John Wiley & Sons, Inc. [source] The Politics of Belonging: Complexities of Identity in the Catalan BorderlandsGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 3 2001Jouni Häkli The rise of the European nation,state system profoundly influenced the map of linguistic and cultural minorities. Catalonia in northeastern Spain is no exception. The consolidation of the Spanish and French kingdoms during the sixteenth and seventeenth centuries left Catalan speakers without political and cultural sovereignty. Furthermore, in the Treaty of the Pyrenees of 1659, the Catalan homeland els Països Catalans was divided by the Franco,Spanish border. Today, Catalan culture and politics enjoy increasing latitude in both Spain and France. This has encouraged various forms of cross,border co,operation in the Catalan borderlands. It has also led many Catalan nationalists to expect still greater political autonomy. Some activists have voiced claims for independence and even the reincorporation of the Spanish (el Principat) and French Catalonias (Catalunya Nord). However, political tensions regarding the borderland's development exist between the local actors and the Spanish and French national governments, as well as between Catalan nationalists and the population at large. This article examines these tensions, first by looking at cross,border co,operation efforts in Catalonia, and second by assessing the visible markers of identity that Catalan nationalists have placed in the border landscapes. These are contrasted with the results of a survey charting the opinions and attitudes of ,ordinary' Catalans. The article argues that there are significant cleavages among Catalans, and that the era of the nation,states has left a legacy of complex loyalties at international frontiers. [source] Soil water content and yield variability in vineyards of Mediterranean northeastern Spain affected by mechanization and climate variabilityHYDROLOGICAL PROCESSES, Issue 11 2006M. C. Ramos Abstract The objective of this paper was to analyse the combined influence of the Mediterranean climate variability (particularly the irregular rainfall distribution throughout the year) and the land transformations carried out in vineyards of northeastern Spain on soil water content evolution and its influence on grape production. The study was carried out in a commercial vineyard located in the Anoia,Alt Penedès region (Barcelona province, northeastern Spain), which was prepared for mechanization with important land transformations. Two plots were selected for the study: one with low degree of transformation of the soil profile, representing a non-disturbed situation, and the second one in which more than 3 m were cut in the upper part of the plot and filled in the lower part, representing the disturbed situation. Soil water content was evaluated at three positions along the slope in each plot and at three depths (0,20, 20,40, 40,60 cm) during the period 1999,2001, years with different rainfall characteristics, including extreme events and long dry periods. Rainfall was recorded in the experimental field using a pluviometer linked to a data-logger. Runoff rates and yield were evaluated at the same positions. For the same annual rainfall, the season of the year in which rainfall is recorded and its intensity are critical for water availability for crops. Soil water content varies within the plot and is related to the soil characteristics existing at the different positions of the landscape. The differences in soil depth created by soil movements in the field mechanization give rise to significant yield reductions (up to 50%) between deeper and shallow areas. In addition, for the same annual rainfall, water availability for crops depends on its distribution over the year, particularly in soils with low water-storage capacity. The yield was strongly affected in years with dry or very dry winters. Copyright © 2005 John Wiley & Sons, Ltd. [source] A solar-powered transmitting video camera for monitoring cliff-nesting raptorsJOURNAL OF FIELD ORNITHOLOGY, Issue 1 2006Antoni Margalida ABSTRACT We designed a system of solar-powered video cameras that transmitted images via telemetry to a monitor. This system allowed us to study the breeding behavior of the Bearded Vulture (Gypaetus barbatus) in the Pyrenees (northeastern Spain). From 2000 to 2004, 12 nests in seven territories were equipped with video cameras. To avoid disturbing the birds, equipment was installed 3,8 weeks before egg-laying. The acceptance rate was 75%. No decline in productivity was observed for nests monitored with video cameras compared to control nests. The cameras enabled us to document egg-laying, hatching asynchrony, the nestlings' diet, and the parents' breeding behavior from distances of 2,3 km, although technical problems temporarily interrupted the transmission of images. Video cameras can be used successfully to study the Bearded Vultures, and probably other cliff-nesting raptors, without reducing productivity. SINOPSIS Diseñamos un sistema de cámaras de vídeo alimentado por energía solar que transmite imágenes por telemetría a un monitor. Este sistema permitió estudiar el comportamiento reproductor del Quebrantahuesos (Gypaetus barbatus) en los Pirineos (NE España). Durante el periodo de 2000,2004 se equiparon con cámaras de video 12 nidos en siete territorios. Los equipos se instalaron entre 3 y 8 semanas antes de la puesta, para reducir las molestias a las aves. El éxito de aceptación fue del 75%. No se observó un descenso en la productividad de los nidos estudiados con las cámaras con respecto a los no equipados con dicho sistema. El sistema permitió documentar a una distancia de 2,3 kms, la asincronía de puesta y eclosión, la dieta del pollo y el comportamiento de los adultos en el nido, aunque se detectaron algunos problemas técnicos que temporalmente interrumpieron la emisión de las imágenes. Las cámaras de vídeo pueden ser utilizadas para estudiar a otras aves rupícolas sin afectar la productividad. [source] Occurrence, Symptom Expression and Characterization of Phytoplasma Associated with Pear Decline Disease in Catalonia (Spain)JOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2003M. Garcia-Chapa Abstract A total area of 1500 ha of commercial plots was surveyed to study the extent of pear decline disease and its relative importance in northeastern Spain. A preliminary evaluation indicated that around 7% of the plots had symptoms of the disease. At the same time, pear decline incidence was evaluated in 45 plots, by visual inspection of 500 trees in each plot. In September, the incidence of trees with symptoms ranged from 8 to 59% depending on the cultivar selected. The presence of pear decline (PD) phytoplasma in these plots was confirmed by polymerase chain reaction (PCR) amplification of phytoplasma DNA with universal or group-specific primers. Restriction fragment length polymorphism analyses also showed the presence of a unique phytoplasma strain. The symptom expression of PD disease in different cultivars was evaluated throughout the year. The relationship between the presence of symptoms and detection of PD by PCR in these cultivars was also studied. Results showed that the nested-PCR, using specific primers to detect the DNA from PD phytoplasma, is the most accurate method to identify the total percentage of affected trees. [source] Plant traits enabling survival in Mediterranean badlands in northeastern Spain suffering from soil erosionJOURNAL OF VEGETATION SCIENCE, Issue 4 2008Joaquín Guerrero-Campo Abstract Question: This study analysed the effect of severe soil erosion on species composition of plant communities by favouring species showing certain growth forms, root-sprouting and clonal growth abilities. Location: The study area was located between the middle Ebro Valley and the Pre-Pyrenees (northeastern Spain). Methods: Root-sprouting and shoot-rooting abilities, clonal reproduction and growth form were assessed for the 123 most common plant species from eroded lands in the study area. We obtained 260 vegetation relevés in three different substrata (gypsum outcrops, Miocene clays and Eocene marls) on areas with different degrees of soil erosion. The frequency of every plant trait in each relevé was estimated according to species presence. The effect of soil erosion on the frequency of plant attributes was assessed by correlation analyses. Results: Bipolar, non-clonal plants and annual species decreased their frequency with increasing soil erosion in the three substrata analyzed, whereas root-sprouters and woody plants (mostly sub-shrubs) increased their frequency in most of the substrata analysed. Conclusions: Woody sub-shrubs, root-sprouters and clonal species are favoured in eroded lands in NE Spain. Bipolar species and annual plants might not be plastic enough to survive the high stress and frequent disturbances prevailing in such eroded areas. [source] | |||||||||||||