Innovación socioeducativa para el apoyo de adolescentes en situación de acogimiento familiar

Este artículo presenta los resultados de la investigación sobre los adolescentes acogidos en familias extensas. Este proyecto se sitúa en la investigación cooperativa. La muestra está compuesta por 57 jóvenes acogidos y 79 técnicos expertos en protección de la infancia de ocho regiones españolas. Los resultados indican que los jóvenes acogidos tienen deseos diferenciales que demandan una respuesta específica que hemos concretado en la creación del «programa de apoyo para adolescentes de acogida». A continuación se mostrarán las principales características de este programa; se hará, también, una reflexión sobre sus aspectos fundamentales, es decir, la ayuda a los técnicos para que ellos puedan obtener un nuevo recurso de formación e intervención grupal introduciendo como método la promoción de la resiliencia.

Influencia de las TIC en la utilización de materiales y recursos en los procesos de enseñanza-aprendizaje de la Universidad de Lleida: ¿uso o abuso?

El artículo es un estudio realizado con el objetivo de observar la utilización de recursos de aprendizaje en diferentes asignaturas presenciales, semipresenciales y no presenciales de la Universidad de Lleida. La investigación se desarrolló bajo la modalidad de estudio de casos, recogiendo datos de profesorado y estudiantado a través de análisis documental, cuestionarios y entrevistas. El estudio mostró que, independientemente de la modalidad formativa de las asignaturas, se utilizaba una variedad considerable de recursos para hacer llegar la información a los estudiantes, aunque se detectó una baja mediación entre los materiales que el profesorado publicaba y el acceso a estos por parte de los estudiantes. Consideramos que todavía queda camino por recorrer en el aprovechamiento de los recursos TIC en los procesos formativos universitarios.

Irrigation performance and gross water productivity in furrow-irrigated ornamental tree production

In the ornamental plant production region of Girona (Spain), which is one of the largest of its kind in southern Europe, most of the surface is irrigated using wide blocked-end furrows. The objectives of this paper were: (1) to evaluate the irrigation scheduling methods used by ornamental plant producers; (2) to analyse different scenarios in order to assess how they affect irrigation performance; (3) to evaluate the risk of deep percolation; and (4) to calculate gross water productivity. A two-year study in a representative commercial field, planted with Prunus cerasifera ‘Nigra’, was carried out. The irrigation dose applied by the farmers was slightly smaller than the required water dose estimated by the use of two different methods: the first based on soil water content, and the second based on evapotranspiration. Distribution uniformity and application eff iciency were high, with mean values above 87%. Soil water content measurements revealed that even at the end of the furrow, where the infiltrated water depth was greatest, more than 90% of the infiltrated water was retained in the shallowest 40 cm of the soil; accordingly, the risk of water loss due to deep percolation was minimal. Gross water productivity for ornamental tree production was € 11.70 m–3, approximately 20 times higher than that obtained with maize in the same region.

Postharvest quality and chilling injury of plums: benefits of 1-methylcyclopropene

The aim of this work was to evaluate the effect of 1-methylcyclopropene (1-MCP) treatment on the development of chilling injury (CI) symptoms in four plum cultivars and to determine the relationship between the climacteric behavior of the cultivar and its sensitivity to this disorder. Significant differences in ripening pattern were found between the cultivars after long-term storage. Among the climacteric cultivars, ‘Royal Zee’ plums showed a higher ethylene production rate than ‘Linda Rosa and ‘Friar’ cultivars. On the other hand, the ‘Angeleno’ cultivar behaved as a suppressed climacteric type. The development of translucency symptoms was higher in ‘Royal Zee’ than in ‘Linda Rosa’ and ‘Friar’ plums, and was almost absent in the suppressed climacteric cultivar. 1-MCP treatment significantly reduced ethylene production and the percentage of fruit affected by translucency in all climacteric cultivars. This treatment also delayed the ripening of the fruit during shelf life. In contrast, 1-MCP treatment did not affect the quality of ‘Angeleno’ plums. Collectively these results suggest that the development of chilling injury in plums is related to the climacteric behavior of the cultivar and demonstrated the beneficial effects of 1-MCP maintaining plum quality during storage.

Clustering of grape yield maps to delineate site-specific management zones

Zonal management in vineyards requires the prior delineation of stable yield zones within the parcel. Among the different methodologies used for zone delineation, cluster analysis of yield data from several years is one of the possibilities cited in scientific literature. However, there exist reasonable doubts concerning the cluster algorithm to be used and the number of zones that have to be delineated within a field. In this paper two different cluster algorithms have been compared (k-means and fuzzy c-means) using the grape yield data corresponding to three successive years (2002, 2003 and 2004), for a ‘Pinot Noir’ vineyard parcel. Final choice of the most recommendable algorithm has been linked to obtaining a stable pattern of spatial yield distribution and to allowing for the delineation of compact and average sized areas. The general recommendation is to use reclassified maps of two clusters or yield classes (low yield zone and high yield zone) and, consequently, the site-specific vineyard management should be based on the prior delineation of just two different zones or sub-parcels. The two tested algorithms are good options for this purpose. However, the fuzzy c-means algorithm allows for a better zoning of the parcel, forming more compact areas and with more equilibrated zonal differences over time.

Phosphorous and nitrogen changes in compost-amended schist soils in vineyards in the D.O. Priorat wine-producing area (NE Spain)

The impact, on nitrogen and phosphorous dynamics, of applying compost at different rates was investigated in soils developed on schist in new terraced vineyards (NTV) and in undisturbed areas (NC). Repacked soil columns amended with 0 (control), 50 t ha –1 (T1) and 100 t ha–1 (T2) of compost were studied under laboratory conditions simulating both situations. The columns were maintained for 1 year, during which time a total of 300 mm of simulated rainfall was applied in ten 30 mm applications. Soil organic matter (OM), nitrogen and phosphorous contents were analysed at the end of the study period and leachates were analysed after each simulated rainfall event. Significant differences in nitrate leaching were observed between the control and the treated soils and these differences were greater in the NC (control = 1.368 g, T1 = 1.526 g and T2 = 1.686 g) than in the NTV soils (control = 0.61 g, T1 = = 1.068 g and T2 = 1.283 g). The relative effect was greater in the NTV soils (T1/control = 1.11 vs. 1.75 and T2/control = 1.23 vs. 2.1 for NC and NTV, respectively). The nitrate concentration in the leached water reached up to 400 mg L–1, which implied a risk of groundwater pollution. Phosphorous losses through leaching were very low with concentrations of < 0.15 mg L–1, without any significant differences between treatments. The phosphorous concentrations in the surface horizon increased by 50.8% in T1 and by 66.8% in T2 in the NC soils, compared with increases of 20.3% and 38%, respectively, in the NTV soils. Due to the high infiltration capacity of the study soils, leaching effects must be considered in order to prevent groundwater pollution.

Short communication. Potential to mitigate anthropogenic CO2 emissions by tillage reduction in dryland soils of Spain

Spain is one of the countries with the highest greenhouse gas (GHG) emissions within the EU-27. Consequently, mitigation strategies need to be reported and quantified to accomplish the goals and requirements of the Kyoto Protocol. In this study, a first estimation of the carbon (C) mitigation potential of tillage reduction in Mediterranean rainfed Spain is presented. Results from eight studies carried out in Spain under rainfed agriculture to investigate the effects of no-tillage (NT) and reduced tillage (RT) compared with conventional tillage (CT) on soil organic carbon (SOC) were used. For current land surface under conservation tillage, NT and RT are sequestering 0.14 and 0.08 Tg C yr-1, respectively. Those rates represent 1.1% and 0.6% of the total CO2 emissions generated from agricultural activities in Spain during 2006. Alternatively, in a hypothetical scenario where all the arable dryland was under either NT or RT management, SOC sequestration would be 2.18 and 0.72 Tg C yr-1 representing 17.4% and 5.8% of the total 2006 CO2 equivalent emissions generated from the agricultural sector in Spain. This is a significant estimate that would help to achieve GHG emissions targets for the current commitment period of the Kyoto Protocol.

Meat characteristics of chickens from an F1 cross of two improved Spanish breeds depending on slaughter age

The present study analysed the meat characteristics of i) improved Castellana Negra chickens slaughtered at 18 weeks (CN-18) and ii) F1 crossbred chickens from improved Castellana Negra hens and improved Penedesenca Negra cocks (CNPN) slaughtered at 12 weeks and 18 weeks of age (young and adult animals, respectively). Purebred and crossbred specimens were compared at similar weights (CN-18 and CNPN-12) and ages (CN-18 and CNPN-18). The protein content of the meat was similar for the three types of animals; heavier animals (CNPN-18) had more fat than those slaughtered at lower weights (CNPN-12 and CN-18). Adults had a higher saturated fatty acid content and the young CNPN chickens had more monounsaturated fatty acids than CN chickens. In the CNPN adults, less water was lost during cooking, which is directly related to the juiciness of the meat. With regard to sensory analysis, a darker colour was observed in the meat as much as the internal fat of adult animals, in addition to greater colour uniformity. The meat of young CNPN birds was juicier, whereas that of the CN chickens was more fibrous. Therefore, we conclude that meat from CNPN chickens presents chemical, physical, and sensorial characteristics that make these animals a genetic base for alternative poultry production.

Analysis of vineyard differential management zones and relation to vine development, grape maturity and quality

The objective of research was to analyse the potential of Normalized Difference Vegetation Index (NDVI) maps from satellite images, yield maps and grapevine fertility and load variables to delineate zones with different wine grape properties for selective harvesting. Two vineyard blocks located in NE Spain (Cabernet Sauvignon and Syrah) were analysed. The NDVI was computed from a Quickbird-2 multi-spectral image at veraison (July 2005). Yield data was acquired by means of a yield monitor during September 2005. Other variables, such as the number of buds, number of shoots, number of wine grape clusters and weight of 100 berries were sampled in a 10 rows × 5 vines pattern and used as input variables, in combination with the NDVI, to define the clusters as alternative to yield maps. Two days prior to the harvesting, grape samples were taken. The analysed variables were probable alcoholic degree, pH of the juice, total acidity, total phenolics, colour, anthocyanins and tannins. The input variables, alone or in combination, were clustered (2 and 3 Clusters) by using the ISODATA algorithm, and an analysis of variance and a multiple rang test were performed. The results show that the zones derived from the NDVI maps are more effective to differentiate grape maturity and quality variables than the zones derived from the yield maps. The inclusion of other grapevine fertility and load variables did not improve the results.

Progress in the Spanish National Barley Breeding Program

The Spanish Barley Breeding Program is carried out by four public research organizations, located at the most representative barley growing regions of Spain. The aim of this study is to evaluate the program retrospectively, attending to: i) the progress achieved in grain yield, and ii) the extent and impact of genotype-by-environment interaction of grain yield. Grain yields and flowering dates of 349 advanced lines in generations F8, F9 and F10, plus checks, tested at 163 trials over 11 years were analized. The locations are in the provinces of Albacete, Lleida, Valladolid and Zaragoza. The data are highly unbalanced because the lines stayed at the program for a maximum of three years. Progress was estimated using relative grain yield and mixed models (REML) to homogenize the results among years and locations. There was evident progress in the program over the period studied, with increasing relative yields in each generation, and with advanced lines surpassing the checks in the last two generations, although the rate of progress was uneven across locations. The genetic gain was greater from F8 to F9 than from F9 to F10. The largest non-purely environmental component of variance was genotype-by-location-by-year, meaning that the genotype-by-location pattern was highly unpredictable. The relationship between yield and flowering time overall was weak in the locations under study at this advanced stage of the program. The program can be continued with the same structure, although measures should be taken to explore the causes of slower progress at certain locations.

Post-market environmental monitoring of Bt maize in Spain: Non-target effects of varieties derived from the event MON810 on predatory fauna

The Spanish Government has established post-market environmental monitoring (PMEM) as mandatory for genetically modified (GM) crop varieties cultivated in Spain. In order to comply with this regulation, effects of Bt maize varieties derived from the event MON810 on the predatory fauna were monitored for two years in northeast and central Spain. The study was carried out with a randomized block design in maize fields of 3-4 ha on which the abundance of plant-dwelling predators and the activity-density of soil-dwelling predators in Bt vs. non-Bt near-isogenic varieties were compared. To this end, the plots were sampled by visual inspection of a certain number of plants and pitfall traps 6 or 7 times throughout two seasons. No significant differences in predator densities on plants were found between Bt and non-Bt varieties. In the pitfall traps, significant differences between the two types of maize were found only in Staphylinidae, in which trap catches in non-Bt maize were higher than in Bt maize in central Spain. Based on the statistical power of the assays, surrogate arthropods for PMEM purposes are proposed; Orius spp. and Araneae for visual sampling and Carabidae, Araneae, and Staphylinidae for pitfall trapping. The other predator groups recorded in the study, Nabis sp. and Coccinellidae in visual sampling and Dermaptera in pitfall trapping, gave very poor power results. To help to establish a standardized protocol for PMEM of genetically modified crops, the effect-detecting capacity with a power of 0.8 of each predator group is given.

La influencia de las TIC en la interacción docente y discente en los procesos formativos universitarios

La interacción, un elemento básico en cualquier proceso formativo, debe replantearse con la irrupción de la tecnología. Con la intención de abordar los cambios metodológicos que las TIC implican en la docencia desde la perspectiva de la interacción que generan, se planteó un estudio en la Universidad de Lérida para observar los procesos que interactúan en diferentes asignaturas en función de si éstas se desarrollaban bajo la modalidad presencial, semipresencial o no presencial. El diseño metodológico se articuló alrededor de tres técnicas de recogida de datos: análisis documental de programas de asignaturas, cuestionarios a profesores y estudiantes y entrevistas a profesores. Los datos mostraron que, conforme aumenta la no presencialidad de las asignaturas, profesorado y estudiantado utilizaban más herramientas tecnológicas (correo electrónico, foro, chat, redes sociales...) para comunicarse. Además, el tipo de comunicación imperante tenía finalidades académicas, mientras que se producía una escasa interacción para aspectos más personales (de orientación, apoyo...); en este sentido, tanto profesorado como estudiantado preferirían un contacto más cercano no tan centrado en los elementos académicos del proceso. También observamos que en las asignaturas en línea se desarrolla un trabajo más individual por parte del estudiantado. Aunque todavía queda camino por recorrer en la interacción docente-discente a través de las TIC, los agentes implicados en el proceso reconocen sus potencialidades, pero aún no las utilizan como consideran que convendría hacerse.

Variabilidad espacial del arroz como cultivo indicador de salinidad en regadíos del valle del Ebro a partir de series temporales en imágenes Landsat TM

El presente trabajo pretende la caracterización de la distribución espacial típica del cultivo de arroz en regadíos del valle del Ebro, donde la presencia del cultivo está ligada a la existencia de suelos salino-sódicos. Esta caracterización ha de permitir identificar las áreas donde es típica la presencia del cultivo año tras año y las áreas donde es frecuente su fluctuación debido tanto a condiciones variables de salinidad del suelo como a variabilidad en las condiciones de mercado. Para ello se ha recurrido al análisis de una serie temporal de mapas de cultivos (7 años) derivados de la clasificación supervisada de imágenes Landsat TM. La determinación de las áreas típicas y de fluctuación del cultivo de arroz se hace entonces a partir del análisis estadístico de clases, y mediante superposición espacial de coberturas en un entorno SIG-Raster.

Aplicación de imágenes radar de satélite a la cartografía de la vegetación en zonas boreales

El presente estudio se enmarca en el proyecto europeo SIBERIA. Trata de explorar el uso de imágenes radar de satélite (ERS y JERS) para la actualización de la cartografía de vegetación de zonas boreales. Se dispone de 8 imágenes de amplitud y coherencia tomadas en 1998, así como de un inventario de vegetación georreferenciado de dos pequeñas zonas. Se proponen tres tipos de clasificaciones supervisadas por el método de máxima verosimilitud. La primera con las imágenes de satélite, la segunda añadiendo algunas imágenes texturales, y la tercera utilizando sólo las imágenes de los componentes principales más significativos. Se siguen los criterios establecidos en el proyecto SIBERIA para la obtención de áreas de entrenamiento. Se propone una doble validación, por una parte vía matrices de confusión a partir de áreas de verdad-terreno obtenidas por el mismo método que las áreas de entrenamiento, y por otra parte contrastando y correlacionando las clasificaciones con los parámetros de inventario disponibles para dos pequeñas áreas de verdad-terreno. Los resultados indican una sensible mejora en la clasificación con la incorporación de imágenes texturales (la precisión aumenta de un 66% a un 75%), y señalan el parámetro biomasa como el mejor correlacionado con las clasificaciones derivadas (coeficiente de correlación r de hasta 0,49). Diferentes fuentes de error permiten augurar un margen de mejora para posteriores estudios.

Los juegos y deportes tradicionales en Europa: entre la tradición y la modernidad

El juego es un elemento básico de socialización: es una creación cultural en el marco de una sociedad determinada. La visión contextualizada de todo juego tradicional debe considerar las propiedades que caracterizan su lógica interna, así como las condiciones socioculturales y los significados simbólicos que le atribuyen sus protagonistas (lógica externa). En esta investigación se realiza un inventario y análisis de la lógica interna y la lógica externa de los juegos tradicionales de adultos que se practican actualmente en 11 regiones europeas. Entre las conclusiones más relevantes destacar que existe un gran repertorio de juegos psicomotores y sociomotores. Se trata de juegos con un alto componente competitivo, en los que se distinguen vencedores y perdedores. Los grupos son básicamente masculinos y mixtos y sin la presencia de un líder o capitán, excepto en las regiones más deportivizadas en las que si aparece esta figura. Se observa que muchas de estas prácticas se están transformando en deportes (regionales), sobre todo aquellas que son protagonizadas por el género masculino. En definitiva, esta investigación aporta datos muy relevantes para comprender la naturaleza de la cultura lúdica tradicional europea.