Comunicación corta. Respuesta del garbanzo a las aplicaciones de zinc al suelo

[EN] The response of chickpea (Cicer arietinum) to Zn nutrition was studied in pot experiments under natural conditions using four acid soils of northwest Spain during 2007 and 2008. Five concentrations of Zn (0, 1, 2, 4 and 8 mg Zn pot–1) were added to the pots as Zn chelate. Chickpea responded to the soil Zn applications and there were highly significant differences between soils. At maturity plants fertilized with Zn had greater total dry matter production mainly due to increments in pods weight. The lowest yield (2.65 g plant–1) was obtained from 0 mg Zn pot–1, while the highest yield (3.52 g plant–1) was recorded at 4 mg Zn pot–1. The increased yields in Zn applied plants was the result of increased number of pods per plant. Furthermore, this yield component was closely correlated with the seed yield[ES] Se estudió la respuesta del garbanzo cultivado en macetas al aire libre a las aplicaciones de Zn usando cuatro suelos del noroeste de España durante 2007 y 2008. Cinco concentraciones de Zn (0, 1, 2, 4 y 8 mg Zn maceta–1) fueron añadidas a las macetas. El garbanzo respondió a las aplicaciones de Zn al suelo, existiendo diferencias altamente significativas entre los suelos. A la madurez, las plantas de las macetas fertilizadas con Zn tenían una mayor producción total, principalmente por el incremento del peso seco de las vainas. El menor rendimiento (2,65 g planta–1) se obtuvo en las macetas con 0 mg Zn maceta–1, mientras que el mayor rendimiento (3,52 g planta–1) se alcanzó con 4 mg Zn planta–1. El incremento del número de vainas por planta fue el responsable del incremento de rendimiento. El número de vainas por planta fue el componente del rendimiento más directamente correlacionado con el rendimiento en semilla por plantaS

Effect of different times and techniques of molybdenum applicationon chickpea (Cicer arietinum) growth and yield

[EN] Molybdenum (Mo) plays an important role in increasing chickpea yield. In 2009, we studied the effects of different Mo application times and techniques on the response of the Kabuli chickpea (Cicer arietinum) to Mo nutrition. Pot experiments were conducted under natural conditions using two different soils from northwest Spain and following a factorial statistical pattern (7 × 2) with six replicates for each soil. A treatment of 2 mg Mo pot–1 was added to the pots at six different moments, 1 to 6 weeks after emergence (WAE), using two different application techniques (soil and foliar). Both growth and yield were affected by Mo application, but yield was more affected than total dry matter. The response was greater in the medium acid soil than in the neutral-slightly basic soil. At maturity, plants fertilized at 4 WAE produced a greater seed yield, mainly due to an increase in the number of pods per plant. Foliar Mo application was more effective, and soil Mo application should be carried out earlier in the cycle. An interaction was found between time and technique of Mo application, with the highest yield being obtained when Mo was applied at 4 WAE using foliar fertilization[ES] El molibdeno (Mo) juega un papel importante en el incremento del rendimiento del garbanzo. Se estudió durante 2009 la respuesta del garbanzo (tipo Kabuli) cultivado en macetas al aire libre a las aplicaciones de Mo en diferentes épocas y utilizando dos técnicas diferentes de aplicación, usando dos suelos distintos del noroeste de España según un diseño factorial (7 × 2) con seis repeticiones para cada suelo. Se añadieron 2 mg Mo maceta–1 en seis épocas diferentes, desde la primera semana después de la emergencia hasta la sexta, utilizando dos técnicas de aplicación distintas (al suelo y foliar). El crecimiento y el rendimiento se vieron afectados por la aplicación de Mo, siendo el rendimiento más afectado que la materia seca total. La respuesta fue mayor en el suelo medianamente ácido que en el suelo neutro-ligeramente básico. En la madurez, las plantas fertilizadas con Mo a las 4 semanas después de la emergencia dieron un rendimiento mayor, principalmente debido a un aumento en el número de vainas por la planta. El aumento fue mayor en el suelo medianamente ácido. La aplicación foliar de Mo fue más eficaz; mientras que la aplicación de Mo al suelo debe llevarse a cabo en épocas más tempranas. Se encontró interacción entre la época y la técnica de aplicación de Mo, obteniéndose el rendimiento más alto cuando el Mo fue aplicado vía foliar a las 4 semanas después de la emergenciaS

Binaural pre-processing for contralateral sound field attenuation and improved speech-in-noise recognition

Understanding speech presented in competition with other sounds can be challenging. Here, we reason that in free-field settings, this task can be facilitated by attenuating the sound field contralateral to each ear and propose to achieve this by linear subtraction of the weighted contralateral stimulus. We mathematically justify setting the weight equal to the ratio of ipsilateral to contralateral head-related transfer functions (HRTFs) averaged over an appropriate azimuth range. The algorithm is implemented in the frequency domain and evaluated technically and experimentally for normal-hearing listeners in simulated free-field conditions. Results show that (1) it can substantially improve the signal-to-noise ratio (up to 30 dB) and the short-term objective intelligibility in the ear ipsilateral to the target source, particularly for maskers with speech-like spectra; (2) it can improve speech reception thresholds (SRTs) for sentences in competition with speech-shaped noise by up to 8.5 dB in bilateral listening and 10.0 dB in unilateral listening; (3) for sentences in competition with speech maskers and in bilateral listening, it can improve SRTs by 2 to 5 dB, depending on the number and location of the masker sources; (4) it hardly affects virtual sound-source lateralization; and (5) the improvements, and the algorithm's directivity pattern depend on the azimuth range used to calculate the weights. Contralateral HRTF-weighted subtraction may prove valuable for users of binaural hearing devices

Sistema electoral para Andalucía

El sistema electoral para la elección del parlamento de Andalucía tiene similitudes con el correspondiente al Congreso de los diputados, y lo mismo ocurre con casi todos los sistemas electorales de las diferentes comunidades autónomas. Varias de ellas, por ejemplo Canarias y Madrid, además de Andalucía, se han propuesto reformar su sistema electoral en esta legislatura. En este trabajo se recogen principios para conseguir un sistema electoral representativo y que incentive la gobernabilidad. Además se aplican esos principios para elaborar alternativas al sistema electoral para el parlamento de Andalucía y se muestra una simulación con resultados correspondientes a las últimas elecciones, las celebradas en 2015

Geomorphic impact and assessment of flexible barriers using multi-temporal LiDAR data: The Portainé mountain catchment (Pyrenees)

Multi-temporal digital elevation models (DEMs) obtained from airborne LiDAR surveys are widely used to detect geomorphic changes in time and quantify sediment budgets. However, they have been rarely applied to study the geomorphic impact of engineering structures in mountain settings. In this study, we assessed the influence and behavior of flexible sediment retention barriers in the Portainé catchment (Spanish Pyrenees), using three LiDAR data sets (2009, 2011 and 2016) that covered a 7-year period. Densely forested mountainous areas present some limitations for reliable DEM analysis due to spatial variabilities in data precision, accuracy and point density. A new methodological approach for robust uncertainty analysis along channels, based on changes in cross-sectional elevations, was used to discriminate noise from real geomorphic changes. The obtained results indicated that erosion occurs along most reaches covering a large area, whereas deposition is localized in specific areas such as those upstream of sediment retention barriers and in the debris cone. Despite the presence of 15 flexible sediment retention barriers, the channels presented net degradation during both 2009-2011 and 2011-2016, with 2838 and 147m3 of material exported from the basin, respectively. For the same periods, the barriers retained 33% and 25% of the total deposition (up to 1300m3 per barrier), respectively, but also induced lateral and downstream incision, the latter reaching 703m3 for a single barrier. We detected a horizontal displacement of the net of up to 1.2m in filled barriers, resulting from net flexion. The interference of the natural river evolution by defense measures has resulted in a complex erosion-deposition pattern. The presented methods show high potential for the hydrogeomorphic study of mountain catchments, especially for a high-resolution assessment of flexible barriers or other engineering structures in remote areas

Fragmented host distribution and trombiculid parasitic load: Eutrombicula araucanensis and Liolaemus pictus in Chile

International audienceHabitat fragmentation produced by human impacts can generate changes in the distribution and abundance of populations across their geographic ranges. The chigger mites are ectoparasites that are widely distributed on a wide range of species. The distribution depends of the characteristics of the host and of the habitat where said species is found. As the host distribution is highly dependent on environmental factors, chigger mites are good study models to test geographical distribution patterns. The main objective of this study was to determine variation in abundance of Eutrombicula araucanensis, parasite on Liolaemus pictus, by testing three hypotheses: abundant centre hypothesis, abundance optimum hypothesis and latitudinal distribution pattern. For this purpose, mites from 147 individuals from 23 localities along the distribution of L. pictus were extracted. The three distribution models evaluated in the present study were not adequate to represent the geographical structure of parasitic mites on L. pictus. No association between the distance from the area of greatest species abundance and relative intensity, or association with the distance to the mite’s distribution centre was observed. In addition, no latitudinal distribution pattern was observed. Temperate forest fragmentation may influence the population density of mites, with each forest patch having different optimal conditions for development. The heterogeneity makes it difficult to find a clear distribution pattern

Dendrogeomorphological evidence of flood frequency changes and human activities (Portainé basin, spanish Pyrenees)

The Portainé mountain catchment, containing the Port Ainé ski resort (Lleida, Spanish Pyrenees), displays active erosional and depositional phenomena caused by periodic torrential floods. These events present a potential risk and incur significant economic losses. In ungauged remote catchments (like Portainé), trees might be the only paleohydrological source of information regarding past floods. Thus, we estimated the temporal and spatial distribution of torrential floods by dendrogeomorphological techniques to assess whether human impact (land-use changes and infrastructure works) affected their frequency and magnitude. One-hundred and sixty-six samples from 67 trees belonging to 10 different species were analyzed; past flood events of the last 50 years were identified by dating and relating evidence between them. Moreover, a detailed geomorphological study was performed and the available historical data compiled. Our multi-evidence analysis provides new insight into the occurrence of paleofloods. Changes in flood frequency since 2006, especially from 2008, suggest that the geomorphological equilibrium has been disturbed, coinciding with both major earthworks within the ski resort and intense but not extraordinary rainfall. This conclusion has important implications for land planning and the design of future projects in the mountain watersheds

Growth and yield of tomato crop under subsurface drip irrigation treated with different Trifluralin doses

[SPA] El trabajo pretende evaluar el crecimiento y rendimiento de un cultivo de tomate atendiendo al tipo del sistema de riego localizado: subterráneo (SDI) y superficial (CDI), sustrato y dosis y modo de aplicación de Trifluralina (TFN).Este trabajo consta de dos partes: la primera compara ambos sistemas de riego, evaluando la acción de TFN y su eficacia en la prevención de la intrusión radicular. Los resultados mostraron que SDI con una dosis apropiada de TFN generó mayor producción que CDI. La segunda parte evaluó la implicación de diferentes tipos de substratos, dosis de TFN y método de aplicación de TFN sobre el rendimiento y crecimiento de un cultivo de tomate bajo SDI. Los resultados sugieren que el incremento en la dosis de TFN previene la intrusión radicular pero reduce el potencial productivo del cultivo. Este hecho fue mayor en suelos con baja capacidad de retención de agua y TFN, donde el riesgo de intrusión radicular es reducido, por lo que dosis altas de TFN tiene una acción nociva sobre la producción. [ENG] The study evaluates the influence of the irrigation system, the soil substrate, the dosage and application of the herbicide trifluralin (TFN) in the growth and yield of tomato crops. This work comprised two differentiated parts. The first compares both systems irrigation, evaluating TFN action and its efficacy preventing from root intrusion. Results showed that SDI with an appropriate dosage of TFN to prevent from root intrusion, yielded higher production that CDI. The second part assessed the implication of different soil substrates, TFN dosage and application method in the yield and growth of tomato crops under SDI. Results suggested that an increasing dose of TFN prevents drippers from root intrusion but reduced crop productivity. This fact was enhanced in soils with low water retention capacity (sand), where the risk of root intrusion was lower, so high doses of TFN had a harmful rather than a beneficial effect on crop production.Trabajo financiado por el Proyecto de Investigación “Desarrollo técnico y agronómico del riego localizado subterráneo como alternativa para aumentar la eficiencia hídrica en diferentes sistemas agrícolas. 480/02PA” entre la UPCT y Sistema Azud S. A