Diseño de un sistema de información para la gestión del mantenimiento en maderas Venturelli y Cía. Ltda

210 p.El presente proyecto de memoria tiene como objetivo general el análisis y diseño de un sistema de información para el mantenimiento en la empresa Maderas Venturelli y Cía. Ltda., en la actualidad esta organización carece de actividades sistemáticas, definidas y programadas para la ejecución de las tareas de mantenimiento tanto para sus equipos como instalaciones asociadas a su proceso productivo.En base a los anterior es que se realizó un análisis situacional respecto a la forma de cómo se están ejecutando las labores de mantenimiento, lo cual se basó en la aplicación de una auditoría interna para cada uno de los procedimientos asociados a las distintas actividades de mantenimiento desarrolladas, en cada una de las áreas que componen la empresa y que inciden de una u otra forma en este procedimiento. Dicho análisis permitió identificar las principales falencias que posee el departamento, las cuales sirvieron como base para desarrollar e identificar las principales necesidades que posee el departamento, utilizando una metodología que capta los conocimiento y experiencia del encargado de esta área, denominada Metodología Multicriterio de Apoyo a las Decisiones Constructivistas (MCDA Constructivista). La Metodología MCDA constructivista, permitió identificar la necesidad de diseñar un sistema de información para el mantenimiento documentado que establezca las políticas y lineamientos generales al departamento de mantenimiento, respecto de la forma correcta de planificar, dirigir, ejecutar, controlar, registrar la ejecución de las tareas de mantenimiento.El desarrollo de este sistema aportará una base de datos tendiente a apoyar la gestión del encargado de mantenimiento, referente a información tales como Costo, insumos, herramientas y mano de obra utilizada, así como también generar un análisis estadístico a partir de registro de fallas

Do no-till and pig slurry application improve barley yield and water and nitrogen use efficiencies in rainfed Mediterranean conditions?

Tillage and N fertilization strategies including mineral and organic sources need to be studied in combination given their importance on the production cost that farmers face and their potential interaction on crop performance. A four-year (2010–2014) experiment based on barley monocropping was carried out in NE Spain in a typical rainfed Mediterranean area. Two tillage treatments (CT, conventional tillage; NT, no-tillage) and three rates of N fertilization (0; 75 kg N ha−1, applied at top-dressing; 150 kg N ha−1, applied at pre-sowing and at top-dressing at equal rate), with two types of fertilizers (ammonium-based mineral fertilizer and organic fertilizer with pig slurry), were compared in a randomized block design with three replications. Different soil (water and nitrate contents) and crop (above-ground biomass, grain yield, yield components and N concentration in biomass and grain) measurements were performed. Water- and nitrogen use efficiencies (WUE and NUE) as well as other N-related indexes (grain and above-ground biomass N uptake; NHI, nitrogen harvest index; NAR, apparent nitrogen recovery efficiency) were calculated. Barley above-ground biomass and grain yield were highly variable and depended on the rainfall received on each cropping season (ranging between 280 mm and 537 mm). Tillage and N fertilization treatments affected barley grain yields. No-tillage showed 1.0, 1.7 and 6.3 times greater grain yield than CT in three of the four cropping seasons as a result of the greater soil water storage until tillering. Water scarcity during the definition of the number of spikes per m2 under CT would have compromised the compensation mechanism of the other two yield components. Pig slurry application led to the same (3 of 4 years) or higher (1 of 4 years) grain yield than an equivalent rate of mineral N fertilizer. Regardless the N origin, barley yield did not respond to the application of 150 kg N ha−1 split between pre-sowing and top-dressing compared to the 75 kg N ha−1 rate applied as top-dressing. A significant nitrate accumulation in the soil over the experimental period was observed under CT. Greater barley water use efficiency for yield (WUEy), N uptake and grain N content were found under NT than CT in three of the four cropping seasons studied. Moreover, for a given N rate, the use of organic fertilization increased significantly the WUEy as an average of CT and NT. When CT was used, a greater NHI was observed when using pig slurry compared with mineral N as an average of the four years studied. However, the use of different N fertilization treatments (rates or types) under CT or NT did not increase the NUE compared with the control. Our study demonstrates that the use of NT and the application of agronomic rates of N as pig slurry leads to greater barley yield and water- and nitrogen-use efficiencies than the traditional management based on CT and mineral N fertilization.We thank Silvia Martí, Carlos Cortés, Ana Bielsa, Maria José Salvador, Josan Palacio and Héctor Martínez for their technical assistance. Daniel Plaza-Bonilla received a Juan de la Cierva Postdoctoral Grant from the Ministerio de Economía y Competitividad of Spain. This research was supported by the Ministerio de Economía y Competitividad of Spain (grants AGL2007-66320-C02-01, AGL2010-22050-C03-01/02 and AGL2013-49062-C4). This paper has been produced within the context of the Red SIRENA network (Ref. AGL2015-68881-REDT) funded by the Ministerio de Economía y Competitividad of Spain

Pig slurry incorporation with tillage does not reduce short-term soil CO2 fluxes

Tillage and organic fertilization impact short-term soil CO2 fluxes. However, the interactive effect of these two management practices has been rarely studied under field conditions. The objective of this study was to evaluate the impact of tillage (NT, no-tillage, and CT, conventional tillage) and fertilization strategy (PS, pig slurry, and MF, mineral fertilizer) on short-term soil CO2 fluxes in a rainfed Mediterranean agroecosystem. Soil CO2 fluxes were measured several times during two tillage and pre-sowing fertilization periods in 2012 and 2013 (7 and 6 times in 2012 and 2013, respectively). In the two years studied, tillage and fertilization significantly affected soil CO2 fluxes, but the interaction between both factors was not significant. The application of PS resulted in a sharp and immediate increase in the soil CO2 flux. One hour after the application of the organic fertilizer, soil CO2 emissions increased from 0.05 to 0.70 g CO2 m−2 h−1 and from 0.08 to 0.82 g CO2 m−2 h−1 in 2012 and 2013, respectively. Unlike fertilization, 1 h after tillage similar soil CO2 fluxes were observed in CT and NT plots. However, after 7 h, larger fluxes were observed in CT compared with NT in both years. Cumulative CO2 flux during the first 24 h after fertilization and tillage was about three- and two-fold greater in PS than in MF and in CT than in NT, respectively. The results of this study showed that in rainfed Mediterranean systems, soil management and fertilization have a noteworthy impact on short-term soil CO2 losses though no interactive effects were observed between both management practices.This research was supported by the Ministry of Economy and Competitiveness of Spain (AGL2010-22050-C03-01/02; AGL2013-49062- C4-4-R) and the COMET-Global project (FACCE-JPI grant)

Simulating climate change and land use effects on soil nitrous oxide emissions in Mediterranean conditions using the Daycent model

In Mediterranean agroecosystems, limited information exists about possible impacts of climate change on soil N2O emissions under different land uses. This paper presents a modelling study with a dual objective. Firstly, the biogeochemical Daycent model was evaluated to predict soil N2O emissions in different land uses in a typical Mediterranean agroecosystem. Secondly, the study aimed to determine the impact of climate change on soil N2O emissions in different Mediterranean land uses over an 85-year period. Soil N2O emissions were measured in three land uses (cropland, abandoned land and afforested land) over 18 months (December 2011 to June 2013) in a characteristic Mediterranean site in Spain. For climate change simulations, Daycent was run with and without atmospheric CO2 enrichment using climate data from the CGCM2-A2 model. The cumulative N2O emissions predicted by the Daycent model agreed well with the observed values. The lack of fit (LOFIT) and the relative error (E) statistics determined that the model error was not greater than the error in the measurements and that the bias in the simulation values was lower than the 95% confidence interval of the measurements. For the different land uses and climate scenarios, annual cumulative N2O emissions ranged from 126 to 642 g N2O-N ha−1 yr−1. Over the simulated 85-year period, climate change decreased soil N2O emissions in all three land uses. At the same time, under climate change, water filled pore space (WFPS) values decreased between 4% and 15% depending on the land use and climate change scenario considered. This study demonstrated the ability of the Daycent model to simulate soil N2O emissions in different land uses. According to model predictions, in Mediterranean conditions, climate change would lead to reduced N2O emissions in a range of land uses.Jorge Álvaro-Fuentes acknowledges the receipt of a fellowship from the OECD Co-operative Research Programme: Biological Resource Management in Sustainable Agricultural Systems in 2013. Daniel Plaza-Bonilla received a “Juan de la Cierva” grant from the Ministerio de Economía y Competitividad of Spain. This study was also possible through funds provided by the Aragon Regional Government and La Caixa (grant GA-LC-050/2011), the Ministry of Economy and Competitiveness of Spain (grant AGL2013-49062-C4-4-R) and the COMET-Global project (FACCE-JPI grant). We are grateful to María José Salvador and Javier Bareche for laboratory assistance

Beneficios agroambientales de la reducción del laboreo en los secanos semiáridos del valle del Ebro

10 Pags.- 3 Tabls.- 3 Figs.[ES] Después de analizar la tendencia actual al aumento de la superficie cultivada con siembra directa o no laboreo y al descenso de la superficie total de barbecho y la del barbecho mantenido con laboreo tradicional, se presenta una síntesis de los resultados obtenidos en las últimas dos décadas sobre los beneficios derivados de la reducción del laboreo, a través de la adopción de técnicas de agricultura de conservación (laboreo reducido y no laboreo) y su influencia en algunos parámetros edáficos, agronómicos y medioambientales en los sistemas de cultivo de secano semiárido del Valle del Ebro. La conclusión es evidente. El uso de dichas técnicas, especialmente el no laboreo, como alternativa al laboreo intensivo tradicional, es una estrategia recomendable para mejorar tanto la calidad y productividad del suelo como la conservación y sostenibilidad de dichos agrosistemas.[EN] In the context of the current nationwide trend towards the increase in the proportion of cultivated land with no tillage and the decrease of total fallowed land area including that of traditional tilled fallow, the authors overview selected results obtained during the last two decades on the beneficial influence of conservation agriculture practices (reduced tillage and no-tillage) in soil, agronomic and environmental parameters in semiarid dryland farming systems of the River Ebro Valley. In the light of the results presented, it becomes evident that adopting conservation tillage technologies, especially no-tillage, is a viable alternative to conventional tillage for improving not only soil quality and productivity but also the conservation and sustainability of those agricultural systems.Peer reviewe

Soil Aggregation and Soil Organic Carbon Stabilization: Effects of Management in Semiarid Mediterranean Agroecosystems

In semiarid agroecosystems of the Ebro valley (NE Spain) soils are characterized by low soil organic matter (SOM) and a weak structure. In this study we investigated the individual and combined effect of tillage system (no-tillage, NT; reduced tillage, RT; conventional tillage, CT) and cropping system (barley–fallow rotation at the Peñaflor site, PN-BF and continuous barley at the Peñaflor site, PN-BB) on soil organic carbon (SOC) storage as well as the physical protection of SOM fractions by soil aggregates in three long-term experimental sites. In both cropping systems, total SOC content was more than 30% higher in NT compared with CT in the 0- to 5-cm depth. The suppression of fallowing in the PN-BB cropping system led to a greater SOC stabilization only in NT. In all the three sites, greater proportion of water-stable macroaggregates (>250 µm) was found under NT than under CT in the 0- to 5-cm depth. Macroaggregate organic C concentration (250–2000 µm) was greater in NT compared with CT in the BB cropping system, but did not differ with tillage treatment in the PN-BF rotation. Greater proportion of microaggregates within macroaggregates in NT compared with CT was only found in the Agramunt site (AG). However, greater C stabilized inside these microaggregates was observed in AG, Selvanera site (SV), and PN-BB in the 0- to 5-cm depth. The results of this study demonstrate that in the semiarid Mediterranean agroecosystems of the Ebro valley, the adoption of NT together with the suppression of long-fallowing period can significantly increase the amount of SOC stabilized in the soil surface and improve soil structure and aggregation.This research was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain (Grants AGL2001-2238-CO2-01, AGL 2004-07763-C02-02 and AGL2007-66320-CO2-02/AGR) and the European Union (FEDER funds).Peer reviewe