How do various maize crop models vary in their responses to climate change factors?

Comments This article is a U.S. government work, and is not subject to copyright in the United States. Abstract Potential consequences of climate change on crop production can be studied using mechanistic crop simulation models. While a broad variety of maize simulation models exist, it is not known whether different models diverge on grain yield responses to changes in climatic factors, or whether they agree in their general trends related to phenology, growth, and yield. With the goal of analyzing the sensitivity of simulated yields to changes in temperature and atmospheric carbon dioxide concentrations [CO2], we present the largest maize crop model intercomparison to date, including 23 different models. These models were evaluated for four locations representing a wide range of maize production conditions in the world: Lusignan (France), Ames (USA), Rio Verde (Brazil) and Morogoro (Tanzania). While individual models differed considerably in absolute yield simulation at the four sites, an ensemble of a minimum number of models was able to simulate absolute yields accurately at the four sites even with low data for calibration, thus suggesting that using an ensemble of models has merit. Temperature increase had strong negative influence on modeled yield response of roughly 0.5 Mg ha 1 per °C. Doubling [CO2] from 360 to 720 lmol mol 1 increased grain yield by 7.5% on average across models and the sites. That would therefore make temperature the main factor altering maize yields at the end of this century. Furthermore, there was a large uncertainty in the yield response to [CO2] among models. Model responses to temperature and [CO2] did not differ whether models were simulated with low calibration information or, simulated with high level of calibration information.

Replacing bare fallow with cover crops in an irrigated cropping system: soil salinity and salt leaching

In irrigated areas where cover crop establishment can be assured, consequent soil or nutrient conservation could increase sustainability of cropping systems. Replacing bare fallow with cover crops may increase sustainability by enhancing soil aggregate stability, water retention capacity or controlling nitrate leaching. Nevertheless, adoption of cover crops increase evapotranspiration and reduce water percolation beyond the root systems; therefore, it could lead to salt accumulation in the upper soil layers. This study was conducted during four years to determine the effect of replacing bare fallow by a cover crop on soil salt accumulation and salt leaching in an irrigated maize production system.

Paisajes de la sal en Andalucía

Los paisajes protagonistas de esta investigación han sido creados gracias a la actividad de las salinas, explotaciones “donde se beneficia la sal de las aguas del mar o de ciertos manantiales, cuando se ha evaporado el agua.” (RAE). Son lugares de características únicas, tanto por sus valores naturales y medioambientales, como por los valores culturales, patrimoniales, históricos, sociales e identitarios, “resultado de la acción e interacción de factores naturales y humanos en el territorio” (CEP, 2000). Existen salinas en muchos lugares del mundo, pero es en la Península Ibérica donde se encuentra la mayor concentración de estas explotaciones en toda Europa y, por consiguiente, de los singulares paisajes asociados y generados por ellas. Es también la única región europea donde existen salinas de interior que utilizan métodos de evaporación para la obtención de sal: las energías y circunstancias naturales aprovechadas en ellas, sol, viento, gravedad y humedad relativa, propician la evaporación del agua salada, una de las estrategias fundamentales para su funcionamiento. Esta circunstancia determina su posición geográfica en el territorio y su dependencia de los ciclos climáticos estacionales, del régimen hidrológico, la estructura geológica del subsuelo, la geomorfología y la acción humana para potenciar la eficiencia de los procesos productivos, creando para ello un extenso e interesante patrimonio natural y cultural en torno a ellas. Por tanto, son también paisajes culturales, resultado de un proceso artesanal de producción y comercialización de la sal, que se articula a través de la construcción de una serie de instalaciones preindustriales diseminadas y conectadas en puntos estratégicos del territorio costero e interior. La presente tesis aborda la grave situación a la que se enfrentan en la actualidad los paisajes ibéricos de la sal, concretamente los ubicados en la Comunidad Autónoma de Andalucía, que están sufriendo un ávido proceso de abandono y desaparición desde mediados del s. XX, con la consiguiente pérdida para la sociedad de este valioso patrimonio cultural y natural, que se ha ido construyendo durante siglos, prácticamente desde el inicio de la humanidad. De las diversas tipologías de salinas que existen, se han seleccionado las explotaciones, tanto marítimas como de interior, que utilizan o han utilizado en su origen técnicas de explotación artesanal basadas en la evaporación. El interés de esta acotación tipológica se ha basado en las relaciones de dependencia que estas explotaciones de sal establecen con el entorno físico y climático donde se ubican para poder existir y funcionar. El objetivo principal de esta investigación ha perseguido el establecimiento y definición de un marco territorial, global e integrador, para los paisajes culturales salineros andaluces, a través de la observación directa realizada durante el trabajo de campo, el análisis de textos, imágenes, documentos, gráficos, palabras y entrevistas abiertas. Lo anterior ha permitido identificar, clasificar, analizar y valorar sus principales características y su evolución en el tiempo, identificando las causas del deterioro y desaparición del patrimonio salinero, evaluando la efectividad de las iniciativas, públicas y/o privadas, y de las figuras de protección, así como analizar las relaciones que establecen con su entorno próximo, con los núcleos de población y habitantes a los que sirven, la red de carreteas y caminos que las conectan y los ríos y mares que las proveen de materia prima. Finalmente, se ha establecido una sistemática integral de análisis, con el fin de poder actuar, a partir del conocimiento, a favor de la gestión, salvaguarda y pervivencia de los excepcionales valores culturales y naturales, que definen el carácter e identidad de estos singulares paisajes. ----------------------ABSTRACT----------------- The landscapes of this research have been created by the activity of saltworks, sites “where salt from sea water or certain springs is obtained, when water evaporates.” (RAE). They are places with unique characteristics, because of their natural and environmental values, as well as their cultural, historic and social values, their heritage and identity, “the result of the action and interaction of natural and human factors on the territory” (European Landscape Convention, 2000). There are many saltworks in many places around the world, but it is in the Iberian Peninsula where we find the highest concentration of salt industries within Europe and, therefore, the particular landscapes associated and created by them. It is as well the only European region where we can find inland saltworks with evaporation methods to obtain salt: the energies and natural circumstances used in them are sun, wind, gravity and relative humidity, favouring salt water evaporation, one of the main strategies of their functioning. This circumstance determines their geographic position in the territory and its dependence on seasonal climatic cycles, hydrological regimes, geological subsoil structure, geomorphology and human action to strengthen productive processes efficiency, creating an extensive and interesting natural and cultural heritage around them. Therefore, they are also cultural landscapes, result of a traditional salt production process and marketing, organized through the construction of certain preindustrial buildings scattered and connected in strategic inland and seaside spots. This thesis deals with the plight today’s salt landscapes are facing, particularly those within the Andalucian Region, since the middle of the 20th century undergoing an avid process of abandonment and disappearance, meaning a great loss for society of a cultural and natural heritage constructed along centuries, almost since the beginning of mankind. Among the diverse typologies of saltworks, the selection made consists on those inland and seaside ones, which use or have originally used traditional production techniques based on evaporation. The interest in this particular saltwork typology is based on the dependency relationships these industries establish with the environment and climate where they are located, in order to be able to exist and function. The main goal of this research has pursued to establish and define a global and inclusive territorial framework for Andalucian cultural saltworks landscapes, through direct observation carried out during fieldwork, analysis of texts, images, documents, graphs, words and open interviews. All of it has allowed to identify, classify, analyze and evaluate their main characteristics and evolution over time, identifying the causes of deterioration and disappearance of the saltworks heritage, assessing the effectiveness of public and private initiatives, and protection projects, as well as analyzing the relationships with their surroundings, population centers and residents they serve, road networks connecting them and rivers and seas supplying the raw material. Finally, a comprehensive analysis systematic has been established, in order to be able to take action, with knowledge as starting point, for the management, preservation and survival of the unique cultural and natural values that define the character and identity of these singular landscapes.

Paisajes de la sal en Andalucía

Los paisajes protagonistas de esta investigación han sido creados gracias a la actividad de las salinas, explotaciones “donde se beneficia la sal de las aguas del mar o de ciertos manantiales, cuando se ha evaporado el agua.” (RAE). Son lugares de características únicas, tanto por sus valores naturales y medioambientales, como por los valores culturales, patrimoniales, históricos, sociales e identitarios, “resultado de la acción e interacción de factores naturales y humanos en el territorio” (CEP, 2000). Existen salinas en muchos lugares del mundo, pero es en la Península Ibérica donde se encuentra la mayor concentración de estas explotaciones en toda Europa y, por consiguiente, de los singulares paisajes asociados y generados por ellas. Es también la única región europea donde existen salinas de interior que utilizan métodos de evaporación para la obtención de sal: las energías y circunstancias naturales aprovechadas en ellas, sol, viento, gravedad y humedad relativa, propician la evaporación del agua salada, una de las estrategias fundamentales para su funcionamiento. Esta circunstancia determina su posición geográfica en el territorio y su dependencia de los ciclos climáticos estacionales, del régimen hidrológico, la estructura geológica del subsuelo, la geomorfología y la acción humana para potenciar la eficiencia de los procesos productivos, creando para ello un extenso e interesante patrimonio natural y cultural en torno a ellas. Por tanto, son también paisajes culturales, resultado de un proceso artesanal de producción y comercialización de la sal, que se articula a través de la construcción de una serie de instalaciones preindustriales diseminadas y conectadas en puntos estratégicos del territorio costero e interior. La presente tesis aborda la grave situación a la que se enfrentan en la actualidad los paisajes ibéricos de la sal, concretamente los ubicados en la Comunidad Autónoma de Andalucía, que están sufriendo un ávido proceso de abandono y desaparición desde mediados del s. XX, con la consiguiente pérdida para la sociedad de este valioso patrimonio cultural y natural, que se ha ido construyendo durante siglos, prácticamente desde el inicio de la humanidad. De las diversas tipologías de salinas que existen, se han seleccionado las explotaciones, tanto marítimas como de interior, que utilizan o han utilizado en su origen técnicas de explotación artesanal basadas en la evaporación. El interés de esta acotación tipológica se ha basado en las relaciones de dependencia que estas explotaciones de sal establecen con el entorno físico y climático donde se ubican para poder existir y funcionar. El objetivo principal de esta investigación ha perseguido el establecimiento y definición de un marco territorial, global e integrador, para los paisajes culturales salineros andaluces, a través de la observación directa realizada durante el trabajo de campo, el análisis de textos, imágenes, documentos, gráficos, palabras y entrevistas abiertas. Lo anterior ha permitido identificar, clasificar, analizar y valorar sus principales características y su evolución en el tiempo, identificando las causas del deterioro y desaparición del patrimonio salinero, evaluando la efectividad de las iniciativas, públicas y/o privadas, y de las figuras de protección, así como analizar las relaciones que establecen con su entorno próximo, con los núcleos de población y habitantes a los que sirven, la red de carreteas y caminos que las conectan y los ríos y mares que las proveen de materia prima. Finalmente, se ha establecido una sistemática integral de análisis, con el fin de poder actuar, a partir del conocimiento, a favor de la gestión, salvaguarda y pervivencia de los excepcionales valores culturales y naturales, que definen el carácter e identidad de estos singulares paisajes. ----------------------ABSTRACT----------------- The landscapes of this research have been created by the activity of saltworks, sites “where salt from sea water or certain springs is obtained, when water evaporates.” (RAE). They are places with unique characteristics, because of their natural and environmental values, as well as their cultural, historic and social values, their heritage and identity, “the result of the action and interaction of natural and human factors on the territory” (European Landscape Convention, 2000). There are many saltworks in many places around the world, but it is in the Iberian Peninsula where we find the highest concentration of salt industries within Europe and, therefore, the particular landscapes associated and created by them. It is as well the only European region where we can find inland saltworks with evaporation methods to obtain salt: the energies and natural circumstances used in them are sun, wind, gravity and relative humidity, favouring salt water evaporation, one of the main strategies of their functioning. This circumstance determines their geographic position in the territory and its dependence on seasonal climatic cycles, hydrological regimes, geological subsoil structure, geomorphology and human action to strengthen productive processes efficiency, creating an extensive and interesting natural and cultural heritage around them. Therefore, they are also cultural landscapes, result of a traditional salt production process and marketing, organized through the construction of certain preindustrial buildings scattered and connected in strategic inland and seaside spots. This thesis deals with the plight today’s salt landscapes are facing, particularly those within the Andalucian Region, since the middle of the 20th century undergoing an avid process of abandonment and disappearance, meaning a great loss for society of a cultural and natural heritage constructed along centuries, almost since the beginning of mankind. Among the diverse typologies of saltworks, the selection made consists on those inland and seaside ones, which use or have originally used traditional production techniques based on evaporation. The interest in this particular saltwork typology is based on the dependency relationships these industries establish with the environment and climate where they are located, in order to be able to exist and function. The main goal of this research has pursued to establish and define a global and inclusive territorial framework for Andalucian cultural saltworks landscapes, through direct observation carried out during fieldwork, analysis of texts, images, documents, graphs, words and open interviews. All of it has allowed to identify, classify, analyze and evaluate their main characteristics and evolution over time, identifying the causes of deterioration and disappearance of the saltworks heritage, assessing the effectiveness of public and private initiatives, and protection projects, as well as analyzing the relationships with their surroundings, population centers and residents they serve, road networks connecting them and rivers and seas supplying the raw material. Finally, a comprehensive analysis systematic has been established, in order to be able to take action, with knowledge as starting point, for the management, preservation and survival of the unique cultural and natural values that define the character and identity of these singular landscapes.

Even-sowing pattern strategies for a low-input agricultural system in forage maize

The objective of this study was to verify the effectiveness of new patterns of sowing and to achieve a low-input organic system in two different environments (northern and southern Europe). The study was motivated by the hypothesis that more even sowing patterns (triangular and square) would significantly enhance the growth and yield of forage maize under widely varying conditions, compared with traditional mechanised rectangular seed patterns. An experiment was conducted in Madrid and duplicated in Copenhagen during 2010. A random block design was used with a 2 × 2 factorial arrangement based on two seed-sowing patterns: traditional (rectangular) and new (even) and two weed-management conditions (herbicide use and a low-input system). In both weed-management conditions and locations, the production of aerial maize biomass was greater for the new square seed patterns. In addition, the new pattern showed a greater effectiveness in the control of weeds, both at the initial crop stages (36 and 33% fewer weeds m-2 at the 4- and 8-leaf stages, respectively, in the Copenhagen field experiment) and at the final stage. The final weed biomass for the new pattern was 568 kg ha-1 lower for the Copenhagen experiment and 277 kg ha-1 lower in Madrid field experiments. In the light of these results, the new pattern could potentially reduce the use of herbicides. The results of the experiments support the hypothesis formulated at the beginning of this study that even-sowing patterns would be relatively favourable for the growth and yield of the maize crop. In the near future, new machinery could be used to achieve new seed patterns for the optimisation of biomass yield under low-input systems. This approach is effective because it promotes natural crop-weed competition.

Combine use of Selected Schizosaccharomyces pombe and Lachancea thermotolerans Yeast Strains as an Alternative to the Traditional Malolactic Fermentation in Red Wine Production

Most red wines commercialized in the market use the malolactic fermentationprocess in order to ensure stability from a microbiological point of view. In this secondfermentation, malic acid is converted into L-lactic acid under controlled setups. Howeverthis process is not free from possible collateral effects that on some occasions produceoff-flavors, wine quality loss and human health problems. In warm viticulture regions suchas the south of Spain, the risk of suffering a deviation during the malolactic fermentationprocess increases due to the high must pH. This contributes to produce wines with highvolatile acidity and biogenic amine values. This manuscript develops a new red winemakingmethodology that consists of combining the use of two non-Saccharomyces yeast strains asan alternative to the traditional malolactic fermentation. In this method, malic acid is totallyconsumed by Schizosaccharomyces pombe, thus achieving the microbiological stabilizationobjective, while Lachancea thermotolerans produces lactic acid in order not to reduce andeven increase the acidity of wines produced from low acidity musts. This technique reducesthe risks inherent to the malolactic fermentation process when performed in warm regions.The result is more fruity wines that contain less acetic acid and biogenic amines than thetraditional controls that have undergone the classical malolactic fermentation.

Climate Change Impacts on Maize and Dry Bean Yields of smallholder farmers in Honduras

The rotation maize and dry bean provides the main food supply of smallholder farmers in Honduras. Crop model assessment of climate change impacts (2070?2099 compared to a 1961?1990 baseline) on a maize?dry bean rotation for several sites across a range of climatic zones and elevations in Honduras. Low productivity systems, together with an uncertain future climate, pose a high level of risk for food security. The cropping systems simulation dynamic model CropSyst was calibrated and validated upon field trail site at Zamorano, then run with baseline and future climate scenarios based upon general circulation models (GCM) and the ClimGen synthetic daily weather generator. Results indicate large uncertainty in crop production from various GCM simulations and future emissions scenarios, but generally reduced yields at low elevations by 0 % to 22 % in suitable areas for crop production and increased yield at the cooler, on the hillsides, where farming needs to reduce soil erosion with conservation techniques. Further studies are needed to investigate strategies to reduce impacts and to explore adaptation tactics.

Integrated learning of production engineering software applications in a shipbuilding context

Acourse focused on the acquisition of integration competencies in ship production engineering, organized in collaboration with selected industry partners, is presented in this paper. The first part of the course is dedicated to Project Management: the students acquire skills in defining, using MS-PROJECT, the work breakdown structure (WBS), and the organization breakdown structure (OBS) in Engineering projects, through a series of examples of increasing complexity with the final one being the construction planning of a vessel. The second part of the course is dedicated to the use of a database manager, MS-ACCESS, in managing production related information.Aseries of increasing complexity examples is treated, the final one being the management of the piping database of a real vessel. This database consists of several thousand pipes, for which a production timing frame is defined connecting this part of the course with the first one. Finally, the third part of the course is devoted to working withFORAN,an Engineering Production application developed bySENERand widely used in the shipbuilding industry. With this application, the structural elements where all the outfittings will be located are defined through cooperative work by the students, working simultaneously in the same 3D model. In this paper, specific details about the learning process are given. Surveys have been posed to the students in order to get feedback from their experience as well as to assess their satisfaction with the learning process, compared to more traditional ones. Results from these surveys are discussed in the paper.

Genetic characterization of chestnut (Castanea sativa Mill.) orchards and traditional nut varieties in El Bierzo, a glacial refuge and major cultivation site in Northwestern Spain

This paper presents a detailed genetic study of Castanea sativa in El Bierzo, a major nut production region with interesting features. It is located within a glacial refuge at one extreme of the distribution area (northwest Spain); it has a centenary tradition of chestnut management; and more importantly, it shows an unusual degree of genetic isolation. Seven nuclear microsatellite markers were selected to analyze the genetic variability and structure of 169 local trees grafted for nut production. We analyzed in the same manner 62 local nuts. The selected loci were highly discriminant for the genotypes studied, giving a combined probability of identity of 6.1 × 10−6. An unprecedented density of trees was sampled for this project over the entire region, and nuts were collected representing 18 cultivars marketed by local producers. Several instances of misclassification by local growers were detected. Fixation index estimates and analysis of molecular variance (AMOVA) data are supportive of an unexpectedly high level of genetic differentiation in El Bierzo, larger than that estimated in a previous study with broader geographical scope but based on limited local sampling (Pereira-Lorenzo et al., Tree Genet Genomes 6: 701–715, 2010a). Likewise, we have determined that clonality due to grafting had been previously overestimated. In line with these observations, no significant spatial structure was found using both a model-based Bayesian procedure and Mantel’s tests. Taken together, our results evidence the need for more fine-scale genetic studies if conservation strategies are to be efficiently improved.

Type of grinding of the main cereal of the diet affects production of brown egg-laying hens

The influence of method of grinding of the cereal of the diet on production and egg quality was studied in 420 Hy-line brown egg-laying hens. The design was completely randomized with six treatments arranged as a 3 × 2 factorial with three cereals (barley, dented maize and soft wheat) and two grinding procedures (hammer mill vs. roller mill). Each treatment was replicated seven times and the experimental unit was an enriched cage with ten hens. Production was recorded every four weeks from 24 to 59 weeks of age and egg quality was measured at 40 and 56 weeks of age. For the entire experiment, feed intake was higher in hens fed wheat or maize than in hens fed barley (110.8 and 110.7 vs. 109.7 g/d; P = 0.014) but most of the differences were observed when the cereal was roller milled (P = 0.009 for the interaction). Also, egg production was similar for the three diets when the cereal was hammer milled but tended to be lower for the barley than for the wheat or maize diets when the cereal was roller milled (P = 0.09 for the interaction). None of the other productive or egg quality traits was affected by dietary treatment. We conclude that roller mills are useful to grind low fiber cereals, such as maize or wheat. However, the use of the roller mill might not be adequate when barley is the main cereal in diets for egg-laying hens.

El Niño influence on potential maize yield in Iberian Peninsula

El Niño phenomenon is the leading mode of sea surface temperature interannual variability. It can affect weather patterns worldwide and therefore crop production. Crop models are useful tools for impact and predictability applications, allowing to obtain long time series of potential and attainable crop yield, unlike to available time series of observed crop yield for many countries. Using this tool, crop yield variability in a location of Iberia Peninsula (IP) has been previously studied, finding predictability from Pacific El Niño conditions. Nevertheless, the work has not been done for an extended area. The present work carries out an analysis of maize yield variability in IP for the whole twenty century, using a calibrated crop model at five contrasting Spanish locations and reanalyses climate datasets to obtain long time series of potential yield. The study tests the use of reanalysis data for obtaining only climate dependent time series of crop yield for the whole region, and to use these yield to analyze the influences of oceanic and atmospheric patterns. The results show a good reliability of reanalysis data. The spatial distribution of the leading principal component of yield variability shows a similar behaviour over all the studied locations in the IP. The strong linear correlation between El Niño index and yield is remarkable, being this relation non-stationary on time, although the air temperature-yield relationship remains on time, being the highest influences during grain filling period. Regarding atmospheric patterns, the summer Scandinavian pattern has significant influence on yield in IP. The potential usefulness of this study is to apply the relationships found to improving crop forecasting in IP.