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Parmi les tout premiers bâtiments fouillés sur le site de Pompéi, entre 1771 et 1775, la Villa de Diomède constitue l'un des édifices les plus décrits et représentés par les voyageurs du Grand Tour. Engagé en 2012, un programme pluridisciplinaire a eu pour objectif de restituer toute son évolution, conjuguant la fabrique matérielle d'une villa romaine et sa fabrique imaginaire contemporaine. Il s'agissait d'identifier et de modéliser les différents chantiers de construction qui en ont transformé le bâtiment, de la fin du XVIIIe siècle à nos jours. Pour ce faire, différentes compétences se sont associées : histoire des fouilles et des restaurations, archéologie de la construction, bases de données, systèmes d'information géographique, géophysique, ingénierie des structures, imagerie scientifique et modélisation 3D. Les trente-trois contributions réunies rendent compte de ces regards croisés sur l'entière fabrique de cette villa singulière, envisagée sur la longue durée.

In a previous work, the spatial and temporal wind effects on corn yield were analysed using Ador-Crop (based onthe FAO crop model CropWat) and a solid set sprinkler irrigation model. The combined model could explain only 25% of the variability of measured yield. The objective of this work was to evaluate the predictive capacity of two more advanced crop models (EPICphase and DSSAT) when coupled to the solid set sprinkler irrigation model. EPICphase explained 44% of total dry mater (TDM) and grain yield (GY) variability when measured irrigation was used. The combination of EPICphase and the solid set sprinkler irrigation model explained better the variability of TDM than that of GY (42% and 35%, respectively), although the error in the estimation of GY with the coupled model was higher than when measured irrigation doses were considered (1.55 t ha the FAO crop model CropWat) and a solid set sprinkler irrigation model. The combined model could explain only 25% of the variability of measured yield. The objective of this work was to evaluate the predictive capacity of two more advanced crop models (EPICphase and DSSAT) when coupled to the solid set sprinkler irrigation model. EPICphase explained 44% of total dry mater (TDM) and grain yield (GY) variability when measured irrigation was used. The combination of EPICphase and the solid set sprinkler irrigation model explained better the variability of TDM than that of GY (42% and 35%, respectively), although the error in the estimation of GY with the coupled model was higher than when measured irrigation doses were considered (1.55 t ha the FAO crop model CropWat) and a solid set sprinkler irrigation model. The combined model could explain only 25% of the variability of measured yield. The objective of this work was to evaluate the predictive capacity of two more advanced crop models (EPICphase and DSSAT) when coupled to the solid set sprinkler irrigation model. EPICphase explained 44% of total dry mater (TDM) and grain yield (GY) variability when measured irrigation was used. The combination of EPICphase and the solid set sprinkler irrigation model explained better the variability of TDM than that of GY (42% and 35%, respectively), although the error in the estimation of GY with the coupled model was higher than when measured irrigation doses were considered (1.55 t ha–1 vs. 1.22 t ha–1). The DSSAT model explained 39% and 38% of the variability in TDM and GY, respectively, when measured irrigation data was used. When DSSAT was considered in the coupled model, better results were obtained for TDM (R2 = 41%) than GY (R2 = 31%). The EPICphase model simulated grain yield more accurately than the DSSAT model because it produced a better prediction of the maximum LAI. The combination of the sprinkler irrigation model with the EPICphase or DSSAT models simulated crop growth and yield more accurately than when combined with the Ador-Crop model., En trabajos anteriores se ha estudiado el efecto espacial y temporal del viento sobre el rendimiento del cultivo de maíz utilizando el modelo Ador-Crop (basado en el modelo de FAO CropWat) y un modelo de simulación de la distribución del agua de riego por aspersión en cobertura total. El modelo combinado pudo explicar sólo el 25% de la variabilidad de la reducción de rendimiento medida. El objetivo de este trabajo fue estimar la capacidad predictiva de dos modelos de cultivo más avanzados (EPICphase y DSSAT) que el modelo Ador-Crop en el mismo caso de estudio. El modelo EPICphase explicó el 44% de la variabilidad de la biomasa y del rendimiento en grano. La combinación de EPICphase y el modelo de riego por aspersión explicó un poco mejor la variabilidad de la biomasa que la del rendimiento en grano (42% y 35%, respectivamente), aunque el error en la estimación del rendimiento en grano con el modelo acoplado fue mayor que con las dosis de riego medidas (1,55 t ha–1 vs. 1,22 t ha–1). El modelo DSSAT explicó el 39% de la variabilidad de la biomasa y el 38% de la variabilidad del rendimiento en grano. Cuando se combinó el modelo de riego por aspersión con el modelo DSSAT, se obtuvo un mejor resultado en la simulación de la biomasa (R2 = 41%) que en la del rendimiento en grano (R2 = 31%). El modelo EPICphase simuló de forma más precisa el rendimiento en grano que el modelo DSSAT porque predijo mejor el índice de área foliar máximo. La combinación del modelo de riego por aspersión con EPICphase y DSSAT simuló mejor el crecimiento y rendimiento del cultivo que cuando se combinó con el modelo Ador-Crop.

Five field experiments on barley and wheat have been carried out in North-Eastern Spain on the same field during the cropping seasons 1999-00 to 2003-04 to compare the effect of different harrowing adjustments on weed control, weed biomass and cereal yield. The variables considered were harrowing timing (pre- or early post-emergence), one or two passes, travelling direction, harrowing depth and speed compared with an untreated control and herbicide. Excepting year 2001, with very little weed emergence, mechanical control as a whole caused a significant weed plant reduction compared to the untreated plots in all years. No influence of harrowing depth and travelling speed and of pre-emergence harrowing were found in the trials. A single harrowing treatment conducted across the sowing direction gave the same or less control compared to harrowing along the sowing direction. Two harrowing passes achieved a higher efficacy than one single pass and little differences were detected if the second pass was conducted the same day, across the sowing direction or 15 days later. Despite herbicide had generally a higher efficacy than the harrowing treatments, in three out of five years it was found a mechanical control with the same control than herbicide. The effect of the different treatments on weed biomass was lower than on weed number and no significant differences were found for grain yield. Considering that an herbicide treatment in the present conditions is three times more expensive than harrowing, a single post-emergence harrowing can be considered a valid option for low and medium-infested cereal fields., En este trabajo se muestran los resultados de cinco experimentos de campo localizados en el noreste de España desde 1999-00 hasta 2003-04. En ellos se comparó el efecto de distintas formas de control mecánico de la flora arvense con grada de varillas flexibles sobre la densidad y biomasa de la misma y sobre la producción de cereal comparado con un control sin tratar y el uso de herbicidas. Las variables consideradas fueron: momento y número de pases de grada, profundidad, dirección y velocidad de los pases. Excepto en 2001, con una baja infestación, el control mecánico redujo la densidad de arvenses en comparación con las parcelas sin tratar. La profundidad y la velocidad de la labor no tuvieron influencia clara y realizar el pase en preemergencia del cereal resultó ineficaz probablemente debido a la falta de humedad. Dos pases resultaron más eficaces que uno y se encontraron pocas diferencias si el segundo se hacía en el mismo día, perpendicular o 15 días después. Aunque el herbicida tuvo generalmente mayor eficacia que los tratamientos mecánicos, en tres años se encontró un tratamiento mecánico con eficacia similar. El efecto de los distintos tratamientos sobre la biomasa de arvenses fue menor que sobre el número de las mismas y no hubo diferencias significativas sobre la producción. Dado que el tratamiento herbicida en las condiciones del ensayo fue tres veces más caro que el tratamiento mecánico, un único pase en post-emergencia puede ser una opción válida con infestaciones medias o bajas de malas hierbas.

Cropping systems like organic farming, selling products at a higher price and promoting environmental sustainability by reducing fertilizer and pesticides, can be more profitable than conventional systems. An economic evaluation of three cropping systems in a seven year period experiment was performed, using a common rotation (fallow-barley-vetch-durum wheat) in a semi-arid rainfed field of Spain. The minimum input system included mouldboard ploughing, cultivator preparation, sowing and harvest. The conventional system involved mineral fertilizer and herbicide treatments, while the organic system involved composted manure and mechanical weed control. The resulting economic margins were highest with the minimum input system, followed by the organic and conventional systems. If the cereal grain from the minimum input system was sold at a higher price on the organic market, this system was the most profitable. Without the price difference, the organic system was as profitable as the conventional one.Sistemas de cultivo como agricultura orgânica, cujos produtos têm custo mais alto, mas que promova sustentabilidade ambiental pela redução do uso de fertilizantes e pesticidas, pode ser mais lucrativo do que sistemas convencionais de cultivo. Efetuou-se uma avaliação econômica de três sistemas de cultivo num período experimental de sete anos, utilizando um sistema comum de rotação (pousio-cevada-ervilhaca-trigo duro), sem irrigação, em um local semi-árido da Espanha. O sistema de cultivo mínimo incluía aração com aiveca, preparo com cultivador, semeadura e colheita. O sistema convencional envolvia tratamentos com herbicidas e fertilizantes minerais, enquanto o sistema orgânico envolvia adubação com composto e controle mecânico de ervas invasoras. O sistema com maior retorno econômico foi o de cultivo mínimo, seguido do orgânico e do convencional. O sistema de cultivo mínimo foi o mais lucrativo quando o cereal foi vendido num preço mais alto no mercado orgânico. Sem essa diferença de preços os sistemas apresentaram lucratividades semelhantes.

10th Congres of the European Society of Agronomy. Bolonia, Italia, 15-19 septembre 2008., Maize grown in monoculture is a common practice in the irrigated areas of the Ebro Valley (Spain). Nitrate leaching in this area is associated to excessive N fertilization to maize and residual mineral N (Ninorg) left in the soil after crop harvest (Cavero et al., 2003). Winter cover crops could be sown after maize harvest. Deep rooted cover crops would scavenge residual Ninorg in the soil profile and incorporation of the cover crop biomass into the soil in early spring would provide N to the next spring maize crop (Isse et al, 1999). However, little is known about cover crop management and effects on irrigated maize in Mediterranean conditions., The aim of the study was (1) to quantify the effect of winter cover crops on N leaching and soil Ninorg in a maize monoculture; and (2) to quantify the effect of cover crops on maize grain yields., This work has been supported by the European Project "Qualiwater INCO Nº 015031", and by the project "AGL2008 0820-C05-01", financed by the Ministry of Education and Science of Spain, Spanish Government., This work has been supported by the European Project “Qualiwater INCO Nº015031”, and by the project “AGL2005-0820-C05-01”, financed by the Ministry of Education and Science of Spain, Spanish Government.