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UM2
Murviel-lès-Montpellier, France

Milano M.,UM2 | Ruelland D.,French National Center for Scientific Research | Dezetter A.,IRD Montpellier | Fabre J.,French National Center for Scientific Research | And 2 more authors.
Journal of Hydrology | Year: 2013

Worldwide studies have shown that the Mediterranean region is one of the most vulnerable areas to water crisis. The region is characterized by limited and unequally distributed water resources and increasing water demands. The Ebro catchment (85,000km2, Spain) is representative of this context. Since the late 1970s, a negative trend in river discharge has been observed, attributed to a decrease in mean precipitation, and a rise in mean temperature and in water consumption. Finally, over 230 storage dams regulate river discharge. In this context, an integrated water resources modeling framework was developed to evaluate the current and future capacity of water resources to meet domestic and agricultural water demands as well as environmental flow requirements. The approach was driven by a conceptual rainfall-runoff model generating water supplies and by a demand driven storage dam model. The approach defines current pressures on water resources and evaluates future changes in water allocation in the medium term under climatic and water use scenarios, considering changes in population and in irrigated areas. Currently, water demands in the Ebro catchment are satisfied. In 2050, water resources are projected to decrease by 15-35% during spring and summer, leading to growing competition among users and severe water shortages for irrigated agriculture. This study provides an original approach to identify the most vulnerable regions to water use conflicts. It also highlights the interest of integrated modeling for complete analysis of the ability of water resources to meet water demands in complex change scenarios as a support for decision making. © 2013 Elsevier B.V. Source


Kazi Tani Ch.,Abou Bekr Belkaid University Tlemcen | Le Bourgeois T.,CIRAD - Agricultural Research for Development | Munoz F.,UM2
Flora Mediterranea | Year: 2012

Algeria is the North African country with the largest number of alien weed species. The analysis of Oranie's weed flora showed 29 species of alien species which represents 1.62% from the 1,780 species of the whole spontaneous flora of the oranian phytogeographic territory and 6.82% of the local weed flora. Almost 40% of these species were native to the American continent and about 45% came from several tropical regions. The most representative life-history traits of these alien species compared to native ones were: annual cycle (79% versus 76%), summer germination (83% versus 15%), non-specialized dissemination strategies, but related with anthropic activities (72% versus 47%), self-pollination (75%), and the high proportion of C4 species (45% versus 4%). The agricultural biotopes mainly affected are summer-irrigated crops with short rotation and important nitrogenous fertilizers assignment. There are very few such habitats in Oranie, and few summer annuals in Algeria's flora. The success of alien weeds seems to result from suitability between environmental conditions of a newly created habitat (summer temperature, humidity, important nitrogen rate, frequent perturbations, short rotations, and ecological niches available) and species characteristics (annual type, summer germination, photosynthetic pathway in C4). Dispersal strategy and fecundation types seemed not to be of much importance to characterize these alien species. Source


Siupka P.,University of Aarhus | Hamming O.J.,University of Aarhus | Fretaud M.,Institute Pasteur Paris | Fretaud M.,French National Center for Scientific Research | And 4 more authors.
Genes and Immunity | Year: 2014

The class II cytokine family consists of small -helical signaling proteins including the interleukin-10 (IL-10)/IL-22 family, as well as interferons (IFNs). They regulate the innate immune response and in addition have an important role in protecting epithelial tissues. Teleost fish possess a class II cytokine system surprisingly similar to that of humans, and thus zebrafish offers an attractive model organism for investigating the role of class II cytokines in inflammation. However, the evolution of class II cytokines is critical to understand if we are to take full advantage of zebrafish as a model system. The small size and fast evolution of these cytokines obscure phylogenetic analyses based purely on sequences, but one can overcome this obstacle by using information contained within the structure of those molecules. Here we present the crystal structure of IL-22 from zebrafish (zIL-22) solved at 2.1 Å, which displays a typical class II cytokine architecture. We generated a structure-guided alignment of vertebrate class II cytokines and used it for phylogenetic analysis. Our analysis suggests that IL-22 and IL-26 arose early during the evolution of the IL-10-like cytokines. Thus, we propose an evolutionary scenario of class II cytokines in vertebrates, based on genomic and structural data. © 2014 Macmillan Publishers Limited All rights reserved. Source


Destercke S.,CIRAD - Agricultural Research for Development | Destercke S.,French National Center for Scientific Research | Buche P.,French National Institute for Agricultural Research | Buche P.,French National Center for Scientific Research | Guillard V.,UM2
Fuzzy Sets and Systems | Year: 2011

In this paper, we propose an approach to query a database when the user preferences are bipolar (i.e., express both constraints and wishes about the desired result) and the data stored in the database are imprecise. Results are then completely ordered with respect to these bipolar preferences, giving priority to constraints over wishes. Additionally, we propose a treatment that allows us to guarantee that any query will return a result, even if no element satisfies all constraints specified by the user. Such a treatment may be useful when user's constraints are unrealistic (i.e., cannot be all satisfied simultaneously) and when the user desires a guaranteed result. The approach is illustrated on a real-world problem concerning the selection of optimal packaging for fresh fruits and vegetables. © 2011 Elsevier B.V. All rights reserved. Source


Ruelland D.,French National Center for Scientific Research | Dezetter A.,IRD Montpellier | Hublart P.,UM2
IAHS-AISH Proceedings and Reports | Year: 2014

This study analyses the sensitivity of a hydrological model to different ways of interpolating climate forcing on the Elqui basin (5660 km2) in the Chilean Andes. A 36-year period (1976-2011) was chosen in order to account for the hydro-climatic variability. Precipitation and using the inverse distance weighted methods were interpolated on a 5 × 5 km grid based on 12 and eight stations, respectively. Elevation effects on precipitation and temperature distribution were considered using a digital elevation model. Two precipitation datasets (with and without a mean altitudinal gradient) and three temperature datasets (using constant or monthly lapse rates based on altitudinal bands) were computed. All dataset combinations were assessed through the calibration of the GR4j model including a snow reservoir. Calibration was performed by the succession of Rosenbrock and simplex algorithms using a multi-objective function. Results show that the dataset based on a constant lapse rate of 6.5°C/km for temperature and no elevation effects for precipitation is sufficient to accurately simulate discharge and the snowmelt regime of the catchment over the last 30 years. © Copyright 2014 1AHS Press. Source

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