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2. Type Ia supernova rate at a redshift of ~ 0.1

Author

Blanc, G., Afonso, C., Alard, C., Albert, J. N., Aldering, G., Amadon, A., Andersen, J., Ansari, R., Aubourg, E., Balland, C., Bareyre, P., Beaulieu, J. P., Charlot, X., Conley, A., Coutures, C., Dahlen, T., Derue, F., Fan, X., Ferlet, R., Folatelli, G., Fouque, P., Garavini, G., Glicenstein, J. F., Goldman, B., Goobar, A., Gould, A., Graff, D., Gros, M., Haissinski, J., Hamadache, C., Hardin, D., Hook, I. M., deKat, J., Kent, S., Kim, A., Lasserre, T., LeGuillou, L., Lesquoy, E., Loup, C., Magneville, C., Marquette, J. B., Maurice, E., Maury, A., Milsztajn, A., Moniez, M., Mouchet, M., Newberg, H., Nobili, S., Palanque-Delabrouille, N., Perdereau, O., Prevot, L., Rahal, Y. R., Regnault, N., Rich, J., Ruiz-Lapuente, P., Spiro, M., Tisserand, P., Vidal-Madjar, A., Vigroux, L., Walton, N. A., and Zylberajch, S.

Subjects
Astrophysics
Abstract

We present the type Ia rate measurement based on two EROS supernova search campaigns (in 1999 and 2000). Sixteen supernovae identified as type Ia were discovered. The measurement of the detection efficiency, using a Monte Carlo simulation, provides the type Ia supernova explosion rate at a redshift ~ 0.13. The result is $0.125^{+0.044+0.028}_{-0.034-0.028} h_{70}^2$ SNu where 1 SNu = 1 SN / $10^{10} L_{sun}^B$ / century. This value is compatible with the previous EROS measurement (Hardin et al. 2000), done with a much smaller sample, at a similar redshift. Comparison with other values at different redshifts suggests an evolution of the type Ia supernova rate., Comment: Accepted for publication in Astronomy & Astrophysics (15 pages, 16 figures)

Published
2004
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3. Type Ia supernova rate at $z \sim 0.1$

Author

Hardin, D., Afonso, C., Alard, C., Albert, J. N., Amadon, A., Andersen, J., Ansari, R., Aubourg, É., Bareyre, P., Bauer, F., Beaulieu, J. P., Blanc, G., Bouquet, A., Char, S., Charlot, X., Couchot, F., Coutures, C., Derue, F., Ferlet, R., Glicenstein, J. F., Goldman, B., Gould, A., Graff, D., Gros, M., Haissinski, J., Hamilton, J. C., de Kat, J., Kim, A., Lasserre, T., Lesquoy, É., Loup, C., Magneville, C., Mansoux, B., Marquette, J. B., Maurice, É., Milsztajn, A., Moniez, M., Palanque-Delabrouille, N., Perdereau, O., Prévot, L., Regnault, N., Rich, J., Spiro, M., Vidal-Madjar, A., Vigroux, L., Zylberajch, S., and collaboration, The EROS

Subjects
Astrophysics
Abstract

We present the EROS nearby supernova ($z \sim 0.02 - 0.2$) search and the analysis of the first year of data (1997). A total of 80 square degrees were surveyed. Eight supernov{\ae} were detected, four of which were spectroscopically identified as type Ia supernov{\ae}. The search efficiency was determined with a Monte-Carlo simulation taking into account the efficiencies for both supernova detection and host galaxy identification. Assuming that for a given galaxy the supernova rate is proportional to the galactic luminosity, we compute a type Ia supernova explosion rate of: ${\cal R} = 0.44 {}_{-0.21}^{+0.35} {}_{-0.07}^{+0.13} h^2: / 10^{10} \lbsun / 100 {\rm yrs}$ at an average redshift of $\sim 0.1$ where the errors are respectively statistical and systematic (type misidentification included)., Comment: 8 pages, 6 figures, accepted in A&A

Published
2000

4. EROS Variable Stars : Discovery of Beat Cepheids in the Small Magellanic Cloud and the effect of metallicity on pulsation

Author

Beaulieu, J. P., Krockenberger, M., Sasselov, D. D., Renault, C., Ferlet, R., Vidal-Madjar, A., Maurice, E., Prévot, L., Aubourg, E., Bareyre, P., Brehin, S., Coutures, C., Delabrouille, N., de Kat, J., Gros, M., Laurent, B., Lachièze-Rey, M., Lesquoy, E., Magneville, C., Milsztajn, A., Moscoso, L., Queinnec, F., Rich, J., Spiro, M., Vigroux, L., Zylberajch, S., Ansari, R., Cavalier, F., Moniez, M., and Gry., C.

Subjects
Astrophysics
Abstract

We report the discovery of eleven beat Cepheids in the Small Magellanic Cloud, using data obtained by the EROS microlensing survey. Four stars are beating in the fundamental and first overtone mode (F/1OT), seven are beating in the first and second overtone (1OT/2OT). The SMC F/1OT ratio is systematically higher than the LMC F/1OT, while the 1OT/2OT period ratio in the SMC Cepheids is the same as the LMC one., Comment: 4 pages, Latex file with 4 .ps figures. accepted for publication in A A Letters

Published
1997

5. The effect of metallicity on the Cepheid distance scale and its implications for the Hubble constant ($H_0$) determination

Author

Beaulieu, J. P., Sasselov, D. D., Renault, C., Grison, P., Ferlet, R., Vidal-Madjar, A., Maurice, E., Prévot, L., Aubourg, E., Bareyre, P., Brehin, S., Coutures, C., Delabrouille, N., de Kat, J., Gros, M., Laurent, B., Lachièze-Rey, M., Lesquoy, E., Magneville, C., Milsztajn, A., Moscoso, L., Queinnec, F., Rich, J., Spiro, M., Vigroux, L., Zylberajch, S., Ansari, R., Cavalier, F., Moniez, M., Gry, C., Guibert, J., Moreau, O., and Tajhmady, F.

Subjects
Astrophysics
Abstract

Recent HST determinations of the expansion's rate of the Universe (the Hubble constant, H_0) assumed that the Cepheid Period-Luminosity relation at V and I are independent of metallicity (Freedman, et al., 1996, Saha et al., 1996, Tanvir et al., 1995). The three groups obtain different vales for H_0. We note that most of this discrepancy stems from the asumption (by both groups) that the Period-Luminosity relation is independent of metallicity. We come to this conclusion as a result of our study of the Period-Luminosity relation of 481 Cepheids with 3 millions two colour measurements in the Large Magellanic Cloud and the Small Magellanic Cloud obtained as a by-product of the EROS microlensing survey. We find that the derived interstellar absorption corrections are particularly sensitive to the metallicity and when our result is applied to recent estimates based on HST Cepheids observations it makes the low-H_0 values higher and the high-H_0 value lower, bringing those discrepant estimates into agrement around $H_0 \approx 70 km/s Mpc^{-1}$., Comment: 4 pages, Latex, with 2 .ps accepted for publication astronomy and astrophysics Letters

Published
1996

6. Metallicity Effects on the Cepheid Extragalactic Distance Scale from EROS photometry in LMC and SMC

Author

Sasselov, D. D., Beaulieu, J. P., Renault, C., Grison, P., Ferlet, R., Vidal-Madjar, A., Maurice, E., Prévot, L., Aubourg, E., Bareyre, P., Brehin, S., Coutures, C., Delabrouille, N., de Kat, J., Gros, M., Laurent, B., Lachièze-Rey, M., Lesquoy, E., Magneville, C., Milsztajn, A., Moscoso, L., Queinnec, F., Rich, J., Spiro, M., Vigroux, L., Zylberajch, S., Ansari, R., Cavalier, F., Moniez, M., Gry, C., Guibert, J., Moreau, O., and Tajhmady, F.

Subjects
Astrophysics
Abstract

This is an investigation of the period-luminosity relation of classical Cepheids in samples of different metallicity. It is based on 481 Cepheids in the Large and Small Magellanic Clouds from the blue and red filter CCD observations (most similar to V_J & R_J) of the French EROS microlensing project. The data-set is complete and provides an excellent basis for a differential analysis between LMC and SMC. In comparison to previous studies of effects on the PL-relation, the EROS data-set offers extremely well-sampled light curves and well-filled instability strips. This allows reliable separation of Cepheids pulsating in the fundamental and the first overtone mode and derivation of differential reddening. Our main result concerns the determination of distances to galaxies which are inferred by using the LMC as a base and using two color photometry to establish the amount of reddening. We find a zero-point offset between SMC and LMC which amounts to a difference between inferred and true distance modulus of 0.14 \pm 0.06 mag in the VI_c system. The offset is exactly the same in both sets of PL-relations - of the fundamental and of the first overtone mode Cepheids. No effect is seen on the slopes of the PL-relations, although the fundamental and the first overtone mode Cepheids have different PL slopes. We attribute the color and the zero-point offset to the difference in metallicity between the SMC and LMC Cepheids. A metallicity effect of that small magnitude still has important consequencies for the inferred Cepheid distances and the determination of H_0. When applied to recent estimates based on HST Cepheid observations, our metallicity dependence makes the low-H_0 values (Sandage et al. 1994) higher and the high-H_0 values (Freedman et al. 1994b) lower, thus bringing those, Comment: 14 pages, Latex, with 8 .ps accepted for publication in astronomy and astrophysics

Published
1996

7. Observational Limits on Machos in the Galactic Halo

Author

EROS collaboration, Renault, C., Afonso, C., Aubourg, E., Bareyre, P., Bauer, F., Brehin, S., Coutures, C., Gaucherel, C., Glicenstein, J. F., Goldman, B., Gros, M., Hardin, D., de Kat, J., Lachieze-Rey, M., Laurent, B., Lesquoy, E., Magneville, C., Milsztajn, A., Moscoso, L., Palanque-Delabrouille, N., Queinnec, F., Rich, J., Spiro, M., Vigroux, L., Zylberajch, S., Ansari, R., Cavalier, F., Couchot, F., Mansoux, B., Moniez, M., Perdereau, O., Beaulieu, J. -Ph., Ferlet, R., Grison, Ph., Vidal-Madjar, A., Guibert, J., Moreau, O., Maurice, E., Prevot, L., Gry, C., Char, S., and Fernandez, J.

Subjects
Astrophysics
Abstract

We present final results from the first phase of the EROS search for gravitational microlensing of stars in the Magellanic Clouds by unseen deflectors (machos: MAssive Compact Halo Objects). The search is sensitive to events with time scales between 15 minutes and 200 days corresponding to deflector masses in the range 1.e-7 to a few solar masses. Two events were observed that are compatible with microlensing by objects of mass of about 0.1 Mo. By comparing the results with the expected number of events for various models of the Galaxy, we conclude that machos in the mass range [1.e-7, 0.02] Mo make up less than 20% (95% C.L.) of the Halo dark matter., Comment: 4 pages, 3 Postscript figures, to be published in Astronomy & Astrophysics

Published
1996

8. EROS VARIABLE STARS : FUNDAMENTAL-MODE AND FIRST OVERTONE CEPHEIDS IN THE BAR OF THE LARGE MAGELLANIC CLOUD

Author

Beaulieu, J. P., Grison, P., Tobin, W., Pritchard, J. D., Ferlet, R., Vidal-Madjar, A., Maurice, E., Prevot, L., Gry, C., Guibert, J., Moreau, O., Tajahmady, F., Aubourg, E., Bareyre, P., Brehin, S., Gros, M., Lachieze-Rey, M., Laurent, B., Lesquoy, E., Magneville, C., Milsztajn, A., Moscoso, L., Queinnec, F., Rich, J., Spiro, M., Vigroux, L., Zylberajch, S., Ansari, R., Cavalier, F., and Moniez, M.

Subjects
Astrophysics
Abstract

We present CCD phase-binned light curves at 490 nm for 97 Cepheid variable stars in the bar of the LMC. The photometry was obtained as part of the French EROS project and has excellent phase coverage, permitting accurate decomposition into Fourier components. We identify as `sinusoidal' or s-Cepheids those stars with periods less than 5.5 d and small second-harmonic components. These stars comprise $\sim$30% of our sample and most form a sequence $\sim$1 mag brighter than the LMC classical Cepheids in the period-luminosity diagram. They are also generally bluer and have lower-amplitude light curves. We infer that the s-Cepheids are first-overtone pulsators because, when their periods are converted to expected fundamental-mode values, they obey a common period-luminosity-colour relation with classical Cepheids. This also confirms the reality of the colour term in the Cepheid period-luminosity-colour relation. Further, the blue edge of the classical Cepheid instability strip agrees well with the theoretical calculations for the fundamental mode made by Chiosi et al. (1993) for the Hertzsprung-Russell and period-luminosity diagrams, but we find that our observed s-Cepheids are $>0.2$ mag brighter and bluer than the Chiosi et al.\ predictions for the first-overtone. We identify a number of features in plots of our stars' Fourier-component amplitude ratios and phase differences. These features have been identified with resonances between different pulsation modes. In the LMC we find these features seem to occur at periods very similar to Galactic ones for classical Cepheids, but at different periods for s-Cepheids. We discover a double-mode Cepheid in the LMC, for which $P({\rm first overtone})/P({\rm fundamental}) = 0.710 \pm 0.001$, very similar to observed ratios for Galactic double-mode Cepheids., Comment: 19 pages, uuencoded compressed PS file, including 14 figures. Accepted for publication in Astronomy and Astrophysics, February-2-1995

Published
1995

9. SEARCH FOR VERY LOW MASS OBJECTS IN THE GALACTIC HALO

Author

EROS collaboration, Aubourg, E., Bareyre, P., Brehin, S., Gros, M., Lachieze-Rey, M., Laurent, B., Lesquoy, E., Magneville, C., Milsztajn, A., Moscoso, L., Queinnec, F., Rich, J., Spiro, M., Vigroux, L., Zylberajch, S., Ansari, R., Cavalier, F., Moniez, M., Beaulieu, J. P., Ferlet, R., Grison, Ph., Vidal-Madjar, A., Maurice, E., Prevot, L., Gry, C., Guibert, J., Moreau, O., and Tajahmady, F.

Subjects
Astrophysics
Abstract

We present results from a search for gravitational microlensing of stars in the Large Magellanic Cloud by low mass objects in the Galactic Halo. The search uses the CCD light curves of about 82,000 stars with up to 46 measurements per night over a period of 10 months. No light curve exhibits a form that is consistent with a microlensing event of maximum amplification greater than 1.2. This null result makes it unlikely that the Halo is dominated by objects in the mass range $5 10^{-8}M_{\odot} < M <5 10^{-4}M_{\odot} $. keywords{Galaxy : Halo, kinematics and dynamics, stellar content -- Cosmology : dark matter, gravitational lensing}, Comment: to appear in Astronomy & Astrophysics (Accepted for publication in January 1995), 5 pages in uuencoded, compressed postscript, including figures

Published
1995

10. Spectroscopic Studies of the Two Eros Candidate Microlensed Stars

Author

Beaulieu, J. P., Ferlet, R., Grison, Ph., Vidal-Madjar, A., Kneib, J. P., Maurice, E., Prevot, L., Gry, C., Guibert, J., Moreau, O., Tajahmady, F., Aubourg, E., Bareyre, P., Brehin, S., Gros, M., Lachieze-Rey, M., Laurent, B., Lesquoy, E., Magneville, C., Milsztajn, A., Moscoso, L., Queinnec, F., Rich, J., Spiro, M., Vigroux, L., Zylberajch, S., Ansari, R., Cavalier, F., and Moniez, M.

Subjects
Astrophysics
Abstract

Low resolution spectroscopy, and UBVRI photometry, have been obtained for the two EROS microlensing candidates. Radial velocities indicate that both stars are members of the Large Magellanic Cloud. The spectrum and the colours of EROS1, the first candidate, reveal that it is a moderately reddened main-sequence B star with H emission lines. The presence of H absorption lines seems to be more the signature of a normal star than that of a cataclysmic variable. As to EROS2, the second candidate, its spectrum and photometry are those of an unreddened normal main-sequence A star, but it cannot be totally excluded that they represent those of a nova in the pre-outburst phase. Although it is not yet possible to exclude intrinsic stellar variations, the interpretation in terms of microlensing effects remain the most natural one., Comment: 5 pages, uuencoded compressed PS file, including 1 figure. submitted to Astronomy and Astrophysics, 28 July, 1994

Published
1994

13. Pre-Main-Sequence Star Candidates in the Bar of the Large Magellanic Cloud

Author

Beaulieu, J. P., Grison, P., Julien, R., Lanciaux, C., Ferlet, R., Vidal-Madjar, A., Bertin, E., Maurice, E., Prévot, L., Gry, C., Guibert, J., Moreau, O., Tajhmady, F., Aubourg, E., Bareyre, P., de Kat, J., Gros, M., Laurent, B., Lachièze-Rey, M., Lesquoy, E., Magneville, C., Milsztajn, A., Moscoso, L., Queinnec, F., Renault, C., Rich, J., Spiro, M., Vigroux, L., Zylberajch, S., Ansari, R., Cavalier, F., and Moniez, M.

Published
1996

14. Team DMG at CMCL 2022 Shared Task: Transformer Adapters for the Multi- and Cross-Lingual Prediction of Human Reading Behavior

Author

Takmaz, E., Chersoni, E., Hollenstein, N., Jacobs, C., Oseki, Y., Prévot, L., Santus, E., and ILLC (FNWI)

Abstract

In this paper, we present the details of our approaches that attained the second place in the shared task of the ACL 2022 Cognitive Modeling and Computational Linguistics Workshop. The shared task is focused on multi- and cross-lingual prediction of eye movement features in human reading behavior, which could provide valuable information regarding language processing. To this end, we train `adapters' inserted into the layers of frozen transformer-based pretrained language models. We find that multilingual models equipped with adapters perform well in predicting eye-tracking features. Our results suggest that utilizing language- and task-specific adapters is beneficial and translating test sets into similar languages that exist in the training set could help with zero-shot transferability in the prediction of human reading behavior.

Published
2022

15. Less Descriptive yet Discriminative: Quantifying the Properties of Multimodal Referring Utterances via CLIP

Author

Takmaz, E., Pezzelle, S., Fernández, R., Chersoni, E., Hollenstein, N., Jacobs, C., Oseki, Y., Prévot, L., Santus, E., and ILLC (FNWI)

Abstract

In this work, we use a transformer-based pre-trained multimodal model, CLIP, to shed light on the mechanisms employed by human speakers when referring to visual entities. In particular, we use CLIP to quantify the degree of descriptiveness (how well an utterance describes an image in isolation) and discriminativeness (to what extent an utterance is effective in picking out a single image among similar images) of human referring utterances within multimodal dialogues. Overall, our results show that utterances become less descriptive over time while their discriminativeness remains unchanged. Through analysis, we propose that this trend could be due to participants relying on the previous mentions in the dialogue history, as well as being able to distill the most discriminative information from the visual context. In general, our study opens up the possibility of using this and similar models to quantify patterns in human data and shed light on the underlying cognitive mechanisms.

Published
2022

16. Evaluating Word Embeddings for Language Acquisition

Author

Alhama, R.G., Rowland, C.F., Kidd, E., Chersoni, E., Jacobs, C., Oseki, Y., Prévot, L., Santus, E., Cognitive Science & AI, Chersoni, E., Jacobs, C., Oseki, Y., Prévot, L., and Santus, E.

Subjects
Language Acquisition, Psycholinguistics, business.industry, Process (engineering), Computer science, 05 social sciences, Word Embeddings, Semantic Relations, Context (language use), 010501 environmental sciences, computer.software_genre, Language acquisition, 01 natural sciences, 050105 experimental psychology, Age of Acquisition, Semantic memory, 0501 psychology and cognitive sciences, Artificial intelligence, business, computer, Word (computer architecture), Natural language processing, 0105 earth and related environmental sciences
Abstract

Item does not contain fulltext Continuous vector word representations (or word embeddings) have shown success in capturing semantic relations between words, as evidenced by evaluation against behavioral data of adult performance on semantic tasks (Pereira et al., 2016). Adult semantic knowledge is the endpoint of a language acquisition process; thus, a relevant question is whether these models can also capture emerging word representations of young language learners. However, the data for children’s semantic knowledge across development is scarce. In this paper, we propose to bridge this gap by using Age of Acquisition norms to evaluate word embeddings learnt from child-directed input. We present two methods that evaluate word embeddings in terms of (a) the semantic neighbourhood density of learnt words, and (b) convergence to adult word associations. We apply our methods to bag-of-words models, and find that (1) children acquire words with fewer semantic neighbours earlier, and (2) young learners only attend to very local context. These findings provide converging evidence for validity of our methods in understanding the prerequisite features for a distributional model of word learning. Workshop on Cognitive Modeling and Computational Linguistics (CMCL 2020) (2020, 19 November)

Published
2020

19. Evaluating word embeddings for language acquisition

Author

Chersoni, E., Jacobs, C., Oseki, Y., Prévot, L., Santus, E., Alhama, R.G., Rowland, C.F., Kidd, E., Chersoni, E., Jacobs, C., Oseki, Y., Prévot, L., Santus, E., Alhama, R.G., Rowland, C.F., and Kidd, E.

Abstract

Workshop on Cognitive Modeling and Computational Linguistics (CMCL 2020) (2020, 19 November), Item does not contain fulltext, Continuous vector word representations (or word embeddings) have shown success in capturing semantic relations between words, as evidenced by evaluation against behavioral data of adult performance on semantic tasks (Pereira et al., 2016). Adult semantic knowledge is the endpoint of a language acquisition process; thus, a relevant question is whether these models can also capture emerging word representations of young language learners. However, the data for children’s semantic knowledge across development is scarce. In this paper, we propose to bridge this gap by using Age of Acquisition norms to evaluate word embeddings learnt from child-directed input. We present two methods that evaluate word embeddings in terms of (a) the semantic neighbourhood density of learnt words, and (b) convergence to adult word associations. We apply our methods to bag-of-words models, and find that (1) children acquire words with fewer semantic neighbours earlier, and (2) young learners only attend to very local context. These findings provide converging evidence for validity of our methods in understanding the prerequisite features for a distributional model of word learning.

Published
2020

21. Quantifiers in a Multimodal World: Hallucinating Vision with Language and Sound

Author

Testoni, A., Pezzelle, S., Bernardi, R., Chersoni, E., Jacobs, C., Lenci, A., Linzen, T., Prévot, L., Santus, E., Language and Computation (ILLC, FNWI/FGw), and ILLC (FNWI)

Subjects
Modalities, Modality (human–computer interaction), Hallucinating, Computer science, Speech recognition, Perception, media_common.quotation_subject, Multisensory integration, Sensory system, media_common, Task (project management)
Abstract

Inspired by the literature on multisensory integration, we develop a computational model to ground quantifiers in perception. The model learns to pick, out of nine quantifiers (‘few’, ‘many’, ‘all’, etc.), the one that is more likely to describe the percent of animals in a visual-auditory input containing both animals and artifacts. We show that relying on concurrent sensory inputs increases model performance on the quantification task. Moreover, we evaluate the model in a situation in which only the auditory modality is given, while the visual one is ‘hallucinanted’ either from the auditory input itself or from a linguistic caption describing the quantity of entities in the auditory input. This way, the model exploits prior associations between modalities. We show that the model profits from the prior knowledge and outperforms the auditory-only setting.

Published
2019

25. Estimation des flux d'échanges surface-atmosphère par les méthodes de covariance turbulente et de scintillométrie infra-rouge : premiers résultats sur les bassins de l'Orgeval et de Naizin

Author

Cappelaere, B., Arpin-Pont, F., Flechard, C., Guérin, A., Ansart, P., Barral, H., Chazarin, J. P., Cohard, J. M., Demarty, J., Faucheux, M., Fovet, O., Hamon, Y., Prévot, L., Tallec, G., Hydrosciences Montpellier (HSM), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Insitut Français des Productions Cidricoles (IFPC), Irstea, Institut des Géosciences de l’Environnement (IGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Recherche pour le Développement (IRD)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Sol Agro et hydrosystème Spatialisation (SAS), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de la Recherche Agronomique (INRA), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut Français des Productions Cidricoles (IFPC), Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)

Subjects
[SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

26. OMERE: A Long‐Term Observatory of Soil and Water Resources, in Interaction with Agricultural and Land Management in Mediterranean Hilly Catchments

Author

Molénat, J., primary, Raclot, D., additional, Zitouna, R., additional, Andrieux, P., additional, Coulouma, G., additional, Feurer, D., additional, Grunberger, O., additional, Lamachère, J.M., additional, Bailly, J.S., additional, Belotti, J.L., additional, Ben Azzez, K., additional, Ben Mechlia, N., additional, Ben Younès Louati, M., additional, Biarnès, A., additional, Blanca, Y., additional, Carrière, D., additional, Chaabane, H., additional, Dagès, C., additional, Debabria, A., additional, Dubreuil, A., additional, Fabre, J.C., additional, Fages, D., additional, Floure, C., additional, Garnier, F., additional, Geniez, C., additional, Gomez, C., additional, Hamdi, R., additional, Huttel, O., additional, Jacob, F., additional, Jenhaoui, Z., additional, Lagacherie, P., additional, Le Bissonnais, Y., additional, Louati, R., additional, Louchart, X., additional, Mekki, I., additional, Moussa, R., additional, Negro, S., additional, Pépin, Y., additional, Prévot, L., additional, Samouelian, A., additional, Seidel, J.L., additional, Trotoux, G., additional, Troiano, S., additional, Vinatier, F., additional, Zante, P., additional, Zrelli, J., additional, Albergel, J., additional, and Voltz, M., additional

Published
2018
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28. Le WP.1 du projet Equipex CRITEX: Mesure des échanges sol-végétation-atmosphère

Author

Arpin-Pont, F., Barral, H., Cappelaere, B., Cohard, J.-M., Prévot, L., Demarty, J., Chazarin, J. P., Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Hydrosciences Montpellier (HSM), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'étude des transferts en hydrologie et environnement (LTHE), Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
[SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

29. Long term agro-ecosystem observatories in the Mediterranean

Author

Voltz, M., Mekki, I., Molénat, Jérôme, Prévot, L., Raclot, Damien, Zitouna-Chebbi, R., Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Institut National de Recherche en Génie Rural Eaux et Forêts (INRGREF), Ecole Nationale du Génie Rural, des Eaux et des Forêts (ENGREF)-Institution de la Recherche et de l'Enseignement Supérieur Agricoles [Tunis] (IRESA), Jean-Paul Moatti, Stéphane Thiébault, Thiébault, S. (ed.), and Moatti, Jean-Paul (ed.)

Subjects
SECHERESSE, SOL, GESTION, AGRICULTURE, 1993 2015, ECOSYSTEME, RESSOURCES EN EAU, FACTEUR ANTHROPIQUE, BILAN HYDROLOGIQUE, FACTEUR CLIMATIQUE, CHANGEMENT CLIMATIQUE, OBSERVATOIRE, [SDE]Environmental Sciences, SERVICE ECOSYSTEMIQUE, DEVELOPPEMENT DURABLE, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

30. Vigne et vins

Author

Jacob, Frédéric, Lagacherie, P., and Prévot, L.

Published
2015

31. Adapting Landscape Mosaics of medIteranean Rainfed Agrosystems for a sustainable management of crop production, water and soil resources: the ALMIRA project

Author

Frédéric Jacob, Mekki, I., Mohamed Taha Chikhaoui, Amami, H., Bahri, H., Jean-Stéphane Bailly, Ben Mechlia, N., Anne Biarnès, Bouaziz, A., Nissaf Boudhina, Nesrine Chehata, François Colin, Demarchi, F., Amrani, E. M., J-C, Fabre, Alia Gana, Gary, C., Cecile Gomez, Cécile Hérivaux, Huard, F., Khattabi, A., Philippe Lagacherie, Yves Le Bissonnais, Jean-Paul Lhomme, Masmoudi, M., Carlo Montes, Roger Moussa, Moussadek, R., Naimi, M., Ouerghemmi, W., Olivier Planchon, Prévot, L., Hervé Quénol, Michael Rabotin, Damien Raclot, Jean-Daniel Rinaudo, Sabir, M., Sannier, C., Vinatier, F., Oltz, M., Zairi, A., Rim Zitouna, Institut National de Recherche en Génie Rural Eaux et Forêts (INRGREF), Ecole Nationale du Génie Rural, des Eaux et des Forêts (ENGREF), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Franche-Comté (UFC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Technologie de Belfort-Montbeliard (UTBM), National Research Institute of Rural Engineering, Water and Forests (INRGREF), Université de Carthage - University of Carthage, Territoires, Environnement, Télédétection et Information Spatiale (UMR TETIS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut de Recherche pour le Développement (IRD [ Madagascar])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Department of Infectious Diseases, Lucien Hussel Hospital Center, Institut National Agronomique de Tunisie, Institut Polytechnique de Bordeaux (Bordeaux INP), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire Dynamiques Sociales et Recomposition des Espaces (LADYSS), Université Paris Diderot - Paris 7 (UPD7)-Université Paris Nanterre (UPN)-Université Paris 8 Vincennes-Saint-Denis (UP8)-Université Panthéon-Sorbonne (UP1)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche sur le maghreb contemporain (IRMC), MIN AFF ETRANG-Centre National de la Recherche Scientifique (CNRS), Fonctionnement et conduite des systèmes de culture tropicaux et méditerranéens (UMR SYSTEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Kobe University, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), UE Agroclim (UE AGROCLIM), Institut National de la Recherche Agronomique (INRA), Laboratoire d'étude des interactions entre sols, agrosystèmes et hydrosystèmes (LISAH), Laboratoire QUARTZ (QUARTZ ), Université Paris 8 Vincennes-Saint-Denis (UP8)-SUPMECA - Institut supérieur de mécanique de Paris-Ecole Nationale Supérieure de l'Electronique et de ses Applications (ENSEA)-Ecole Internationale des Sciences du Traitement de l'Information (EISTI), École Nationale d'Ingénieurs de Sfax | National School of Engineers of Sfax (ENIS), Laboratoire Biodiversité et Dynamique des Ecosystèmes (BioDEcos), Université Cadi Ayyad [Marrakech] (UCA)-Faculté des Sciences-Semlalia, Centre National de la Recherche Scientifique (CNRS), Études des Structures, des Processus d’Adaptation et des Changements de l’Espace (ESPACE), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Avignon Université (AU)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Labo BioMCo - INAPG, Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie]), Laboratoire Parole et Langage (LPL), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-Université de Nantes (UN)-École pratique des hautes études (EPHE)-Université de Brest (UBO)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Ecole Nationale Forestière d'Ingénieurs du Maroc (ENFI), SIRS, Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Ecole Nationale du Génie Rural, des Eaux et des Forêts (ENGREF)-Institution de la Recherche et de l'Enseignement Supérieur Agricoles [Tunis] (IRESA), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris 8 Vincennes-Saint-Denis (UP8)-Université Paris Nanterre (UPN)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Agroclim (AGROCLIM), Université Paris 8 Vincennes-Saint-Denis (UP8)-SUPMECA - Institut supérieur de mécanique de Paris (SUPMECA)-Ecole Nationale Supérieure de l'Electronique et de ses Applications (ENSEA)-Ecole Internationale des Sciences du Traitement de l'Information (EISTI), Faculté des Sciences-Semlalia-Université Cadi Ayyad [Marrakech] (UCA), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Avignon Université (AU)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN), Université de Nantes (UN)-Université de Nantes (UN), Ecole Nationale Forestière d'Ingénieurs du Maroc [Salé] (ENFI), Filatre, Annabelle, Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Aix Marseille Université (AMU)-MIN AFF ETRANG-Centre National de la Recherche Scientifique (CNRS), Université Paris 8 Vincennes-Saint-Denis (UP8)-Ecole Nationale Supérieure de l'Electronique et de ses Applications (ENSEA)-SUPMECA - Institut supérieur de mécanique de Paris (SUPMECA)-Ecole Internationale des Sciences du Traitement de l'Information (EISTI), Faculté des Sciences Semlalia [Marrakech], Université Cadi Ayyad [Marrakech] (UCA)-Université Cadi Ayyad [Marrakech] (UCA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), Centre National de la Recherche Scientifique (CNRS)-Université Panthéon-Sorbonne (UP1)-Université Paris 8 Vincennes-Saint-Denis (UP8)-Université Paris Nanterre (UPN)-Université Paris Diderot - Paris 7 (UPD7), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre International de Hautes Etudes Agronomiques Méditerranéennes - Institut Agronomique Méditerranéen de Montpellier (CIHEAM-IAMM), Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre International de Hautes Études Agronomiques Méditerranéennes (CIHEAM)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Université Paris 8 Vincennes-Saint-Denis (UP8)-Ecole Nationale Supérieure de l'Electronique et de ses Applications (ENSEA)-SUPMECA - Institut supérieur de mécanique de Paris-Ecole Internationale des Sciences du Traitement de l'Information (EISTI), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Brest (UBO)-École pratique des hautes études (EPHE)-Université de Nantes (UN)-Université d'Angers (UA)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), Aix Marseille Université (AMU)-Ministère de l'Europe et des Affaires étrangères (MEAE)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Normandie Université (NU)-Université d'Angers (UA)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (IGARUN)

Subjects
[SDU.STU] Sciences of the Universe [physics]/Earth Sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract

International audience; Water erosion of cultivated soils is a threat to the sustainability of agriculture, especially in Mediterranean areas. For a long time, Mediterranean farmers have thus adopted some soil conservation practices. Actual ditch networks, which are generally associated with terraces, result from historical successive farmer settlements and are one of these soil conservation practices. By intercepting surface run-off, ditches decrease slope length and prevent soil erosion on downstream plots. However, since water erosion hazard and ditch network geometries are highly variable in vineyards landscape and since ditch building and maintaining are costly, the objective of this study was to identify and map the resulting efficiency of ditch networks in preventing soil erosion. For a given area, a ditch network efficiency is defined here as the balance between the network density, i.e. network cumulated length for a given area unit, and the erosion sensitivity over an area which measures the performance of the ditch network in limiting soil erosion. The erosion efficiency of ditch networks was thus identified using both i) computer generated ditch networks with various spatial configurations and ii) the stream power index as an erosion sensitivity indicator, computed from a DTM in which each ditch network was burned. The stream power index of the actual networks were compared with a set of generated networks whose density and topology were selected to maximize the performance in preventing soil erosion thanks to the use of a self-developed optimized stochastic network generator. For four 1 km2 hillslopes, we showed that the performances of actual networks to prevent soil erosion was among the best that were obtained by simulated networks with even greater densities. Furthermore, we showed that the stream power index values that accounted for the actual ditch networks to prevent soil erosion hazard was both minimal and weakly variable in the whole study area (30 km2 ) at hillslope scale, whatever the other erosion factors, namely topography and landuse. This suggested that densities and topologies of actual ditch networks in the catchment have been optimized by farmers through individual acts along the last centuries in order to limit the soil erosion hazard. This also confirms there is very little room to propose new ditch network spatial configurations that better prevent vineyards soil erosion.

Published
2014

32. Water balance for different land use and crop sequences under semiarid environment

Author

Mekki, I., Zitouna Chebbi, R., Jacob, Frédéric, Masmoudi, M., Prévot, L., Ben Mechlia, N., Voltz, M., and Albergel, Jean

Subjects
EVAPOTRANSPIRATION, BILAN HYDRIQUE, SYSTEME DE CULTURE, HUMIDITE DU SOL, GESTION DE L'EAU, EAU DU SOL, RESSOURCES EN EAU, RUISSELLEMENT, CULTURE, BASSIN VERSANT, VARIATION ANNUELLE, PLUIE, PRECIPITATION, RESSOURCES EN SOL, UTILISATION DU SOL, COLLINE
Abstract

In semiarid agrosystems, improving management of soil and water resources requires developing reliable means for characterizing the temporal dynamics of soil water balance in a spatially distributed manner. The purpose of this study is to analyze soil water balance in relation to natural drivers (i.e. rainfall and soil properties) and anthropogenic forcing (i.e. land use and crop successions). We focuson a hilly watershed devoted to rainfed agriculture, so-called the Kamech watershed, which is located in the Cap Bon Peninsula, north-eastern Tunisia. The soil moisture analysis is based on in-situ data collected in different fields and during various crop growth cycles under the common cereals/legumes/pasture cropping systems. In-situ data include water balance components and vegetation parameters. The results show that annual rainfall is mainly converted into evapotranspiration during the growing cycle for different land uses. The runoff amounts, for most of the sites, correspond to less than 10% of the rainfall amount. The evapotranspiration ratio significantly differs in relation to soil properties and cumulated rainfall. We observe large differences in soil water dynamics among the legumes (fababean and chickpea) and cereals (wheat, oat, and triticale). Soil water is larger for legume crops, despite substantial plant growth during winter-spring. This is ascribed to the shallow root systems of fababean and chickpea that induces a restricted access to deep water. Despite drought conditions during summer, bare soil following annual pasture and legumes corresponded to larger amounts of soil water as compared to cereals. The amount of available water observed ranges from 0 mm to nearly 100 mm.

Published
2014

33. Quantification de l'évapotranspiration réelle à l'échelle d'un bassin versant agropastoral du semi-aride

Author

Zitouna Chebbi, R., Prévot, L., Jacob, Frédéric, and Voltz, M.

Subjects
CULTURE, BASSIN VERSANT, BESOIN EN EAU, EVAPOTRANSPIRATION REELLE, GESTION DE L'EAU, MESURE, RESSOURCES EN EAU, MODELISATION, UTILISATION DU SOL, METHODOLOGIE, COLLINE, RELIEF
Abstract

Dans la région méditerranéenne, la connaissance des besoins en eau des cultures est primordiale, pour une gestion rationnelle des ressources en eau. L’évapotranspiration réelle (ETR) peut être estimée par plusieurs méthodes de mesures ou de modélisation. La méthode des covariances turbulentes (EC) a l’avantage de permettre la mesure directe même si des difficultés d’ordre méthodologiques sont rencontrées dans les milieux hétérogènes et collinaires. Dans l’objectif d’évaluer la variabilité de fonctionnement de la végétation d’un bassin versant durant une saison, des chroniques d’ETR mesurées pour différentes occupations de sol sont comparées. Le bassin versant "Kamech" site de l’ORE OMERE en Tunisie, caractérisé par un milieu hétérogène, a été choisi pour mettre en place des expérimentations de suivie de l’ETR depuis 2004. Des mesures atmosphériques, les différents termes du bilan d’énergie ont été réalisées, les flux turbulents sont mesurés par EC. L’expérimentation a permis d’évaluer la technique de mesure dans les conditions de relief et la méthodologie de reconstitution des flux à l’échelle d’une saison à partir de mesures discontinues dans le temps. Les comparaisons des chroniques d’ETR de céréales, de légumineuses et de parcours ont montré la dynamique des échanges surface-atmosphère d’un bassin versant collinaire du semi aride

Published
2014

35. Ontology and the Lexicon: A Multidisciplinary Perspective

Author

Prévot L., Chu-ren Huang, Calzolari N., Gangemi A., Lenci A., and Oltramari A.

Subjects
Ontology. Computational Lexicology
Abstract

The relation between ontologies and language is currently at the forefront of natural language processing (NLP). Ontologies, as widely used models in semantic technologies, have much in common with the lexicon. A lexicon organizes words as a conventional inventory of concepts, while an ontology formalizes concepts and their logical relations. A shared lexicon is the prerequisite for knowledge-sharing through language, and a shared ontology is the prerequisite for knowledge-sharing through information technology. In building models of language, computational linguists must be able to accurately map the relations between words and the concepts that they can be linked to. This book focuses on the technology involved in enabling integration between lexical resources and semantic technologies. It will be of interest to researchers and graduate students in NLP, computational linguistics, and knowledge engineering, as well as in semantics, psycholinguistics, lexicology and morphology/syntax.

Published
2010

37. Developing International Standards of Language Resources for Semantic Web Applications - Research Report of the International Joint Research Program NEDO

Author

Tokunaga T., Calzolari N., Huang C., Kiyoaki S., Sornlertlamvanich V., Yingju X., Charoenporn T., Chung S., Hsieh S., Kaplan D., Monachini M., Prévot L., and Soria C.

Subjects
International standards, Language resources, Semantic web applications
Abstract

This report describes a three-year project aiming at an international standard for language resources that includes Asian languages. We summarise our contribution to an international standard of lexical markup framework (LMF) and introduce a prototype query expansion system using LMF-compliant lexical resources. Since ISO 24613 was in the FDIS stage and fairly stable, we built sample lexicons in Chinese, English, Italian, Japanese, and Thai based on ISO24613. At the same time, we implemented a query expansion system utilising rich linguistic resources including lexicons described in the ISO 24613 framework. We confirmed that a system was feasible which worked on the tested languages (including both Western and Eastern languages) when given lexicons are compliant with the framework.

Published
2008

43. Photometric constraints on microlens spectroscopy of EROS-BLG-2000-5

Author

Alfonso, C., Albert, J. N., Andersen, J., Ansari, R., Aubourg, É, Bareyre, P., Bauer, F., Blanc, G., Bouquet, A., Char, S., Charlot, X., Couchot, F., Coutures, C., Derue, F., Ferlet, R., Fouqué, P., Glicenstein, J. F., Goldman, B., Gould, A., Graff, D., Gros, M., Haïssinski, J., Hamilton, J. C., Hardin, D., Kat, J., Kim, A., Lasserre, T., Leguillou, L., Lesquoy, É, Loup, C., Magneville, C., Mansoux, B., Marquette, J. B., Maurice, É, Milsztajn, A., Moniez, M., Nathalie Palanque-Delabrouille, Perdereau, O., Prévot, L., Regnault, N., Rich, J., Spiro, M., Vidal-Madjar, A., Vigroux, L., Zylberajch, S., Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de l'Accélérateur Linéaire (LAL), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF (institution))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Departement de recherche SPAtiale (DESPA), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), EROS, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Fouqué, Pascal

Subjects
Physics, Microlens, Photosphere, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Radius, Atmospheric model, [SDU.ASTR] Sciences of the Universe [physics]/Astrophysics [astro-ph], 01 natural sciences, Spectral line, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], 13. Climate action, Space and Planetary Science, [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], 0103 physical sciences, Absorption (electromagnetic radiation), Spectroscopy, 010303 astronomy & astrophysics, Chromosphere
Abstract

We apply EROS photometric data to interpret previously published Keck and VLT spectra of the binary-microlens caustic-crossing event EROS-BLG-2000-5. We show that the VLT data imply that the outer 4 % of the limb of the K3-giant source is strongly in emission in Halpha, in contradiction to available models of the photosphere. This conflict could be resolved if the integrated Halpha emission from the chromosphere were equal to 8 % of the integrated Halpha absorption from the source as a whole. These conclusions regarding the extreme limb are almost completely model-independent. We also present a general method for using the photometric data to facilitate direct comparison between the atmospheric model and the spectroscopic data. While this method has some model-dependent features, it is fairly robust and can serve to guide the analysis of spectra while more detailed models of the lens geometry are being developed. In addition, we find that the color of the limb of the source (outer 5.5 % by radius) is Delta(V-I) = 0.37 redder than the source as a whole, so that it has the color of a M0 giant., Comment: 7 figures, 1 table

Published
2001

44. Modelling crop geometry using multiple view angles

Author

Vonder, O.W., Clevers, J.G.P.W., Desprats, J.F., King, C., Prévot, L., and Bruguier, N.

Subjects
Laboratory of Geo-information Science and Remote Sensing, Monitoring, Data dissemination, Calibration, Validation, Agriculture, Laboratorium voor Geo-informatiekunde en Remote Sensing, Biomass, PE&RC, Modelling
Published
2000

45. A semi-empirical approach for estimating plant parameters within the ReSeDa project

Author

Clevers, J.G.P.W., Vonder, O.W., Jongschaap, R.E.E., Desprats, J.F., King, C., Prévot, L., and Bruguier, N.

Subjects
Multi-temporal, Laboratory of Geo-information Science and Remote Sensing, Monitoring, Agriculture, Multi-spectral data, Laboratorium voor Geo-informatiekunde en Remote Sensing, PE&RC, Modelling
Published
2000

46. Observation of Microlensing towards the Galactic Spiral Arms: EROS II 3 year survey

Author

Derue, F, Afonso, C, Alard, C, Albert, J N, Andersen, J, Ansari, R, Aubourg, E, Bareyre, P, Bauer, F, Beaulieu, J P, Blanc, G, Bouquet, A, Char, S, Charlot, X, Couchot, F, Coutures, C, Ferlet, R, Fouqué, P, Glicenstein, J F, Goldman, B, Gould, A, Graff, D, Gros, M H, Haïssinski, J, Hamilton, J C, Hardin, D, De Kat, J, Kim, A, Lasserre, T, Le Guillou, Laurent, Lesquoy, E, Loup, C, Magneville, C, Mansoux, B, Marquette, J B, Maurice, E, Milsztajn, A, Moniez, M, Palanque-Delabrouille, Nathalie, Perdereau, O, Prévot, L, Regnault, N, Rich, J, Spiro, Michel, Vidal-Madjar, A, Vigroux, L, and Zylberajch, S

Subjects
Astrophysics and Astronomy
Published
2000

47. ERS and Radarsat images for land use classification at a regional scale: some possibilities for future A-SAR configuration

Author

Desprats, J.F., Borne, Frédéric, King, C., Bégué, Agnès, Prévot, L., Baghdadi, Nicolas, and Bourguignon, A.

Subjects
Utilisation des terres, Radar, Télédétection, Planification régionale, E11 - Économie et politique foncières, Satellite, U30 - Méthodes de recherche, Plante annuelle
Abstract

A possible output of the European project ReSeDA is to use the very complete available data base covering one year of the growing season for assessing the interest of multi-angular time series of radar images (Baret & al, 1999). The aim is to prepare an optimal use of A-SAR data for the purpose of regional agricultural statistics on a site representative of semi-irrigated areas. Four sets of time series of SAR data have been compared in the perspective of operational assessment: 3 dates of ERS2, 3 dates of Radarsat, 6 dates of bi-angular ERS and Radarsat, and 9 dates of ERS. Two filters and a software of segmentation of images (PAPRI from CIRAD) have been successively applied over the 4 sets. The results of classification are compared with the reference plots of the test site Alpilles for 3 major annual crops (wheat, maize and sunflower). Then the robustness of the best discrimination is tested at a regional scale through 12 external segments of 700x700 m, according to the well known sampling system of the european MARS project. The pre-segmentation of radar images and the bi-angular series of SAR improve the discrimination annual crops for assessing their areas at a regional scale. It gives robust guidelines about the interest of SAR data for the regional crop distribution in case of cloudy conditions.

Published
2000

48. EROS 2 proper motion survey: a field brown dwarf and an L dwarf companion to LHS 102

Author

Goldman, B., Delfosse, X., Forveille, T., Afonso, C., Alard, C., Albert, J. N., Andersen, J., Ansari, R., Aubourg, E., Bareyre, P., Bauer, F., Beaulieu, J. P., Borsenberger, J., Bouquet, A., Char, S., Charlot, X., Couchot, F., Coutures, C., Derue, F., Ferlet, R., Fouqué, P., Glicenstein, J. F., Gould, A., Graff, D., Gros, M., Haissinski, J., Hamilton, J. C., Hardin, D., Kat, J., Kim, A., Lasserre, T., Lesquoy, E., Loup, C., Magneville, C., Mansoux, B., Jean-Baptiste Marquette, Martin, E. L., Maurice, E., Milsztajn, A., Moniez, M., Palanque-Delabrouille, N., Perdereau, O., Prévot, L., Regnault, N., Rich, J., Spiro, M., Vidal-Madjar, A., Vigroux, L., Zylberajch, S., The Eros Collaboration, Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Observatoire de Paris - Site de Meudon (OBSPM), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF (institution))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), EROS, Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Lantz, Simone

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics
Abstract

We report the discovery of two L dwarfs (the new spectral class defined for dwarfs cooler than the M type) in a two-epoch CCD proper motion survey of 413 square degrees, complemented by infrared photometry from DENIS. One of them has a strong lithium line and is therefore a brown dwarf. The other is a common proper motion companion to the mid-M dwarf LHS 102 (GJ 1001), which has a well determined trigonometric parallax. LHS 102B is thus the coolest L dwarf of known distance and luminosity. Its infrared absolute photometry are very well reproduced by the Allard et al DUSTY models., Comment: 5 pages, LaTeX, 6 postscript figures, style correction, two spectra of the discovered objects added, coordinates of the LHS102 pair corrected

Published
1999

50. Absolute magnitude and kinematics of Barium stars

Author

Gómez, A. E., Luri Carrascoso, Xavier, Grenier, S., Prévot, L., Mennessier, M. O., Figueras Siñol, Francesca, and Torra Roca, Jorge

Subjects
Estadística matemàtica, Mathematical statistics, Galactic kinematics, Astrophysics::Solar and Stellar Astrophysics, Cinemàtica galàctica, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Stars, Astrophysics::Galaxy Astrophysics, Estels
Abstract

The absolute magnitude of barium stars has been obtained from kinematical data using a new algorithm based on the maximum-likelihood principle. The method allows to separate a sample into groups characterized by different mean absolute magnitudes, kinematics and z-scale heights. It also takes into account, simultaneously, the censorship in the sample and the errors on the observables. The method has been applied to a sample of 318 barium stars. Four groups have been detected. Three of them show a kinematical behaviour corresponding to disk population stars. The fourth group contains stars with halo kinematics. The luminosities of the disk population groups spread a large range. The intrinsically brightest one (M_v_=-1.5mag, σ_M_=0.5mag) seems to be an inhomogeneous group containing barium binaries as well as AGB single stars. The most numerous group (about 150 stars) has a mean absolute magnitude corresponding to stars in the red giant branch (M_v_=0.9mag, σ_M_=0.8mag). The third group contains barium dwarfs, the obtained mean absolute magnitude is characteristic of stars on the main sequence or on the subgiant branch (M_v_=3.3mag, σ_M_=0.5mag). The obtained mean luminosities as well as the kinematical results are compatible with an evolutionary link between barium dwarfs and classical barium giants. The highly luminous group is not linked with these last two groups. More high-resolution spectroscopic data will be necessary in order to better discriminate between barium and non-barium stars.

Published
1997

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