المؤلفون: Hafsia, Sarah, Haramboure, Marion, Wilkinson, David Arthur, Baldet, Thierry, Yemadje-Menudier, Luce, Vincent, Muriel, Tran, Annelise, Atyame, Célestine M., Mavingui, Patrick

المصدر: PLoS Neglected Tropical Diseases

مصطلحات موضوعية: S50 - Santé humaine, C30 - Documentation et information, Virose, Maladie transmise par vecteur, Aedes, Enquête pathologique, Transmission des maladies, Relevé (des données), Histoire, http://aims.fao.org/aos/agrovoc/c_8260Test, http://aims.fao.org/aos/agrovoc/c_34142Test, http://aims.fao.org/aos/agrovoc/c_146Test, http://aims.fao.org/aos/agrovoc/c_28665Test, http://aims.fao.org/aos/agrovoc/c_2329Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_3635Test, http://aims.fao.org/aos/agrovoc/c_3828Test, http://aims.fao.org/aos/agrovoc/c_1790Test, http://aims.fao.org/aos/agrovoc/c_4510Test, http://aims.fao.org/aos/agrovoc/c_4662Test, http://aims.fao.org/aos/agrovoc/c_4665Test, http://aims.fao.org/aos/agrovoc/c_7017Test, http://aims.fao.org/aos/agrovoc/c_6543Test

جغرافية الموضوع: océan Indien, Comores, Maurice, Mayotte, Seychelles, Réunion

الوقت: Madagascar

الوصف: Background: Dengue is the world's most prevalent mosquito-borne viral disease. It is endemic in many tropical and subtropical countries and represents a significant global health burden. The first reports of dengue virus (DENV) circulation in the South West Indian Ocean (SWIO) islands date back to the early 1940s; however, an increase in DENV circulation has been reported in the SWIO in recent years. The aim of this review is to trace the history of DENV in the SWIO islands using available records from the Comoros, Madagascar, Mauritius, Mayotte, Seychelles, and Reunion. We focus in particular on the most extensive data from Reunion Island, highlighting factors that may explain the observed increasing incidence, and the potential shift from one-off outbreaks to endemic dengue transmission. Methods: Following the PRISMA guidelines, the literature review focused queried different databases using the keywords “dengue” or “Aedes albopictus” combined with each of the following SWIO islands the Comoros, Madagascar, Mauritius, Mayotte, Seychelles, and Reunion. We also compiled case report data for dengue in Mayotte and Reunion in collaboration with the regional public health agencies in these French territories. References and data were discarded when original sources were not identified. We examined reports of climatic, anthropogenic, and mosquito-related factors that may influence the maintenance of dengue transmission independently of case importation linked to travel. Findings and conclusions: The first report of dengue circulation in the SWIO was documented in 1943 in the Comoros. Then not until an outbreak in 1976 to 1977 that affected approximately 80% of the population of the Seychelles. DENV was also reported in 1977 to 1978 in Reunion with an estimate of nearly 30% of the population infected. In the following 40-year period, DENV circulation was qualified as interepidemic with sporadic cases. However, in recent years, the region has experienced uninterrupted DENV transmission at elevated incidence. Since ...

وصف الملف: text

العلاقة: http://agritrop.cirad.fr/601627Test/; Overview of dengue outbreaks in the southwestern Indian Ocean and analysis of factors involved in the shift toward endemicity in Reunion Island: A systematic review. Hafsia Sarah, Haramboure Marion, Wilkinson David Arthur, Baldet Thierry, Yemadje-Menudier Luce, Vincent Muriel, Tran Annelise, Atyame Célestine M., Mavingui Patrick. 2022. PLoS Neglected Tropical Diseases, 16 (7):e0010547, 16 p.https://doi.org/10.1371/journal.pntd.0010547Test; http://agritrop.cirad.fr/601627/1/Publi%20Overview%20on%20dengue%20in%20SWIO%20Hafsia_PlosNTD%202022.pdfTest

الإتاحة: https://doi.org/10.1371/journal.pntd.0010547Test
http://agritrop.cirad.fr/601627Test/
http://agritrop.cirad.fr/601627/1/Publi%20Overview%20on%20dengue%20in%20SWIO%20Hafsia_PlosNTD%202022.pdfTest

المؤلفون: Leroux, Louise, Falconnier, Gatien N., Diouf, Abdoul Aziz, Ndao, Babacar, Gbodjo, Jean Eudes, Tall, Laure, Balde, Alpha Bocar, Clermont-Dauphin, Cathy, Bégué, Agnès, Affholder, François, Roupsard, Olivier

المصدر: Agricultural Systems

مصطلحات موضوعية: F08 - Systèmes et modes de culture, Faidherbia albida, agroforesterie, rendement des cultures, contrôle continu, évaluation, télédétection, relevé (des données), agriculture familiale, exploitation agricole familiale, http://aims.fao.org/aos/agrovoc/c_10734Test, http://aims.fao.org/aos/agrovoc/c_207Test, http://aims.fao.org/aos/agrovoc/c_10176Test, http://aims.fao.org/aos/agrovoc/c_2736Test, http://aims.fao.org/aos/agrovoc/c_330990Test, http://aims.fao.org/aos/agrovoc/c_6498Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_1422957329186Test, http://aims.fao.org/aos/agrovoc/c_2787Test, http://aims.fao.org/aos/agrovoc/c_6970Test

جغرافية الموضوع: Sénégal

الوصف: Agroforestry is pointed out by the Intergovernmental Panel on Climate Change report as a key option to respond to climate change and land degradation while simultaneously improving global food security (IPCC, 2019). Faidherbia albida parklands are widespread in Sub-Saharan Africa and provide several ecosystem services to populations, notably an increase in crop productivity. While remote sensing has been proven useful for crop yield assessment in smallholder farming system, it has so far ignored the woody component. We propose an original approach combining remote sensing, landscape ecology and statistical modelling to i) improve the accuracy of millet yield prediction in parklands and ii) identify the main drivers of millet yield spatial variation. The parkland of Central Senegal was chosen as a case study. Firstly, we calibrated a remote sensing-based linear model that accounted for vegetation productivity and tree density to predict millet yield. Integrating parkland structure improved the accuracy of yield estimation. The best model based on a combination of Green Difference Vegetation Index and number of trees in the field explained 70% of observed yield variability (relative Root Mean Squared Error (RRMSE) of 28%). The best model based solely on vegetation productivity (no information on parkland structure) explained only 46% of the observed variability (RRMSE = 34%). Secondly we investigated the drivers of the spatial variability in estimated yield using Gradient Boosting Machine algorithm (GBM) and biophysical and management factors derived from geospatial data. The GBM model explained 81% of yield spatial variability. Predominant drivers were soil nutrient availability (i.e. soil total nitrogen and total phosphorous) and woody cover in the surrounding landscape of fields. Our results show that millet yield increases with woody cover in the surrounding landscape of fields up to a woody cover of 35%. These findings have to be strengthened by testing the approach in more diversified and/or denser ...

وصف الملف: text

العلاقة: http://agritrop.cirad.fr/596325Test/; Using remote sensing to assess the effect of trees on millet yield in complex parklands of Central Senegal. Leroux Louise, Falconnier Gatien N., Diouf Abdoul Aziz, Ndao Babacar, Gbodjo Jean Eudes, Tall Laure, Balde Alpha Bocar, Clermont-Dauphin Cathy, Bégué Agnès, Affholder François, Roupsard Olivier. 2020. Agricultural Systems, 184:102918, 13 p.https://doi.org/10.1016/j.agsy.2020.102918Test; http://agritrop.cirad.fr/596325/7/ID596325.pdfTest

الإتاحة: https://doi.org/10.1016/j.agsy.2020.102918Test
http://agritrop.cirad.fr/596325Test/
http://agritrop.cirad.fr/596325/7/ID596325.pdfTest

المؤلفون: Rumiano, Florent, Wielgus, Elodie, Miguel, Eve, Chamaille-Jammes, Simon, Valls-Fox, Hugo, Cornélis, Daniel, De Garine-Wichatitsky, Michel, Fritz, Hervé, Caron, Alexandre, Tran, Annelise

المصدر: Remote Sensing

مصطلحات موضوعية: L20 - Écologie animale, Syncerus caffer, Bos taurus, Zébu, Savane, Distribution des populations, Dynamique des populations, Télédétection, Relevé (des données), literature [EN], http://aims.fao.org/aos/agrovoc/c_d0debf2fTest, http://aims.fao.org/aos/agrovoc/c_9372Test, http://aims.fao.org/aos/agrovoc/c_8507Test, http://aims.fao.org/aos/agrovoc/c_6825Test, http://aims.fao.org/aos/agrovoc/c_6113Test, http://aims.fao.org/aos/agrovoc/c_6111Test, http://aims.fao.org/aos/agrovoc/c_6498Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_330835Test, http://aims.fao.org/aos/agrovoc/c_7252Test

جغرافية الموضوع: Afrique du Sud

الوصف: Interfaces between protected areas and their peripheries in southern Africa are subject to interactions between wildlife and livestock that vary in frequency and intensity. In these areas, the juxtaposition between production and conservation land uses in a context of increasing anthropisation can create issues associated with human-wildlife coexistence and raises concerns for biodiversity conservation, local development and livelihoods. This literature review aimed at addressing the need to consolidate and gather in one article current knowledge on potential uses of satellite remote sensing (SRS) products by movement ecologists to investigate the sympatry of wildlife/domestic ungulates in savanna interface environments. A keyword querying process of peer reviewed scientific paper, thesis and books has been implemented to identify references that (1) characterize the main environmental drivers impacting buffalo (Syncerus caffer caffer) and cattle (Bos taurus & Bos indicus) movements in southern Africa environments, (2) describe the SRS contribution to discriminate and characterize these drivers. In total, 327 references have been selected and analyzed. Surface water, precipitation, landcover and fire emerged as key drivers impacting the buffalo and cattle movements. These environmental drivers can be efficiently characterized by SRS, mainly through open-access SRS products and standard image processing methods. Applying SRS to better understand buffalo and cattle movements in semi-arid environments provides an operational framework that could be replicated in other type of interface where different wild and domestic species interact. There is, however, a need for animal movement ecologists to reinforce their knowledge of remote sensing and/or to increase pluridisciplinary collaborations.

وصف الملف: text

العلاقة: http://agritrop.cirad.fr/596613Test/; Remote sensing of environmental drivers influencing the movement ecology of sympatric wild and domestic ungulates in semi-arid savannas, a review. Rumiano Florent, Wielgus Elodie, Miguel Eve, Chamaille-Jammes Simon, Valls-Fox Hugo, Cornélis Daniel, De Garine-Wichatitsky Michel, Fritz Hervé, Caron Alexandre, Tran Annelise. 2020. Remote Sensing, 12:3218, 37 p.https://doi.org/10.3390/rs12193218Test; http://agritrop.cirad.fr/596613/1/2020%20-%20Rumiano%20-%20RS.pdfTest

الإتاحة: https://doi.org/10.3390/rs12193218Test
http://agritrop.cirad.fr/596613Test/
http://agritrop.cirad.fr/596613/1/2020%20-%20Rumiano%20-%20RS.pdfTest

المؤلفون: Ndamiyehe Ncutirakiza, Jean-Baptiste, Lejeune, Philippe, Gourlet-Fleury, Sylvie, Fayolle, Adeline, Ndjele Mianda-Bungi, Léopold, Ligot, Gauthier

المصدر: Bois et Forêts des Tropiques

مصطلحات موضوعية: F62 - Physiologie végétale - Croissance et développement, K01 - Foresterie - Considérations générales, U30 - Méthodes de recherche, Arbre forestier, accroissement forestier, Houppier, Biomasse aérienne, Accroissement du diamètre, Mesure, télémétrie, Relevé (des données), Relevé aérien, Croissance, Technique analytique, http://aims.fao.org/aos/agrovoc/c_3052Test, http://aims.fao.org/aos/agrovoc/c_c0e4ff0eTest, http://aims.fao.org/aos/agrovoc/c_16172Test, http://aims.fao.org/aos/agrovoc/c_1373987580598Test, http://aims.fao.org/aos/agrovoc/c_34812Test, http://aims.fao.org/aos/agrovoc/c_4668Test, http://aims.fao.org/aos/agrovoc/c_24134Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_156Test, http://aims.fao.org/aos/agrovoc/c_3394Test, http://aims.fao.org/aos/agrovoc/c_1513Test, http://aims.fao.org/aos/agrovoc/c_8500Test

جغرافية الموضوع: République démocratique du Congo

الوصف: Caractériser la dynamique d'une forêt est essentiel pour la gestion forestière. Les houppiers des arbres forment un élément clé de cette dynamique ; mais, en forêt tropicale, les mesurer n'est pas simple. Cette étude teste l'utilisation d'images aériennes à haute résolution pour estimer la croissance diamétrique des arbres, en intégrant des mesures fines des houppiers détectés. Des ortho-images de 10 cm/pixel de résolution ont été obtenues à l'aide d'un drone à aile fixe sur une parcelle de 9 ha, installée dans la forêt de Yoko en République démocratique du Congo. Les inventaires menés sur les arbres de DHP ≥10 cm en 2008 et en 2016 ont permis d'avoir accès à différentes caractéristiques dendrométriques individuelles, dont le diamètre des arbres et leur tempérament, et de calculer des accroissements diamétriques. Des modèles linéaires mixtes ont été calibrés pour prédire l'accroissement de 163 arbres identifiés à la fois sur le terrain et sur les ortho-images en utilisant les variables quantifiées uniquement sur le terrain et/ou à partir de variables mesurées sur les ortho-images. Les images aériennes ont permis de détecter 23,4 % des arbres de DHP ≥10 cm inventoriés au sol, et représentant 75,1 % de la biomasse aérienne du peuplement. La probabilité de détection des arbres a varié en fonction de leur DHP : de 0,09 pour les arbres de DHP < 30 cm à 0,97 pour les arbres de DHP ≥60 cm. Les variables quantifiées par télédétection ajoutées aux variables de terrain ont permis d'améliorer significativement la prédiction de l'accroissement diamétrique. Les meilleurs modèles d'estimation des accroissements diamétriques contiennent notamment un terme caractérisant la dimension du houppier des arbres qui n'a pu être mesuré que par télédétection. Parmi les variables déterminées par télédétection, la superficie convexe du houppier est apparue la plus performante dans les modèles, et s'avère ainsi être la mesure la plus intéressante pour décrire la compétition entre les houppiers. Ces résultats ouvrent des perspectives ...

وصف الملف: text

العلاقة: http://agritrop.cirad.fr/595471Test/; Quantifier les dimensions des houppiers à l'aide d'images aériennes à haute résolution pour estimer l'accroissement diamétrique des arbres dans les forêts d'Afrique centrale. Ndamiyehe Ncutirakiza Jean-Baptiste, Lejeune Philippe, Gourlet-Fleury Sylvie, Fayolle Adeline, Ndjele Mianda-Bungi Léopold, Ligot Gauthier. 2020. Bois et Forêts des Tropiques, 343 : 67-81.https://doi.org/10.19182/bft2020.343.a31848Test; http://agritrop.cirad.fr/595471/1/595471.pdfTest

الإتاحة: https://doi.org/10.19182/bft2020.343.a31848Test
http://agritrop.cirad.fr/595471Test/
http://agritrop.cirad.fr/595471/1/595471.pdfTest

المؤلفون: Wang, Xueqiang, Blanken, Peter D., Kasemsap, Poonpipope, Petchprayoon, Pakorn, Thaler, Philippe, Nouvellon, Yann, Gay, Frédéric, Chidthaisong, Amnat, Sanwangsri, Montri, Chayawat, Chompunut, Chantuma, Pisamai, Sathornkich, Jate, Kaewthongrach, Rungnapa, Satakhun, Duangrat, Phattaralerphong, Jessada

المصدر: Journal of Geophysical Research: Biogeosciences

مصطلحات موضوعية: K10 - Production forestière, P01 - Conservation de la nature et ressources foncières, Plantations, Grande exploitation, Hévéa, Hevea brasiliensis, forêt primaire, Analyse de covariance, Méthode statistique, Relevé (des données), Carbone, Bilan hydrique du sol, http://aims.fao.org/aos/agrovoc/c_5990Test, http://aims.fao.org/aos/agrovoc/c_15904Test, http://aims.fao.org/aos/agrovoc/c_3588Test, http://aims.fao.org/aos/agrovoc/c_3589Test, http://aims.fao.org/aos/agrovoc/c_28112Test, http://aims.fao.org/aos/agrovoc/c_28833Test, http://aims.fao.org/aos/agrovoc/c_7377Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_1301Test, http://aims.fao.org/aos/agrovoc/c_7206Test, http://aims.fao.org/aos/agrovoc/c_4073Test, http://aims.fao.org/aos/agrovoc/c_12076Test, http://aims.fao.org/aos/agrovoc/c_1155Test, http://aims.fao.org/aos/agrovoc/c_7701Test, http://aims.fao.org/aos/agrovoc/c_8227Test, envir, geo

جغرافية الموضوع: Cambodge, République démocratique populaire lao, Myanmar, Thaïlande, Viet Nam

الوصف: Rubber plantations have rapidly replaced natural forests (NFs) in Mainland Southeast Asia, yet the relevant impacts on the terrestrial carbon cycle remain uncertain especially with an increase in drought frequency. Our study compared eddy-covariance measurements of carbon and water fluxes from two rubber monoculture plantations (at a northern marginal site and a southern traditional plantation site) with a second-growth NF between 2015 and 2018, and their responses to a prolonged drought during 2015/2016. The NF had higher light use efficiency, water use efficiency and gross primary productivity (GPP, 2.94 ± 0.41 kg C m−2 yr−1) than the northern rubber (NR) monoculture (2.45 ± 0.17 kg C m−2 yr−1), while lower ecosystem carbon use efficiency (eCUE) caused a lower net ecosystem productivity (NEP, 0.75 ± 0.25 kg C m−2 yr−1) compared to the plantation (1.19 ± 0.22 kg C m−2 yr−1). Drought decreased the NF eCUE by 23% with significant carbon uptake restrictions across multiple seasons, while the rubber GPP reduction was only substantial in the warm-dry season with an overall 17% decline in eCUE. The NR site's GPP was mainly controlled by soil water content throughout the year. Higher light availability offset the negative effect of drier conditions on the rubber GPP, resulting in larger carbon uptake compared to the southern plantation (GPP, 2.12 ± 0.12 kg C m−2 yr−1; NEP, 1.07 ± 0.14 kg C m−2 yr−1). In contrast, the NF GPP was mainly restricted by vapor pressure deficit, especially during the drought.

العلاقة: http://agritrop.cirad.fr/600978/1/Wang%202022%20c%20and%20water%20cycling%20in%20rubber%20plantations%20and%20forest%20in%20Thailand.pdfTest; http://agritrop.cirad.fr/600978Test/

الإتاحة: http://agritrop.cirad.fr/600978/1/Wang%202022%20c%20and%20water%20cycling%20in%20rubber%20plantations%20and%20forest%20in%20Thailand.pdfTest
http://agritrop.cirad.fr/600978Test/

المؤلفون: Motisi, Natacha, Papaïx, Julien, Poggi, Sylvain

المصدر: Phytopathology

مصطلحات موضوعية: H20 - Maladies des plantes, F08 - Systèmes et modes de culture, Coffea arabica, Colletotrichum, Agroforesterie, Ombrage, Morbidité, Modélisation, Méthode statistique, Théorie bayésienne, Relevé (des données), http://aims.fao.org/aos/agrovoc/c_1721Test, http://aims.fao.org/aos/agrovoc/c_1761Test, http://aims.fao.org/aos/agrovoc/c_207Test, http://aims.fao.org/aos/agrovoc/c_7020Test, http://aims.fao.org/aos/agrovoc/c_4936Test, http://aims.fao.org/aos/agrovoc/c_230ab86cTest, http://aims.fao.org/aos/agrovoc/c_7377Test, http://aims.fao.org/aos/agrovoc/c_28840Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_1229Test, envir, psy

جغرافية الموضوع: Cameroun

الوصف: Coffee berry disease (CBD) can cause significant coffee yield losses along with major income losses for African smallholders. Although these farmers cannot afford to purchase pesticides to control the disease, agroecological solutions have rarely been investigated, and how epidemiological mechanisms are linked to the environment of the coffee tree and the plot remains unclear. Agroforestry systems are a promising agroecological option, but the effect of shade on CBD regulation is the subject of debate, and the use of plant species diversity remains uncertain. Here, we address how shade affects epidemiological mechanisms by modifying the microclimate. For this purpose, we developed a mechanistic susceptible-exposed-infectious-removed (SEIR) model, and used a Bayesian framework to infer the epidemiological parameters against microclimatic covariates. We show that shade has opposing effects on different epidemiological mechanisms. Specifically, shade can limit disease dynamics by reducing disease transmission while simultaneously promoting disease dynamics by reducing the latent period of the pathogen. However, in full sun, efficient disease transmission compensates for long latent periods. As a result, the balances between microclimatic variables can counterbalance the epidemiological rates, which can dramatically alter the fate of epidemics in shade versus full sun conditions. We propose research avenues to help design cost- and environmentally effective management strategies for CBD that are notably based on the functional traits of shade trees that could hamper CBD dispersal.

العلاقة: http://agritrop.cirad.fr/600293/7/600293.pdfTest; http://agritrop.cirad.fr/600293Test/

الإتاحة: http://agritrop.cirad.fr/600293/7/600293.pdfTest
http://agritrop.cirad.fr/600293Test/

المؤلفون: Groth, Andreas, Ghil, Michael, Hallegatte, Stéphane, Dumas, Patrice

المصدر: OECD Journal: Journal of Business Cycle Measurement and Analysis

مصطلحات موضوعية: E10 - Économie et politique agricoles, U30 - Méthodes de recherche, 000 - Autres thèmes, politique agricole, modèle mathématique, méthode statistique, relevé (des données), économie agricole, http://aims.fao.org/aos/agrovoc/c_201Test, http://aims.fao.org/aos/agrovoc/c_24199Test, http://aims.fao.org/aos/agrovoc/c_7377Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_8672Test, http://aims.fao.org/aos/agrovoc/c_8114Test

جغرافية الموضوع: États-Unis d'Amérique

الوصف: We apply multivariate singular spectrum analysis to the study of US business cycle dynamics. This method provides a robust way to identify and reconstruct oscillations, whether intermittent or modulated. We show such oscillations to be associated with comovements across the entire economy. The problem of spurious cycles generated by the use of detrending filters is addressed and we present a Monte Carlo test to extract significant oscillations. The behavior of the US economy is shown to change significantly from one phase of the business cycle to another: the recession phase is dominated by a five-year mode, while the expansion phase exhibits more complex dynamics, with higher-frequency modes coming into play. We show that the variations so identified cannot be generated by random shocks alone, as assumed in "real" business-cycle models, and that endogenous, deterministically generated variability has to be involved.

وصف الملف: text

العلاقة: http://agritrop.cirad.fr/586759Test/; The role of oscillatory modes in US business cycles. Groth Andreas, Ghil Michael, Hallegatte Stéphane, Dumas Patrice. 2015. OECD Journal: Journal of Business Cycle Measurement and Analysis, 2015 (1) : 63-81.https://doi.org/10.1787/jbcma-2015-5jrs0lv715wlTest; http://agritrop.cirad.fr/586759/1/M_SSA-EBCs_final_JBCMA_188.pdfTest

الإتاحة: https://doi.org/10.1787/jbcma-2015-5jrs0lv715wlTest
http://agritrop.cirad.fr/586759Test/
http://agritrop.cirad.fr/586759/1/M_SSA-EBCs_final_JBCMA_188.pdfTest

المؤلفون: Houlès, Vianney, El Hajj, Mahmoud, Bégué, Agnès

المصدر: Symposium of ISPRS Commission I, from Sensors to Imagery = Symposium de la commission I de l'ISPRS, des capteurs à l'imagerie, 3-6 july 2006, Marne la Vallée, 3-6 july 2006

مصطلحات موضوعية: U30 - Méthodes de recherche, télédétection, altération atmosphérique, normalisation, satellite, Réflectance, relevé (des données), mesure (activité), facteur du milieu, http://aims.fao.org/aos/agrovoc/c_6498Test, http://aims.fao.org/aos/agrovoc/c_8343Test, http://aims.fao.org/aos/agrovoc/c_7366Test, http://aims.fao.org/aos/agrovoc/c_14093Test, http://aims.fao.org/aos/agrovoc/c_28538Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_4668Test, http://aims.fao.org/aos/agrovoc/c_2594Test, http://aims.fao.org/aos/agrovoc/c_6543Test, http://aims.fao.org/aos/agrovoc/c_3081Test

جغرافية الموضوع: La Réunion, France

الوصف: Les séries d'images acquises à hautes résolutions spatiale et temporelle sont une source de données importante pour les applications agricoles. Pour une utilisation quantitative de ces données, l'étape de normalisation radiométrique est indispensable. Dans ce travail, une méthode de normalisation à partir de points invariants a été comparée à des corrections atmosphériques sur une série d'images SPOT issues de la base de données ISLE-Réunion (CNES). La méthode des invariants consiste à isoler des points de l'image ayant une réflectance constante au cours du temps et à établir grâce à ces points des droites de calibration entre une date de référence et les autres dates. Les corrections atmosphériques ont été effectuées avec le modèle SMAC et des données atmosphériques d'AERONET. D'autres facteurs intervenant dans la correction des images ont également été étudiés: la pente du terrain, les coefficients d'étalonnage radiométrique et l'environnement dans le cas où une correction atmosphérique est effectuée. Les résultats montrent que les effets de l'atmosphère sont les plus importants, conduisant à des augmentations de NDVI d'environ 0.09. La correction basée sur les points invariants se traduit par une augmentation d'environ 0.03 du NDVI, mais cette valeur est liée au choix de la date de référence. Par conséquent, la comparaison doit être effectuée en calculant les variations relatives du NDVI d'une date à l'autre. Les deux méthodes montrent des différences qui pourraient être significatives lors du calcul d'indicateurs phénologiques ou de production tels que la date du maximum de NDVI ou son intégrale dans le temps.

وصف الملف: application/pdf

العلاقة: http://agritrop.cirad.fr/533726Test/; Radiometric normalization of a spot 4 and spot 5 time series of images (Isle-Reunion) for agriculture applications. Houlès Vianney, El Hajj Mahmoud, Bégué Agnès. 2006. In : Symposium of ISPRS Commission I, from Sensors to Imagery = Symposium de la commission I de l'ISPRS, des capteurs à l'imagerie, 3-6 july 2006, Marne la Vallée, 3-6 july 2006. ISPRS. s.l. : s.n., 6 p. Symposium of ISPRS from Sensors to Imagery, Marne-la-Vallée, France, 3 Juillet 2006/6 Juillet 2006.; http://agritrop.cirad.fr/533726/1/document_533726.pdfTest

الإتاحة: http://agritrop.cirad.fr/533726Test/
http://agritrop.cirad.fr/533726/1/document_533726.pdfTest
http://catalogue-bibliotheques.cirad.fr/cgi-bin/koha/opac-detail.pl?biblionumber=192501Test

المؤلفون: Fok, Michel

المصدر: Cotton production for the new millennium. Proceedings of the World Cotton research Conference, 3, Cape Town, South Africa, 9-13 March, 2003

مصطلحات موضوعية: E10 - Économie et politique agricoles, E70 - Commerce, commercialisation et distribution, coton, petite exploitation agricole, relevé (des données), productivité, coût de production, analyse économique, http://aims.fao.org/aos/agrovoc/c_1926Test, http://aims.fao.org/aos/agrovoc/c_7113Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_6210Test, http://aims.fao.org/aos/agrovoc/c_6202Test, http://aims.fao.org/aos/agrovoc/c_2469Test, http://aims.fao.org/aos/agrovoc/c_166Test

جغرافية الموضوع: Afrique au sud du Sahara

الوصف: Countries in Sub-Saharan Africa (SSA) alone only contribute to a limited share of world cotton production, but when added to production from Froncophone Africa Countries (FAC) their share of world exports is very significant, globally ranking second after the USA with 75% of the exported volume, Existing figures, albeit incomplete, provide evidence that FAC's cotton is among the most competitive in the world. This achievement is further noteworthy since the FAC's production does not benefit from any subsidy, while positive socio and economic impacts associated with cotton production have been emphasized by numerous academic works. The maintenance of, if not increasing, subsidy support to cotton production in many cottonproducing countries is challenging the sustainability of cotton in SSA, Correction of this current iniquifous situation needs to be contemplated through international negotiations the outcomes of which remain uncertain. In addition internal efforts must be implemented with a view of further increases in productivity arid competitiveness. This paper explores progress and challenges in making productivity gains at the field level based on data obtained from surveys implemented in Mali, Benin and Mozambique, representing countries with different backgrounds in cotton crop intensification. Compared to World average, yields currently achieved in SSA countries rank from above average to low and this range of the yield distribution is related to input use, the level of which is often for below the one encountered in many other cotton producing countries. However yields obtained by the best farmers can be for above the World overage and may be close to the best ones under rainfed conditions, The gap between the best former yield level and the overage yields in SSA countries is an indicator of the potential margins within which progress could be made in making productivity gains under the existing production techniques. Significant productivity gain is possible from existing techniques, as well as with ...

وصف الملف: text

العلاقة: http://agritrop.cirad.fr/520556Test/; Progress and challenges in making productivity gains in cotton production by smallholders in Sub-Saharan Africa (SSA). Fok Michel. 2004. In : Cotton production for the new millennium. Proceedings of the World Cotton research Conference, 3, Cape Town, South Africa, 9-13 March, 2003. A. Swanepoel (ed.). Pretoria : ARC-IIC, 1514-1530. World Cotton Research Conference. 3, Cape Town, Afrique du Sud, 9 Mars 2003/13 Mars 2003.; http://agritrop.cirad.fr/520556/1/ID520556.pdfTest

الإتاحة: http://agritrop.cirad.fr/520556Test/
http://agritrop.cirad.fr/520556/1/ID520556.pdfTest
http://catalogue-bibliotheques.cirad.fr/cgi-bin/koha/opac-detail.pl?biblionumber=181804Test

المؤلفون: Sow, Ahmadou, Seye, Djiby, Faye, Emile, Benoit, Laure, Galan, Maxime, Haran, Julien, Brévault, Thierry

المصدر: Crop Protection

مصطلحات موضوعية: H10 - Ravageurs des plantes, F08 - Systèmes et modes de culture, millet, Lepidoptera, Noctuidae, Agroforesterie, Lutte antiravageur, Biodiversité, services écosystémiques, Animal insectivore, Oiseau, Chiroptera, Relevé (des données), systèmes agroforestiers, http://aims.fao.org/aos/agrovoc/c_4838Test, http://aims.fao.org/aos/agrovoc/c_4268Test, http://aims.fao.org/aos/agrovoc/c_12842Test, http://aims.fao.org/aos/agrovoc/c_207Test, http://aims.fao.org/aos/agrovoc/c_5726Test, http://aims.fao.org/aos/agrovoc/c_33949Test, http://aims.fao.org/aos/agrovoc/c_1348040570280Test, http://aims.fao.org/aos/agrovoc/c_11796Test, http://aims.fao.org/aos/agrovoc/c_935Test, http://aims.fao.org/aos/agrovoc/c_1560Test, http://aims.fao.org/aos/agrovoc/c_7536Test, http://aims.fao.org/aos/agrovoc/c_330982Test, http://aims.fao.org/aos/agrovoc/c_6970Test, http://aims.fao.org/aos/agrovoc/c_166Test, envir, geo

جغرافية الموضوع: Sénégal, Afrique au sud du Sahara

الوصف: A better understanding of environmental factors driving natural pest regulation is a major challenge for designing sustainable cropping systems. The objective of the present study was to assess the association between vegetation openness in traditional tree-crop agroforestry systems in Senegal, richness and abundance of vertebrates including insectivorous birds and bats, and their contribution to the natural regulation of crop pests. The millet head miner (MHM), Heliocheilus albipunctella (Lepidoptera, Noctuidae), a major constraint to increasing millet crop productivity in sub-Saharan Africa, was selected as a model system. Ten sites separated by at least one km from each other were selected in a 100 km2 study area in the Peanut basin in Senegal. In each site, a pair of millet fields distant from at least 100 m each was selected according to a gradient of vegetation openness within a 100-m radius buffer with sampling plot (5 × 5 m) at the center. Nine insectivorous bird and bat species were recorded in millet fields over the 2017 cropping season and their predator status was confirmed by direct observation or DNA detection in fecal samples. Grain losses were reduced when panicles were accessible to birds and bats, confirming their net contribution to pest regulation. At a local scale, tree diversity and vegetation openness were important predictors of the abundance of insectivorous village weaver birds and grey-headed sparrows, respectively. Some tree species (soapberry trees and neems) indirectly contributed to natural regulation of the MHM likely by providing refuges to insectivorous vertebrates whereas other tree species (baobabs) provided disservices as possible refuges for the MHM moths. Further research is needed to better understand relationships between tree cover, food web interactions and natural pest suppression, so that specific conservation measures such as habitat management can be designed to improve pest control.

العلاقة: http://agritrop.cirad.fr/595450/1/595450.pdfTest; http://agritrop.cirad.fr/595450Test/

الإتاحة: http://agritrop.cirad.fr/595450/1/595450.pdfTest
http://agritrop.cirad.fr/595450Test/