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Une analyse des espèces végétales (Isoberlinia doka, Vitellaria paradoxa, Pterocarpus erinaceus, Detarium microcarpus, Daniella oliveri, Parkia biglobosa, Andropogon gayanus, Elymandra androphila, Andropogon pseudrapricus, Pennissetum redicellatum), localisées dans la zone test située entre .le Fié et le Sankarani (affluents du fleuve Niger au Mali), est effectuée à partir d'une campagne d'opérations de terrain. L'étude des variations saisonnières et de la phénologie de ces différentes espèces permet de faire une optimisation des dates d'acquisition des données de télédétection pour la réalisation du suivi des écosystèmes. Abstract. An analysis of vegetal species (Isoberlinia doka; Vitellaria paradoxa, Pterocarpus erinaceus, Detarium microcarpus, Daniella oliveri, Parkia biglobosa, Andropogon gayanus, Elymandra androphila, Andropogon pseudrapricus, Pennissetum redicellatum) localized between the Fié and the Sankarani (both tributaries of the Niger republic of Mali) is affected through a field work campaign. A study for seasonal variations and for the phenology of different species leads to the definition of optimum remote sensing data acquisitions. Hence, the folIow-up of ecosystems can be undertaken. Le choix de la (ou des) période (s) d'acquisition des données de télédétection relatives aux régions tropicales nécessite une connaissance approfondie des périodes d'activité du tapis végétal et des espèces herbacées et ligneuses qui le composent. Ainsi, la phénologie est établie pour chaque espèce (arbres, arbustes) existant dans la région d'étude fig.(1). Elle témoigne de l'ajustement très fin de l'activité métabolique aux variations du milieu et apparaît donc comme un indicateur des conditions écologiques immédiates. En zone tropicale, les observations phénologiques de longue durée sont rares. Les informations concernant l'évolution de quelques espèces sont élaborées avec la collaboration des notables des différents villages de la région d'étude et à partir des documents disponibles réf (5). Quelques caractéristiques principales des espèces étudiées ont été également repérées.
OBJECTIFS ET CONTEXTE Les paysages végétaux du Pays dogon (Mali) en zone soudano-sahélienne correspondent presque partout à des parcs arborés à vocation agroforestière, fortement anthropisés par la sélection des arbres dans les champs. Le site de plaine de Sadia étudié ici (fig 1) est caractérisé par une vallée de piémont (Guringin) drainant les écoulements saisonniers issus du plateau gréseux, dans une gouttière (dépression périphérique) parallèle à la « falaise » de Bandiagara et qui se perdent rapidement à l'aval dans les formations sableuses dunaires de la plaine du Séno. Les différents chenaux de crue, bordés par une ripisylve, sont incisés dans une basse terrasse dominée par une terrasse supérieure (Lespez et al 2009) passant à des formations sableuses organisées en dunes linéaires vers la « falaise » et simples épandages vers le sud-est. Cette transition géomorphologique marque aussi une limite entre deux types de parcs agroforestiers, peu dense en ligneux et principaleme...
2009 •
Papeles De Geografia
Sig, teledetection et evaluation de risque d’incendie de forets «exemple du massif forestier khezana (province de Chaouene)»2012 •
The creation of protected areas was intended to counter the advance of the agricultural front and other forms of pressure on natural ecosystems, but today these pressures strongly affect these protected areas. The dynamics of the vegetation was studied in Trois Rivières forest reserve in northeastern Benin, based on Remote Sensing and GIS techniques. This study aims to analyse the vegetation evolution and determine the drivers of that dynamics using 1995 Landsat TM, 2013 Landsat OLI-TIRS imageries and field surveys. The supervised classification based on the ''Maximum likelihood'' algorithm was derived from ENVI 5.0 software. The transition matrix derived from Intersect function of ArcToolbox in ArcGIS 9.3 software was used to calculate the different conversion of land cover. The transition matrix was used to measure the intensities and speeds of land cover categories changes from 'PontiusMatrix22' 'and' 'Intensity Analysis02 programs. In addition, 200 household were surveyed from individual interviews and focus group on questionnaires and interview guides basis. The results show that the forest formations decreased from 48 % in 1995 to 20.4 % in 2013. The mosaics of fields and fallows have increased from 3 % to 24 %. The intensity change per land cover category shows that tree and shrub savannahs occurred the most significant change of 73 % of the study area with a 34 % of gain, 32 % of stability and 7 % of loss. In the order hand, the mosaics of fields and fallows, built up areas and dry dense forests occurred the biggest change. According to the perceptions of surveyed people, agriculture, logging and charcoal production are the main direct drivers of Trois Rivières forest reserve degradation.
2018 •
Forest in morocco is a very rich natural resource, but vulnerable. The DREFLCD-MA has taken the mission to study, preserve and direct this resource. In this document, we have responded to the specifications proposed by the DREFLCD-MA concerning the forest of Aghbalou-Larbi. We made the conceptualization of the methodology working on Hjirt forest, then we generalized it on all the forest of Aghbalou-Larbi. In a first place we mapped the stands of the Hjrt forest by trying two supervised classification methods: Spectral Angle Mapper and an approach based on RGB colored combination. We used the Sentinel 2 MSI image of the region. The RGB approach consisted of calculating two indices, NDWI for moisture and LAI-SAVI for adjacent soil. Beside these two indices, we added the second neo band calculated by principal component analysis ACP. The colored combination played the support for the supervised classification by the method of maximum likelihood. Then, we studied the spatiotemporal evolution of the forest during the past 37 years, using the 1990 stand map, the LandSat 5 images for the years 2000 and 2008, and the stand map that we establish for the year 2017. Then, we established a simulation model of forest evolution in the future by programming cellular automata based on rules of transition between species. After that, we tried to propose a plan of action based on those parameters: lithology, slope orientation and tree species. With these parameters we defined sectors where we proposed adequate intervention actions. Finally, we generalized this methodology throughout the Aghbalou-Larbi forest.
Objective: This study aims to characterize and to map vegetation cover in the mountainous region of Tonkpi in order to evaluate forest dynamics by remote sensing. Methodology and Results: This work relied on four satellite images of the scene 198-55 Landsat 4 TM 1990 from Landsat 7 ETM+ in 2000, Landsat 5 TM 2011 and Landsat 8 OLI-SHOTS 2015. Based on field data, classification was conducted using the maximum likelihood method in satellite images (OLI-SHOTS, ETM + and TM) in order to map vegetation from 1990 to 2015. These maps were superimposed to the Digital elevation model produced from an ASTER image in order to assess forest dynamics at altitude levels. The diachronic study of land use revealed a change in the landscape with a significant reduction of dense forest (-35.6%) and crop lands and fallow (-42.14%), and an increase of degraded forests (15.13%) and bare soil land and houses (10.46%). Moreover, high altitudes occupy a large proportion (37.7%) of the landscape (12,284 km 2), followed by medium altitudes (34.6%), and low altitudes (27.7%). Concerning bare soil and homes, there is a large increase of the area at low altitudes (88, 96%) while concerning crops and fallow, the area reduction was more pronounced at high altitudes (-53.64%). The medium altitudes have the highest rate of increase (51.14%) in degraded forests, and the highest decrease (-43.25%) in the dense forests. Conclusion and Application: The study shows that high altitudes occupy the largest proportion of the total area of the region and a change in the landscape due to human activities. Based on the results, we recommend a spatio-temporal monitoring of the net erosion on the mountains in order to maintain its agricultural potential and fight effectively against erosion.
Depuis plusieurs ann?es, les Technologies de l?Information et de la Communication (TIC) se sont diffus?es tr?s largement dans l?ensemble des secteurs d?activit? et des organisations, notamment avec la baisse des co?ts d??quipement et l?av?nement d?internet. Ce d?veloppement fulguraux ? donn? lieu ? plusieurs travaux de recherche et ?tudes, dont l?un des axes majeurs a port?, plus particuli?rement sur les questions de l?acceptation et de l?adoption des technologies d?information et de communication (TIC), et qui ont donn? naissance ? plusieurs mod?les th?oriques. Cette recherche, en prenant pour base ces mod?les et leurs th?ories sous-jacentes, s?inscrit dans ce sens et vise, ? ?tudier les d?terminants de l?acceptation des TIC par les dirigeants des structures d?h?bergement rurales de la r?gion de Souss Massa (Maroc). Le mod?leTAM3 (?tendu) a ?t? retenu comme cadre conceptuel de la recherche, qui a consist?e en une ?tude quantitative par questionnaire aupr?s de 40 dirigeants des entreprises ?tudi?es dont les donn?es ont ?t? analys?es en recourant aux m?thodes des ?quations structurelles. Les TIC sont devenues fondamentales pour la survie et la comp?titivit? des entreprises touristiques rurales et les r?sultats de notre recherche ont r?v?l? les d?terminants de leur acceptation par les dirigeants et les orientations pour les d?cideurs lors d??ventuelles interventions pour promouvoir l?acceptation et l?usage des TIC dans ce type d?entreprises. De m?me, nos r?sultats montre que le TAM3, tiens bien dans le contexte culturel marocain, jug? diff?rent de la culture d?origine du mod?le;
The cork oak forest of Benslimane province, which lies at its southern limit on a world scale, is characterized by the heterogeneity of its forest stands and the fragmentation of its forest area. These characteristics result from the interaction of various factors, including anthropogenic factors which are further aggravated by climate change. The heterogeneity of species that occupy the soil are represented by mixed pixels, which limits the reliability of conventional methods of classification. In the present study, we propose to apply a specific sub-pixel classification technique to spatial imagery from the Operational Land Imager (OLI) sensor of Landsat 8 to disaggregate the information and thus recover the spectral signatures specific to each \"pure\" component of the populations of the ecosystems studied.
Anticancer research
Whole Lung Irradiation in Patients with Osteosarcoma and Ewing Sarcoma2018 •
Revista Portuguesa de Estomatologia, Medicina Dentária e Cirurgia Maxilofacial
C-42. Fenótipo da Síndroma Trico-Dento-Ósseo – O papel da análise capilar no diagnóstico2013 •
REVISTA GEONORTE
“A VIDA NÃO É FÁCIL, A MINHA TAMBÉM NÃO FOI. MAS VALEU ATÉ AQUI” Entrevista com o professor Geraldo Alves de Souza2022 •
Journal of Medical Genetics
A novel X-linked recessive form of Mendelian susceptibility to mycobaterial disease2006 •
2020 •
Revista da Sociedade Brasileira de Medicina Tropical
Schistosomal glomerulonephritis: is it more prevalent in hepatosplenic patients when cor pulmonale is present?1989 •
Microwave and Optical Technology Letters
Microwave holographic 3-D rendering system using a reduced-size planar array antenna2001 •
Atatürk Üniversitesi Ziraat Fakültesi Dergisi
Peyzaj Karakter Analizi ve Değerlendirmesi: Pasinler-Köprüköy (Erzurum) İlçeleri Örneği2020 •
2013 •
2004 •
European Scientific Journal, ESJ
An Exploratory Study on Modern 3D Computerised Body Scanning System and Various Types of Pattern Making Software’s with Their Constructive Implementation in Apparel Industry2015 •
2017 •
Bipolar Disorders
Evidence for orbitofrontal pathology in bipolar disorder and major depression, but not in schizophrenia2005 •
Acta medica Indonesiana
COVID-19 Vaccines: Current Status and Implication for Use in Indonesia2020 •
Current Developments in Nutrition
Dietary Components and Metabolites Are Associated with Liver Fibrosis in People Living with HIV (PLWH) in the MASH cohort2020 •
1986 •
HAL (Le Centre pour la Communication Scientifique Directe)
Microwave-induced resistance oscillations as a classical memory effect2017 •
Revista de salud pública
Evidencia epidemiológica para una relación causal entre alcohol y violencia en Colombia2001 •
CHEST Journal
Higher Prognostic Value of Hypoxemia Than C-Reactive Protein in Bacteremic Pneumococcal Pneumonia2014 •
IEEE Radiation Effects Data Workshop
Heavy ion transient characterization of a hardened-by-design active pixel sensor arrayJournal of Eastern European and Central Asian Research (JEECAR)
Motivation factors of internal migration and agriculture in Azerbaijan