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Artigo Revisado por pares

Christine Rasoazanamparany, Elisabeth Widom, David Kuentz, Tsilavo Raharimahefa, K.M. Rakotondravelo, A.M.F. Rakotondrazafy,

... for Quaternary basaltic lavas and tephra from the Itasy volcanic field, in order to assess the origin ... between ∼31 and 104 ka. Mafic magmas from Itasy exhibit significant geochemical heterogeneity, and they are chemically ... Ankaratra volcanic complex. Trace element signatures of the Itasy volcanic field are very similar to those of ... with highly radiogenic Os isotopic signatures in many Itasy samples, could be attributed to assimilation of the ... Os, the elemental and isotopic characteristics of the Itasy magmas are inconsistent with significant crustal assimilation, and ...

Tópico(s): High-pressure geophysics and materials

2021 - Elsevier BV | Geochimica et Cosmochimica Acta

Artigo Acesso aberto Revisado por pares

Onjaherilanto Rakotovao Razanakoto, Sitrakiniaina Raharimalala, Eddy J Randriamihary Fetra Sarobidy, Jean-Chrysostome Rakotondravelo, Patrice Autfray, Hanitriniaina Mamy Razafimahatratra,

... of sub-Saharan African country like Madagascar. The Itasy Region has developed there vegetable crops for marketing purpose. Part of the Itasy agricultural practices may be assimilated to conventional ones, ... has deliberately chosen the peri-urban area of Itasy to perform a survey to 171 households that ... inside two Communes of Arivonimamo, a District of Itasy. This paper aims to assess how far agroecological ... term. This study concludes that market-gardening in Itasy mobilizes reduced chemical input at farm scale. Agroecology ...

Tópico(s): Agricultural Innovations and Practices

2020 - SAGE Publishing | Outlook on Agriculture

Artigo Acesso aberto Revisado por pares

Tsiry Andrianampiarivo,

... detailed data from 508 households in the 2008 Itasy Observatory. We stratify them using four distinguishing socio- ... that reflect the agro-economic diversity of the Itasy region: a vulnerable group of agriculturally diversified households ...

Tópico(s): Migration, Ethnicity, and Economy

2016 - Routledge | Review of Social Economy

Artigo Revisado por pares

Nathalie Charbonnel, R. Rasatavonjizay, Elizabeth Sellin, Philippe Brémond, Philippe Jarne,

... mansoni in Africa, in two areas of Madagascar (Itasy and Antananarivo). We confirmed that B. pfeifferi is ... the spatio‐temporal mating system variations observed in Itasy area. However genetic factors including inbreeding depression‐the ... the mating system in both populations sampled in Itasy and lead to different levels of evolutionary stable ...

Tópico(s): Evolution and Genetic Dynamics

2004 - Wiley | Oikos

Artigo Revisado por pares

Leone Melluso, Robert D. Tucker, Ciro Cucciniello, Anton P. le Roex, Vincenzo Morra, Alberto Zanetti, R.L. Rakotoson,

The Itasy is a Pleistocene-Holocene volcanic field in central Madagascar, located to the west of the Ankaratra volcanic ...

Tópico(s): earthquake and tectonic studies

2018 - Elsevier BV | Lithos

Artigo Revisado por pares

Narindra H. Rakotovao, Tantely Razafimbelo, Stéphan Rakotosamimanana, Zafyson H. Randrianasolo, Josoa R. Randriamalala, Alain Albrecht,

... agroecological practices were planned for farmers in the Itasy region, Central Highlands of Madagascar. The project consisted ... to assess the CFP of farms in the Itasy region Central Madagascar, (ii) to assess the impact ...

Tópico(s): Environmental Impact and Sustainability

2016 - Elsevier BV | Journal of Cleaner Production

Artigo Acesso aberto

J. Daget, Jacques Moreau,

... une population de Poissons hybrides dans le lac Itasy, à Madagascar, en 1963-64.Ces poissons, appelés ... hybrid fishes appeared in 1963-64 in the Itasy lake (Madagascar).These fishes called Tilapia trois-quarts ... of this phenomenon are discussed. I. Le lac Itasy et sox peuplement de PoissonsLe lac itasy (35 km 2 ) a déjà été décrit plusieurs ...

Tópico(s): Aquatic Ecosystems and Biodiversity

1981 - Muséum national d'histoire naturelle | Bulletin du Muséum national d histoire naturelle

Artigo Revisado por pares

Narindra H. Rakotovao, Tiphaine Chevallier, Lydie Chapuis‐Lardy, Sylvain Deffontaines, Syndhia Mathé, Mamonjiniaina Andriamirajo Ramarofidy, Tsifera Henintsoa Rakotoniamonjy, Adrien Lepage, Cargele Masso, Alain Albrecht, Tantely Maminiana Razafimbelo,

Rural development projects to develop sustainable agriculture need to be assessed before engaging smallholder farmers at large scale. Data on agricultural systems to produce food, provide income for smallholders and reduce greenhouse-gas (GHG) emissions are scarce in Sub-Saharan Africa countries. Here, we assessed the potential of agroecological practices (AP) on economic benefits to farmers, GHG balance derived from agricultural activities, and efficiency of economic investments to mitigate GHG. ...

Tópico(s): Agriculture, Land Use, Rural Development

2020 - Elsevier BV | Journal of Cleaner Production

Artigo Acesso aberto Revisado por pares

Tsilavo Raharimahefa,

... Ankarana caves, hot springs and volcanic lakes of Itasy, all of which should be conserved and protected ...

Tópico(s): Paleontology and Evolutionary Biology

2013 - African Journals OnLine | Madagascar Conservation & Development

Artigo Revisado por pares

Jean Rasoarahona, Gilles Barnathan, Jean‐Pierre Bianchini, Émile M. Gaydou,

... of mean weight 100–250 g collected in Itasy lake of Madagascar highlands during three seasons, were ...

Tópico(s): Aquaculture disease management and microbiota

2004 - Elsevier BV | Food Chemistry

Artigo Revisado por pares

Jean Rasoarahona, Gilles Barnathan, Jean‐Pierre Bianchini, Émile M. Gaydou,

... the reserve pond of Sisaony (SIS series) and Itasy Lake (ITA series) of the Madagascar highlands. Total ...

Tópico(s): Aquaculture disease management and microbiota

2004 - American Chemical Society | Journal of Agricultural and Food Chemistry

Artigo Revisado por pares

Leone Melluso, Vincenzo Morra,

... formation of the large alkaline volcanic fields of Itasy and Ankaratra in central Madagascar.

Tópico(s): Geochemistry and Geologic Mapping

2000 - Elsevier BV | Journal of Volcanology and Geothermal Research

Artigo Revisado por pares

Jean‐Pierre Fourno, J. Roussel,

... of Cretaceous volcanism emphasized by the Ankaratra and Itasy massifs. Final separation nevertheless occurred further east, at ...

Tópico(s): Geological formations and processes

1994 - Wiley | Terra Nova

Artigo Revisado por pares

M. Vuillaume-Randriamanantena,

... the subfossil site of Ampasambazimba in central Madagascar (Itasy basin), is poorly understood not merely because few ...

Tópico(s): Animal Behavior and Reproduction

1988 - Elsevier BV | Journal of Human Evolution

Artigo Revisado por pares

Arno J. Mayer,

... to a Malagasy rural area: the case of Itasy, Review of Social Economy 75, no.11 (May ...

Tópico(s): Social Policy and Reform Studies

1975 - University of Chicago Press | The Journal of Modern History

Artigo Acesso aberto Revisado por pares

R. L. Baron,

... in Mandricirano, on the western side of Lake Itasy, and in the neighbourhood of Betafo in Vakin ... of Madagascar.1 On the west side of Itasy the volcanic cones exist in great numbers, and ...

Tópico(s): Plant Diversity and Evolution

1886 - Nature Portfolio | Nature

Artigo Acesso aberto Revisado por pares

M. Rajaobelison, Jasmin Raymond, Michel Malo, Chrystel Dezayes,

... 2) fossil magmatic liquid-dominated moderate-temperature (Ambanja, Itasy and Antsirabe areas), and (3) sedimentary liquid-dominated ...

Tópico(s): Geothermal Energy Systems and Applications

2020 - Springer Science+Business Media | Geothermal Energy

Artigo

Andrianainarivelo Mahandrimanana, Ranaivoson Joseph,

The aim of this work is to highlight the physicochemical properties of three various types of clay soils respectively collected at Bevalala (sample 1), Arivonimamo (samp le 2) and Antsirabe (sample 3). The analyses obtained by x-ray fluorescence showed the variation of the co mposition of the major elements in each samp le in part icular the rates of SiO 2 (47.6%, 41.2%, 52.5%), of A l 2 O 3 (16%, 23%, 25%), of MgO (0.52%, 0.39%, 1.9%) and of Fe 2 O 3 (8.3%, 4.7%, 6.4%) at 500°C. . The study of the plasticity ...

Tópico(s): Soil and Unsaturated Flow

2013 - | International Journal of Materials and Chemistry

Artigo Revisado por pares

René Battistini,

Tópico(s): Geotourism and Geoheritage Conservation

1962 - Armand Colin | Annales de Géographie

Artigo

J C F Randrianiaina Jerry, I Rakotonirina Rija, R Ratiarimanana Jean, Lahatra Razafindramisa Fils,

... GIS) to monitor surface water temperature in Lake Itasy. Lake Itasy is among of the continental lakes of Madagascar. Sited within the volcanic field of the Itasy. Its surface is about 35 km². We derived ... C on June 2018. It indicated that Lake Itasy water respects the Malagasy norm in point of ...

Tópico(s): Aquatic Ecosystems and Biodiversity

2018 - | Resources and Environment

Artigo Revisado por pares

John S. Sparks,

Ptychochromoides itasy, new species, is described from material collected from Lake Itasy and environs in the central highlands of Madagascar. ... shorter snout. Although reportedly once abundant in Lake Itasy, specimens referable to the new species have not ...

Tópico(s): Fish Ecology and Management Studies

2004 - Q15088586 | Zootaxa

Artigo Acesso aberto

Masashi Konoshima, Tetsuji Tonda, Ken‐ichi Kamo, Bam H.N. Razafindrabe,

... surrounding land uses on the extents of Lake Itasy, in Madagascar. In order to demonstrate our approach, ...

Tópico(s): Conservation, Biodiversity, and Resource Management

2021 - | FORMATH

Artigo Acesso aberto

G. F. Scott Elliot,

... first part of my journey was to Lake Itasy, which is about two days' journey west of ... confined to it. The whole district near Lake Itasy is volcanic ; the country is studded with small ... of the land through volcanic action. From Lake Itasy I went to Mr. MacMahon's station at ...

Tópico(s): African Botany and Ecology Studies

1891 - | Proceedings of the Royal Geographical Society and Monthly Record of Geography

Artigo Revisado por pares

John S. Sparks, Paul V. Loiselle, Zachary H. Baldwin,

Ptychochromoides itasy Sparks, 2004, known locally in Madagascar as the trondro mainty or marakely à bosse, a robustjet black ... be extinct. Recently, a relict population of P. itasy was discovered in a tributary of the Tsiribihina ... Ptychochromoides and to resolve the placement of P. itasy within the genus.

Tópico(s): Fish Ecology and Management Studies

2012 - Q15088586 | Zootaxa

Artigo Revisado por pares

Tsiry Andrianampiarivo,

... milieux ruraux et transformation structurelle à Madagascar, en Itasy. La structure de classes de moyens d’existence ... structure profondément hétérogène de l’espace social en Itasy et la diversité des processus de transformation rurale ...

Tópico(s): French Urban and Social Studies

2018 - | Mondes en développement

Artigo Revisado por pares

Tsiry Andrianampiarivo, Claire Gondard‐Delcroix,

... explored Malagasy context. Using data from the 2008 Itasy Observatory survey, we conducted a cluster analysis to ...

Tópico(s): Innovation and Socioeconomic Development

2022 - Taylor & Francis | Oxford Development Studies

Artigo

Rija I. Rakotonirina, Jerry J. C. F. Randrianiaina, F. Lahatra Razafindramisa,

... is to assess the current state of Lake Itasy, the third largest lake in Madagascar. Temperature, pH, ...

Tópico(s): Aquatic Ecosystems and Biodiversity

2020 - | Resources and Environment

Artigo Revisado por pares

Gérard Mottet,

... est le massif le plus complexe de l'Itasy, du point de vue pétrographique, comme du point ...

Tópico(s): Geological and Geophysical Studies Worldwide

1975 - Association de Geographes Francais | Bulletin de l Association de géographes français