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1. Social capital, biocultural heritage and commoning for ethical and inclusive sustainability of peasant agriculture: three case studies in Argentina, Bolivia and Chile

Author

Lizbeth Núñez-Carrasco, Jorge Cladera, Pablo José Cruz, Nancy Egan, Gabriela Andrea Figlioli, Gaston Godoy-Garraza, Celeste Golsberg, Ximena Quiñones-Díáz, Luís Sáez-Tonacca, Manuela Vieira-Pak, and Thierry Winkel

Subjects
biocultural heritage, collective action, commons, ethical values, inclusive agriculture, participatory-action research, peasant farmers, quinoa, Environmental sciences, GE1-350
Abstract

Social issues and theoretical background: the sustainability of human societies depends on the intergenerational transmission of capital stocks, whether natural, social or economic. With ever more competition for economic resources, sustainability must increasingly focus on the mutual reinforcement of social and natural capital. This perspective is particularly relevant for peasant agriculture and producers, who are constantly at risk of social and economic exclusion, but whose social and natural capital remains important, though often underutilized, even by the peasants themselves. The concepts of commoning and social capital are useful for addressing these issues and activating biocultural heritage from an ethically inclusive sustainability perspective. Objective and methods: We seek to understand how peasants organize to collectively achieve goals of social and economic inclusion that could promote their sustainability and resilience in the face of economic constraints. Using field surveys and participatory action research, we analyzed the social, economic, and environmental factors that fostered the emergence and sustainability of producer organizations and their value chains. This was done in three peasant organizations in Argentina, Bolivia and Chile, whose common starting point is the valorization of traditional quinoa grain, but which differ greatly in terms of size, internal dynamics and organizational trajectories. Results: The successes and challenges of the social innovations implemented in the three cases studied provide lessons on how farmers can mobilize their social capital and leverage the resources of their cultural and natural capital to achieve ethically inclusive sustainability. While some lessons remain context-specific, others appear to be independent of the size and place of organizations, and several demonstrate the importance of socio-ethical interactions cultivated both within organizations and with consumers.

Published
2023
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2. Social adaptive responses to a harsh and unpredictable environment: insights from a pre-Hispanic andean society

Author

Pablo Cruz, Richard Joffre, Cyril Bernard, Nancy Egan, Bruno Roux, and Thierry Winkel

Subjects
andean highlands, archaeology, food storage, gini indices, settlement infrastructure, social inequality, sustainability, Biology (General), QH301-705.5, Ecology, QH540-549.5
Abstract

The scarcity or unpredictability of natural resources is a threat to cooperation within human societies. Exacerbated competition between individuals could affect social cohesion and collective action, generate conflicts over natural resources, and compromise their sustainable use. Yet, our in-depth archaeological study of the arid Andean highlands of Bolivia reveals the sustainable development of a complex agrarian society in a harsh environment marked, moreover, by a prolonged climatic degradation from the 13th to the 15th centuries. The 49 community settlements studied comprised independent family households that managed their own economic resources. A detailed study of the granary and housing structures of 549 of these households provided a strong quantitative data set for an analysis of Gini coefficients for grain storage capacity and housing area. This agro-pastoral society flourished with neither notable inequalities of wealth between villagers nor apparent long-lasting conflicts between villages. By sharing local knowledge, labor, and natural resources, this society succeeded both in limiting power and wealth concentration, and in sustainably producing food surpluses to be exchanged with neighboring populations. These results indicate a high degree of social cohesion and low levels of social and wealth inequality, similar to other well-established horticultural and agricultural societies around the world. We propose a conceptual model of low inequality in agrarian societies subject to extreme or unstable environments, where the sharing of knowledge, resources, and labor are the adaptive social responses to cope with the uncertainty in natural resources. The sustainability of the society is then guaranteed by a balance between collective action and family-based social organization.

Published
2022
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3. When the Past Lives in the Present. Agrarian Landscapes and Historical Social Dynamics in the Southern Andes (Quebrada de Humahuaca, Jujuy, Argentina)

Author

Pablo Cruz, Nancy Egan, Richard Joffre, Jorge L. Cladera, and Thierry Winkel

Subjects
agrarian landscape, Andes, landscape mapping, pre-Hispanic agriculture, Spanish colonial period, peasant dynamics, Agriculture
Abstract

This article examines the agrarian landscape in one part of the southern Andes (Quebrada of Humahuaca, Jujuy, Argentina). The region possesses extensive and well-preserved archaeological remains of agricultural systems, which stretch back to pre-Hispanic times. In this study, we employ an interdisciplinary approach in our analysis of the components that structure the agrarian landscape, especially those historical processes that intervened in its formation. The creation of a cartographic base, built from remote sensing and fieldwork data, allowed for the identification of four principal components of the landscape, each of which correspond to distinct phases or periods that mark the region’s history. Our study shows that, in contrast to what is observed in many other rural areas, the successive productive dynamics that developed in the area did not result in the destruction of previous productive structures. Rather, the agrarian landscape in the study area presents a multi-temporal agglutinating combination or composition, which transcends historical discontinuities in the productive matrix. This is owing to the partial reutilisation of previous structures in each period; however, religious and cultural factors play an important role. The agrarian landscape we studied is not only a passive result of human activity, but also a force influencing the productive and lifestyle decisions of the peasant populations that live there today. Our research amplifies the understanding of agrarian landscapes in the Andes and shows how past temporalities are articulated with the present through a dialectical process.

Published
2021
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4. Discontinuities in quinoa biodiversity in the dry Andes: An 18-century perspective based on allelic genotyping.

Author

Thierry Winkel, María Gabriela Aguirre, Carla Marcela Arizio, Carlos Alberto Aschero, María Del Pilar Babot, Laure Benoit, Concetta Burgarella, Sabrina Costa-Tártara, Marie-Pierre Dubois, Laurène Gay, Salomón Hocsman, Margaux Jullien, Sara María Luisa López-Campeny, María Marcela Manifesto, Miguel Navascués, Nurit Oliszewski, Elizabeth Pintar, Saliha Zenboudji, Héctor Daniel Bertero, and Richard Joffre

Subjects
Medicine, Science
Abstract

History and environment shape crop biodiversity, particularly in areas with vulnerable human communities and ecosystems. Tracing crop biodiversity over time helps understand how rural societies cope with anthropogenic or climatic changes. Exceptionally well preserved ancient DNA of quinoa (Chenopodium quinoa Willd.) from the cold and arid Andes of Argentina has allowed us to track changes and continuities in quinoa diversity over 18 centuries, by coupling genotyping of 157 ancient and modern seeds by 24 SSR markers with cluster and coalescence analyses. Cluster analyses revealed clear population patterns separating modern and ancient quinoas. Coalescence-based analyses revealed that genetic drift within a single population cannot explain genetic differentiation among ancient and modern quinoas. The hypothesis of a genetic bottleneck related to the Spanish Conquest also does not seem to apply at a local scale. Instead, the most likely scenario is the replacement of preexisting quinoa gene pools with new ones of lower genetic diversity. This process occurred at least twice in the last 18 centuries: first, between the 6th and 12th centuries-a time of agricultural intensification well before the Inka and Spanish conquests-and then between the 13th century and today-a period marked by farming marginalization in the late 19th century likely due to a severe multidecadal drought. While these processes of local gene pool replacement do not imply losses of genetic diversity at the metapopulation scale, they support the view that gene pool replacement linked to social and environmental changes can result from opposite agricultural trajectories.

Published
2018
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5. Variación fenotípica intra- e inter-poblaciones en siete poblaciones de quinua del Altiplano boliviano

Author

Carmen R. Del Castillo Gutiérrez and Thierry Winkel

Subjects
Análisis jerárquico, Bolivia, Chenopodium quinoa, población, variación fenotípica, Agriculture (General), S1-972, Plant culture, SB1-1110
Abstract

La quinua (Chenopodium quinoa Willd.) muestra una gran variación genética, tanto molecular como morfológica, cuya organización sigue poco conocida. Por medio de ANOVAs y dendrograma caracterizamos la estructura de la variación de marcadores morfofenológicos registrados desde la emergencia hasta la madurez fisiológica en siete poblaciones de quinuas cultivadas dos años en jardín común. Los resultados muestran que la varianza morfo-fenológica se concentra en niveles de población y familia, cuando los rasgos relacionados con la producción de biomasa muestran alta variación a nivel interindividual. Estos resultados tienen implicancias agroecológicas relacionadas con el origen geográfico de las poblaciones. La comparación de clasificaciones fenotípica y molecular sugiere que no hay erosión genética en las poblaciones de quinua muestreadas.

Published
2014

6. Pre-hispanic agricultural dynamics in the Quebrada of Morohuasi (Salta, Argentina)

Author

Pablo Cruz, Richard Joffre, Thierry Winkel, Bruno Roux, Christian Vitry, UE CISOR CONICET, Universidad Nacional de Jujuy, Jujuy, Argentina, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, 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)-Université de Montpellier (UM), Universidad Nacional de Salta, Subsecretaría de Patrimonio de la Provincia de Salta, Argentina, and This research was funded by MSH-SUD (Maison des Sciences de l’Homme SUD, France: Project PANARCHI 2017–2018, IRD/CNRS/UCM/UNJU), and ECOS-SUD (Scientific Cooperation Program Argentina/France: Project ARCHIPA 2020–2022).

Subjects
Archeology, southern Andes, Formative Period, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, [SDV.SA.AEP]Life Sciences [q-bio]/Agricultural sciences/Agriculture, economy and politics, [SHS.ANTHRO-SE]Humanities and Social Sciences/Social Anthropology and ethnology, History of agriculture, [SDE.ES]Environmental Sciences/Environmental and Society, [SHS]Humanities and Social Sciences, Inka, Land use changes, mitmaqkuna, pre-Hispanic agriculture, Agricultural landscapes
Abstract

Preprint de l'article publié le 06/12/2022 dans la revue "Ñawpa Pacha - Journal of the Institute of Andean Studies (Berkeley)", URL: https://doi.org/10.1080/00776297.2022.2136305; International audience; The Quebrada de Morohuasi (Salta Province, Argentina), located in a semi-arid high-altitude environment, is known to host vast pre-Hispanic cultivation areas. Recent archaeological studies carried out in the agricultural area of Morohuasi allow for a better definition and understanding of the social and productive dynamics that took place there. Field records and AMS dating indicate two main productive phases that were discontinuous in time. These show an initial phase during the Formative Period, between the 1st and 4th centuries CE, during which the agricultural substratum was formed, and a final phase during the first decades of the 15th century CE that was related to the establishment of an agricultural colony under the control of the Inkas. Although the same cultivation plots were utilized during both phases, the mode and relations of production were substantially different, particularly in the second phase with the participation of contingents of mitmaqkunas brought from other regions.; Ubicada en un ambiente semiárido de altura, la Quebrada de Morohuasi (Salta, Argentina) es conocida por albergar vastas áreas de cultivo prehispánicas. Los recientes estudios arqueológicos realizados en el área agrícola de Morohuasi permiten una mejor definición y comprensión de las dinámicas sociales y productivas que allí se dieron. Los registros de campo y las dataciones AMS realizadas indican dos fases productivas principales discontinuas en el tiempo. Una fase inicial durante el Período Formativo, entre los siglos I y IV CE, en la cual se conforma el sustrato agrícola, y una fase final durante las primeras décadas del siglo XV CE, relacionada con el establecimiento de una colonia agrícola bajo control de los inkas. Si durante ambas fases se cultivaron las mismas parcelas, el modo y las relaciones de producción fueron sustancialmente distintas, destacándose particularmente en la segunda la participación de contingentes de mitmaqkunas llevados desde otras regiones.

Published
2022

7. Ontogeny modifies the effects of water stress on stomatal control, leaf area duration and biomass partitioning of Pennisetum glaucum

Author

Thierry Winkel, Jean-François Renno, and W. Payne

Subjects
0106 biological sciences, 2. Zero hunger, Stomatal conductance, Physiology, 04 agricultural and veterinary sciences, Plant Science, 15. Life on land, Biology, 01 natural sciences, 6. Clean water, Anthesis, Agronomy, Botany, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Poaceae, Biomass partitioning, Leaf area index, Water-use efficiency, Water use, 010606 plant biology & botany, Transpiration
Abstract

• Experiments are presented that test the relative importance, during ontogeny, of stomatal control and leaf area expansion to optimum seasonal water use in pearl millet (Pennisetum glaucum). These parameters play a key role in the compromise between plant growth and water saving under unpredictable conditions of semiarid environments. • The response of growth and water use of crops to successive 15 d drought periods was measured under field conditions in Niger (West Africa). • From emergence to anthesis, biomass partitioning to stems and panicles depended strongly on leaf area development. Water use was linearly related to green leaf area duration in well watered plots, but was reduced proportionally more than green leaf area in drought-affected plots. The relations of crop growth rate and transpiration efficiency to leaf area depended on ontogenetic changes in biomass partitioning. • In P. glaucum, stomata play a dominant role in reducing crop water use under preanthesis drought, although this control becomes negligible after anthesis because of ontogenetic decline in the range of stomatal conductance. The rate of leaf senescence after anthesis is not drought-dependent.

Published
2021

8. Rooting plasticity in wild and cultivated Andean Chenopodium species under soil water deficit

Author

Richard Joffre, Ricardo Álvarez-Flores, Thierry Winkel, Anh Nguyen-Thi-Truc, Santiago Peredo-Parada, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
0106 biological sciences, root growth, [SDV.SA.AGRO]Life Sciences [q-bio]/Agricultural sciences/Agronomy, Taproot, Plant Science, 01 natural sciences, phenotypic plasticity, Chenopodium quinoa, C. hircinum, ComputingMilieux_MISCELLANEOUS, water deficit, plant domestication, 2. Zero hunger, Chenopodium pallidicaule, Biomass (ecology), Chenopodium quinoa Willd, root topology, biology, Ecotype, Chenopodium, Plant physiology, 04 agricultural and veterinary sciences, seed mass, Root architecture, Natural and human selection, C. pallidicaule, root shoot ratio, root plasticity, human and natural selection, Chenopodium hircinum, Soil Science, ecotype, root length, rhizotron, complex mixtures, plant adaptation, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, Agroecology, root system architecture, 15. Life on land, biology.organism_classification, root traits, Agronomy, Rhizotron, rooting depth, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, biomass allocation, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, 010606 plant biology & botany
Abstract

International audience; Background and Aims: Rooting plasticity is critical for plants exploiting patchy soil-water resources, but empirical evidence remains controversial due to complex root/soil interactions in natural and agricultural environments. We compared cultivated and wild Chenopodium populations from distinct agroecological background to assess their rooting plasticity when exposed to contrasting wet-dry soil profiles in a controlled environment.Methods: Four treatments of increasing dryness were applied during 6 weeks in plants of Chenopodium hircinum, Chenopodium pallidicaule and two ecotypes (wet- and dry-habitat) of Chenopodium quinoa grown in rhizotrons. Root system architecture and growth were sequentially mapped. At the end of the experiment, plant and root morphological traits and dry biomass were measured.Results: Contrary to the other two species, C. quinoa showed accelerated taproot growth in dry soil conditions. The dry-habitat C. quinoa ecotype showed consistently higher plant traits related to longer, coarser, and more numerous root segments which give it a faster taproot growth and sustained root branching at depth in dry soil.Conclusions: High rooting plasticity confers the advantage of fast root elongation and deep soil exploration under soil water deficit. Variation in intrinsic root traits and plastic responses among Chenopodium populations controls their root foraging capacity facing patchy soil-water resources.

Published
2018

9. Panarchy of an indigenous agroecosystem in the globalized market: The quinoa production in the Bolivian Altiplano

Author

Muriel Tichit, Jean-Joinville Vacher, Carmen Del Castillo, Marco Chevarria-Lazo, Anaïs Vassas-Toral, Jean-François Tourrand, François Léger, Manuela Vieira-Pak, Thierry Winkel, Juan-Peter Nina-Laura, Richard Joffre, Serge Rambal, Pierre Bommel, Geneviève Cortes, Pierre Gasselin, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Gestion des ressources renouvelables et environnement (Cirad-Es-UPR 47 GREEN), Département Environnements et Sociétés (Cirad-ES), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Institut National de la Recherche Agronomique (INRA), Acteurs, Ressources et Territoires dans le Développement (UMR ART-Dev), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Paul-Valéry - Montpellier 3 (UM3)-Université de Perpignan Via Domitia (UPVD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Universidad Mayor de San Andrés (UMSA), Innovation et Développement dans l'Agriculture et l'Alimentation (UMR Innovation), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Sciences pour l'Action et le Développement : Activités, Produits, Territoires (SADAPT), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Agrónomos y Veterinarios sin Fronteras (AVSF), Federal University of Lavras, Patrimoines locaux, Environnement et Globalisation (PALOC), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), Unité de recherche Paysannerie, Territoires, Environnement, Marchés et politiques Publiques (MONA), Facultad de Agronomia, Agronomes et Vétérinaires Sans Frontières, Departamento de Biologia, Universidade Federal de Lavras (UFLA), Patrimoines Locaux et Gouvernance (PALOC), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD), ANR-06-PADD-011-EQUECO, Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Gestion des ressources renouvelables et environnement (UPR GREEN), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Paul-Valéry - Montpellier 3 (UPVM)-Université de Perpignan Via Domitia (UPVD)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), 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)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Universidade Federal de Lavras = Federal University of Lavras (UFLA), Université Paul-Valéry - Montpellier 3 (UPVM)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE), 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 pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), 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 de Recherche pour le Développement (IRD)-Muséum national d'Histoire naturelle (MNHN), Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Université de Perpignan Via Domitia (UPVD)-Université Paul-Valéry - Montpellier 3 (UPVM), and AgroParisTech-Institut National de la Recherche Agronomique (INRA)

Subjects
010504 meteorology & atmospheric sciences, F08 - Systèmes et modes de culture, [SDV]Life Sciences [q-bio], Geography, Planning and Development, Agency (philosophy), 010501 environmental sciences, 01 natural sciences, 11. Sustainability, Economics, integrated assessment, Gouvernance, Economic geography, Structure agricole, Production alimentaire, media_common, 2. Zero hunger, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, Global and Planetary Change, Utilisation des terres, adaptive cycle, Ecology, E90 - Structure agraire, 1. No poverty, Social dynamics, Agroécosystème, Psychological resilience, Mondialisation, land use change, Exploitation agricole familiale, media_common.quotation_subject, Management, Monitoring, Policy and Law, Petite exploitation agricole, rural livelihood strategy, Globalization, Vulnerability assessment, Development economics, E50 - Sociologie rurale, transformative change, 0105 earth and related environmental sciences, Adaptive capacity, Moyens d'existence, E80 - Économie familiale et artisanale, 15. Life on land, Développement régional, approches participatives, Quinoa, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Commons, Panarchy
Abstract

International audience; Agricultural globalization is blamed for destructive impacts on small farms in developing countries. Yet, many local societies are proactive in the face of these changes and show high adaptive capacity. Investigating their transformations with an integrative perspective and enough hindsight may reveal some of the bases of their resilience and adaptive capacity. Using field data and the panarchy concept of resilience theory, we analyzed the territorial and social dynamics of quinoa growers' communities in southern Bolivia over the last four decades, a case study of regime shift in a poverty-stricken rural society which deliberately entered the global food market. Linking the dynamics of the household economy to the territorial and social subsystems over several decades, we gained insights into the interactions that shaped the rise of quinoa production in the region. We found that a vivid tradition of mobility allowing for pluriactivity on-and off-farm, combined with community self-governance, explains how local populations succeeded in articulating individual agency with collective control over their commons of land, seed resources, and social rules. Our vulnerability analysis points to landscape homogenization, social inequity, and increased dependence on external factors as potential sources of unsustainability. We conclude that, to cope with the changes of unprecedented magnitude they are facing, local producers should retain social cohesion and autonomous governance, without giving up on their heritage of mobility and economic redundancy. As regards theory, we identified cross-scale subsystem configurations critical for regime shifts, and confirm the value of panarchy in capturing complex socioecological dynamics.

Published
2016

10. The Sustainability of Quinoa Production in Southern Bolivia: from Misrepresentations to Questionable Solutions. Comments on Jacobsen (2011, J. Agron. Crop Sci. 197: 390-399)

Author

G. Rivière, Serge Rambal, J. Bourliaud, A. Vassas Toral, S. Geerts, Pierre Bommel, J. J. Vacher, François Léger, M. Chevarria Lazo, M. Vieira Pak, Muriel Tichit, Thierry Winkel, Jean-François Tourrand, Richard Joffre, Hector Daniel Bertero, Geneviève Cortes, Pierre Gasselin, and B. Martinez Avisa

Subjects
2. Zero hunger, Consumption (economics), Sociology of scientific knowledge, 010504 meteorology & atmospheric sciences, media_common.quotation_subject, Crop yield, Plant Science, 010501 environmental sciences, 15. Life on land, 01 natural sciences, Agricultural economics, Scarcity, Competition (economics), Agronomy, Soil retrogression and degradation, Sustainability, Economics, Production (economics), Agronomy and Crop Science, 0105 earth and related environmental sciences, media_common
Abstract

Reviewing the situation of quinoa production in southern Bolivia, Jacobsen (2011, J. Agron. Crop Sci. 197: 390) argues that the booming export market has a negative effect on the environment and on the home consumption of quinoa, thereby leading to an environmental disaster in the region. In view of the scarcity of scientific knowledge on the rapid social and environmental dynamics in the region, we consider that Jacobsen’s review misrepresents the situation of quinoa production in southern Bolivia. Specifically, we argue that (i) the data presented by Jacobsen (2011, J. Agron. Crop Sci. 197: 390) do not support any drop in quinoa crop yield supposed to reflect soil degradation and (ii) his demonstration regarding home consumption of quinoa is ill-founded from both a nutritional and a cultural point of view. We suggest that the diffusion of the arguments exposed by Jacobsen (2011, J. Agron. Crop Sci. 197: 390), because of their flaws, might have strong negative impacts on those concerned with sustainable food production and fair-trade with developing countries. We conclude that, rather than reinforced agro-technical controls on local farmers, the rising competition in the international quinoa market requires a shift towards an ethical economy and ethical research cooperation with quinoa producers.

Published
2012

11. Trends in quinoa yield over the southern Bolivian altiplano : lessons from climate and land-use projections

Author

Serge Rambal, Jean-Pierre Ratte, Florent Mouillot, Thierry Winkel, Murphy, K. (ed.), Matanguihan, J. (ed.), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Murphy, Kevin, Matanguihan, Janet, and ANR-06-PADD-0011,EQUECO,L'émergence de la Quinoa dans le commerce mondial : quelles conséquences sur la durabilité sociale et agricole dans l'Altiplano bolivien ?(2006)

Subjects
Prospective Modeling, Geography, Land use, Bolivian Altiplano, Agroforestry, General Circulation Model, Yield (finance), Forestry, Sustainability Assessment, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, climate model, Land use and climate changes
Abstract

International audience; The Southern Altiplano of Bolivia is the world-leader in quinoa export. In these arid highlands, quinoa yield is largely influenced by on-going changes affecting both climate drivers and land-use practices. We developed a simple “what-if” simulation model for anticipating such changes in quinoa yields over three time-slices: a recent past (1961-2000), a near future (2046-2065), and finally a remote one (2081-2100). Outputs from a global climate model (GCM) were used as drivers for projections of regional climate patterns and for providing risk information. For tackling further problems arising from our limited understanding of what the local-level impacts of climate change are likely to be in this arid mountain area, we decided to consider a grid level area centered on the salar of Uyuni, a region experiencing marked changes in climate and land-use for the past four decades. Local land-use change scenarios were derived from aerial photographs and data from high-resolution remote-sensing validated by ground truth observations on sample areas representative of the region. Climate change scenarios were linked to our yield model composed of a soil water balance model coupled with a simple crop growth component. The daily climate from GCM runs has been used for driving the soil water balance model and calculating the drought severity that the crop might undergo. At the field plot level, the yield index (defined as the the simulated yield relative to a fixed yield potential) depends on soil drought, mean air temperature that largely affects carbon assimilation through photosynthesis, and minimal temperature that impairs the yield during frost nights. At the landscape scale, a mosaic of three land units is considered: cerros (steep slopes), faldas (gentle slopes in piedmonts) and pampas (flat plains). We simulated 2-year crop cycles taking into account complementarities among these landscape units. In each land unit, growth efficiency parameters are affected by the decline in the biological potential of the land. These parameters parallel the rate of encroachment of the quinoa crop, the subsequent decline of pasture lands in the pampa area and the soil aeolian erosion caused by such intensification. Results show an on-going decrease in the occurrence of frost that will be followed by an increasing drought frequency in the forthcoming decades. Long-term increase in soil dryness associated with a decline in the biological potential of the land may largely impair the sustainability of this area. This type of analysis, although speculative, provides insights which can assist research and development organizations target options for sustainability in crop production.

Published
2015

12. El presunto desastre ambiental y social de la quinua real: desarmar los clichés para reforzar la ética

Author

Thierry Winkel, Pablo Cruz, Ricardo Alvarez-Flores, Daniel Bertero, Carmen del Castillo, Pierre Gasselin, Richard Joffre, Santiago Peredo Parada, Luis Sáez Tonacca, Anaïs Vassas Toral, Manuela Viera-Pako, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-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 pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut de Recherche pour le Développement (IRD), Consejo Nacional de Investigaciones Científicas y Técnicas, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), Instituto de Investigaciones Fisiologicas y Ecologicas Vinculadas a la Agricultura (IFEVA), Facultad de Agronomía [Buenos Aires], Universidad de Buenos Aires [Buenos Aires] (UBA)-Universidad de Buenos Aires [Buenos Aires] (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET), Facultad de Agronomia, Universidad Mayor de San Andrés (UMSA), Innovation et Développement dans l'Agriculture et l'Alimentation (UMR Innovation), 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)-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), Universidad de Santiago de Chile [Santiago] (USACH), Acteurs, Ressources et Territoires dans le Développement (UMR ART-Dev), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Paul-Valéry - Montpellier 3 (UPVM)-Université de Perpignan Via Domitia (UPVD)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), consultant, ANR-06-PADD-11-EQUECO, ECOS-Sud A11B03, PCCI-2012 12051, Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET)-Facultad de Agronomía [Buenos Aires], Universidad de Buenos Aires [Buenos Aires] (UBA)-Universidad de Buenos Aires [Buenos Aires] (UBA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut de Recherche pour le Développement (IRD [France-Sud]), and Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Université de Perpignan Via Domitia (UPVD)-Université Paul-Valéry - Montpellier 3 (UPVM)

Subjects
quinua, agricultural sustainability, preconception, [SDV]Life Sciences [q-bio], technoscience, ethics, [SHS]Humanities and Social Sciences
Abstract

International audience; The quinoa boom has provoked a lively debate about its social and ecological impacts in the southern Bolivian highlands, the world's leading export zone. An interdisciplinary analysis puts in perspective those changes seen in the last 40 years. While acknowledging the need for further support to local agrarian dynamics around quinoa production, we challenge affirmations about its unsustainability in southern Bolivia.; El auge de la quinua genera un vivo debate sobre sus impactos sociales y ecológicos en el altiplano sur de Bolivia, primer exportador mundial. Un análisis interdisciplinario permite poner en perspectiva los cambios ocurridos desde hace más de 40 años. Sin negar la necesidad de un apoyo a las dinámicas agrarias locales en torno a la quinua, se contestan aquellas afirmaciones que aseguran la insustentabilidad de la producción en el sur de Bolivia.

Published
2015

13. Sostenibilidad de la producción de quinua en el Altiplano Sur de Bolivia: un enfoque desde la panarquía

Author

Thierry Winkel, Pierre Pommel, Jean Bourliaud, Marco Allan Chevarria Lazo, Geneviève Cortes, Pierre Gasselin, Richard Joffre, Francois Leger, Serge Rambla, Gilles Rivière, Muriel Tichit, Jean-François Tourrand, Anaïs Vassas, Manuela Veira Pak, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), Unité de recherche Paysannerie, Territoires, Environnement, Marchés et politiques Publiques (MONA), Institut National de la Recherche Agronomique (INRA), Acteurs, Ressources et Territoires dans le Développement (UMR ART-Dev), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Paul-Valéry - Montpellier 3 (UM3)-Université de Perpignan Via Domitia (UPVD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Innovation et Développement dans l'Agriculture et l'Alimentation (UMR Innovation), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Sciences pour l'Action et le Développement : Activités, Produits, Territoires (SADAPT), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Mondes Américains (CERMA), Université Panthéon-Sorbonne (UP1)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS)-École des hautes études en sciences sociales (EHESS), Gestion des ressources renouvelables et environnement (Cirad-Es-UPR 47 GREEN), Département Environnements et Sociétés (Cirad-ES), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), ANR-06-PADD-011-EQUECO, Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Paul-Valéry - Montpellier 3 (UPVM)-Université de Perpignan Via Domitia (UPVD)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), 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)-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), Université Paris 1 Panthéon-Sorbonne (UP1)-École des hautes études en sciences sociales (EHESS)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS), Gestion des ressources renouvelables et environnement (UPR GREEN), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Université de Perpignan Via Domitia (UPVD)-Université Paul-Valéry - Montpellier 3 (UPVM), AgroParisTech-Institut National de la Recherche Agronomique (INRA), Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Université Panthéon-Sorbonne (UP1)-École des hautes études en sciences sociales (EHESS)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS)

Subjects
quinua, [SDV]Life Sciences [q-bio], sostenibilidad, bolivia
Abstract

Capitulo 10; Sostenibilidad de la producción de quinua en el Altiplano Sur de Bolivia: un enfoque desde la panarquía

Published
2015

14. Calling for a reappraisal of the impact of quinoa expansion on agricultural sustainability in the Andean highlands

Author

Luis Sáez Tonacca, Carmen Del Castillo, Pablo Cruz, Richard Joffre, Ricardo Álvarez-Flores, Thierry Winkel, Santiago Peredo Parada, Daniel Bertero, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), AGroécologie, Innovations, teRritoires (AGIR), Institut National de la Recherche Agronomique (INRA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Facultad de Agronomia, Universidad Mayor de San Andrés (UMSA), Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Université de Toulouse (UT)-Université de Toulouse (UT)

Subjects
debate, QUINOA, Public debate, PRODUCTION AGRICOLE, socioecological, ENVIRONNEMENT, Short-sighted, SOCIOECOLOGICAL, Political science, GESTION DE L'ENVIRONNEMENT, ETHIQUE, SOCIOECOLOGIE, COOPERATIVE AGRICOLE, ANDES, 098RURAL1, 076AGRO02, RESSOURCES SOCIOECOLOGIQUES, AGRICULTURE TRADITIONNELLE, biodiversity, 2. Zero hunger, SYSTEME D'EXPLOITATION AGRICOLE, Welfare economics, BIODIVERSITE, 1. No poverty, 15. Life on land, purl.org/becyt/ford/4.5 [https], AGROBIODIVERSITE, Agricultural sustainability, BOLIVIE, CIENCIAS AGRÍCOLAS, DEBATE, BIODIVERSITY, Otras Ciencias Agrícolas, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, General Agricultural and Biological Sciences, Agronomy and Crop Science, purl.org/becyt/ford/4 [https]
Abstract

International audience; The debate on the environmental and social sustentainability of quinoa in its area of major world production (southern highlands of Bolivia) revived with the acceptance by the United Nations of the Bolivian proposal to declare in 2013 as the Year of the Quinoa. Public debate focused on local impacts of quinoa expansion in the Southern highlands of Bolivia, denouncing several negative impacts of quinoa culture such as land degradation, socioeconomic disrupts and biodiversity loss. However, the global or at least the international implications of the expanding quinoa market were less debated and often in caricature, varying between culpability and ingenuity among consumers, while Andean producers were described as trapped by poverty or short sighted greed. If researchers are to make a relevant contribution to the debate on the impact of quinoa expansion on the social and environmental sustainability of the Andean agriculture, is it necessary to re-evaluate present knowledge and ignorance about local Andean production systems integrated with links at the global scales, taking into account local- global interactions. In the present paper are revisited some major ill- founded assertions commonly expressed in this debate and three lines of arguments are used to support the need for a more cautious and ethical approach to quinoa related issues.; Llamado a una revaluación del impacto de la expansión del cultivo de quinua sobre la sostenibilidad agrícola en el altiplano andino ABSTRACT The debate on the environmental and social sustentainability of quinoa in its area of major world production (southern highlands of Bolivia) revived with the acceptance by the United Nations of the Bolivian proposal to declare in 2013 as the Year of the Quinoa. Public debate focused on local impacts of quinoa expansion in the Southern highlands of Bolivia, denouncing several negative impacts of quinoa culture such as land degradation, socioeconomic disrupts and biodiversity loss. However, the global or at least the international implications of the expanding quinoa market were less debated and often in caricature , varying between culpability and ingenuity among consumers, while Andean producers were described as trapped by poverty or short sighted greed. If researchers are to make a relevant contribution to the debate on the impact of quinoa expansion on the social and environmental sustainability of the Andean agriculture, is it necessary to re-evaluate present knowledge and ignorance about local Andean production systems integrated with links at the global scales, taking into account local-global interactions. In the present paper are revisited some major ill-founded assertions commonly expressed in this debate and three lines of arguments are used to support the need for a more cautious and ethical approach to quinoa related issues. RESUMEN El debate sobre la sustentabilidad ambiental y social de la quínoa en el área de mayor producción en el mundo (tierras Andinas del sur de Bolivia) revivió con la aceptación por las Naciones Unidas de la propuesta de Bolivia de declarar el año 2013 como el Año Internacional de la Quínoa. El debate público se focalizó en los impactos locales de la expansión de la quínoa en las tierras Andinas del sur de Bolivia, denunciando diversos impactos negativos del cultivo de la quínoa tales como la degradación del suelo, conflictos socioeconómicos y pérdida de biodiversidad. Sin embargo, las implicancias internacionales o globales de la expansión del mercado de la quínoa fue menos debatido y a menudo cariturizado, fluctuando entre culpabilidad e ingenuidad entre consumidores en tanto que productores Andinos eran descritos como atrapados por la pobreza o una avaricia miope. Si los investigadores han de hacer un aporte relevante al debate del impacto de la expansión de la quínoa sobre la sustentabili-dad social y ambiental de la agricultura Andina, entonces es necesario reevaluar el conocimiento e ignorancia actual sobre los sistemas de producción andina en forma integrada con escalas globales, teniendo presente las interacciones locales-globales. En el presente estudio son revisadas algunas aseveraciones desafortunadas más importantes expresadas en este debate utilizando tras clases de argumentos para fundamentar la necesidad de un enfoque más cauto y ético en los problemas relacionados con la quínoa. Palabras clave: debate, biodiversidad, socioecológico.

Published
2014

15. Effect of the timing of water deficit on growth, phenology and yield of pearl millet (Pennisetum glaucum(L.) R. Br.) grown in Sahelian conditions

Author

Jean-François Renno, W. A. Payne, Thierry Winkel, Climat et fonctionnement des agro-écosystèmes, rôle de l'agrodiversité dans la stabilité de la production (CLIFA), Institut de Recherche pour le Développement (IRD), Caractérisation et valorisation de la diversité ichtyologique pour une aquaculture raisonnée (CAVIAR), International Crops Research Institute for the Semi-Arid Tropics [Niger] (ICRISAT), International Crops Research Institute for the Semi-Arid Tropics [Inde] (ICRISAT), and Consultative Group on International Agricultural Research [CGIAR] (CGIAR)-Consultative Group on International Agricultural Research [CGIAR] (CGIAR)

Subjects
0106 biological sciences, RENDEMENT, PENNISETUM GLAUCUM, Irrigation, Physiology, [SDV.SA.AGRO]Life Sciences [q-bio]/Agricultural sciences/Agronomy, PHYSIOLOGIE VEGETALE, TILLERS, Tiller (botany), Plant Science, Biology, 7. Clean energy, 01 natural sciences, Crop, PHENOLOGIE, DROUGHT RESISTANCE STRATEGY, PHENOLOGY, CROISSANCE, MAIN SHOOTS, Poaceae, Panicle, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, 2. Zero hunger, CYCLE VEGETATIF, ZONE SAHELIENNE, Phenology, SAHEL, 04 agricultural and veterinary sciences, 15. Life on land, biology.organism_classification, YIELD, DEFICIT HYDRIQUE, Agronomy, Shoot, PEARL MILLET, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Pennisetum, 010606 plant biology & botany
Abstract

Several studies conducted under high input conditions have indicated little susceptibility of pearl millet to water deficit untill early grain filling, because the losses in main shoot production were fully compensated by increased tiller fertility. The present study assessed the impact of water deficits at three development stages : prior to flowering (S30), at the beginning of flowering (S45), and at the end of flowering (S60) in pearl millet grown in experimental conditions similar to Sahelian farming conditions. It included a control irrigation treatment simulating the natural distribution of rainfall throughout the cropping season. Both biomass production and grain yield were severely reduced by S30 and S45, while S60 had no effect. In S30 and S45, the flowering of tillers was delayed or totally inhibited. In both of these treatments, the low number of productive tillers did not compensate for damage to panicle initiation and flowering of the main shoot. All treatments maintained green leaves on the main shoot during the grain filling period, and in S30 leaf growth recovered from mid-season drought. These results illustrate how pearl millet mostly escapes drought by matching its phenology to the mean rainfall distribution in the Sahel. In the case of mid-season drought, some late productive tillers and the maintenance of green leaf biomass of the main shoots limited, but did not overcome, the yield losses. This study stresses the importance of agro-ecological conditions in control treatments, particularly the water regime and crop density, when assessing crop drought resistance. (Résumé d'auteur)

Published
1997

16. Glossaire

Author

Thierry Winkel

Published
2013

21. Liminaires

Author

Thierry Winkel

Published
2013

23. Portfolio

Author

Thierry Winkel

Published
2013

36. Downscaling MODIS-derived maps using GIS boosted regression trees : the case of frost occurrence over the arid Andean highlands of Bolivia

Author

Serge Rambal, Thierry Winkel, Robin Pouteau, Fabien Goge, Jean-Pierre Ratte, Richard Joffre, Climat et fonctionnement des agro-écosystèmes, rôle de l'agrodiversité dans la stabilité de la production (CLIFA), Institut de Recherche pour le Développement (IRD), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), ANR-06-PADD-0011,EQUECO,L'émergence de la Quinoa dans le commerce mondial : quelles conséquences sur la durabilité sociale et agricole dans l'Altiplano bolivien ?(2006), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), ANR-06-PADD-011-EQUECO,ANR-06-PADD-011-EQUECO, Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
VARIATION SAISONNIERE, 010504 meteorology & atmospheric sciences, SYSTEME D'INFORMATION GEOGRAPHIQUE, [SDE.MCG]Environmental Sciences/Global Changes, AGROCLIMATOLOGIE, Soil Science, 01 natural sciences, Latitude, ALTITUDE, Altitude, GELEE, Computers in Earth Sciences, Digital elevation model, HAUTE ALTITUDE, 0105 earth and related environmental sciences, Remote sensing, TEMPERATURE DE SURFACE, Elevation, TELEDETECTION SPATIALE, ALTIPLANO, Geology, Lapse rate, 04 agricultural and veterinary sciences, 15. Life on land, TOPOGRAPHIE, 13. Climate action, Frost, VARIATION SPATIALE, 040103 agronomy & agriculture, PENTE, 0401 agriculture, forestry, and fisheries, Environmental science, Spatial variability, MODELE NUMERIQUE DE TERRAIN, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, ZONE DE MONTAGNE, Downscaling
Abstract

International audience; Frost risk assessment is of critical importance in tropical highlands like the Andes where human activities thrives at altitudes up to 4200 m, and night frost may occur all the year round. In these semi-arid and cold regions with sparse meteorological networks, remote sensing and topographic modeling are of potential interest for understanding how physiography influences the local climate regime. After integrating night land surface temperature from the MODIS satellite, and physiographic descriptors derived from a digital elevation model, we explored how regional and landscape-scale features influence frost occurrence in the southern altiplano of Bolivia. Based on the high correlation between night land surface temperature and minimum air temperature, frost occurrence in early-, middle- and late-summer periods were calculated from satellite observations and mapped at a 1-km resolution over a 45,000 km² area. Physiographic modeling of frost occurrence was then conducted comparing multiple regression (MR) and boosted regression trees (BRT). Physiographic predictors were latitude, elevation, distance from salt lakes, slope steepness, potential insolation, and topographic convergence. Insolation influence on night frost was tested assuming that ground surface warming in the daytime reduces frost occurrence in the next night. Depending on the time period and the calibration domain, BRT models explained 74% to 90% of frost occurrence variation, outperforming the MR method. Inverted BRT models allowed the downscaling of frost occurrence maps at 100-m resolution, illustrating local processes like cold air drainage. Minimum temperature lapse rates showed seasonal variation and mean values higher than those reported for temperate mountains. When applied at regional and subregional scales successively, BRT models revealed prominent effects of elevation, latitude and distance to salt lakes at large scales, whereas slope, topographic convergence and insolation gained influence at local scales. Our results highlight the role of daytime insolation on night frost occurrence at local scale, particularly in the early- and mid-summer periods when solar astronomic forcing is maximum. Seasonal variations and interactions in physiographic effects are also shown. Nested effects of physiographic factors across scales are discussed, as well as potential applications of physiographic modeling to downscale ecological processes in complex terrains. (résumé d'auteur)

Published
2011

37. Entre diálogo y fricción: enseñanza de un programa franco-boliviano de investigación y acción sobre sostenibilidad del cultivo de quinoa

Author

Thierry Winkel, Sarah Métais, Pierre Bommel, Jean Bourliaud, Marco Allan Chevarria Lazo, Geneviève Cortes, Pierre Gasselin, Richard Joffre, Francois Léger, Serge Rambal, Jean-Pierre Ratte, Gilles Rivière, Muriel Tichit, Jean-François Tourrand, Jean-Joinville Vacher, Anaïs Vassas Toral, Manuela Vieira Pak, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), Agronomes et Vétérinaires Sans Frontières, Gestion des ressources renouvelables et environnement (UPR GREEN), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Paysanneries, Territoires, Environnement, Marchés et politiques Publiques, Institut National de la Recherche Agronomique (INRA), UNOPS, United Nations Office for Project Services, Organisation des Nations Unies (ONU), PNUMA Programa de las Naciones Unidas para el Medio Ambiente, Acteurs, Ressources et Territoires dans le Développement (UMR ART-Dev), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Paul-Valéry - Montpellier 3 (UPVM)-Université de Perpignan Via Domitia (UPVD)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Innovation et Développement dans l'Agriculture et l'Agro-alimentaire (UMR Innovation), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-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), Sciences pour l'Action et le Développement : Activités, Produits, Territoires (SADAPT), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Centre de recherches sur les mondes américains (CERMA), Mondes Américains (CERMA), Université Paris 1 Panthéon-Sorbonne (UP1)-École des hautes études en sciences sociales (EHESS)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS)-Université Paris 1 Panthéon-Sorbonne (UP1)-École des hautes études en sciences sociales (EHESS)-Université Paris Nanterre (UPN)-Centre National de la Recherche Scientifique (CNRS), Universidad Técnica de Oruro (UTO). Oruro, BOL., Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Mondes Américains, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Centre National de la Recherche Scientifique (CNRS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Université de Perpignan Via Domitia (UPVD)-Université Paul-Valéry - Montpellier 3 (UPVM), AgroParisTech-Institut National de la Recherche Agronomique (INRA), and ProdInra, Migration

Subjects
[SDV] Life Sciences [q-bio], [SDV]Life Sciences [q-bio], formation, durabilité, quinoa, [SHS] Humanities and Social Sciences, recherche-action, bolivie, ComputingMilieux_MISCELLANEOUS, [SHS]Humanities and Social Sciences
Abstract

International audience

Published
2010

38. Assessing the protective effect of vertically heterogeneous canopies against radiative frost: The case of quinoa on the Andean Altiplano

Author

J.P. Nina Laura, Alain Rocheteau, J.P. Lhomme, C. Mamani Alcón, C. Del Castillo, Thierry Winkel, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Universidad Mayor de San Andrés (UMSA), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), 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)-Institut de Recherche pour le Développement (IRD [France-Sud])

Subjects
0106 biological sciences, Canopy, Limiting factor, Atmospheric Science, 010504 meteorology & atmospheric sciences, Field experiment, Biometeorology, Radiation view factor, 01 natural sciences, Leaf temperature, Botany, Canopy thermal stratification, Density of air, Cultivar, Chenopodium quinoa, Leaf area index, 0105 earth and related environmental sciences, 2. Zero hunger, Global and Planetary Change, Humidity, Forestry, 15. Life on land, Agronomy, Environmental science, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, [SDV.EE.BIO]Life Sciences [q-bio]/Ecology, environment/Bioclimatology, Agronomy and Crop Science, Night conditions, 010606 plant biology & botany
Abstract

International audience; Night radiative frost is a highly limiting factor for agriculture in Andean highlands. Nevertheless, a diversity of crop species was domesticated there, commonly showing high heterogeneity in plant growth at the field level. To examine a possible protective effect of crop canopy heterogeneity against nocturnal radiative frost, a dual approach combining a field experiment and a simplified energy balance model at the leaf level was used. Leaf and air temperatures were registered over an entire quinoa crop cycle in the Andean highlands of Bolivia, comparing two cultivars: Blanca de Yanamuyu, a traditional landrace with high plant height heterogeneity, and Surumi, a more homogeneous selected variety. In both cultivars, inverted air density profiles during calm and clear nights result in air temperature changes up to 4 °C over 1 m height, with minimum air temperature concentrated at the upper part of the canopy. In these conditions, leaf temperature gradients of up to 2.6 °C m-1 develop within the canopy of the traditional landrace, with minimum leaf temperature significantly higher (P < 0.001) in shaded plants of the landrace than in the selected cultivar. A dynamic model of leaf temperature based on canopy parameters and climatic records at screen level adequately simulates leaf temperature differences in the case of a vertically heterogeneous quinoa canopy. A sensitivity analysis of the model reveals that canopy height, leaf area index, and sky cloudiness are most important for the sheltering effect to develop, while air temperature and air humidity play a minor role under typical radiative frost conditions. As for wind velocity, its actual influence remains unclear due to experimental and modelling limitations at low wind speeds. The significance of these results is discussed in terms of the trade-off between stress adaptation and biomass productivity.This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright

Published
2009

39. Genetic structure of quinoa (Chenopodium quinoa Willd.) from the Bolivian altiplano as revealed by RAPD markers

Author

Jean-Philippe Bizoux, Carmen Del Castillo, Thierry Winkel, Grégory Mahy, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
0106 biological sciences, Germplasm, Bolivia, Plant Science, Biology, STRUCTURE DE POPULATION, 010603 evolutionary biology, 01 natural sciences, Chenopodium quinoa, [SDV.GEN.GPL]Life Sciences [q-bio]/Genetics/Plants genetics, PLANTE CULTIVEE, RAPD, Genetic variation, ETUDE COMPARATIVE, genetic structure, Genetics, Genetic erosion, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, 2. Zero hunger, Genetic diversity, Ecology, TECHNIQUE RAPD, genetic diversity, DIVERSITE GENETIQUE, 15. Life on land, STRUCTURE GENETIQUE, Pseudocereal, PLANTE SAUVAGE, VARIATION SPATIALE, Genetic structure, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Agronomy and Crop Science, 010606 plant biology & botany
Abstract

Quinoa (Chenopodium quinoa Willd.) is a pseudocereal originated from the Andes important for small farmers' food security as well as for commercial production. Recently, it has been claimed that in Bolivia genetic erosion could result from the marginalization of the crop in the north and from its commercial standardization in the south. The aim of this study was to quantify the hierarchical structure of the genetic variation present in eight quinoa field populations, consisting of cultivated and weedy individuals, representative of the altiplano and interandean valleys of Bolivia. Randomly amplified polymorphic DNA markers show that quinoa has a strong population structure and a high intra-population variation. An effect of geographical structure of the populations was highlighted, due to population isolation, not simply linked to distance but more probably to climatic and orographic barriers present in the studied zone. The population structure is also reinforced by the limited seed exchanges among farmers as revealed by field interviews. This population structure appears related to three major biogeographic zones: the northern and central altiplano, the interandean valley, and the southern Salar. Intrapopulation genetic diversity was higher than that expected for a mainly autogamous species, and higher than that reported in anterior studies based on germ.plasm collections. These results are commented in view of current knowledge on phylogeny and reproductive biology of the species, and their implications regarding genetic resources management are discussed.

Published
2006

40. Radiation use efficiency, chlorophyll fluorescence, and reflectance indices associated with ontogenic changes in water-limited Chenopodium quinoa leaves

Author

F. Thénot, Thierry Winkel, M. Méthy, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
0106 biological sciences, 010504 meteorology & atmospheric sciences, POTENTIEL HYDRIQUE, Physiology, Ontogeny, PHYSIOLOGIE VEGETALE, Plant Science, net photosynthetic rate, Photosynthesis, Photochemical Reflectance Index, 01 natural sciences, Chenopodium quinoa, leaf water potential, water stress, chemistry.chemical_compound, PLANTE CULTIVEE, PR!, Botany, CROISSANCE, ETUDE COMPARATIVE, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, FLUORESCENCE, Chlorophyll fluorescence, 0105 earth and related environmental sciences, STRESS HYDRIQUE, chlorophyll fluorescence, Chemistry, Plant physiology, quinoa, CHLOROPHYLLE, REFLECTANCE, Horticulture, Chlorophyll, Botánica, ETUDE EXPERIMENTALE, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, FEUILLE, PHOTOSYNTHESE, 010606 plant biology & botany
Abstract

International audience; Net photosynthetic rate, radiation use efficiency, chlorophyll (Chl) fluorescence, photochemical reflectance index (PRI), and leaf water potential were measured during a 25

Published
2002

41. The photochemical reflectance index (PRI) as a water stress index

Author

F. Thénot, Thierry Winkel, M. Méthy, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
010504 meteorology & atmospheric sciences, Water stress, 0211 other engineering and technologies, Water stress index, PHYSIOLOGIE VEGETALE, 02 engineering and technology, Photochemical Reflectance Index, Arbutus unedo L, 01 natural sciences, Chenopodium quinoa, PLANTE CULTIVEE, [SDV.SA.STA]Life Sciences [q-bio]/Agricultural sciences/Sciences and technics of agriculture, Botany, Reflectance measurement, ETUDE COMPARATIVE, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, ANALYSE STATISTIQUE, STRESS HYDRIQUE, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Arbutus unedo, Chenopodium quinoa Willd, biology, Chemistry, Wilting, Photochemical reflectance index PRI, biology.organism_classification, CHLOROPHYLLE, Reflectivity, REFLECTANCE, Horticulture, CLIMAT, General Earth and Planetary Sciences, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Chlorophyll fluorescence, FEUILLE, PHOTOSYNTHESE
Abstract

International audience; Measurements of leaf reflectance in two narrow wavelength bands centred around 530 and 570 nm were carried out during withering of two contrasting functional and structural types (annual vs. evergreen): Chenopodium quinoa (Willdenow) and Arbutus unedo (Linnaeus). The photochemical reflectance index PRI = (R530 - R570) / (R530 + R 570) was calculated. The results showed that PRI could be used as a reliable index for a non-destructive and low cost assessment of water stress. However, some limits with the PRI have to be emphasised, e.g. the wilting of leaves during the dry periods. If such limits are under control, PRI could be a way in remote sensing applications.

Published
2002
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42. Drought avoidance by asynchronous flowering in pearl millet stands cultivated on-farm and on-station in Niger

Author

Thierry Winkel, Anneke De Rouw, Sols, usages des terres, dégradation, réhabilitation (SOLUTIONS), Climat et fonctionnement des agro-écosystèmes, rôle de l'agrodiversité dans la stabilité de la production (CLIFA), and Institut de Recherche pour le Développement (IRD)

Subjects
0106 biological sciences, Irrigation, PENNISETUM GLAUCUM, Field experiment, Population, [SDV.SA.AGRO]Life Sciences [q-bio]/Agricultural sciences/Agronomy, PHYSIOLOGIE VEGETALE, Biology, ASYNCHRONY, 01 natural sciences, PRODUCTION VEGETALE, PHENOLOGIE, PHENOLOGY, Botany, Poaceae, education, Panicle, 2. Zero hunger, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, education.field_of_study, SECHERESSE, DROUGHT RESISTANCE, Phenology, Moisture stress, FLOWERING, 04 agricultural and veterinary sciences, 15. Life on land, ECOPHYSIOLOGIE, FLORAISON, NIGER, Agronomy, 040103 agronomy & agriculture, PEARL MILLET, 0401 agriculture, forestry, and fisheries, ECOPHYSIOLOGY, Soil fertility, Agronomy and Crop Science, RESISTANCE, 010606 plant biology & botany
Abstract

The effects of pre-flowering drought on millet were studied in two experiments, an on-station, dry-season trial under irrigation and an on-farm trial where drought was induced by natural rainfall regimes (one wet, two dry years). The on-station experimental conditions were adjusted to those of Sahel farms, particularly through low plant density, low soil fertility and an irrigation regime that simulated the natural rainfall pattern. The replanting (5–10%) of missing hills in the on-farm trial increased stand variance significantly, whereas small quantities of applied N reduced it. Grain yield and grain number were equally seriously affected by drought in both experiments; yields were 700–800 kg ha−1 in the control years compared with 200–300 kg ha−1 in drought years. Both experiments showed sub-populations of early-, intermediate- and late-flowering millet plants. Fertile tillers were concentrated in the group of early-flowering plants. Only this group when subjected to moisture stress could secure part of the grain production by delaying, to a maximum of 18 d, the development of fertile tillers beyond the period of stress. Later-flowering plants, mostly uniculm, would be either sterile or unaffected by drought, depending on the exact coincidence of panicle development and drought. Drought did not alter the number of fertile hills per stand, because earlier- or later-flowering plants in the same hill compensated for sterile plants. The period of flowering in a stand was stretched over 40–45 d independently of drought, and this occurred both in the on-station experiment comprising 19 plants per treatment and in the on-farm experiment comprising about 700 hills. Although stand variance was reduced by better crop management and resulted in more fertile hills, more panicles per hill, and taller hills of more uniform height, the spread in flowering period of the millet population tended to be unaffected. Stand variability therefore appeared to be of paramount importance in accounting for drought avoidance.

Published
1998

43. Experimental study of gene flow between wild and cultivated Pennisetum glaucum

Author

Jean-François Renno, F. Bonnefous, Thierry Winkel, Gilles Bezançon, Caractérisation et valorisation de la diversité ichtyologique pour une aquaculture raisonnée (CAVIAR), Climat et fonctionnement des agro-écosystèmes, rôle de l'agrodiversité dans la stabilité de la production (CLIFA), Institut de Recherche pour le Développement (IRD), ORSTOM - Niger (ORSTOM), ORSTOM, Diversité et génomes des plantes cultivées (UMR DGPC), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)

Subjects
0106 biological sciences, PENNISETUM GLAUCUM, Plant Science, engineering.material, Biology, 010603 evolutionary biology, 01 natural sciences, Gene flow, PLANTE CULTIVEE, PHENOLOGIE, PHENOLOGY, Botany, GENE FLOW, SEED GERMINATION, HYBRIDE, Domestication, Gene, TRANSFERT DE GENE, 2. Zero hunger, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, ZONE SAHELIENNE, Phenology, Morphological differentiation, WILD PEARL MILLET, SAHEL, food and beverages, FLOWERING, AMELIORATION DES PLANTES, biology.organism_classification, eye diseases, Agronomy, DOMESTICATION, Germination, PLANTE SAUVAGE, engineering, Pearl, Pennisetum, 010606 plant biology & botany
Abstract

Under natural conditions, wild and cultivated pearl millet, Pennisetum glaucum (L.) R.Br., exchanged genes for millenia and, nevertheless, maintain high morphological differentiation. Under experimental conditions in the Sahel, hybridization between wild and cultivated pearl millet was measured using isozymic markers and interpreted in relation to the phenology of the plants. Gene flows were asymmetric, engendering 8% of hybrids in the progeny of the wild phenotype, 45% in that of the cultivated phenotype, and 39% in that of the intermediate "shibra" phenotype; these last two phenotypes constitute the sample of cultivated pearl millet. The proportion of hybrids in the progeny of the wild sample was time dependent during the flowering phase of cultivated pearl millet. The proportion of hybrids produced by the cultivated pearl millet was not time dependent. In the seeds produced by the cultivated phenotype along its reproductive phase, the proportion of viable seeds was negatively correlated with the frequency of hybrids. Likewise, the speed of germination of seeds produced by the cultivated or the shibra phenotypes was negatively correlated with the frequency of the hybrids that they contained. The effects of balancing among genetic intermixing, isolation and reproduction barriers, and differential anthropic and natural selection pressures are discussed to better understand the evolution and the maintenance of the polymorphism of Pennisetum glaucum. Key words: pearl millet, wild pearl millet, Pennisetum glaucum, gene flow, domestication, hybrid.

Published
1997

44. Impact of late-season drought on water relations in a sparse canopy of millet (Pennisetum glaucum (L.) R. Br.)

Author

L. Cournac, Thierry Winkel, P. Louguet, and Frederic C. Do

Subjects
Canopy, Moisture, EVAPOTRANSPIRATION, CULTIVAR, fungi, CANOPEE, Soil Science, Sowing, food and beverages, PHYSIOLOGIE VEGETALE, Biology, medicine.disease, Canopy conductance, Agronomy, DEFICIT HYDRIQUE, Shoot, Soil water, medicine, Dehydration, Cultivar, Agronomy and Crop Science
Abstract

Although millet is known to be adapted to very dry conditions, little is known about its canopy water relations. The control of water loss and dehydration tolerance were studied during the grain filling for two cultivars presumed resistant and sensitive to moisture deficit at this stage. Two experiments were conducted in the dry hot season at Niamey, using crops based on the traditional system of hill sowing at low density : a preliminary trial with low leaf area (index of 0.7 at flowering) ; and a main trial with higher leaf area (index of 1.8) induced by tillering where parameters were recorded at a short time scale. The preliminary trial with small initial leaf area revealed a less apparent leaf water deficit according to leaf water potential and stomatal regulation but the main results were in agreement with those of the main trial. The cultivars were similar in their water relations. During drought, water losses declined quickly due essentially to a large decrease in the green leaf area through senescence. The potential effect of stomatal regulation was reduced by a natural decline of 50% after earing. The water deficit was relatively small and osmotic adjustement was absent in the upper leaves of eared shoots, which stayed green. These results reveal for millet, that rapid control of leaf area by senescence is the predominant mechanism at this stage, inducing long-term avoidance of dehydration of the upper leaves on eared shoots. The quick adjustment of canopy conductance to the reduction of soil water availability is an hypothesis advanced. (Résumé d'auteur)

Published
1996

45. Phenology and reproductive effort of cultivated and wild forms of Pennisetum glaucum under experimental conditions in the Sahel : implications for the maintenance of polymorphism in the species

Author

Jean-François Renno, Thierry Winkel, Caractérisation et valorisation de la diversité ichtyologique pour une aquaculture raisonnée (CAVIAR), Climat et fonctionnement des agro-écosystèmes, rôle de l'agrodiversité dans la stabilité de la production (CLIFA), and Institut de Recherche pour le Développement (IRD)

Subjects
0106 biological sciences, PENNISETUM GLAUCUM, SAHELIAN REGION, Plant Science, 010603 evolutionary biology, 01 natural sciences, Gene flow, ENDOGAMY, PLANTE CULTIVEE, PHENOLOGIE, PHENOLOGY, Botany, ETUDE COMPARATIVE, 2. Zero hunger, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, Cultivated plant taxonomy, biology, ZONE SAHELIENNE, Phenology, WILD PEARL MILLET, Reproductive isolation, AMELIORATION DES PLANTES, 15. Life on land, biology.organism_classification, REPRODUCTION, Agronomy, Sympatric speciation, PLANTE SAUVAGE, PEARL MILLET, REPRODUCTIVE EFFORT, Aboveground biomass, Pennisetum, 010606 plant biology & botany
Abstract

Dans les régions sahéliennes d'Afrique, les formes sauvage et cultivée du mil (#Pennisetum glaucum$ (L.) R. Br.) sont sympatriques et interfertiles, mais demeurent néanmoins distinctes depuis des millénaires. Les barrières à la reproduction ne suffisent pas à expliquer cette situation. Dans le but d'identifier d'autres mécanismes en jeu, la phénologie et l'effort reproductif des deux formes de mil ont été comparés en situation expérimentale au Sahel. La durée de la période de floraison de chaque type était beaucoup plus longue que la durée moyenne de floraison d'un individu. Quand les dernières plantes cultivées finissaient de fleurir, 65% des plantes sauvages étaient encore en train de fleurir et 30% commençaient à le faire. Ces dernières se trouvaient ainsi totalement isolées du flux de gènes de mil cultivé, dans une situation de reproduction endogamique. Les formes sauvage et cultivée du mil se différenciaient également par la répartition de leur investissement dans la biomasse aérienne, à l'exception du nombre de graines produites par plante. Comportement phénologique et effort à la reproduction contribuent au maintien de deux formes distinctes de mil. (Résumé d'auteur)

Published
1996

46. Spatial variation and temporal persistence of grapevine response to a soil texture gradient

Author

Thierry Bariac, Serge Rambal, Thierry Winkel, ORSTOM, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Laboratoire de Biogéochimie Isotopique, Université Pierre et Marie Curie - Paris 6 (UPMC), and Winkel, Thierry

Subjects
0106 biological sciences, Soil texture, Soil Science, Soil science, [SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study, 01 natural sciences, transect analysis, VARIATION TEMPORELLE, soil gradient, geostatistics, Transect, [SDV.SA.SDS] Life Sciences [q-bio]/Agricultural sciences/Soil study, ComputingMilieux_MISCELLANEOUS, plant biomass, 2. Zero hunger, Hydrology, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, Topsoil, Biomass (ecology), spatial scale, Water transport, BIOMASSE, soil texture, 04 agricultural and veterinary sciences, Vegetation, 15. Life on land, isotopic methods, spectral analysis, Spatial heterogeneity, [SDE.BE] Environmental Sciences/Biodiversity and Ecology, coherency analysis, VARIATION SPATIALE, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Environmental science, Spatial variability, Grapevine, spatial variability, RELATION SOL PLANTE, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, time persistence, TEXTURE DU SOL, 010606 plant biology & botany
Abstract

Studying the water transport in the soil-plant system requires information on the spatio-temporal variability of both subsystems and the ability to assess the impact of the soil heterogeneity and of the biological responses on the coupling between vegetation and its substrate. This study was conducted for 2 years in a vineyard in the Aude Valley, France, by measuring the particle size distribution of the topsoil, the instantaneous isotopic ratios ( 18 O 16 O , 2 H 1 H ) of leaf water, annual shoot biomass production, and interannual persistence of this biomass along a 360 m transect. The resultant spatial series were analysed for their correlations and converted to spectra. Changes in the isotopic ratios along the transect reflect the soil texture gradient, suggesting that the vines root deeper on the gravel layers than elsewhere. This could provide a mechanism for the partial decoupling between soil and vegetation, and thus explain (1) the strong temporal persistence of the vegetation pattern, (2) the low overall correlation between biomass production and soil texture. The spectra show that this correlation concentrates at specific scales which correspond to a minimum variability in the shoot biomass. In this case, therefore, soil texture plays only a minor role in determining the spatial heterogeneity of shoot biomass in grapevine.

Published
1995

47. Stomatal conductance of some grapevines growing in the field under a Mediterranean environment

Author

Thierry Winkel, Serge Rambal, and ORSTOM

Subjects
0106 biological sciences, Mediterranean climate, [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, Atmospheric Science, Stomatal conductance, Field (physics), Field experiment, PHYSIOLOGIE VEGETALE, Atmospheric sciences, 01 natural sciences, VIGNE, Botany, Cultivar, Transpiration, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, STOMATE, Global and Planetary Change, EVAPOTRANSPIRATION, Humidity, food and beverages, Forestry, 04 agricultural and veterinary sciences, MODELISATION, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Environmental science, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Agronomy and Crop Science, Water vapor, 010606 plant biology & botany
Abstract

International audience; A semi-empirical model of stomatal conductance was used to analyse porometer measurements on different grapevine cultivars under field conditions. Stomatal conductance was expressed as a function of quantum flux density, water vapour deficit, air temperature and leaf water potential. Where possible, the parameters describing the partial functions were estimated from field data and provide physiological insights into the transpiration process. They indicated differential stomatal sensitivity to air humidity in the various cultivars, a characteristic which could be related to their geographical origins.

Published
1990

48. Genetic structure of quinoa ( Chenopodium quinoa Willd.) from the Bolivian altiplano as revealed by RAPD markers.

Author

Carmen del Castillo, Thierry Winkel, Grégory Mahy, and Jean-Philippe Bizoux

Abstract

Abstract  Quinoa (Chenopodium quinoa Willd.) is a pseudocereal originated from the Andes important for small farmers’ food security as well as for commercial production. Recently, it has been claimed that in Bolivia genetic erosion could result from the marginalization of the crop in the north and from its commercial standardization in the south. The aim of this study was to quantify the hierarchical structure of the genetic variation present in eight quinoa field populations, consisting of cultivated and weedy individuals, representative of the altiplano and interandean valleys of Bolivia. Randomly amplified polymorphic DNA markers show that quinoa has a strong population structure and a high intra-population variation. An effect of geographical structure of the populations was highlighted, due to population isolation, not simply linked to distance but more probably to climatic and orographic barriers present in the studied zone. The population structure is also reinforced by the limited seed exchanges among farmers as revealed by field interviews. This population structure appears related to three major biogeographic zones: the northern and central altiplano, the interandean valley, and the southern Salar. Intrapopulation genetic diversity was higher than that expected for a mainly autogamous species, and higher than that reported in anterior studies based on germplasm collections. These results are commented in view of current knowledge on phylogeny and reproductive biology of the species, and their implications regarding genetic resources management are discussed. [ABSTRACT FROM AUTHOR]

Published
2007
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49. Influence of Water Stress on Grapevines Growing in the Field: From Leaf to Whole-Plant Response

Author

Serge Rambal, Thierry Winkel, and ORSTOM

Subjects
0106 biological sciences, Ecophysiology, Stomatal conductance, VARIATION SAISONNIERE, leaf area, POTENTIEL HYDRIQUE, ecophysiology, Field experiment, BILAN HYDRIQUE, Vapour pressure of water, [SDV.SA.AGRO]Life Sciences [q-bio]/Agricultural sciences/Agronomy, PHYSIOLOGIE VEGETALE, Plant Science, Biology, 01 natural sciences, leaf water potential, plant hydraulic conductance, water stress, Hydraulic conductivity, Botany, ETUDE COMPARATIVE, Cultivar, plant biomass, STRESS HYDRIQUE, Transpiration, CULTIVAR, fungi, time scale, food and beverages, 04 agricultural and veterinary sciences, 15. Life on land, grapevine, Horticulture, stomatal conductance, Soil water, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, hydraulic architecture, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Agronomy and Crop Science, VARIATION JOURNALIERE, 010606 plant biology & botany
Abstract

International audience; A comparative study of soil-plant water relations was conducted on three grapevine cultivars (Vitis vinifera L. cvv. carignane, merlot, shiraz) to investigate their adjustment to short-term and long-term water stress under field conditions. Adjustment was a function of the relative stability of the internal plant water status on diurnal and seasonal scales. On a diurnal scale, stomatal closure in response to water vapour pressure directly contributed to this stability. Indirect evidence suggested an influence of the soil water status on the diurnal stomatal activity. On a seasonal scale, sufficient leaf hydration required high whole-plant hydraulic conductance. This was achieved by either daily stomatal regulation or limitation of leaf area. Physiological adjustment to water stress through stomatal control was well developed in cv. carignane, which originated in a Mediterranean environment. However, cv. shiraz, which was of mesic origin, apparently adjusted to water stress by reducing leaf area. Our study demonstrates the utility of integrating data on stomatal conductance, leaf water potential and whole-plant hydraulic conductance to interpret whole plant adaptation to water stress, and elucidates two mechanisms by which genotypes differentially acclimate to water stress.

Published
1993

50. Testing an area-weighted model for albedo or surface temperature of mixed pixels in Mediterranean woodlands

Author

Thierry Winkel, Serge Rambal, B. Lacaze, and ORSTOM

Subjects
Mediterranean climate, 010504 meteorology & atmospheric sciences, Correlation coefficient, 0211 other engineering and technologies, land surface temperature, 02 engineering and technology, 01 natural sciences, Multispectral pattern recognition, remote sensing, ALBEDO, ETUDE COMPARATIVE, geostatistics, Linear combination, spatial variability : albedo, Image resolution, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, TEMPERATURE DE SURFACE, Pixel, FORMATION VEGETALE, TELEDETECTION SPATIALE, Vegetation, 15. Life on land, Albedo, RESULTAT ANALYTIQUE, [SDE]Environmental Sciences, General Earth and Planetary Sciences, Environmental science, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience; We have tested the following assumption for a spatially complex area of natural vegetation in Southern France. The spectral response of a mixed pixel is a linear combination of the individual responses of its components. The test has been done with HCMM data: each pixel (500m spatial resolution) has been characterized by its components defined as physiognomical vegetation units. Results from the analysis of multitemporal HCMM data indicate that the assumption is verified for albedos and surface temperatures.

Published
1989

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