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IVES 9 IVES Conference Series 9 Spatial characterization of land use in the viticultural Maipo Valley (Chile), using aster image digital processing

Spatial characterization of land use in the viticultural Maipo Valley (Chile), using aster image digital processing

Abstract

[English version below]

L’entreprise viticole Concha y Toro S.A. gère environ 600 ha de vignes dans la Vallée du Maipo (A.O. Valle del Maipo). L’objectif est celui de caractériser spatialement ces vignobles et leur occupation du sol environnante. Le choix s’est porté vers la démarche de zonage viticole par l’analyse spatiale, utilisant des traitements d’images satellitaires afin d’avoir une vision synoptique de la zone à moindres coûts et délais. Un système d’informations géographiques (SIG) est construit à partir des données suivantes : cartes topographiques, géologique, fond cadastral numérique, images satellitaires. Un modèle numérique de terrain est par ailleurs construit à une résolution de 25 m à partir des cartes topographiques. Deux images Aster (résolution de 15 m) prises au mois d’octobre 2000 et janvier 2001 ont été choisies. Une cartographie de l’occupation du sol a été effectuée sur l’image satellitaire de janvier nous permettant par ailleurs d’actualiser les cartes topographiques datant de 1974, en raison notamment de l’expansion urbaine de la ville de Santiago en périphérie des vignes. Par ailleurs, l’étude diachronique mise en œuvre conduit à analyser les comportements spectraux des vignes et des sols et leur évolution spectrale entre les deux dates retenues.

Concha y Toro S.A. wine enterprise controls about 600 hectares of vineyards in the Maipo Valley (A.O. Valle del Maipo). Our purpose is to carry out a spatial characterization of vineyards and their surrounding land use, based on spatial analysis and using satellite image processing which enables to get a broad synoptic vision of the area at low cost. A geographic information system (GIS) is built with the following data: topographic maps, geological maps, digital cadastral database and satellite images. A digital elevation model (DEM) is made from the topographic maps at a 25 meters-resolution. Two high resolutions Aster images (15 meters) captured in October 2000 and January 2001 were chosen. Land use is spatially characterized using the January image. It enables us to update the land use cover extracted from the topographic maps and dating 1974, especially because of the urban sprawl of the city of Santiago amongst vines. More, the image diachronic study leads to analyze the spectral behavior of vine and soil and its evolution from January to February 2001.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

P. PARRA (1), E. VAUDOUR (1), M. C. GIRARD (1), E. HOLZAPFEL (2)

(1) Institut National Agronomique Paris-Grignon – UFR A GER/DM OS – Centre de Grignon BP0 1 – 78850 Thiverval Grignon – France
(2) Entreprise Viticole Concha y Toro – Gerencia Agricola – Avenida Nueva Tajamar 481, Torre Norte, oficina 306 – Santiago – Chile

Keywords

occupation du sol, sol, télédétection, vallée du Maipo, SIG, appellation d’origine
land use, soil, remote sensing, Maipo Valley, GIS, appellation of origin

Tags

IVES Conference Series | Terroir 2002

Citation

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