POTENTIAL GRAPE - GROWING SITES IN THE TROPICS: EXPLORATION AND ZONING USING A GIS MULTI-CRITERIA EVALUATION APPROACH

摘要

Traditional viticultural regions have been defined worldwide as those grape-growing regions located between the 10°C and 20°C isotherms in both hemispheres, mainly because of the climatic friendly conditions due to their geographical position on the globe. Other important factors are: the region's soil, geology and topography, as well as the grapevine varieties that grow well and produce quality grapes. Together with these factors, certain wine traditions practiced for decades contribute to creating the wine terroirs of the region. Site selection for potential vineyards worldwide is becoming important in the context of growing international wine market and the need to cope with the wine-grapes demand. This would lead to the expansion of existing vineyards and the exploration of potential viticultural zones, particularly in the emerging grape growing countries and/or in other areas in the tropics beyond the geographical limits defined by the above-mentioned isotherms. Indicators and criteria for selecting potential sites in the temperate region have mainly been defined based on temperature and climatic variations along the latitudinal axis are quite remarkable as compared to the seasonal and climatic changes along the same axis in the tropics. This study is concerned with the development of a new set of suitability indicators that will involve climatic conditions and plant-soil-water relationship. The GIS multi-criteria methodology proposed in this paper describes the definition and evaluation of the selected indicators and criteria for exploring highly suitable potential grape-growing sites, viticultural zones and future wine terroirs in the tropics. Indicators are evaluated using high resolution remote sensing and climatic model data. Individual suitability maps developed per indicator are aggregated together later on to yield an overall suitability map for viticultural potential that can be used for zoning and vineyards exploration in the tropics.