Delineating vineyard management zones: Intrafield spatial variability of soil properties of carbonate vineyard soils

Abstract

Grapevine (Vitis vinifera L.) is a traditional crop cultivated in Navarre (NE Spain). However, in some areas, it is grown without harnessing land suitability for its cultivation. This research was conducted to approach the pedological recognition of viticulture zoning (on the farm scale) in a traditional and distinct viticultural region: Olite (Navarre). As grape yield and grape quality in a given field are generally variable and do not coincide one way or another, 13 soil profiles were selected for pedological description and analysis in an attempt to recognise the importance of soil properties. For that purpose, 45 soil samples (corresponding to the different pedogenetic horizons of the 13 soil profiles) were collected to improve zonal vineyard estimations. The most notable characteristics of the studied soils were the presence of petrocalcic horizons, high stone fragments content, mainly loamy textures, high pH (between 8.24 and 9.24), high carbonate (between 19.1% and 90.0%), and active limestone contents (between 5.7% and 26.1%), and relatively low organic matter contents (<3.34%). Appreciable soil properties variability was detected from the results of this study and, therefore, variability in production and grape composition was expected. These results emphasise the spatial variability of the study area soils in a way that allows for the delineation of homogeneous viticultural zones. The results also provide the necessary information not only for viticultural zoning in the Navarre wine-growing region, but also in wine-growing regions with a Mediterranean continental climate. Hence, our findings will allow future viticultural management zones to be developed and specific practices to be implemented.