Terroir Suitability Zoning for the Six Prevailing Wine Grape Varieties in Ningxia Hui Autonomous Region (with a Focus on the Helan Mountain East) of China

Terroir plays an important role in wine grape production and good wine making.Among all the aspects of terroir in a given region, climate, soil and variety are the most important ones.The goal of this study was to evaluate these three aspects of terroir in Ningxia Hui Autonomous Region of China, with a focus on the Helan Mountain East.Based on historical weather data during the period 1981 to 2016 from 22 meteorological stations in the research area, the climatic indices were derived, with which the growable zone for wine grape cultivation in the research area was identified.By synthesizing the climatic indices and soil type data, stepwise and optimization methods were used to divide the growable zone into optimal, suitable, near-suitable and unsuitable zones for the six prevailing wine grape varieties.In the analysis, the six prevailing wine grape varieties include two white wine grape varieties of "Chardonnay" and "Riesling" and four red wine grape varieties of "Cabernet Sauvignon", "Merlot", "Pinot Noir" and "Grenache Noir".With the Geographic Information System (ArcGIS) software, the geographical distributions of these terroir suitability zonings were mapped in the research area according to a small grid simulation model.The results showed that the growable zone for wine grapes was mainly focused in most of the northern and central parts of Ningxia Hui Autonomous Region.This particular zone was suitable for the typical red wine varieties like late-maturing "Grenache Noir", medium-to-late maturing "Cabernet Sauvignon", medium-maturing "Merlot" and early-maturing "Pinot Noir".In particular, the optimal zone for these four red wine varieties was centered in Xixia county of Yinchuan city, Pigeon Hill of Qingtongxia city and Baima Township of Zhongning County.For the two early-to-medium maturing white wine varieties of "Riesling" and "Chardonnay", the optimal and suitable zones were in the cool area of the central arid zone and the Qingshui River tributary.