Identifying Ideal Winegrowing Areas in New Zealand
Predictive Modelling Approach
The aim of the projects was to generate predictive models to identify areas that are ideal for growing good wine producing grapes using existing vineyards as a guide. These models were generated using spatial data modelling techniques.
The modelling techniques can be used to prioritise the potential locations for the establishment of new vineyards in New Zealand or to prioritise grape varieties to specific sites. Other industries could also benefit from the techniques such as fruit growers (e.g. apples, cherries, kiwifruit), or even more exotic species (tea, coffee, spices).
The weights of evidence technique has been used in our studies to integrate and interpret the available data for the New Zealand and then the Hawke’s Bay Region to identify optimum places to grow grapes for the production of wine.
The New Zealand Wine Model
The New Zealand winegrowing industry is spread over several regions throughout the country. Over 40 percent of the national grapevine area is in the Marlborough region, with 24 per cent in the Hawke's Bay and 14 per cent in the Gisborne region. Other grape production areas, including the Wairarapa, Nelson, Canterbury and Otago regions, together represent 13 per cent of the New Zealand vine area.
The New Zealand winegrowing industry has changed significantly over the past decade. Both the total grapevine area and the vine producing area have increased dramatically and the Wine Institute expects the total grapevine area to expand by around 1000 hectares per annum over the next five years and has predicted a significant rise in wine production.
We have developed a first-pass scoping study to identify potential new sites for growing grapes. A number of features important for grape growth have been indentified and tested in this project. Properties defined as having a probable impact on the success of a vineyard included namely: climatic factors, soil properties, location features and social factors.
The Hawke's Bay Wine Model
The aim of the Hawkes Bay Wine Model was to generate a predictive model that identified optimum areas to grow grapes for the production of wine in one of the ideal regions which were identified in the New Zealand Model.
The Hawke’s Bay Wine Model was a pilot study which used very coarse scale data that was available at that stage. The weights of evidence modelling method requires a set of training data to test the correlation between the existing vineyards and the predictive map being tested. A selection of vineyards already established in the Hawke’s Bay region was used as training points. The study area for the model covered Central Hawke’s Bay, Hastings and Napier City; a large area that contains both excellent and poor grape growing areas.
For each model was developed a suitability map, using weights of evidence techniques, which included the themes that had the best regional coverage and a good spatial correlation with the known award-winning vineyards. The suitability maps in the sidebar clearly highlights the most favourable wine growing areas in New Zealand and in the Hawkes Bay region; the highly suitable areas for grape growing are shown in red. The model was successful at the scale of the data used and managed to highlight other existing vineyards that weren’t included in the modelling process.