Vineyard Management to Meet Grape Quality Specifications
project 1.1.1
Precision Viticulture - Investigating the Utility of Precision Agriculture Technologies for Monitoring and Managing Variability in Vineyards
Vineyards vary substantially in the quantity and quality of grapes they produce. Yield and various measures of quality are known to vary widely within blocks and along rows. Two consequences of this are the uncertainty in the prediction of yield, and delivery of grapes of inconsistent quality to the winery.
Yield uncertainty obstructs precise scheduling by winemakers faced with an increasing mismatch between the tonnage of grapes to be crushed and the crushing and storage capacity of the winery. Meanwhile, variation in fruit quality, and the resultant acceptance of 'average' quality from whole vineyards limits the opportunity to maximise the production of premium quality wines.
This project aims firstly to quantify the nature of within-vineyard variability and secondly analyse soil and associated vineyard properties to identify possible causes of such variation with a view to assessing the feasibility of crop response to targeted management.
It will also be investigated whether the utility of high-resolution (airborne) remote sensing as a means of monitoring variability in vine canopies, both for directing in-field sampling to ascertain causes of variability and as a means of quantifying variations in yield and quality attributes.
Resources to help you
As part of Project 1.1.1, Rob Bramley and Susie Williams have produced an easy to read guide (2.6mb PDF) that takes you through the necessary steps for the production of robust grape yield maps.
This addendum updates the original grape yield mapping protocol with respect to data cleaning and the currently available grape yield monitors. Bramley, R.G.V 2005 (PDF, 113 kB) [download]
A poster (4.4mb PDF) describing the yield map guide was presented at the 3rd European Conference on Precision Agriculture, Montpellier, France.
Recent papers to view or download
11th Australian Wine Industry Technical Conference, Adelaide 2001, Workshop W14, Precision Viticulture - Principles, opportunities and applications (4.1Mb PDF)
Presenters: R Bramley, T Proffitt, R Hamilton, J Shearer, D Ormesher, D Lamb, J Taylor
Bramley, R.G.V. 2001. Progress in the development of Precision Viticulture - Variation in Yield, Quality and Soil Properties in Contrasting Australian Vineyards (3.3Mb PDF) In: Precision tools for improving land management. (Eds L D Currie and P Loganathan). Occasional report No. 14. Fertilizer and Lime Research Centre, Massey University, Palmerston North. In press. This was an invited keynote address to the 14th Annual Workshop of the Fertilizer and Lime Research Centre - Precision tools for improving land management.
Additional Reading
- Bramley, R.G.V. and Proffitt, A.P. 1999. Managing variability in viticultural production. Grapegrower and Winemaker July 1999, 11-16.
- Lamb, D. W. 1999. Monitoring vineyard variability from the air, Australian Viticulture, 3 (6), 22-23.
Other related websites
project 1.1.1 - update
Vintage 2002 demonstrated that the HarvestMaster winegrape yield monitor does not perform adequately when average yields are of the order of 2.5 t/ha or less. In contrast, the performance of the new Farmscan machine (one of which was purchased by the project) was unaffected by the low yields experienced in 2002.
A digital elevation model of the Coonawarra field site, together with soil depth and texture information has been used to demonstrate that yield variation in this site is primarily driven by availability of soil moisture.
Methodology for evaluating the temporal stability of patterns of vineyard variation are currently being developed and will form the basis for data analysis during years five to seven.
Calibrated multispectral imagery at 1.5m, 1.0 m, 50 cm and 25 cm spatial resolution, acquired for both Riverina sites at bud-burst, early flowering, veraison, post veraison & pre-harvest in 2001-2002 have now been analysed. As in earlier work completed for the Coonawarra site, significant relationships were also found between canopy descriptors and numerous vine and fruit parameters including grape yield, pH, T.A., colour and phenolics.
An evaluation of the potential of field-based NIR for estimating trace-element status in vines is currently underway. Spectro-radiometer readings of vine leaf reflectance were acquired from the CSU (Riverina) site in conjunction with detailed leaf and Petiole chemical assays (60 sites, 5 leaves per site). Preliminary chemometric analyses of the data have commenced, involving David Lamb (UNE, Armidale), Mark Gishen (AWRI) and Ralph Brown (University of Guelph, Ontario Canada).
David Lamb, Ralph Brown (University of Guelph, Canada) and Kevin Powell, (DNRE Vic) also conducted preliminary radiometric measurements of leaf spectra from both phylloxera-free and phylloxera-infected vines in South-East Victoria with a view to determining whether remote or proximal sensing could be used to identify phylloxera. Preliminary results suggest that leaf spectral signature alone may be able to positively identify phylloxera infected vines, but could not positively identify phylloxera-free vines.
A time-sequence of colour-infrared photographs are being analysed to evaluate their use for detecting phylloxera in vineyards, based on creating difference-images of successive seasons. Sequences of images from five seasons (1996-2001) of two King Valley vineyards are being analysed. Preliminary results indicate that multi-temporal imagery may be useful for phylloxera detection, providing stringent image calibration and registration procedures are followed.
Remote sensing images of a Cabernet Sauvignon block located at Wagga Wagga were processed using the VineCrawler algorithm developed by Andrew Hall and the vines segmented into six different zones of photosynthetically-active biomass (PAB). The grapes were separately harvested and made into separate batches of wine following the Australian Wine Research Institute standard red-winemaking protocol. The wine was tasted by a panel of 56 tasters and significant differences were noted in various flavour identifiers in all batches. Some aspects of the link between canopy architecture (as perceived in the processed imagery) and wine flavour are currently being investigated.
Additional white winegrape field sites were imaged in Griffith, in support of the Carbohydrate Reserve Project (Holzapfel) and this data is currently being analysed. A Cabernet Sauvignon field site was established in Armidale (Northern NSW) for the continuation of the remote sensing of red-winegrape quality (to be continued in 2004-7).
Andrew Hall is in the final stages of writing his thesis.
