They use aerial systems tripulados and no tripulados, with sensors to attract images in the visible rank and no visible

Researchers of the Public University of Navarra collaborate with Tracasa and AIN in a project on cartography of precision applied to the management vitivinícola. With the use of optical sensors-electronic on aerial systems no tripulados (UAS) and tripulados (aeroplane), purchase images multi-spectral of big precision that contribute useful information for the back handle of the vineyards.

To obtain precise data of the vineyards, the researchers have had three sources of information: the aerial images purchased by the aeroplane of TRACASA; the images attracted by means of autonomous flights by an aerial system no tripulado (UAS by his acronyms in English 'Unmanned Aircraft Systems') developed by AIN, and the data registered by a sensor of field (CropCircle) that, joined up to a 4x4, allows to obtain information of the rows of vineyard in the 6 plots of Cellar Otazu object of study.

The taking of images realizar during the envero (when the grape is changing of colour), roughly a month before the vintage. “In addition to the images attracted by the aeroplane, can have the camera multiespectral integrated by AIN in his UAS allows us purchase images to a lot of less height, with greater space resolution –explains the main researcher, María González of Audícana–. Beside this, for those who work in agriculture is very important can have of the images in the precise moment, without having to expect to receive images of satellite whose free acquisition of clouds and in date, can not guarantee”.

Map of zoning of a plot: zones of high or low vegetative vigour and rows of vineyards numbered.

The images multiespectrales obtain thanks to able sensors to attract information no only in the rank of the visible but also of the infrared near, no visible. “This is essential because we can have information of how a vegetal cover reflects the solar radiation to distinct wavelengths. We know that when a vegetal cover is very vigorosa, very green, reflects little in the red and a lot in the infrared near; and the other way around: when it is little vigorosa because it is missing him water, nutrients, etc. tends to reflect more in the red and less in the infrared”. With these data, after the corresponding processing and adjust of images, the researchers can create precise maps of vegetative vigour of the vineyards.

The general aim of the project is to generate new services of cartography of precision for concrete applications. In this case, they selected six plots of distinct varieties (Chardonnay, Merlot, Cabernet Sauvignon and Tempranillo). Once obtained the images, in less than ten days the researchers can offer to the viticultor a map detailed of the plot, with specification of the zones and rows of vineyards with high or low vigour. “One of the appearances that value the cellars is that the grape that go in was homogénea, that do not mix , for example, grape with a lot of acidity with another that it was very different –signals González of Audicana–. With the information of these maps can, for example, decide vendimiar of separate form: the grape of the zones with greater vegetative vigour on the one hand and the rest by another”.

Image of the UAS used in the project.

Besides, during the years 2012 and 2013 the researchers carried out samplings of field to analyse distinct parameters so much of the vineyards as of the pertinent grape of these: likely alcoholic degree and total acidity of the grape, performance of the vineyards, weight of poda of the vineyards, section of trunk and lampshades, physical analysis-chemical of the floors, humidity of the floor, etc. “Is necessary to take into account that with the images obtained can know how are the vineyards, but to the cellar interests him know how is the pertinent grape of these vineyards. With these samplings wanted to contrast if the fact that some zones have more vigour that others, marks differences in the characteristics of the grape produced, and therefore, in his quality”.

The results of the sampling indicated that there are plots where the pertinent grape of the zones of high vigour and the pertinent of zones of low vigour was distinct, presented half values of alcoholic degree and different acidity. “This was very clear in the plot of Merlot, where there were significant changes. Also we saw that on a floor, of equal composition and nutrients, existed zones with distinct vegetative vigour; this, to judge by the measurements that realizar in 2013, seems to be motivated by the distinct capacity of the floor to retain water”.

The researchers of the UPNA that have participated in the project: Amaya Izaguirre (izda.), María González of Audicana and Jesús Álvarez.

This study has allowed also to the cellar know which can be good points of sampling. “Usually they muestrean in strains selected at random. However, facilitate them good points of sampling, representative of a bigger zone, involves to provide them an useful and valuable information of face to schedule his own measurements and controls of maduration, evolution, etc.”.

Finalised the work of field and after obtaining the first results, the researchers will finalise the project this year 2014 with the analysis of all the data and images and the obtaining of the definite conclusions.