terclim by ICS banner
IVES 9 IVES Conference Series 9 Variations of soil attributes in vineyards influence their reflectance spectra

Variations of soil attributes in vineyards influence their reflectance spectra

Abstract

Knowledge on the reflectance spectrum of soil is potentially useful since it carries information on soil chemical composition that can be used to the planning of agricultural practices. If compared with analytical methods such as conventional chemical analysis, reflectance measurement provides non-destructive, economic, near real-time data. This paper reports results from reflectance measurements performed by spectroradiometry on soils from two vineyards in south Brazil. The vineyards are close to each other, are on different geological formations, but were subjected to the same management. The objective was to detect spectral differences between the two areas, correlating these differences to variations in their chemical composition, to assess the technique’s potential to predict soil attributes from reflectance data.To that end, soil samples were collected from ten selected vine parcels. Chemical analysis yield data on concentration of twenty-one soil attributes, and spectroradiometry was performed on samples. Chemical differences significant to a 95% confidence level between the two studied areas were found for six soil attributes, and the average reflectance spectra were separated by this same level along most of the observed spectral domain. Correlations between soil reflectance and concentrations of soil attributes were looked for, and for ten soil traits it was possible to define wavelength domains were reflectance and concentrations are correlated to confidence levels from 95% to 99%. Partial Least Squares Regression (PLSR) analyses were performed comparing measured and predicted concentrations, and for fifteen out of 21 soil traits we found Pearson correlation coefficients r > 0.8. These preliminary results, which have to be validated, suggest that variations of concentration in the investigated soil attributes induce differences in reflectance that can be detected by spectroradiometry. Applications of these observations include the assessment of the chemical content of soils by spectroradiometry as a fast, low-cost alternative to chemical analytical methods.

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Poster

Authors

Adriane B. Thum1,2, Diniz C. Arruda2 and Jorge R. Ducati2

1Escola Politécnica, Universidade do Vale do Rio dos Sinos, São Leopoldo, Brazil
2Centro Estadual de Pesquisas em Sensoriamento Remoto e Meteorologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil

Contact the author

Keywords

topsoil reflectance, spectroradiometry, Vis-NIR spectroscopy, wine terroirs

Tags

IVES Conference Series | Terclim 2022

Citation

Related articles…

Characterizing the molecular basis of the differences in aromatic precursors found in commercial clones of Vitis vinifera cv. Tannat

Uruguay is known for the production of Tannat wines, which is a neutral variety from an aroma point of view, but capable of providing aromatic precursors that are of interest in the production of wines for ageing. The main aromatic precursors present are glycosidic compounds and carotenoids. The contribution of carotenoid degradation by-products such as norisoprenoids to wine aroma is fundamental, as they are associated with pleasant aroma descriptors and very low olfactory perception thresholds. Several factors have been shown to influence carotenoid concentrations in grapes, such as cultivar, climatic conditions, viticultural region, plant water status, exposure to sunlight and ripening stage.

Impact of some agronomic practices on grape skins anthocyanin content

Wine colour is the first quality characteristic to be assessed, especially regarding red wines. Anthocyanins are very well known to be the main responsible compounds for red wine colour. Red cultivars can synthesize and accumulate anthocyanins in berry skin to express their colour. However, anthocyanin accumulation is often influenced by a series of factors, such as genetic regulation, phytohormones, environmental conditions and viticultural management.

Evaluation of “Accentuated cut edges” technique on the release of varietal thiols and their precursors in Shiraz and Sauvignon blanc wine production

Accentuated cut edges (ACE) is a novel grape crushing technique used sequentially after a conventional crusher to increase the extraction rate and content of polyphenolics, as shown for Pinot noir wine. This inspired us to apply the technique during Shiraz and Sauvignon blanc winemaking, primarily to assess its impact on the extraction of varietal thiol precursors in grape must/juice and formation of varietal thiols in the resultant wines

Biomarker-based phenotyping of grapevine (vitis spp.) resistance to plasmopara viticola reveals interactions between pyramided resistance loci

Grape downy mildew, caused by plasmopara viticola, is one of the main diseases affecting viticulture worldwide and its control usually relies on frequent sprays with agrochemicals. Grapevine varieties resistant to p. Viticola represent an effective solution to control downy mildew and reduce the environmental impact of viticulture. Loci of resistance to p. Viticola (Rpv) have been introgressed from wild vitis species and some of them, like Rpv1, Rpv3.1 and Rpv10, are currently the most utilized genetic resources in grape breeding.

Biotic and abiotic factors affecting physiological aspects underlying vegetative vigour in two commercial grapevine varieties

Grapevine vigour, defined as the propensity to assimilate, store and/or use non-structural sugars for allowing fast growth of shoots and producing large canopies[1], is crucial to optimize vineyard management. Recently, a model has been proposed for predicting the vigor of young grapevines through the measurement of the vegetative growth and physiological parameters, such as water status and gas exchange[2]. Our objectives were (1) to explore the influence of the association of two grapevine varieties (Tempranillo and Cabernet Sauvignon, grafted onto R110 rootstocks) with arbuscular mycorrhizal fungi (AMF) on the vegetative vigour of young plants; and (2) to assess the effect of environmental factors linked to climate change on the vegetative vigour of Cabernet Sauvignon.