Using Landsat LST data to predict vineyard productivity anomalies: A case study in the Euganean Hills wine region, Italy

Abstract

Context and purpose of the study. In the current scenario of climatic variability, even though the vine (Vitis vinifera) is a species generally considered very fertile, the process of bud differentiation is particularly influenced by the weather trend not only of the current year but also of the previous one. To accurately determine this influence, buds’ fruitfulness data are usually compared with meteorological data collected in nearby weather stations but most of the time this is not possible. The study aimed to use Landsat-derived Land Surface Temperature (LST) data to develop a framework of single pixel-based LST climatology to assess bud’s fruitfulness anomalies in five Vitis vinifera L. varieties in the Euganean Hills wine district in Norther-East Italy.

Material and methods. A 23-year dataset (2000-2023) from Landsat 7, 8, and 9 imagery was used and for each pixel the seasonal (DJF, MAM, JJA, SON) and annual (ANN) LST climatology was computed. Five years of the following bud’s fruitfulness parameters: potential and real fruitfulness, n. blind buds, n. of sterile buds, were collected on ten vineyards of five Vitis vinifera varieties (Cabernet Sauvignon, Chardonnay, Merlot, Glera, and Moscato Giallo). Statistical analyses were performed to correlate the fruitfulness variables at each vineyard with the pixel-based LST anomalies, and risk maps were generated.

Results. Temperature anomalies influenced buds’ fruitfulness differently across grape varieties and areas. In Cabernet Sauvignon and Chardonnay, higher summer temperatures in the previous summer were linked to lower bud fruitfulness, while in Glera increased fruitfulness under similar conditions was observed. Warm winter temperatures increased blind and sterile buds in certain varieties. Risk maps indicated that the Central and Northeast areas were more susceptible to temperature variability, especially during winter and spring, with late frosts posing a significant risk. The results suggest that using LST data in vineyard management can aid in reducing the unfavourable impacts of temperature fluctuations. Vineyard productivity and sustainability can be improved by employing adaptive approaches, such as relocating varieties to sites with cooler microclimates, adjusting irrigation, or using shading techniques.