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UID:pretalx-foss4g-it-2023-CVTH9W@talks.staging.osgeo.org
DTSTART;TZID=GMT:20230612T151500
DTEND;TZID=GMT:20230612T153000
DESCRIPTION:Precision viticulture aims to enhance quality standards of wine
  production by improving vineyard management. In this framework\, satellit
 e optical remote sensing has already proved to be effective for mapping ve
 getation behavior in space and time. These maps\, properly processed\, are
  useful to optimize agronomic practices improving wine production/quality 
 and mitigating environmental impacts. Nevertheless\, vineyards represent a
  challenge in this context because grapevine canopies are discontinuous\, 
 and the observed reflectance signal is affected by background. In fact\, s
 atellite imagery ordinarily provides spectral measures with medium-low geo
 metric resolution (≥ 100 m2). Therefore\, spectral mixture between grape
 vine canopies\, grass and soils is expected within a satellite-derived ref
 lectance pixel and not considering this problem can deeply affect deductio
 ns based on this data. In this work\, Sentinel-2 (S2) NDVI maps (10 m reso
 lution) were computed and compared to the ones obtained from DJI P4 multis
 pectral UAV over a vineyard sizing 1.5 ha and located in Piemonte region (
 NW Italy). The proportion of row and inter-row (α(x\,y) and 1-α(x\,y)) w
 ithin S2 pixel was computed and mapped classifying DJI photogrammetry poin
 t cloud. Involving α(x\,y) and S2 NDVI values\, reversing spectral unmixi
 ng system was defined solving for two average endmembers NDVI values (row 
 and inter-row) using a moving window (21x21 pixels) least squares approach
 . Results were compared at S2 pixel-level to the average ones computed fro
 m DJI\, showing a MAE of 0.15 and 0.10 of row and inter-row NDVI respectiv
 ely.
DTSTAMP:20260427T163743Z
LOCATION:Sala Biblioteca @ PoliBa
SUMMARY:Pixel Mixture Issue in Mapping Vineyard Phenology. A Possible Solut
 ion Based on Sentinel-2 Imagery and Local Least Squares - Enrico Borgogno-
 Mondino\, Francesco Parizia\, Federica Ghilardi\, Alessandro Farbo\, Filip
 po Sarvia\, Samuele De Petris
URL:https://talks.staging.osgeo.org/foss4g-it-2023/talk/CVTH9W/
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