The salinization of the coastal aquifers is a worldwide issue affecting many delta areas. The low-lying Ravenna plain (Italy) is strongly drained, highly subsident with the only topography present in dune and paleodune areas. In this context, the underlying phreatic aquifer is completely brackish and salty and the only fresh water lenses are located below the historical pinewoods (paleodune) and along the actual dune belt. Changes in the water salinity are able to induce variations in the leaves properties and vegetation cover, recognizable by surveys carried out in different spectral bands. Furthermore, a comparison between remote sensing satellite images with different resolution, ASTER and Worldview-2, was carried out using the Normalized Difference Vegetation Index (NDVI). Inside the San Vitale pinewood (Ravenna, Italy), different sample areas were selected within the Thermophilic Deciduous Vegetation because it covers more than 80% of the studied pine forest. The NDVI, calculated with traditional bands, identified the same stressed areas shown by both satellite data. Instead, using the new Red Edge band of the Worldview-2 image, a greater correlation between NDVI and groundwater salinity was detected
ASTER and WorldView - 2 satellite data applications for recognition of salt water intrusion on forest vegetation
DE GIGLIO, MICHAELA;GREGGIO, NICOLAS;BARBARELLA, MAURIZIO
2014
Abstract
The salinization of the coastal aquifers is a worldwide issue affecting many delta areas. The low-lying Ravenna plain (Italy) is strongly drained, highly subsident with the only topography present in dune and paleodune areas. In this context, the underlying phreatic aquifer is completely brackish and salty and the only fresh water lenses are located below the historical pinewoods (paleodune) and along the actual dune belt. Changes in the water salinity are able to induce variations in the leaves properties and vegetation cover, recognizable by surveys carried out in different spectral bands. Furthermore, a comparison between remote sensing satellite images with different resolution, ASTER and Worldview-2, was carried out using the Normalized Difference Vegetation Index (NDVI). Inside the San Vitale pinewood (Ravenna, Italy), different sample areas were selected within the Thermophilic Deciduous Vegetation because it covers more than 80% of the studied pine forest. The NDVI, calculated with traditional bands, identified the same stressed areas shown by both satellite data. Instead, using the new Red Edge band of the Worldview-2 image, a greater correlation between NDVI and groundwater salinity was detectedI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
