BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

Sustainable and ecosystem-based marine spatial planning is a priority of Pacific Island countries basing their economy on marine resources. The urgency of management coral reef systems and associated coastal environments, threatened by the effects of climate change, require a detailed habitat mapping of the present status and a future monitoring of changes over time. Here, we present a remote sensing study using free available Sentinel-2 imagery for mapping at large scale the most sensible and high value habitats (corals, seagrasses, mangroves) of Palau Republic (Micronesia, Pacific Ocean), carried out without any sea truth validation. Remote sensing ‘supervised’ and ‘unsupervised’ classification methods applied to 2017 Sentinel-2 imagery with 10 m resolution together with comparisons with free ancillary data on web platform and available scientific literature were used to map mangrove, coral, and seagrass communities in the Palau Archipelago. This paper addresses the challenge of multispectral benthic mapping estimation using commercial software for preprocessing steps (ERDAS ATCOR) and for benthic classification (ENVI) on the base of satellite image analysis. The accuracy of the methods was tested comparing results with reference NOAA (National Oceanic and Atmospheric Administration, Silver Spring, MD, USA) habitat maps achieved through Ikonos and Quickbird imagery interpretation and sea-truth validations. Results showed how the proposed approach allowed an overall good classification of marine habitats, namely a good concordance of mangroves cover around Palau Archipelago with previous literature and a good identification of coastal habitats in two sites (barrier reef and coastal reef) with an accuracy of 39.8–56.8%, suitable for survey and monitoring of most sensible habitats in tropical remote islands.

We present here a novel method to assess coastal vulnerability to tsunami based on GIS (Geographical Information System), ASTER imagery (Advanced Spaceborn Thermal Emission and Reflection Radiometer) and SRTM-3 elevation model (Shuttle Radar Topography Mission-3). We developed this method within the CRATER project (Coastal Risk Analysis for Tsunamis and Environmental Remediation) and applied it on the whole western coast of Thailand. As result, we generated a set of vectorial vulnerability maps with a geometrical resolution of 90m (scale 1:450 000). This approach provides a low-cost and quick tool to analyse extended coastal tracts, and prioritize investments for prevention measures or for further high-resolution analysis. Un nuovo approccio (metodo CRATER) per la stima a scala regionale della vulnerabilità a tsunami mediante immagini ASTER Riassunto Il lavoro presentato introduce un nuovo metodo per la stima della vulnerabilità costiera a tsunami, basato sul GIS (Geographical Information System), sull'impiego di immagini ASTER (Advanced Spaceborn Thermal Emission and Reflection Radiometer) e modelli di elevazione SRTM-3 (Shuttle Radar Topography Mission-3). Il metodo è stato sviluppato nell'ambito del progetto CRATER (Coastal Risk Analysis for Tsunamis and EnvironmentalRemediation) ed applicato all'intera costa occidentale della Tailandia. I risultati consistono in un set di mappe vettoriali della vulnerabilità con risoluzione di 90m (scala 1:450 000). Tale approccio costituisce un mezzo relativamente economico e veloce per l'analisi di estesi tratti costieri e per la gestione di investimenti in misure di prevenzione o in ulteriori analisi ad alta risoluzione. Tsunami, Vulnerabilità costiera, ASTER, GIS, Uso Suolo. Dall'Osso et al. Tsunami vulnerability at the regional scale: the CRATER method Parole chiave:

Soil salinization is a form of topsoil degradation due to the formation of soluble salts at deleterious levels. This phenomenon can seriously compromise vegetation health and agricultural productivity, and represents a worldwide environmental problem. Remote sensing is a very useful tool for soil salinization monitoring and assessment. In this work we show some results of a study aimed to define a methodology for soil salinity assessment in Iraq based on SPOT 5 imagery. This methodology allows the identification of salinized soils primarily on bare soils. Subsequently some soil salinity assessment can be done on vegetated soils. On bare soil the identification of salt is based on spectral analysis, using the Minimum Noise Fraction transformation and several indexes found in literature. In case of densely vegetated soils the methodology for the discrimination of salinized soils has been integrated with the results obtained from the classification of vegetation coverage.

No abstract