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Volume XIX |

Agriculture drought assessment based on remote sensing, cloud computing, multi-temporal analysis. A case study: the Mostiștea Plain (Romania)

Abstract: Agricultural drought is one of the most important natural hazards worldwide, affecting a significant proportion of the global population. Earth Observation multi-spectral imagery satellites can provide a comprehensive picture of all land and sea areas of the Earth. Free of charge and open access imagery from missions such as Sentinel-2 provides high quality imagery with rapid high revisit period. Earth Engine© developed by Google Inc. provides the possibility to view and analyse petabytes of remote sensing data in archives that include more than thirty years of satellite imagery and scientific datasets. This paper proposes a cloud- based computation approach and analysis of multi-temporal, high resolution Sentinel-2 imagery on the Mostiștea Plain (Romania) in order to evaluate the agriculture drought. Custom javascript code was created in the Code Editor for calculating and analyzing remote sensing-based indices between 2017 and 2019. The results were classified into six classes: Water, No drought, Light drought, Moderate drought, Heavy drought, Severe drought. According to the classification, the southern half of Mostiștea Plain was the most affected area by a heavy agricultural drought during 2017-2019 period.

Volume XV |

Shape characteristics of fluvial islets based on GIS techniques. A case study: the Danube’s islets between Giurgiu and Olteniţa

Abstract: This study aims to quantitatively characterize shape parameters of fluvial islets using GIS techniques. There were eight metrics selected for the analysis. For the automation of the workflow, all processing functions were joined into a single graphical model. For this case study we selected the Danube sector situated between the cities Giurgiu and Oltenita. We chose to track the evolution of the fluvial islets’ shapes from 1864 to 2010. Information was extracted from historical data sources such as maps and ortophotoplans. The graphical model created was run for each studied year.The results show major changes in the aspect of fluvial islets along the Danube reach. Between 1864 and 2010 the number of islets slightly increased with the total area ranging from 21.19 kmp to 27.96 kmp. In the period studied, the shape turned from a rounded aspect to a more elongated one. Knowledge of the information on the shape of those landforms is relevant for river restoration strategies, nature conservations of islets and maintenance of the protected habitats.