Analysis of rainfall deficit and its impact on the Oltenia Plain vegetation using satellite images from the period 2000-2009

Análisis de los déficit de precipitación y su impacto sobre la vegetación de Oltenia Illano usando imágenes de satélite durante el período 2000-2009. Este investigación pretende evaluar el déficit de precipitaciones en temporada de verano y su impacto sobre la vegetación. Disminución de las precipitaciones en comparación con el valor medio representa el primer firme que precede el sequía. El análisis de los resultados de el Índice de Precipitación Estandarizado calculado por tres meses (SPI-3) y el mes (SPI-1), reveló que durante 2000-2009 en la Oltenia Illano tuvimos 5-6 años deficientes de precipitation de los cuales 2 años fueron calificados como los años secos y muy secos. Este déficit se observa en el análisis de satélite productos, NDVI y LAI obtenido por procesamiento de imágenes Spot-Vegetation y MODIS en la tercera década de cada mes de verano. Las imágenes de satélite revelan las diferencias temporales y espaciales de esta parametro meteorologico y el impacto que tiene en la vegetación de la llanura de Oltenia

Impact of drought on the productivity of agricultural crops within the Oltenia Plain, Romania

The purpose of this study was to evaluate the effect of moisture conditions on the productivity of agricultural crops within the Oltenia Plain, Romania at various time scales. The agro-databases contain the productions of winter wheat, maize and sunflower reported by the National Institute of Statistics and Agricultural Department for the period 1971-2013. The meteorological elements used were represented by the rainfall amount and air-temperature recorded at the six meteorological stations: Drobeta-Turnu Severin, Calafat, Băilești, Bechet, Craiova, Caracal and Turnu-Magurele. According to the SPI and De Martonne Index, the driest years, with low rainfall amounts, were 1983-1985, 1993, 2000, 2002, 2007 and 2012, with different degrees of water deficit. Moreover, the years with the lowest productions were recorded in the last half of the analysed period: 1993, 1996, 2000, 2002, 2007 and 2012. The impact of the drought variability of yield on the agricultural crops was evaluated using Bravais-Pearson correlations test, which was statistically significant in the last half of the reference period, while the correlation in the first half of the period it was not statistically significant. This result can be explained by the political system and the gradual degradation of the irrigation system, which determined the addiction on climatic conditions after '89 years

Applying a Complex Integrated Method for Mapping and Assessment of the Degraded Ecosystem Hotspots from Romania

To meet the global challenges of climate change and human activity pressure on biodiversity conservation, it has become vital to map such pressure hotspots. Large areas, such as nation-wide regions, are difficult to map from the point of view of the resources needed for such mapping (human resources, hard and soft resources). European biodiversity policies have focused on restoring degraded ecosystems by at least 10% by 2020, and new policies aim to restore up to 30% of degraded ecosystems by 2030. In this study, methods developed and applied for the assessment of the degradation state of the ecosystems in a semi-automatic manner for the entire Romanian territory (238,391 km2) are presented. The following ecosystems were analyzed: forestry, grassland, rivers, lakes, caves and coastal areas. The information and data covering all the ecoregions of the Romania (~110,000 km2) were analyzed and processed, based on GIS and remote sensing techniques. The largest degraded areas were identified within the coastal area (49.80%), grassland ecosystems (38.59%) and the cave ecosystems (2.66%), while 27.64% of rivers ecosystems were degraded, followed by 8.52% of forest ecosystems, and 14.05% of lakes ecosystems. This analysis can contribute to better definition of the locations of the most affected areas, which will yield a useful spatial representation for future ecological reconstruction strategy

Assessment of Soil Moisture Anomaly Sensitivity to Detect Drought Spatio-Temporal Variability in Romania

This paper will assess the sensitivity of soil moisture anomaly (SMA) obtained from the Soil water index (SWI) product Metop ASCAT, to identify drought in Romania. The SWI data were converted from relative values (%) to absolute values (m3 m−3) using the soil porosity method. The conversion results (SM) were validated using soil moisture in situ measurements from ISMN at 5 cm depths (2015–2020). The SMA was computed based on a 10 day SWI product, between 2007 and 2020. The analysis was performed for the depths of 5 cm (near surface), 40 cm (sub surface), and 100 cm (root zone). The standardized precipitation index (SPI), land surface temperature anomaly (LST anomaly), and normalized difference vegetation index anomaly (NDVI anomaly) were computed in order to compare the extent and intensity of drought events. The best correlations between SM and in situ measurements are for the stations located in the Getic Plateau (Bacles (r = 0.797) and Slatina (r = 0.672)), in the Western Plain (Oradea (r = 0.693)), and in the Moldavian Plateau (Iasi (r = 0.608)). The RMSE were between 0.05 and 0.184. Furthermore, the correlations between the SMA and SPI, the LST anomaly, and the NDVI anomaly were significantly registered in the second half of the warm season (July–September). Due to the predominantly agricultural use of the land, the results can be useful for the management of water resources and irrigation in regions frequently affected by drought