Lucian Sfîcă

Winter Presence of Long-Legged Buzzard (Buteo Rufinus) in Moldova (Romania)

Abstract Long-legged Buzzard (Buteo rufinus) is a medium sized bird of prey which is known as a breeding species for Romania. In the last years it started to become a common wintering presence in the south-eastern part of Romania (Dobrogea) but it was also recorded in the more northern areas (Moldova) during the cold season. Its presence in Moldova, during the winter period, was recorded in large river valleys, with agricultural lands or grasslands and with trees or timber poles, which are used for perching. Long-legged Buzzard is a new presence for Moldavian winter seasons and it could be observed only in warm periods of winter, when the daily mean temperature is above 0°C. The wintering places are maintained not only for all winter period, but also for the next years. This behaviour could be explained by its territorial fidelity, which was recorded also in other European buzzard species during the winter period. Résumé Buse féroce (Buteo rufinus) est un oiseau de taille moyenne de proie qui est connu comme une espèce nicheuse pour la Roumanie. Dans les dernières années, il est devenu une présence commune au cours de l’hiver au sud-est de la Roumanie (Dobroudja), mais il était également enregistré dans les régions du Nord (Moldavie) pendant la saison froide. Sa présence en Moldavie, pendant la période hivernale, a été enregistrée dans les vallées des grands fleuves, les terres agricoles et les prairies avec des arbres ou des poteaux en bois ou qui est utilisé pour se percher. Buse féroce est une nouvelle présence pour les saisons d’hiver en Moldavie et il ne peut être observé que dans les périodes chaudes de l’hiver, lorsque la température moyenne quotidienne est supérieure à 0°C. Les lieux d’hivernage sont maintenus non seulement pour toute la période d’hiver, mais aussi pour les années suivantes. Ce comportement peut être expliqué par sa fidélité territoriale, qui a été observé également pour le Buse variable. Rezumat Şorecarul mare (Buteo rufinus) este o specie de pasăre răpitoare de zi, de dimensiuni medii, ce cuibăreşte cu regularitate în Dobrogea. Cuibăritul speciei a fost semnalat începând cu 2007 şi în Moldova. Deşi figurează în literatura de specialitate ca specie migratoare, prezenţa ei în perioada de iarnă a început să devină tot mai comună, în special pentru partea de sud-est a ţării. În Moldova specia a fost observată, pentru prima dată în perioada de iarnă, în anul 2007. De atunci am început să urmărim prezenţa speciei şi pentru această parte a ţării. Până în prezent au fost înregistrate 15 observaţii în timpul sezonului rece (noiembrie - februarie) pentru întreaga arie de studiu. Din datele pe care le deţinem, pentru aria de studiu, putem spune că şorecarul mare se întâlneşte cu precădere în văile largi ale râurilor, unde predomină terenurile agricole şi pajiştile. Altitudinea medie înregistrată pentru observaţiile din Moldova este de 70 m. Având în vedere faptul că este o specie ce preferă climatul mediteranean, prezenţa ei în timpul sezonului rece este strâns legată de perioadele de încălzire a vremii, pe parcursul cărora temperaturile diurne depăşesc 0oC. În ultimele decenii, frecvenţa zilelor cu temperaturi maxime de peste 0oC în timpul iernii se află într-o creştere semnificativă din punct de vedere statistic (Clima României, 2008). Şorecarul mare pare că manifestă o preferinţă pentru anumite teritorii de iernare, deoarece a fost observat în aceleaşi arii nu doar pe durata unui sezon ci pe întreaga perioadă de studiu. Fidelitatea teritorială a fost înregistrată şi la celelalte specii de şorecari din Europa însă, pentru a putea demonstra cu certitudine acest comportament în cazul şorecarului mare, sunt necesare studii amănunţite şi pentru perioade mai lungi.

Common Buzzards Buteo buteo Wintering in Eastern Romania: Habitat Use and Climatic Factors Affecting their Abundance

Abstract. The Common Buzzard is a partial migrant in Eastern Europe, but its wintering densities are poorly known for this area due to a low number of studies. However, its migration patterns and wintering grounds can be affected by climate change with local fluctuations in numbers linked to weather conditions. Between 2010 and 2015 we annually carried out 15 transects/winter month in order to count the wintering population of Common Buzzards across Eastern Romania to look for climatic factors explaining variation in wintering density. Transects were controlled during two weeks from the end of the month, each covering a distance of 40 km, outlining the broadest winter monitoring of raptors in Central and Eastern Europe. Road survey was used, with a car driving at a low speed, and two observers counting birds, recording distance and habitat where birds occurred. In analyses, in addition to local weather data also 9 indices integrating weather conditions across longer time windows and larger areas were included. The wintering density calculated for the five-year period was 0.539 individuals/km2 fluctuating during the winter seasons with a possible cyclic pattern. The Buzzards selected pastures and herbaceous vegetation associations for hunting across their wintering grounds. Common Buzzard numbers fluctuate during the winter season (highest in December). They are positively influenced by rising solar flux and negatively by the low North Eastern Europe temperatures and Arctic Oscillation Index recorded within 14 days before the survey, which drive birds to southern wintering areas. These weather conditions (high pressure and low temperatures) represent the onset of the Siberian Anticyclone, a regular, annual weather system that occurs in Eastern Europe every winter.

Three Years of Observations on Global Solar Radiation at Mădârjac Weather Station (270 m) - Central Moldavian Plateau

Abstract This study is based on 3 years of hourly observations of global solar radiation (2014-2016), at a new weather station installed in the region of Central Moldavian Plateau, at Mădârjac (47.05°N, 27.25°E, 270 m). The main characteristics of annual, monthly and daily regime of global radiation were emphasized using for comparison similar data from Iașioficial weather station. Smaller annual amount of global solar radiation than those observed in previous studies were observed, reaching 4734 MJ/m2 in Iași and 4454 MJ/m2 in Mădârjac. An altidudinal gradient of global solar radiation close to 140 MJ/m2 was identified for the hilly region of Moldova. Despite the overall higher values in Iași, 30% of days indicates higher values of this parameter at Mădârjac weather station. These results can be used for the evaluation of the photo-voltaic potential in the region, but also to understand the altitudinal differences of solar radiation in the hilly region in Moldavia, since the only long-range actinometric stations from this part of Romania, Iași and Galați, are located at low altitudes.

The Distribution of the Monthly 24-Hour Maximum Amount of Precipitation in Romania According to their Synoptic Causes

In the present paper we have analysed the synoptic conditions generating the maximum amount of precipitation within 24 hours in Romania. This study is based on the analysis of daily weather maps from different archived sources and also on the processing of ROCADA data set concerning the daily amount of precipitation in Romania (1961-2013). Some main weather types (WTs) specific for the occurrence of high amount of precipitation in Romania were established, and the daily recording of the maximum amount of precipitation for 24 hours at monthly level was assigned to one of the defined WTs. Out of the total of 312 days analysed from the synoptic point of view, a total of 133 days (42.6%) were characterized by high atmospheric instability. The larger part of them (100 days) were determined by cold air advections associated to long-wave troughs propagating from North Atlantic towards the centre of European continent, while the rest of 33 days were generated by cut-off lows identified in the middle and upper troposphere in South-East Europe. As well, 124 days (39.7%) were assigned to Mediterranean cyclones transiting the region of Romania and 55 days (17.7%) were associated with Atlantic cyclones activity. The climatology of each synoptic type is presented. Also, regional and seasonal disparities are described using proper interpolation methods. Key-words: Precipitation extremes, ROACADA database, Mediterranean cyclones, Cut-off lows Long-wave troughs.

FREQUENCY OF THERMAL INVERSIONS BETWEEN SIRET AND PRUT RIVERS IN 2013

Abstract Temperature inversions represent complex phenomena, specific for depression forms of relief which introduce changes in vertical zoning (Apăvăloae, Apostle, Pîrvulescu, 1986 by stable air stratification (Erhan, 1981), because of their morphological features, this is due to the interdependence of general movement and characteristics of the active surface, being the cause of their production (Apăvăloae, et. al., 1984, 1986, 1987). The generation of thermal inversions, their intensity and frequency is a consequence of altitude topography, morphology, fragmentation, orientation and degree of closure to external drives. (Apăvăloae, Apostle, Pîrvulescu, 1988). Thermal inversions represent complex phenomena, specific to depression landforms that introduce changes within the vertical zoning (Apăvăloae, Apostol, Pîrvulescu, 1986) by stable air stratification (Matveev, 1958, Erhan, 1981, Yinghui Liu, 2002) where vertical thermal gradient is negative (Matveev, 1958), due to their morphological features, also as a consequence of the interdependance of general circulation and characteristics of the active surface, the cause of their generation (Apăvăloae, et. al., 1984, 1986, 1987).