Plant biodiversity hotspots mapping and prioritization in the Bulgarian floristic region Eastern Balkan Mountains

The main goal of the present study was to create a dynamic map of plant biodiversity hotspots of the Bulgarian floristic region Eastern Balkan Mountains. A GIS model, as well as a weighted value scheme for scoring each area, were created in order to identify and to prioritize the hotspots. A total number of defined hot spots of phytodiversity was 34. They were categorized into five classes, based on the cumulative weighted value scheme, and were indicated on the map using color scale. The territories into category I predominated, contrary to preceding investigations of the Black Sea coast and northeastern Bulgaria where category V predominated. In addition, an attempt to refine the borders of the floristic region was made.

Long-legged flies (Diptera: Empidoidea: Dolichopodidae) from the Balkan Mountains, Bulgaria, with first records for the Balkan Peninsula

The paper presents information about 35 dolichopodid flies collected from 12 localities in the Balkan Mountains at the territory of Bulgaria. Two species, Campsicnemus pusillus and Sciapus maritimus, are recorded for the first time in Bulgaria and on the Balkan Peninsula. Another nine ones are listed for the first time to the Balkan Mountains range.

Review of the ammonite genus Pseudokossmaticeras Spath, 1922 from the uppermost Campanian–lower Maastrichtian in Bulgaria

New data on the ammonite genus Pseudokossmaticeras Spath, 1922 have been obtained from several uppermost Campanian–lower Maastrichtian strata of the Fore-Balkan Mountains (Bulgaria). A review of the earlier Bulgarian records of the genus is also presented. The following species are here described and illustrated: Pseudokossmaticeras brandti (Redtenbacher, 1873), P. galicianum (Favre, 1869), P. muratovi Michailov, 1951 and P. tercense (Seunes, 1892). Our newly obtained ammonite records were constrained by the inoceramid zonation that has recently been proposed for successions of the Fore-Balkan area. Hence, the Bulgarian data are of importance for correlation with other occurrences of Pseudokossmaticeras across Europe.

Review of the ammonite genus Pseudokossmaticeras Spath, 1922 from the uppermost Campanian–lower Maastrichtian in Bulgaria

New data on the ammonite genus Pseudokossmaticeras Spath, 1922 have been obtained from several uppermost Campanian–lower Maastrichtian strata of the Fore-Balkan Mountains (Bulgaria). A review of the earlier Bulgarian records of the genus is also presented. The following species are here described and illustrated: Pseudokossmaticeras brandti (Redtenbacher, 1873), P. galicianum (Favre, 1869), P. muratovi Michailov, 1951 and P. tercense (Seunes, 1892). Our newly obtained ammonite records were constrained by the inoceramid zonation that has recently been proposed for successions of the Fore-Balkan area. Hence, the Bulgarian data are of importance for correlation with other occurrences of Pseudokossmaticeras across Europe.

F. Vovk’s Research on Ukrainians in Dobruja in the Context of Domestic Ukrainian Studies Achievements

The article defines the topicality of the ongoing study of the collection “Rare books with bookplates, inscriptions, and marginalia with the name of Fedir Vovk” from the Library Fund of the National Museum of the Ukrainian History as the source base for ethnology, ethnography, local lore, and Ukrainian studies. It characterizes the object of the research – Fedir Vovk’s scholarly investigation of Ukrainians in Dobrudja (the historical and geographical region between the Lower Danube and the central part of the Balkan Mountains in Bulgaria and Romania), which he conducted during his forced political emigration to Romania in the 1880s. The research is performed by the de visu method and based on two main sources – rare books, including the monograph “Transdanubian Sich (local memoirs and stories)” (1883) and the article “Ukrainian Fishery in Dobrudja” (1899). The research tasks that combine Ukrainian and book studies are based on the relevance of the discussion and its interdisciplinary sense. It has been generalized that the past of the Ukrainian community of Dobrudja can be illustrated in a certain diversity of its history and traditions, although relying on a very narrow historiographical basis besides Fedir Vovk’s research. It has been observed that Fedir Vovk did not only dedicate almost 10 years of his scholarly work to the search, collection, and preservation of the historical memory of his compatriots abroad but also aimed to find the traces of Zaporizhzhian Cossacks military (administrative) centers to study their memory about homeland, way of life, and traditions in a new complex local geographical, social, and political context. The article outlines the research prospects in the context of the mission set by bibliologists, historians, and experts in Ukrainian studies to develop “Professor F. Vovk’s Memory Department”, which was founded in the 1920s by his associates and suspended by the Great Terror.

Re-introduction of Griffon Vulture (Gyps fulvus) in the Eastern Balkan Mountains, Bulgaria – completion of the establishment phase 2010-2020

The current study presents and analyses the results from the recently completed 11-year-establishment phase, following the start of the local re-introduction of the Griffon Vulture (Gyps fulvus) in Kotlenska Planina SPA and Sinite Kamani Nature Park in the Eastern Balkan Mountains of Bulgaria in the period 2010-2020. As a result of the re-introduction efforts and release of 153 individuals, the Griffon Vulture has been successfully reproducing again in the Eastern Balkan Mountains since 2016, after more than 40-50 years of absence. At 2020, the local population consists of some 80 local and up to 80-115 birds, together with sojourn individuals. Amongst them, 23-25 breeding pairs, located in five different colonies and two more frequently used roosting sites. The current average productivity remains relatively low: 0.41 fledglings/territorial pair and fledging success of 0.61 fledglings/breeding pair between 2016 and 2020, but shows a trend to increase with time and the growing experience of the young locally re-introduced population. The mortality confirmed between 2010-2021 accounts for 33%, mostly due to electrocution as a post-release effect in the first six months following their release. Our data show that the newly established population in the Eastern Balkan Mountains mostly forages on feeding sites, having a comparatively small 95% home range: 281.88 ± 91 km2 and 50% core area: 6.6 ± 2.28 km2 (range 4.7–8.5 km2). We, therefore, consider the establishment phase of the re-introduction of Griffon Vulture in this particular site as successfully completed, but management should continue. Furthermore, the area of the Eastern Balkan Mountains can currently be regarded as a "source" for the species within the source-sink population regulation concept in the national and Balkan context.

Diversity of long-legged flies (Diptera, Dolichopodidae) of the Balkan Mountains (Bulgaria and Serbia)

The present paper gives information about 61 dolichopodid species distributed in the Balkan Mountains, Bulgaria and Serbia. Twenty-two species, collected from 13 localities, are new to the Balkan Mountains and seven of them (Dolichopus longicornis, Hercostomus chetifer, Medetera pallipes, M. muralis, Neurigona quadrifasciata, N. pallida and Sciapus costea) are new to the fauna of Bulgaria. Medetera pallipes and Sciapus costea are also new to the Balkan Peninsula. Thus, the total number of known species of the family Dolichopodidae for Bulgaria increases to 204.

Inoceramid bivalve and dinoflagellate cyst integrated biostratigraphy of the topmost Campanian–Maastrichtian in a part of the Western Fore-Balkan Mountains, northwest Bulgaria

We present the inoceramid and dinoflagellate cyst record from the topmost Campanian–Maastrichtian strata of three key sections of the Western Fore-Balkan Mountains, northwest Bulgaria. The following inoceramid zones were recognized: “Inoceramus” redbirdensis Zone, Endocostea typica Zone, Trochoceramus radiosus Zone and “Inoceramus” ianjonaensis Zone. The Campanian/Maastrichtian boundary was tentatively drawn slightly below the first occurrence of Endocostea typica. The uppermost inoceramid assemblage was confined to the lower part of the upper Maastrichtian. Dinoflagellate cyst ranges, as well as the first and the last occurrence events of dinocysts, provided valuable markers for the stratigraphic subdivision of the Maastrichtian. The first occurrence of Microdinium carpentierae was documented in proximity to the Campanian/Maastrichtian boundary. The Cerodinium diebelii Zone was recognized with a stratigraphical range from the lower Maastrichtian to the lower upper Maastrichtian. The last occurrence of Alterbidinium acutulum was recorded in the lower Maastrichtian and used as aid for tracing the lower/upper Maastrichtian substage boundary. The marked domination of delicate chorate dinocysts in all sections and the encountered low P/G ratio values are indicative of stable low-energy depositional environment and oligotrophic conditions, with normal marine productivity and nutrient availability in the basin during the Maastrichtian.

THE SOILS OF BOTEVGRAD VALLEY

The paper deals with Botegrad valley soil cover, properties, conditions and vegetation. The soil cover in the Botevgrad region is characterized by considerable diversity in the ravine valleys of the Bebresh River and its tributaries. Alluvial and Diluvial soils occur in the middle of the region in lowest parts. Gray forest soils developed in the Pre-Balkans and the northern slopes of the Balkan Mountains and Light Gray forest soils (Pseudopozolic soils) are spread there too. The most fertile soils are Dark gray forest soils but only in limited area. Shallow soils (Lithosols), are widely spread over reddish-brown quaternary materials, characterized by the presence of many skeletal particles. The soil cover on the slopes is eroded, cut by deep ditches, ravines and valleys. Main part of the land in the valley is cultivated. Arable lands for cultivation and pastures are about 68.4%, other 22% are used for mainly for forestry. Settlements, industrial zones and other infrastructure occupy 9% of the valley.