Pirin Mountains Research Articles

Xiphinema pirinense n. sp. (Nematoda: Dorylaimida: Longidoridae), a new species from Bulgaria with a digitate tail

A description of Xipinema pirinense n. sp. is provided. This is a parthenogenetic nematode found associated with Fragaria sp. and Alchemilla sp. (Rosaceae) close to pine trees in the Pirin Mountains, Bulgaria. The species is characterised by its medium body length (3.2-3.9 mm), rounded head region slightly demarcated by a shallow depression, long odontostyle (116-134.5 microm), tripartite uterus with a Z-differentiation consisting of 4-7 irregular moderately refractive bodies with a clear central part, and a digitate tail with a ventral peg. The new species is most similar to X. index Thorne & Allen, 1950 and X. diversicaudatum (Micoletzky, 1927) Thorne, 1939.

Starting a programme for research and monitoring of sediment transfer processes in the periglacial zone of Bulgaria (Bulgarian Periglacial Programme)

The Bulgarian Periglacial Programme is organized by the Institute of Geography of Bulgarian Academy of Sciences. It aims to investigate and observe contemporary geomorphic processes that occur in the Bulgarian periglacial zone located in the alpine and subalpine parts of the Rila and Pirin Mountains at altitudes of 2200–2925 m a.s.l.). The research will be used to create a set of landscape models, which to be used for assessment environmental reactions to global change and for environmental hazards risk assessment. Realization of the programme is of considerable importance for the Institute and for Bulgarian science as a whole and this type of research is currently lacking in the Bulgarian periglacial environment. The programme should be performed in close collaboration with European and global scientific community, with application of up-to-date standardized methods which to allow comparison with results from studies conducted elsewhere in the world. In essence, the Bulgarian Periglacial Programme is not a project – it is much more a strategic line, which should generate series of project proposals that will ensure the fulfilment of all the tasks planned. Hence, the main goal of the programme is to ensure an international partnership on wide basis.

Preliminary mapping and characterisation of soils in the Pirin Mountains (Bulgaria)

Soil types, humus types and vegetation as well as their hypsometric variation were analysed in terms of sequences in the northern part of the high mountains of the Pirin National Park at altitudes between 1000 and 2400 m a.s.l. The study area is characterised by a large variety of natural parameters like petrology (mainly marble and granite), morphology (different slope deposits, exposition) and the orographic climate gradient. Statistical analyses using these parameters provided a basis for the soil group classification of the sites. Based on a Digital Terrain Model (DTM) and a geological map of the Pirin National Park, the results of these statistical analyses were used to generate a "map of potential soil groups" (regionalisation using GIS). Six potential soil groups could be determined. The resulting map exhibits a confidence level of 68 % on 74.4 % of the covered area. Rendzic Leptosols, in combination with Folic Histosols and Histi-lithic Leptosols occur in the alpine and subalpine regions on calcareous substrates. With decreasing altitude they are replaced by a mosaic of Rendzic Leptosols, Phaeozems and an increasing occurrence of Cambic Umbrisols. Umbrisols found on silicatic substrates in the alpine region are replaced by Cambic Umbrisols with decreasing altitude as well. Hence, pedogenesis is characterised by increasing browning and depth of the soil profiles with decreasing altitude. The pH-level is slightly acidic to neutral in lower zones and on calcareous rocky bases. Acidification increases in the subalpine zone. Soil pH decreases down to 4 on silicate subtrates. Typical humic values in mineral topsoils are 10 to 12 %, and in organic layers of the soils above 2000 m a.s.l. they are even more. The C:N ratio closely ranges around 20 (median).

Data to the leaf-beetle fauna of Macedonia (Coleoptera, Chrysomelidae)

Data to the leaf-beetle fauna of Macedonia. {Coleoptera, Chrysomelidae) - During the period of 1976-2004 the authors organized 10 collecting trips to localities in the areas of historical Macedonia (Republic of Macedonia, Pirin Mountains in Bulgaria and the Macedonian provinces of Greece). They have found 213 species of 61 genera in 11 subfamilies of Chrysomelidae. 23 species proved to be new to the fauna of the Republic of'Macedonia (ex Yugoslavian Macedonia).

Snow cover variability in Bulgarian mountainous regions, 1931–2000

AbstractPrincipal component (PC) analysis was carried out on annual snow cover series from 15 mountain climate stations in Bulgaria to characterize the spatial and temporal variability in snow cover over the 1931–2000 period. Three distinct snow cover response regions were identified: (1) high elevation sites above 1500 m in the Vitosha and Rila Mountains; (2) low elevation sites below 1000 m in the eastern Rhodope and southern Pirin Mountains and (3) a mid‐mountain zone of 1000–1500 m elevation including stations from several mountain ranges. Snow cover exhibited evidence of significant decadal‐scale variability over the 1931–2000 period but little evidence of long‐term trends linked to climate warming. Over the more recent 1971–2000 period, the mid‐mountain zone has increased in importance and shows a significant trend toward a later start to the snow cover season.Composite analysis of high and low snow accumulation winters showed high accumulation years associated with a negative North Atlantic Oscillation (NAO)/East Atlantic (EA)‐like pattern that favored increased winter precipitation over the Mediterranean and Balkans and anomalous easterly flow across the Black Sea into Bulgaria. Low snow accumulation years were associated with the positive mode of a Scandinavian (SCA)‐like pattern that generated fall warming, a delay to the start of the snow cover season and reduced winter precipitation. Correlation of annual snow cover series with these modes of atmospheric variability revealed few significant correlations but evidence of considerable secular variability in the strength and sign of the relationships. This reflects the complex climate regime of Bulgaria, which is located at the cross‐roads of Mediterranean and Continental climate influences and on the periphery of the main nodes of influence of Northern Hemisphere circulation patterns that play important roles in European snow cover variability. Copyright © 2007 Royal Meteorological Society

Chronological framework for the Lateglacial pollen and macrofossil sequence in the Pirin Mountains, Bulgaria: Lake Besbog and Lake Kremensko-5

The sediments of numerous cirque lakes in the Pirin Mountains have yielded several generalized pollen diagrams, but low stratigraphic and temporal resolution has hampered detailed reconstruction of the vegetational history, especially for the Lateglacial. New pollen and macrofossil analyses of high stratigraphic resolution combined with well-controlled timedepth curves for Lake Besbog and Lake Kremensko-5 now permit the firm identification of the Lateglacial interstadial interval (BollingAllerod), dated at 13.8 � 12.6 ka cal. BP at Besbog and 14.1 � 12.8 ka cal. BP at Kremensko-5 and correlated with the Greenland Interstadial GI-1 (14.5 � 12.6 ka cal. BP). Macrofossil analyses indicate that during the Bolling � Allerod period Betula and Juniperus occurred around the lakes (at 2124 � 2250 m a.s.l). Following the Younger Dryas a Betula woodland covered the mountains between 1900 and 2250 m in the early Holocene. Because of higher summer insolation at this time, the temperate deciduous forest reached up to 1900 m, or 800 m above their present limit, producing a regional pollen rain that dominated pollen deposition in the cirque lakes. After about 7000 cal. yr BP conifer forests replaced the birch woodland at middle and high elevations.

Elevational gradients during the Late-Glacial/Holocene vegetational transition in southern Bulgaria

The Late Glacial and early-Holocene vegetational history of a newly dated pollen and macrofossil diagram from Besbog, a cirque lake at 2250 m just above the forest limit in the Pirin Mountains of southwestern Bulgaria, is compared with a newly dated pollen diagram for the mire Shiroka Polyana at 1400 m in the conifer forest of the nearby Rhodope Mountains in order to investigate the chronology of major changes in the vegetation at different elevations. In the Lake Besbog record the non-arboreal pollen assemblage of the Late Glacial changed abruptly to that of Betula, Quercus and other deciduous types. The date for this change is about 11.6 ka cal b.p. The Quercus assemblage may be composed of pollen blown from intermediate elevations, to which deciduous forest had expanded because of higher summer temperatures related to high summer insolation. At Shiroka Polyana (1400 m) in the modern conifer belt, a similar change did not occur until about 8.8 ka cal b.p. The persistence of the dry steppe or steppe forest in the early Holocene at this lower site can also be attributed to high summer insolation. Thus as atmospheric temperature increased at the end of the Late Glacial, deciduous forests expanded first at intermediate elevations in the Pirin Mountains and only later in the Rhodope Mountains at lower elevations as summer insolation decreased.

Structure of Pinus sylvestris L. populations in Bulgaria revealed by chloroplast microsatellites and terpenes analysis: Provenance tests

In the present study we investigated the genetic structure and genetic diversity of Pinus sylvestris populations in Bulgaria using chloroplast microsatellite markers and terpene analysis. We were interested in addressing the following questions: (1) can population structure in Scots pine be detected via chloroplast microsatellites markers and terpenes; (2) are there differences in population differentiation between the two analyses; and (3) how are the patterns related to geographic distances. Twelve provenances were chosen throughout the species' range in Bulgaria. Following DNA extraction, chloroplast microsatellite (cpSSR) loci were surveyed using six primer pairs. Between 4 to 8 size variants were identified at each locus. A total of 35 size variants at the six loci were identified, 11 occurring at low frequencies (<1%). They were combined in 134 different haplotypes, of which seven represent 1/3 of the genetic structure. AMOVA analysis revealed that 10.99% of the variation was found among populations, while 89.01% was expressed within populations. The cpSSR analysis divided Scots pine populations into two groups, the first represented by populations located in the south-western part of the Rhodopes and Pirin mountains, while the second group is located in the northeast of Rhodopes and Rila mountains. Terpene analysis revealed that on average, 53% of the monoterpene pool in P. sylvestris was accounted for by α-pinene (range 47–59%) followed by β-pinene (range 6–12%). The presence of two distinct groups is weekly consistent with physical distances between populations, similar significant correlation between genetic distance determined by chloroplast microsatellites analysis and chemotype distance (determined by terpenes) was observed. Our results suggest that the structural pattern of genetic diversity of cpDNA in Scots pine populations is the consequence of historical biogeographic processes.

Dissimilar patterns of Pinus heldreichii Christ. populations in Bulgaria revealed by chloroplast microsatellites and terpenes analysis

In the present study we investigated the genetic structure and genetic diversity of Pinus heldreichii populations in Bulgaria using chloroplast microsatellite markers and terpene analysis. We were interested in addressing the following questions: (1) can population structuring in Bosnian pine be detected via chloroplast microsatellite markers; (2) are there differences in population differentiation as determined by terpenes and microsatellites; and (3) how are the patterns of size variant frequencies and geographical distances related. Four provenances were chosen throughout the species' range in Bulgaria. Following DNA extraction, chloroplast microsatellite (cpSSR) loci were surveyed using 6 primer pairs. Between 2 and 5 size variants were identified at each locus. A total of 16 size variants at the 6 loci were identified, 4 occurring at low frequencies. They were combined in 21 different haplotypes including 11 that were unique. AMOVA analysis revealed that 18.25% of the variation was found among populations, while 81.75% was expressed within populations. The cpSSR analysis divided Bosnian pine populations into two groups, the first represented by populations B, C and D located in the south and north-western part of the Pirin and Slavianka mountains, while the second group, represented by population A, is located in the north-eastern Pirin mountain. Terpene analysis revealed that on average, 59% of the monoterpene pool in P. heldreichii is accounted for by limonene (range 36–48%) followed by α-pinene (range 16–17%). The presence of two distinct groups (Pop-A, Pop-D and Pop-B, Pop-C) is more consistent with physical distances between populations. No significant correlation between genetic distance determined by chloroplast microsatellites analysis and chemotype distance determined by terpenes was observed. Our results suggest that the structural pattern of genetic diversity of cpDNA in Bosnian pine populations is the consequence of historical and biogeographical processes.

A note on the scorpions from the Pirin Mountains, southwestern Bulgaria (Scorpiones: Buthidae, Euscorpiidae)

In the present note, four scorpion species are recorded from the Pirin Mountains in southwestern Bulgaria, including the first records for Bulgaria of both Mesobuthus gibbosus (Brullé, 1832) (Buthidae) and the “mingrelicus complex” of the genus Euscorpius Thorell, 1876 (Euscorpiidae) (the latter based upon an undetermined species). Also, E. hadzii Caporiacco, 1950 and another undetermined species of Euscorpius belonging to the “carpathicus complex” are recorded from Pirin. The taxonomic affinities of the taxa are discussed, as well as some biogeographical considerations about the scorpions of this poorly studied mountainous area.

Late-glacial vegetational history of Lake Kremensko-5 in the northern Pirin Mountains, southwestern Bulgaria

The core of Lake Kremensko-5, one of the cirque lakes in the northern Pirin Mountains of southwestern Bulgaria, contains sediments from more than 13,500 years b.p. and a pollen stratigraphy that can be correlated with the interstadial/stadial cycle of the Late-glacial period. Artemisia and Chenopodiaceae predominate in the basal part of the sequence, indicating the presence of mountain steppe type vegetation soon after the ice retreat. A sharp increase of Pinus diploxylon-type and Poaceae after 12,360 b.p. is followed by a return of Artemisia and Chenopodiaceae, marking the Younger Dryas. Its abrupt termination must result from an unconformity, for high values of Quercetum mixtum, dated at other sites in the Pirin Mountains as early Holocene, are missing here, perhaps because of erosion at a time of low lake level related to the high insolation maximum during the early Holocene.

Holocene palaeovegetation of the Northwestern Pirin Mountains (Bulgaria) as reconstructed from pollen analysis

Pollen analysis and radiocarbon dating were performed on a sequence 150 cm deep from a peat bog (Mozgovitsa, 1800 m above sea-level) in the Northwestern Pirin Mountains, Bulgaria. The palaeovegetational reconstruction focused on the main stages of forest development starting from approximately 8700 years BP. The vegetational response to the amelioration of the climate in the Early Holocene until 7500 cal BP resulted in the spread of birch forests ( Betula pendula) that occupied large areas at high altitudes forming the upper tree-line together with pine ( Pinus sylvestris, Pinus peuce, Pinus mugo), juniper ( Juniperus), alder ( Alnus), and willow ( Salix). Below them were mixed deciduous oak forests with some Ulmus, Tilia, Corylus, Carpinus, and Acer. The continuous Early Holocene pollen record of mesophyllous demanding trees ( Abies alba, Fagus sylvatica and Picea abies), though in low frequencies, suggests that groups of these trees survived in environmentally favourable habitats with sufficient moisture such as deep mountain valleys. The most important change in the vegetation cover started ca. 7500 cal BP when birch forests declined and coniferous vegetation dominated by Pinus sylvestris, Pinus peuce and Abies alba invaded the slopes. The spread of the conifers and the expansion of their areas presume an increase in humidity and precipitation, and the development of soils with humic horizons. The last trees to establish after ca. 4000 cal BP in the study area were Picea abies and Fagus sylvatica. Their expansion in the Northwestern Pirin Mountains started at the Subboreal/Subatlantic transition ca. 3000 cal BP when average temperatures dropped and precipitation increased. Deforestation in historic times resulted in the appearance of new pasture land and the lowering of the upper tree-line.

Lateglacial and Holocene vegetation belts in the Pirin Mountains (southwestern Bulgaria)

Pollen stratigraphy of a core 270 cm long from Lake Dalgoto at 2310 m in the Northern Pirin Mountains, southern Bulgaria, was treated by optimal partitioning and compared to a broken-stick model to reveal statistically significant pollen zones. The vegetational reconstructions presented here are based on pollen percentages and pollen influx, on comparisons of modern and fossil pollen spectra, and on macrofossil dates from other sites in the mountains. During the Younger Dryas (11000–10200 14C yr BP), an open xerophytic herb vegetation with Artemisia and Chenopodiaceae was widely developed around the lake. Deciduous trees growing at lower elevations contributed to the pollen rain deposited at the higher-elevation sampling sites. Specifically, from 10200 to 8500 yr BP, Quercus, Ulmus, Tilia and Betula expanded rapidly at low and intermediate elevations, and between 8500 and 6500 yr BP they extended to higher elevations close to the upper forest limit, which was formed by Betula pendula at about 1900 m. Coniferous species were limited in the region at this time. After 6500 yr BP, the expansion of conifers (Pinus peuce, P. sylvestris, P. mugo, Abies alba) at high elevations forced the deciduous trees downward. Between 6500 and 3000 yr BP, the forest limit at 2200 m was formed by P. peuce, and A. alba had its maximum vertical range up to 1900 m. Later the abundance and vertical range of P. peuce and A. alba were reduced. After 3000 yr BP, Picea expanded.

The Holocene vegetation history of Northern Pirin Mountain, southwestern Bulgaria: pollen analysis and radiocarbon dating of a core from Lake Ribno Ban derishko

Pollen analysis was performed on a 343 cm long core recovered from Lake Ribno Banderishko (2190 m) on Northern Pirin Mountain (southwestern Bulgaria), supplemented by six '4C AMS dates. The lower part of the sequence (343-290 cm) was deposited during the Lateglacial when mountain-steppe vegetation with Artemnisia, Poaceae, Chenopodiaceae and other herbs, and with stands of Pinus and Juniperus, dominated at high altitudes. The identification of pollen of mesophilous trees suggests that local populations may have survived in refuges below 1000 m where environmental conditions were favourable for their growth. The reforestation dynamics in early-Holocene times (11200-8400 cal. BP) started with Betula forests at high altitudes and deciduous forests with Quercus, Ulmus, Tilia and Fraxinus excelsior at lower altitudes. The time of the maximal spread of Corylus at c. 8000 cal. BP coincided with the establishment of Abies alba in the forests, and the beginning of the formation of a coniferous belt, dominated by pines (Pinus sylvestris, P. peuce, P. nigra and P. heldreichii). The late immigrants Fagus sylvatica and Picea abies invaded the mountain slopes at c. 4400 cal. BP and 3300 cal. BP, respectively. Palynological traces of anthropogenic activity and landscape management began after c. 2200 cal. BP.

Granitoid magmatism in the Pirin Mountain - magma generation, emplacement and exhumation of the Central Pirin pluton

Granitoid magmatism in the Pirin Mountain - magma generation, emplacement and exhumation of the Central Pirin pluton

Epilithic cyanophytes from soft-water mountain lakes in the Central Alps (Austria) and in the Pirin Mountains (Bulgaria) with special reference to taxonomy and vertical zonation

Epilithic cyanophytes from soft-water mountain lakes in the Central Alps (Austria) and in the Pirin Mountains (Bulgaria) with special reference to taxonomy and vertical zonation

Medioppia centrodentata sp. n. (Acarina, Oribatei, Oppiidae) from Bulgaria

&lt;i&gt;Medioppia centrodentata&lt;/i&gt; sp. n. is described from the Pirin mountains, Bulgaria. It differs from the other species of &lt;i&gt;Medioppia&lt;/i&gt; in the form and size of the medial tooth on the rostrum, the form of the tubercles and bothridia, the central base of the prodorsum and the hairs on epimeron IV.

Первые находки микрофитофоссилей в мраморах Добростанской свиты в Северном и Южном Пирине

Preliminary results of the studies on 12 samples from Dobrostan Formation along three profiles in Northern and Southern Pirin Mountain, as well as on one sample from the stratotype of the Formation in the Central Rhodope Mountains, revealed different amounts of organic matter. The latter consists of organic coats, plant detritus, graphite crystals and kerogene matter, and contains also specimens of microphytofossils in differing state of preservation. The following taxa have been determined: Protosphaeridium sp., Protosplweridium den sum Tim., Kildinella sp., Kildinella cf. sinica Tim., Kildinella cf. hyperboreica Tim., and Trachysphearidium (?) sp. These microphytofossils are characteristic for the Upper Proterozoic (Riphean). The presence of the genus Kildinella – a guide fossil for the Riphean of Eurasia, confirms the Riphean age of Dobrostan Formation in Pirin Mountain, i.e. the same age already establi shed for this Formation in its type region.