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Here we provide the first chironomid record and associated summer air-temperature (TVII) reconstruction between ca. 16,800–9100 cal yr BP from Lake Saint Anne (SZA), situated in the Eastern Carpathians. SZA was formed by the youngest volcanic eruption of Ciomadul volcano at ca. 29,600 cal yr BP. Our main goals in this study are to test whether warming after Heinrich event 1 (H1; ca. 16,200 cal yr BP) had similar amplitude to the late glacial warming, while Younger Dryas (YD) summers remained relatively warm in this region of Europe. We found the most remarkable chironomid assemblage change with a TVII increase of ~3.5–3.8°C at ca. 16,350 cal yr BP at SZA, followed by another slight TVII increase of ~0.8–1.0°C at ca. 14,450 cal yr BP. Only very minor temperature variations were recorded between 14,450 cal yr BP and 11,700 cal yr BP, with an unexpected TVII decrease in the Early Holocene. Variations in water depth together with increasing analogue problems and paludification from ca. 14,200 cal yr BP onwards may have influenced the reliability of our paleotemperature record obtained from SZA. In addition, Sphagnum-indicated decreasing pH, and hence decreasing nutrient level, likely overrode the effect of summer air-temperature changes during the Early Holocene, and this may explain the bias in the chironomid-inferred summer air-temperature reconstruction in the Early Holocene section.

How genetic diversity of populations reacts to neutral or adaptive processes such as population bottlenecks, immigration or local adaptation are central questions of population genetics. They may be directly answered through ancient DNA analysis, however such studies in plants are remarkably scarce, owing to the difficulty of gaining population-scale samples with good DNA preservation. Plant macrofossils are abundant in lake sediments, and here we assessed if they can be valuable material for population genetic studies. We extracted ancient DNA from early to late Holocene seed and needle remains of Norway spruce (Picea abies L. Karst) recovered from the sediment of a lake in the Retezat Mts. (South Carpathians). We aimed to reveal whether deforestations starting in the late Holocene and reaching maximum in the 19th and early 20th centuries have caused decreased genetic diversity in the modern Norway spruce population of the Retezat Mts. In a combined approach, we sequenced two plastid regions and generated detailed paleobotanical data to reconstruct the population history of Norway spruce. Our results show that genotyping success of the ancient material was high in samples younger than c. 2000-year-old, but was very low in early Holocene samples, and needles allowed genotyping with higher success compared to seeds. We discovered macrofossil samples that contained DNA from more than a single Norway spruce individual. This phenomenon, together with the possible multiple sampling of the same individual needs to be kept in mind when interpreting the genetic data obtained from macrofossils. Our results overall indicate a genetic diversity decrease during the late Holocene. We demonstrate that macrofossils preserved in sediments are invaluable material for population genetic studies.

This paper focuses on the Late Glacial (LG) and Holocene regional and local establishment times of several tree and shrub species in the Retezat Mountains (South Carpathians) using pollen, stomata and plant macrofossil records from four lakes situated at different altitudes. We used the empirical and rational pollen percentage limits to infer the local presence and population expansion/recession times. Our results show that Pinus mugo and P. sylvestris spread first at 15,100 cal yr BP in the mountain. P. mugo arrived at high altitudes (1740 m) already at 13,600 cal yr BP. The expansion of Larix decidua was weakly recorded in the pollen diagrams, but the plant macrofossil and stomata records suggested its Late Glacial expansion mainly on the northern slope and local presence since 14,900 cal yr BP at 1740 m. The species likely went extinct in the Late Holocene (around 3330 cal yr BP). The expansion of Picea abies and Ulmus commenced earlier on the southern slope, from 15,200 to 14,400 cal yr BP respectively, compared to the northern slope, where these species expanded from 14,300 to 13,850 cal yr BP. The following step was the expansion of Quercus at 13,900 cal yr BP. Following the Younger Dryas decrease of temperate deciduous taxa and P. abies, their expansion on the northern flank was in the order of P. abies (11,750), Ulmus (11,600), Quercus (11,100), Corylus (10,600), Carpinus betulus (7100), Abies alba (5100) and Fagus sylvatica (5000 cal yr BP). Timing of the Early Holocene tree expansions on the southern flank is ambiguous due to uncertainties in the Early Holocene age-depth model of Lake Lia; however, the mid-Holocene expansion of C. betulus and A. alba were well-dated in both southern slope pollen records to 7700 and 6100 cal yr BP, respectively, and we inferred several hundred years earlier expansion on the southern flank that can be explained by climatic differences. Higher solar radiation results in longer growing seasons and milder winters on the southern flank, which likely facilitated the earlier spread of these trees. For several woody taxa studied in this paper, last glacial maximum refugial populations can be inferred either locally in the mountain (P. abies, P. mugo, P. sylvestris, L. decidua) or in the region (Quercus, Ulmus, C. betulus, F. sylvatica) on the basis of their pollen presence since at least 15,700–16,000 cal yr BP and early increase during the LG. We compared the pollen inferred population expansion times of several tree taxa along a south-north transect in the Romanian Carpathians, and found that the Early Holocene high altitude expansion of A. alba (10,650–9400 cal yr BP) is exceptional in the region. We also demonstrated that the Holocene mass expansion of Quercus and C. avellana started earliest in the Retezat, and at least two centuries later in other sites in the Romanian Carpathians. We also demonstrated that certain tree species had preference for survival and/or early expansion on the northern slopes (A. alba, L. decidua, F. sylvatica), while others on the southern slopes (C. avellana, C. betulus).

International audience; We present the reconstruction of mire vegetation changes and fire history recorded in a continuous sediment profile that spans the last 20,000 cal yr BP from the Late Pleniglacial to Holocene in North-eastern Hungary. We also aimed to reveal past climate changes by using ecological requirements of specific aquatic plants as summer temperature indicators. Our results suggest the formation of a mesotrophic mire around 20,000 cal yr BP with brown moss, Betula sp. and Selaginella selaginoides cover beside the occurrence of Phragmites australis, Typha latifolia and T. angustifolia suggesting base-rich fen and tundra-like wet-ground habitats on the lakeshore. This community shifted to reed dominated swamp at c. 18,300 cal yr BP with inferred min. July temperatures of 12–15.7°C. Pinus sp., Betula nana, B. pendula/pubescens, Hippuris vulgaris and P. australis dominated until 16,600 cal yr BP pointing to shallow muddy stagnant water and colder climatic conditions than in the preceding interval. The most warmth-demanding species, T. latifolia and T. angustifolia indicated July mean temperatures > 14-15.7°C soon after the LGM. The formation of biogenic carbonate also started at an early stage; major accumulation occurred between 15,200 and 10,000 cal yr BP. In the Early Holocene, environmental indicator species (e.g. Phragmites australis and T. latifolia) pointed to warmer and shallower conditions, while the late Holocene was characterised by strong eutrophication and reed swamp dominance on the lakeshore. Elevated macrocharcoal concentration, wood fragments and remains of Typha species suggested frequent local fires and dry mire surface conditions during the last 1700 years.

As demonstrated by an increasing number of palaeoclimatic and palaeoecological studies, rapid climate change events (RCCs) occurred frequently in the Holocene and their timing correlates well in the European records. Changes in vegetation composition and environmental conditions were significant during these RCC events. In this study we use high resolution pollen, stomata, micro- and macrocharcoal, macrofossil, siliceous algae, biogenic silica and organic content analyses from two alpine lake sediments (Lake Brazi, 1740 m a.s.l.; Lake Gales, 1990 m a.s.l.) in the Retezat Mts, South Carpathian Mountains, Romania. Our aim is to study ecosystem responses to RCCs between 12,000 and 7000 cal yr BP using high-resolution proxy analyses of the relevant sediment sections. We detected several significant changes in the terrestrial vegetation composition and aquatic ecosystems in case of both lakes. Complex ecosystem responses were found in connection with the early Holocene RCC intervals. Most prominently, the 10.2 ka climatic change likely fostered the extinction of Larix decidua from the shore of Lake Brazi, while climatic change during the 8.2 ka event facilitated the establishment of Carpinus betulus in the lower deciduous mixed oak forests, due to decreasing growing season temperatures, frequent summer droughts and associated recurrent fire events. Taken together, most of the significant pollen compositional changes reflected the periodic spread of pioneer deciduous tree taxa (mainly Fraxinus excelsior and Corylus avellana) during the early Holocene RCCs. In all cases, this change was connectable to increased regional fire activity and the temporary increase of herbs. The most significant change in the lake-ecosystems was often the short-lived spread of various planktonic diatom species, mainly the members of genus Aulacoseira. Sudden appearance and large-scale percentage increase of these taxa suggested higher water-depth and/or intensified water turbulence.

To investigate treeline and timberline dynamics in the Retezat Mountains (Romanian Carpathians), late glacial and Holocene sediment sequences from four lakes were studied. The south and north slopes of the mountain range were compared using two lakes from the north flank (Lake Brazi, 1740 m a.s.l. and Lake Gales, 1990 m a.s.l) and two from the south flank (Lake Lia, 1910 m a.s.l. and Lake Bucura, 2040 m a.s.l.). Macrofossil and stomata analyses were performed to assess changes in the local vegetation, supplemented by pollen, charcoal and loss-on-ignition analyses. Our results show that treeline reached Lake Brazi on the northern side during the late glacial (ca. 14,000 cal yr BP) and then Lake Gales between 11,000 and 10,800 cal yr BP. During the early Holocene the upper limit of closed forest, the timberline, reached and passed Lake Brazi and has stayed above it since, but it has never reached Lake Gales at 1990 m a.s.l. The expansion of Larix decidua in the late glacialand early Holocene around Lake Brazi is unique. Stomata and macrofossils of Abies alba are also more abundant in the northern records. On the southern flank, treeline reached Lake Lia at around 12,000 cal yr BP, and was either very close to or at the elevation of Lake Bucura between ca. 8600 and 3000 cal yr BP. Timberline reached Lake Lia at ca. 8000 cal yr BP, some 3000 years after Lake Brazi, only 170 m lower on the north slope. Local fire events delayed the advance of timberline around Lake Lia in the early Holocene in a dry continental climate. The surrounding forest was dominated by Picea abies with individuals of Pinus cembra and stands of P. mugo until about 3000 cal yr BP when timberline retreated below the lake. Maximum elevation of timberline was attained between ca. 8000 and 3000 cal yr BP, after which it descended in response to climate cooling. Regional climate change appears to be the main driver of treeline dynamics, but it was modified by local climatic differences due to slope aspect. The first signs of human disturbance appeared ca. 4200 cal yr BP, when naturally open areas were used as alpine pastures. Human impact in the treeline ecotone, mainly burning and grazing, was intensified after ca. 2600 cal yr BP, contributing to the widening of the ecotone and the lowering of the timberline.

Two high-altitude lake-sediment sequences (Lake Lia, 1910 m a.s.l. and Lake Bucura, 2040 m a.s.l.) from the Retezat Mountains (South Carpathians, Romania) were analysed using multi-proxy methods to study responses of treeline, timberline and alpine/subalpine vegetation to climate change and human impact during the past 16,000 years. Woody species ( Pinus mugo, Pinus cembra, Picea abies and Juniperus communis) reached Lake Lia between 12,000 and 11,800 cal. yr BP, whereas P. mugo colonised the shores of Lake Bucura at 9600 cal. yr BP. Lake Lia was in the timberline ecotone between 8000 and 3200 cal. yr BP, in semi-open P. cembra and Picea abies woodland, probably mixed with P. mugo on the steeper slopes. Lake Bucura was surrounded by the upper part of the krummholz zone during the mid-Holocene. The increase in P. cembra after c. 6000 cal. yr BP around Lake Lia suggests that the composition of the timberline forest changed. The disappearance of P. cembra and Picea abies around Lake Lia at ~3000 cal. yr BP reflects descent of the timberline. A large mean July temperature decline between 3300 and 2800 cal. yr BP may have driven or at least contributed to the descent of the Picea abies–P. cembra forests. An increase in human indicator pollen types in Lake Bucura around 4200 cal. yr BP may reflect human impact in the naturally open alpine zone in the Late Bronze Age. In contrast, human impact likely appeared considerably later, around 2650 cal. yr BP (Early Iron Age) around Lake Lia in the upper subalpine zone. Human impact likely intensified after 2200 cal. yr BP at both sites that resulted in the lowering of the krummholz zone. We conclude that climate change and human impact both played an important role in the lowering of the treeline and timberline in the late-Holocene.

In this paper, we present high-resolution early Holocene pollen, plant macrofossil, charcoal, diatom, biogenic silica, and loss-on-ignition records from a mountain lake in the South Carpathians in order to reveal ecosystem response to the 8.2-ka climatic oscillation. We found significant changes both in terrestrial vegetation and lake diatom assemblages in the northern slope of the Retezat Mts between c. 8300 and 8000 cal. yr BP. Rapid changes in relative frequencies and pollen accumulation rates of the major deciduous pollen types associated with peaks in microcharcoal accumulation rates suggested that vegetation disturbance mainly took place in the mixed-deciduous forest zone, where woodland fires partially destroyed the populations of Fraxinus excelsior, Quercus, and Corylus avellana and facilitated the establishment of Carpinus betulus in the forest openings. The diatom record furthermore showed the spread of a planktonic diatom species, Aulacoseira valida, at 8150 cal. yr BP, coincidently with a short-lived expansion of C. betulus. Since diatom blooms mainly occur in spring in the Retezat Mts, increased spring water depth and increased water turbulence were inferred from these data. The expansion of C. betulus against F. excelsior and C. avellana at the same time suggested a modest increase in available moisture during the growing season. Taken together, these data imply that during the 8.2-ka event, winter and spring season available moisture increased, while summers were characterized by alternating moist/cool and dry/warm conditions.

Eugen von Gothard (1857–1909) made significant contributions to astrophysics and founded the Astrophysical Observatory in Hereny, Hungary, in 1881. He also was a gifted instrument maker who designed and produced the apparatus and equipment he needed to carry out his researches, which enabled him to respond immediately to Wilhelm Conrad Rontgen’s astonishing discovery of X rays. Von Gothard took his first X-ray photograph on January 23, 1896, thus inaugurating his first series of experiments, which ended on May 26, 1896. He carried out a second series of experiments on June 21–22, 1905, four years before his premature death at age 51.

A tungiasis a homoki bolhának – Tunga penetrans (Linnaeus, 1758) – a gazda bőrébe behatoló nősténye által okozott bőrbetegség. Esetismertetés : 39 éves férfi beteg 2005 májusában jelentkezett vizsgálatra a bal láb I. ujján kialakult elváltozás miatt a Szent Rókus Kórház Bőr- és Nemibeteg Gondozójában (Budapest). A lábon jelentkező elváltozás keletkezésekor Brazíliában, a tengerparton tartózkodott, ahol gyakran sétált mezítláb a homokban. Ott-tartózkodása 6–7. napján, a bal láb I. ujján, kb. 6–7 mm átmérőjű, szélén vizenyős, középen barna pontozottságot mutató elváltozást észlelt. Vizsgálatkor a bal láb I. ujjának mediális felszínén 6 mm átmérőjű, kiemelkedő, klinikailag pustulának tűnő elváltozás volt látható, kb. 2 mm-es hyperaemiás szegéllyel. Az elváltozás megnyitásakor határozott nyomásra kb. 4 mm átmérőjű fehéres színű, nem feszes falú tok buggyant elő. A féreggyanús képletet az Országos Epidemiológiai Központ Parazitológiai Osztályán (Budapest) Tunga penetrans ként azonosították. Következtetés: Esetismertetésünkkel a hazai szakemberek figyelmét kívánjuk felhívni erre a Magyarországra is behurcolható egzotikus betegségre. Tudomásunk szerint ez Magyarországon az első diagnosztizált behurcolt humán tungiasis eset.