Ionuț Cornel Mirea

"Emil Racovita" Institute of Speleology | ERIS · Department of Geospeleology and Paleontology

The Ursilor Cave (NW Romania) is a famous cave bear paleontological site hosting an important Late Pleistocene faunal assemblage and subject to systematic excavation works. To better understand the origin of fossil assemblages, the sedimentary history of the cave must be reconstructed. We conducted a series of investigations on various cave deposit...

We present here the results of a four year environmental monitoring program at Ascunsă Cave, Romania, intended to understand how climate information is transferred through the karst system and archived in speleothems. The air temperature inside the cave is around 7 °C, with slight differences between the upper and lower parts of the 20 main passage...

Late Pleistocene European cave bears (Ursus spelaeus) have been considered to be largely vegetarian, although stable isotope data (δ13C and δ15N values) from the Romanian Carpathians has suggested considerable dietary variation. Here we evaluate previous and additional adult cave bear isotopic data from four Marine Isotope Stage 3 (MIS 3) sites in...

The palaeoichnology of the cave bear, Ursus spelaeus, was studied at Urşilor Cave, Apuseni Mountains, Romania, to acquire new data about the ethology and the metrics of this extinct species. Eight stations containing footprints, scratch marks and nests were surveyed using laser scanning to build tridimensional models for several cave bear nests, wa...

Caves often hold valuable palaeoclimate archives including speleothems, fossil remains, and clastic sediments that complement each other. This paper presents a multi-archive interdisciplinary study of an extensive deposit of fossil mammals from the scientific reserve in the Muierilor Cave, Southern Carpathians, Romania. We present two new palaeonto...

The response of European precipitation variability to climate change is still poorly understood. Here we present a high-resolution speleothem record of Eastern Central European (ECE) autumn/winter precipitation to study decadal to centennial hydroclimatic variations in the European-Atlantic sector since the Last Glacial Maximum. The Cloşani Cave δ¹...

Caves are well-known archives that preserve valuable information about the past, relevant for reconstructing past climates and environments. We sampled sediments from a 480 cm deep profile. 16S rRNA gene-based metabarcoding analyses were undertaken that complemented lithological logging, sedimentology, and Optically Stimulated Luminescence (OSL) da...

Caves are ideal environments for preserving quantifiable deformational indicators in orogenic areas, as they are conditioned by regional tectonics. The caves and karst of Isverna, developed in the Barremian-Aptian limestones of the Danubian sedimentary nappes (Southern Carpathians, SW Romania), expose formerly undetected evidence of compressional t...

A recent palaeontological excavation in Muierilor Cave, southern Carpathians (Romania), has recovered one of the largest populations of Late Pleistocene wolves (Canis lupus Linnaeus, 1758; MNI =25) documented in Eurasian cave deposits. Many individual nests with wolf bones, including fully articulated skeletons, were found in a remote passage of th...

Cave bears (Ursus spelaeus) have been recognized as being predominantly herbivorous. However, RomanianCarpathian cave bears have displayed a flexible diet based on a wide range of δ15N values. In this work, weanalyse 97 lower first molars of Ursus spelaeus and contemporaneous Ursus arctos from different sites in thisregion, using dental microwear a...

Beetles are ubiquitous cave invertebrates worldwide that adapted to scarce subterranean resources when they colonized caves. Here, we investigated the potential role of gut microbiota in the adaptation of beetles to caves from different climatic regions of the Carpathians. The beetles’ microbiota was host-specific, reflecting phylogenetic and nutri...

Moonmilk is a cave deposit that was used for medical and cosmetic purposes and has lately raised interest for its antimicrobial potential. We studied five moonmilk samples from four caves with different microclimatic conditions, two temperate in north-western and northern Romania (Ferice, Fața Apei, and Izvorul Tăușoarelor caves) and one tropical i...

Beetles are ubiquitous cave invertebrates worldwide that adapted to scarce subterranean resources when they colonized caves. Here, we investigated the potential role of gut microbiota in the adaptation of beetles to caves from different climatic regions of the Carpathians. The beetles microbiota was host-specific, reflecting phylogenetic and nutrit...

Natural and anthropogenic factors highly influence the concentration of major (Na, Mg, K, Ca) and trace (Sr, Ba, Mn, Li) elements, anions (HCO3−, NO3−, SO42−, Cl−), and Sr isotopic signatures. The current study identified the Sr isotopic signature in groundwaters from the Southern Carpathians and Apuseni Mountains karst areas of Romania and its rel...

Bat species inhabit subterranean environments (e.g., caves and mines) in small areas with specific microclimatic conditions, during various periods of their life cycle. Bats can be negatively influenced by microclimatic changes within their roosts if optimal habitat patches become unavailable. Therefore, proper management solutions must be applied...

Long-term monitoring reveals the temporal evolution of groundwater chemistry and the potential human health risk posed by the use of contaminated waters (Giri and Singh 2015). Groundwater aquifers are an important source of drinking water in Romania. This study was conducted to appraise the groundwater chemistry and the potential non-carcinogenic r...

Muierilor Cave is one of the most important caves in Romania from paleontological, biological, and archaeological points of view. A newly discovered chamber, with unique yellow calcite crystals, fine-grained crusts, and black sediments, is connected to the upper levels that contains fossil bones and a large pile of guano. Samples were taken from th...

Here we aimed at evaluating the diversity, abundance, and organic substrate preferences of microbial communities associated with sediments and water from a pristine karst cave located in Romania. Methods: Culture-independent techniques were employed to evaluate bacterial diversity, for which total environmental DNA (eDNA) was extracted using the Qu...

The current study was conducted to assess the level and spatial distribution of metal pollution in surface water, soil, and sediment samples from the Arieș River basin, located in central Romania, an area impacted by various mining and industrial operations. Several pollution indices, spatial distributions, cluster analyses, principal component ana...

In karst areas, anthropogenic contaminants reach the subsurface with detrimental effects on the groundwater ecosystem and downstream springs, which often serve as drinking water sources for the local human communities. We analyzed the water chemistry and microbial community composition in upstream and downstream locations of five hydrokarst systems...

Muierilor Cave is one of Romania’s most important show caves, with paleontological and archeological deposits. Recently, a new chamber was discovered in the cave, with unique yellow calcite crystals, fine-grained crusts, and black sediments. The deposits in this chamber were related to a leaking process from the upper level that contains fossil bon...

Over the last thousands of years, human impact led to significant changes in the landscape, with impacts on the environment and the functioning of the ecosystems. We assumed that even small human settlements developed around water bodies might have a substantial impact that surpasses the natural cycles of climate change in an area, especially linke...

About 50 species of cave-obligate Leptodirini (Leiodidae) beetles have been described so far in Romania, most of them populating caves in the Apuseni Mountains (north-western Romania) and the Southern Carpathians. In this contribution, we present the first molecular phylogeographic study of the two troglobiotic Pholeuon species from the Apuseni Mou...

The chemical quality of waters from eight karst springs from the Southern Carpathians and the health risk of small rural communities using these springs as a drinking water source were assessed. The results indicated that the spring waters in the studied area are chemically suitable to be used as drinking water and pose no health risks for adults a...

The area around the town of Mangalia in Southern Dobrogea (Romania) hosts a unique karst landscape represented mostly by large collapse dolines. Around one of these collapse dolines, named Obanul Mare, there is a peculiar morphology of hillocks that resemble the tropical labyrinth-cone karst but on a much-reduced scale. This peculiar relief was hyp...

In this study, we describe a sedimentary deposit situated above Ascunsă Cave (SW Romania) that should be in depositional connection with coeval stalagmites from the cave. We excavated a 2.5 m deep soil profile and took contiguous bulk samples every 5 cm. Soil samples were analyzed for clay mineralogy, grain size, chemical composition, magnetic susc...

This study aims to investigate the quality and vulnerability of surface water (Aries River catchment) in order to identify the impact of past mining activities. For this purpose, the pollution and water quality indices, Piper and Durov plots, as well vulnerability modeling maps were used. The obtained results indicate that the water samples were co...

Water stable isotope ratios (δ18O and δ2H) are ideal tracers in the hydrological cycle, providing information about air mass history, moisture sources, or underground flow. We present here the isotopic composition of precipitation and cave drip water on the south-facing side of the Buila–Vânturarița Massif (central South Carpathians). Precipitation...

Human activities and natural factors determine the hydrogeochemical characteristics of karst groundwaters and their use as drinking water. This study assesses the hydrogeochemical characteristics of 14 karst water sources in the Apuseni Mountains (NW Romania) and their potential use as drinking water sources. As shown by the Durov and by the Piper...

(1) Background: Show caves are unique natural attractions and touristic traffic can trigger their degradation within a short time. There are no universal solutions to counter the effects of the touristic impact upon the cave environment and both protection protocols and management plans have to be established on a case-by-case basis. (2) Methods: T...

In rural areas without centralized water supply systems, inhabitants often use groundwater of unknown quality as drinking water, without understanding the possible negative consequences on their health. Karstic spring waters from Dobrogea region in Romania were assessed for their potential to be used as drinking water source, according to their qua...

Introduction: Karstic springs are used worldwide by rural communities as sources of fresh water for humans and livestock. In Romania, one-third of the population has no direct access to a public water supply. The present study is part of a country-wide project to develop simple, quick and cheap methods for seasonal environmental and microbiological...

(1) Introduction: Karstic springs are used worldwide by rural communities as sources of fresh water for human use and livestock survival. In Romania, 1/3 of the population has no direct access to the public water supply. The present study is part of a country-wide project on developing simple, quick and cheap methods for seasonal environmental and...

Background: The increasing human impact in Romanian caves raises the urgency of publishing a correct database of the strictly-adapted cave fauna. Previous attempts at indexing cave fauna and classifying caves by using their fauna opened many questions regarding the use of an incomplete list of cave species and mixed lists of troglobionts/stygobion...

When calcite precipitates in caves, its carbon stable isotope signature can be modified by the CO2 outgassing gradient between drip water and cave atmosphere. This effect is modulated by the water residence time in the cave, from its emergence in the cave until the deposition of calcite. Moreover, CO2 solubility, calcite precipitation rate, and iso...

In Eastern Europe, wind energy production is currently promoted as an important source of renewable energy, yet in most cases without appropriate consideration of the negative impacts wind turbines (WT) may have on protected species such as bats. Here, we present first data on fatality rates, fatality factors and the likely origin of bats killed by...

The Carpathian island-type glaciokarst has a great potential of preserving signals of past environments, archived in cave deposits like speleothems and clastic infills. We present here the geomorphology and structural control of several relict alpine caves and the surrounding glaciated marble karst in the Făgăraș Mountains. Four truncated and parti...

Acest volum este o colecţie de studii interdisciplinare realizate în cadrul proiectului demonstrativ „Platformă digitală integrată pentru valorizarea peisajului cultural din Munţii Buzăului. Studiu de caz: cadrul natural şi monumentele istorice din zona Aluniş-Bozioru”, derulat în perioada ianuarie 2017 - iunie 2018. Principalul obiectiv al proie...

The aim of this study was to monitor factors affecting the microorganisms of water bodies in caves and apply the findings to improve their management. Four show-caves in Romania were sampled monthly to obtain an overview of the changes occurring in the fungal and bacterial communities of cave waters in relation to surface and underground impacts. T...

Limanu Cave is a network maze situated in the southern part of the Dobrogea Plateau (SE Romania), close to the Black Sea coast. It is hosted in Sarmatian (Kersonian) lumashelic and oolithic limestones, interbedded with marls. The total length of its passages is close to 3.5 km, and it preserves evidences of important human impact on its wall morpho...

The Făgăraș Mountains consisting mostly of impervious metamorphic rocks are an unlikely location for karst development. Yet, due to the occurrence of a series of marble stripes interbedded within the metamorphic rocks, several caves developed in two areas in the central part of the mountains: Piscu Negru (at ~1200 m) and Mușeteica-Râiosu (between ~...

Since both caves developed in similar geological and hydrogeological conditions, they are presented in this chapter side by side. Although very different in size, both caves are well-known for their wide diversity of speleothems. Cioaca cu Brebenei is an 85 m long cavity that hosts some of the largest and most spectacular helictites of the Romanian...

Air microbial pollution in touristic areas poses a risk for both the integrity of an ecosystem and human health. Microbiological monitoring together with environmental parameters monitoring allows for the assessment of the impacts and formulation of sound management decisions to protect humans and ecosystems. Four show caves from the Carpathian Mou...

Geoelectrical investigation of underground cavities has some specific challenges. The geometry of the cavity, its volume and depth, as well as the presence of the filling material (when is the case), are the dominant factors for a successful resistivity survey. Despite the theoretical approach which seems to be favorable for such applications, ther...

Carpathian Mountains were one of the main refuge areas during the climate changes of the Pleistocene and the Holocene in Europe and one of the richest regions in the world in subterranean (caves and associated habitats) endemic species. Nevertheless, the Carpathian Mountains subterranean fauna importance is underestimated especially due to disperse...

In many countries, caves can pose an economic interest for the authorities and stakeholders. The development of a show cave requires, apart from the conservation issues, to ensure the human safety by minimising the exposure to radon for cave personnel and visitors. Radon levels can vary widely from cave to cave, being directly correlated with diffe...

As part of a microclimate study at Ascunsă Cave, Romania, we used Gemini Tinytag Plus 2 data loggers to record cave air temperature variability. At one of the monitoring points we recognized the presence of semidiurnal cycles on the order of a few thousands of a degree Celsius that could be produced under the influence of the semidiurnal tidal comp...

A total of 456 Nyctalus noctula individuals were rescued from a flat during December 2016 by specialists and volunteers from the Wilderness Research and Conservation Association and Visul Luanei Foundation. In order to reduce the relocation stress, the animals were temporarily cared for at the L’ARC animal rescue centre in Bucharest, within a hiber...

We present here the results of a 4-year environmental monitoring program at Ascunsă Cave (southwestern Romania) designed to help us understand how climate information is transferred through the karst system and archived by speleothems. The air temperature inside the cave is around 7 ∘C, with slight differences between the upper and lower parts of t...

Passage morphology and well-preserved kinematic indicators in a limestone-mélange contact cave from the South Carpathians provide evidence of thrusting mechanisms that occurred during the Late Cretaceous nappe emplacement. Large-scale normal faults occurred during the Eocene to Oligocene orogen-parallel extension, were deformed during the Late Mioc...

Scarp retreat is a common natural process which drives the evolution of landscape in monoclinal or horizontally bedded structures. The NW-facing, retreating limestone slope of the Vânturarița-Buila Massif, a mountain ridge in the South Carpathians, is incised by steep dry valleys (SDVs), parallel to each other and perpendicular to the ridge crest....

In taphonomy, the study of carnivore modification of fossil bones and the analysis of their dispersion represent the best approach to assessing the extent of bone modification and displacement for a given bone assemblage. Here we analyze the excavated bone deposit from Urşilor Cave, a well-documented and fossil-rich Upper Pleistocene cave bear site...

High-alpine caves are currently in the spotlight of research as they are host to speleothems, key recorders of Quaternary environmental change. Based on modern survey and analytical techniques, we investigated the karst morphology of M3-R2 Cave, the highest alpine cave in the Romanian Carpathians. Spatial modeling in Compass has shown survey detail...

Muierilor and Urșilor Caves are two representative paleontological sites of Europe as they bear significant MIS 3 cave deposits including fossil remains, sediments and speleothems. Over the last few years, we have conducted a number of paleontological excavation campaigns on both caves aimed at understanding the taphonomic processes that occurred d...

Rodents are valuable taxons of the fossil fauna from the Pleistocene epoch in Europe. Given their chronological value, the small mammals (rodents, insectivores) play an important role in drawing up the biochronostratigrafic scheme of the continental deposits. Due to its specific features, small mammal paleontology can provide relevant information o...

During the paleontological excavation process, that was conducted in Muierilor Cave, (Galbenului Valley, Southern Carpathians), several samples were selected for ancient DNA (aDNA) extraction. The AMS 14C ages from the Muierilor paleontological excavation indicate ca. 30 – 43 ky BP. The selection criteria for samples were as follows: target species...

This study aims to identify bat migration patterns in the western Black Sea area, via a stable isotope approach, in relation to the wind turbine impact. Fur was collected from bat carcasses originating from wind farms in Dobrogea, Romania and from living individuals captured at Canaraua Fetii and Babadag regions. The stable isotope (δ2Hf) analysis...

Certain bat species rely on karstic environments to perform part of their annual biological cycles. This study shows bat climatic preferences and roost selection in six caves from Romania. Four of these are show-caves (Muierilor, Polovragi, Meziad and Valea Cetății), one has restricted human access (Cloșani) and the last has uncontrolled access (Gu...

We focus on the tectonic and structural frame in which the caves and potholes in the central area of the Făgăraș Mountains (South Carpathians) have developed. The major faults in the highly karstifiable areas of Piscul Negru and Mușeteica were identified, measured and correlated to cave development patterns. Preliminary microtectonic analyses were...

The presence of wilderness areas in the Carpathian Mountains suggests that the Natural habitats that are part of this region still maintain their ecological functionality, but there are chances that some of these were not included into the network of protected Natural areas. There is thus an urgent need to find a method that can reliably identify t...

Spatial distribution analyses of fossil bones are often used in cave taphonomy for i) assessing directly the size of a given fossil population and ii) indirectly, for palaeo-environmental reconstructions. Urşilor Cave from northwestern Romania hosts one of the richest MIS 3 cave bear bone assemblages of Europe, and as the nature of the bone deposit...