Southeastern Carpathians Research Articles

Forest floor nematode communities and associated tree canopies: Is there an ecological linkage?

We searched for patterns supporting the hypothesis of compositional and functional linkage between forest floor nematode communities and dominant tree canopies, while controlling for some relevant soil and climate variables. Twenty-one forest sampling sites scattered throughout the South-Eastern Carpathian basin were selected under spruce, beech, and hornbeam-oak canopies. The relative contribution of forest canopy type to nematode assemblage differentiation was estimated through nematode taxonomic composition and feeding guild structure. The forest canopy type had a significant effect on nematode taxon/feeding guild composition and diversity at stand level. Several (diagnostic) nematode taxa and feeding guilds were positively associated with and accurately predicted the forest canopy types considered. Apart from the herbivorous nematodes, all the other trophic guilds were significantly related, in terms of their relative abundance, to the forest canopy type. Both nematode taxonomic and trophic diversity were significantly higher under beech canopy compared with its two counterparts. The highest total nematode beta diversity, either taxonomic or trophic, was attained between hornbeam-oak and spruce canopies. Nematode taxonomic and trophic beta diversity between forest canopy types were largely determined by taxon replacement and respectively, by a nested trophic structure. Overall, four concordant and two discordant patterns were revealed between nematode taxon and feeding guild composition with respect to overlying forest canopy, all underpinning the addressed ecological linkage. The present results bring evidence regarding the important contribution of the forest canopy, along with climatic variables, in driving the taxonomic and functional composition/diversity of nematode communities from the soil organic horizon.

Crustal and upper mantle 3-D Vs structure of the Pannonian region from joint earthquake and ambient noise Rayleigh wave tomography

SUMMARY The Pannonian Basin, situated in Central Europe, is surrounded by the Alpine, Carpathian and Dinaric orogens. To understand its tectonic characteristics and evolution, we determine a shear wave velocity model of its crust, mantle lithosphere and asthenosphere consistently by jointly inverting Rayleigh wave phase velocities measured consistently from earthquake (EQ) and ambient noise (AN) data. For the AN data, continuous waveform data were collected from 1254 stations, covering an area within 9° from the centre of the Pannonian Basin during the time period from 2006 to 2018. This data set enabled the extraction of over 164 464 interstation Rayleigh phase-velocity curves, after applying a strict quality control workflow. For the EQ data set more than 2000 seismic events and about 1350 seismic stations were used in the broader Central and Eastern European region between the time-span of 1990 to 2015, allowing us to extract 139 987 quality controlled Rayleigh wave phase-velocity curve. Using the combined data set, a small period- and distance-dependent bias between ambient noise and earthquake measurements, mostly below 1 per cent but becoming larger towards longer periods has been found. After applying a period and distance dependent correction, we generated phase-velocity maps, spanning periods from 5 to 250 s. 33 981 local dispersion curves were extracted and a new approach is introduced to link their period-dependent roughness to the standard deviation. Using a non-linear stochastic particle swarm optimization, a consistent 3-D shear wave velocity model (PanREA2023) encompassing the crust and upper mantle down to 300 km depth was obtained with a lateral resolution reaching about 50 km at the centre of the study area for shorter periods. The crust beneath the Carpathian orogen exhibits a distinct low-velocity anomaly extending down to the Moho. It is referred to as Peri-Carpathian anomaly. Similar anomalies were observed in the Northern Apennines, while the Eastern Alps and Dinarides, as collisional orogens, generally demonstrate higher velocities in the upper crust. High crustal shear wave velocities are also evident in the Bohemian Massif and the East European Craton. The brittle upper crust of the Pannonian Basin is characterized by alternating NE–SW trending high- and low-velocity anomalies: the western and central Pannonian low-velocity anomalies and the Transdanubian and Apuseni high-velocity anomalies related to Miocene sedimentary basins and intervening intervening interbasinal highs exposing Pre-Cenozoic rocks including crystalline basement rocks. Beneath the Southeastern Carpathians, a NE-dipping slab was identified, extending to depths of at least 200 km, while a slab gap is evident beneath the Western Carpathians. A short south-dipping Eurasian slab was imaged beneath the Eastern Alps down to only 150–200 km depth. The Adriatic lithosphere is subducting near-vertically dipping beneath the Northern Apennines, and a slab gap was observed beneath the Central Apennines. In the Northern Dinarides, a short slab was evident, reaching depths of around 150 km. The Southern Dinarides featured a thinned but possibly incompletely detached slab.

Composition of Natural Forest Types—Long-Term Goals for Sustainable Forest Management

The high stability of stands with structures similar to natural ecosystems justifies adopting their composition as a management goal. Increasing the proportion of spruce in mixed forests and in deciduous forests in the Romanian Carpathian region, against the backdrop of climate change, may affect their stability. The natural distribution of tree species was investigated to establish natural forest types for defining future stand compositions. A forest in the Făgăraș Mountains of the Southeastern Carpathians was selected, and the mapping results were applied to a management unit of 4303.2 ha. Site conditions (e.g., altitude, exposure, etc.) are ecologically determined factors influencing the natural distribution of tree species and significantly influence species proportions. These factors, incorporated into models, estimate species proportions in future stand compositions with a root mean square error (RMSE) of 20%–24%. By adopting forest-type compositions as a management goal, the composition at the management unit level approaches that of natural ecosystems existing in 1950: Norway spruce (Picea abies (L.) Karst.) will decrease from 80.5% to 32.4%, while European beech (Fagus sylvatica L.) will increase from 12.5% to 41.7%, Silver fir (Abies alba Mill.) from 0.6% to 15.8%, and other species from 6.4% to 10.1%. Restoring ecosystems affected by their transformation into spruce monocultures leads to increased biodiversity and mitigates the effects of climate change, ensuring the long-term functionality of forest ecosystems, which are essential conditions for sustainable forest management.

Leucojum vernum in Intorsurii Mountains (South- Eastern Carpathians)

This study investigates the population structure and ecology of the species Leucojum vernum (spring snowflake) in Întorsurii Mountains, South-Eastern Carpathians, where was supposed to be extinct. The research objectives were: (1) to identify the species in Popii Valley, (2) to estimate its population size, (3) to map the species extent, (4) to delineate the species ecological niche, (5) to identify and describe the vegetation types where the species grows, (6) to identify the co-occurring species as indicators of suitable habitat for L. vernum, and (7) to assess the species conservation status in Popii Valley and in Romania. Identification and description of the species population relied on an intensive survey in the whole watershed of Popii Valley. A detailed vegetation map of the Popii Valley watershed was created. For the description of the species habitat, 27 sampling plots were used. The species ecological preferences were drawn by means of the indicator species analysis, climate and geological maps. Climate suitability was checked by projecting the analyzed population in the bioclimatic envelope of L. vernum in Romania, using principal components analysis (PCA) ordination and classes of aridity index. The assessment of the conservation status followed the principles and methodological standards for monitoring protected species at the European Union and global level. In the studied area L. vernum was found in four forest associations, on moist and nutrient-rich soils. The indicator species of the suitable/unsuitable habitats were identified with the help of the phi coefficient of association between species. The population size and species habitat are in favorable conditions, although signs of bulbs collection for gardening were observed. These findings were discussed in a national and global context. An updated map for species extent in Romania was provided in order to support the assessment of the global and national IUCN category.

Large Differences in Bud Burst and Senescence between Low- and High-Altitude European Beech Populations along an Altitudinal Transect in the South-Eastern Carpathians

Large Differences in Bud Burst and Senescence between Low- and High-Altitude European Beech Populations along an Altitudinal Transect in the South-Eastern Carpathians

The relationship between the loess stratigraphy in the Vojvodina region of northern Serbia and the Saalian and Rissian Stage glaciations – a review

The regional loess stratigraphy in the Vojvodina region, in the southeastern Carpathian Basin, has often been successfully correlated to the global palaeoclimate. This is a quasi‐continuous sedimentary record that provides detailed environmental reconstruction during the last four glacial/interglacial cycles. In this study, we present a standardized loess stratigraphy and illustrate how it correlates with the marine oxygen isotope and Chinese loess stratigraphical records. We argue that the loess stratigraphy in Vojvodina region is an important link in the integration of European terrestrial stratigraphical schemes and the deep‐sea stratigraphical model. We highlight how the loess record can better illustrate terrestrial environmental change through multiple glacial cycles than other records, such as glacial records. The investigated loess record enables direct links to be made between the loess sediments and their glacial sources. This reveals evidence of glaciations during every glacial cycle of the Saalian Stage complex, equivalent to Marine Isotope Stage (MIS) 10, 8 and 6. Therefore, Serbian loess has the potential to provide a direct link between terrestrial glaciations and wider records of global climate change, which is an enigma for many other continental records. These loess records display a strong relationship with the intensity of European glaciations during different glacial cycles. Loess sedimentation rates are highest in the most intensive European glaciation of the Saalian complex (MIS 6) and much lower during the weaker ‘missing’ glaciations equivalent to MIS 8 and 10. A key observation from the Vojvodina loess is the gradual increase in interglacial aridity through the late Middle Pleistocene. The explanation for the progressively increasing aridity in the investigated region at this time is still unclear. However, this trend is consistent with the idea of the Saalian complex as representing a 400 ka mega glacial cycle modulated by shorter classic 100 ka glacial cycles.

New insights regarding the taxonomy and phylogeography of Onobrychis montana DC. subsp. transsilvanica (Fabaceae)

Onobrychis montana DC. Subsp. transsilvanica (Simonk.) Jáv. (Fabaceae) is a plant taxon, endemic to the South-Eastern Carpathians, whose taxonomic status is treated inconsistently by the classic taxonomy based on morphological traits. In a previous study, by sequencing several chloroplast DNA regions and AFLP genotyping, we tried to elucidate the controversy concerning its taxonomic status in relation to the more widespread O. montana DC., and determined its phylogeographic structure within the Carpathians. The present study, based on DNA fingerprinting by seven SSR markers, brings more insights on this problematic taxon by conferring higher resolution and sub-clustering previously identified phylogeographic groups. However, the newly SSR genetic data are in agreement with molecular evidence revealed by AFLP and chloroplastic SNPs and do not support O. montana DC. Subsp. transsilvanica (Simonk.) Jáv. As a distinct species from O. montana DC.

The link between lithospheric scale deformations and deep fluid emanations: Inferences from the Southeastern Carpathians, Romania

Understanding the formation, migration and emanation of deep CO2, H2O and noble gases (He–Ne) in deep-seated deformation settings is crucial to know the complex relationship between deep-originated fluids and lithospheric deformation. To gain a better insight into these phenomena, we studied the origin of H2O, CO2 and noble gases of gas-rich springs found in the Târgu Secuiesc Basin located in the southeasternmost part of the Carpathian-Pannonian region of Europe. This study area is one of the best natural examples to understand the connection between the deep sources of gas emanations and deep-seated deformation zones, providing an excellent analogue for regions with similar tectonic settings and fluid emanation properties. We studied the δ2H and δ18O stable isotopic ratios of the spring waters, and the δ13C, He and Ne stable isotopic ratio of the emanating CO2-rich gases dissolved in the mineral spring waters in Covasna town and its vicinity. Based on the δ2H, δ13C, δ18O stable isotopic ratios, the spring waters and the majority of the gases are released through two consecutive fluid infiltration events. The preservation of the metamorphic signal of the upwelling H2O is linked to the local groundwater flow and fault abundancy. Furthermore, the noble gas isotopic ratios show a high degree of atmospheric contamination in the dissolved water gasses that is most likely related to the local hydrogeology. Nevertheless, the elevated corrected helium stable isotopic ratios (Rc/Ra) of our filtered data suggest that part of the emanating gases have a potential upper mantle source component. Beneath the Southeastern Carpathians, mantle fluids can have multiple origin including the dehydration of the sinking slab hosting the Vrancea seismogenic zone, the local asthenospheric upwelling and the lithospheric mantle. The flux of the mantle fluids is enhanced by lithospheric scale deformation zones that also support the fluid inflow from the upper mantle into the lower crust. The upwelling CO2–H2O mantle fluids may induce the release of crustal fluids by shifting X(CO2) composition of the pore fluid and, consequently, initiating decarbonisation and devolatilization metamorphic reactions as a result of carbonate and hydrous mineral destabilisation in the crust. Based on the p-T-X(CO2) conditions of calc-silicates and the local low geotherm, we emphasise the importance of the upwelling fluids in the release and upward migration of further H2O and CO2 in the shallower lower and upper crust. We infer that migration of deep fluids may also play an important role in addition to temperature control on the generation of crustal fluids in deep-seated deformation zones.

Reconstructed Malacothermometer July Paleotemperatures from the Last Nine Glacials over the South-Eastern Carpathian Basin (Serbia)

In this study, the compiled malacological record of the two most important loess–palaeosol sequences (LPS) in Serbia was used to reconstruct the Malacothermometer July Paleotemperature (MTJP) of the last nine glacials. The sieved loess samples yielded shells of 11 terrestrial gastropod species that were used to estimate the MTJP. Veliki Surduk (covering the last three glacial cycles) and Stari Slankamen (covering the last fourth to ninth glacial cycle) LPSs previously lacked the malacological investigations. After the sieving, a total of 66,871 shells were found, from which 48,459 shells were used for the estimation of the MTJP. Through the studied period, the reconstructed MTJP was ranging from 14.4 °C to 21.5 °C. The lowest temperature was recorded during the formation of the loess unit L5, equivalent to the Marine Isotope Stage (MIS) 12. The second-coldest summers were occurring during the MIS 16 glacial. Although the warmest glacial was L8 (MIS 20) according to MTJP, these July temperatures might be overestimated due to only two samples from the poorly preserved L8 unit. The malacological material derived from the loess units at Veliki Surduk and Stari Slankamen LPSs showed great potential for July temperature reconstruction, as the comparison with other regional records showed similar climate changes. Further work is necessary to validate the age scale of the oldest samples, and a higher resolution sampling could lead to more detailed July temperature fluctuations, as was shown for the youngest glacial in this study. Likewise, estimating the July temperature using different proxies (e.g., pollen) from the same LPSs could be used to confirm the observed climate trends.

Phylogeographic pattern of the high-alpine plant species Eritrichium nanum (Boraginaceae) within the Carpathians

The Carpathians represent not only a European hotspot of plant diversity for both species richness and endemism, but also an important stepping-stone area in historical migrations between the flora of the Asian and European mountain systems and a starting point of postglacial recolonizations for many species. Yet, until recent years, phylogeographical studies for alpine or arctic-alpine plants were focused on the Alps, whereas peripheral mountain ranges, including the Carpathians, were either neglected or insufficiently sampled. In this study, we aimed to complement the Alpine phylogeographic structure of an emblematic high-alpine European endemic taxon, Eritrichium nanum, by focusing on the Carpathian range of the species. We sampled nine populations from the South-Eastern Carpathians and performed ITS1 sequencing and AFLP fingerprinting. In case of ITS1 region, all the populations, no matter of their geographic origin, presented the same ribotype. The AFLP analysis indicated that, within the Carpathians, the extant populations of E. nanum comprised two major allopatric lineages. One important result of the research was the discovery that the species’ sole important genetic break was located in the Southern Carpathians, separating populations of the Retezat Mountains from all the others in the Carpathians.

On the seismic wave attenuation at the bend of the Southeastern Carpathians

On the seismic wave attenuation at the bend of the Southeastern Carpathians

Traditional ecological knowledge to traditional foods: The path to maintaining food sovereignty in Hutsulshchyna

The various ecosystems of the Carpathian Mountains spanning Europe, are a rich refuge for culturally important, endemic plant species as well as large carnivores. These biologically diverse landscapes are a principal source of subsistence to 16 million people, including various ethnographic groups. This paper focuses on a case study involving Hutsul communities, an ethnographic group of traditional pastoral highlanders, in the Southeastern Carpathian Mountains of Ukraine. Given ecosystem, climatic, and cultural challenges, especially the rise of illegal logging, commercial harvesting, increased frequencies of flooding, and now a war, Hutsul communities face extensive threats to maintaining socio-ecological resilience in the region. A contributing factor to the region's centuries-long resilience is traditional ecological knowledge upholding food sovereignty as seen through traditional foods derived from Carpathian Mountain ecosystems. Traditional ecological knowledge (TEK) is as a dynamic, generationally-held knowledge base, where language, gathering practices, landscape and culture inform livelihoods. In this article, we seek to answer the following series of questions within Hutsul communities: (1) What does TEK look like in the region? (2) What are the regional environmental challenges? (3) Given these challenges, what are coping mechanisms and adaptive strategies grounded in TEK, ensuring a resilient food sovereign system? Mixed methodologies guided by community-based participatory action research methods (CBPAR) between 2017 and 2019 provide a rich, context-driven perspective on regional TEK. Radiating out from the historical, cultural Hutsul capital, Verkhovyna, 40 experts (including knowledge holders, elders, foresters, and community members) were interviewed in 8 neighboring villages. We, along with Hutsul experts, explore the presence of traditional ecological knowledge (TEK) in Hutsulshchyna by identifying 108 culturally important species including wild plants (74 species), cultivated plants (23 species), fungi (9 species) and lichens (2 species); these species are gathered in 10 habitats with varying degrees of human interaction. We analyze species' presence in traditional foods in the past and present day, as well as contextualize regional environmental challenges impacting TEK practices, and responses to these challenges (coping mechanisms and adaptive strategies). Despite various regional challenges, we conclude that TEK provides a resilient foundation for supporting food sovereignty as seen through the presence of traditional foods.

Vrancea intermediate-depth focal mechanism catalog: a useful instrument for local and regional stress field estimation

The Vrancea seismic zone, located in the bend region of the South-Eastern Carpathians, is a unique area with both crustal and intermediate-depth seismic activity and is known as one of the most active seismic area in Europe. Moderate crustal seismicity is recorded all over the Carpathian region, but the far more intense activity occurs in a small subcrustal seismogenic volume beneath the SE‐bend of the Carpathian arc with about 20 × 50 km lateral and 110 km vertical extent (70–180 km depth). A unique slab geometry, likely preserved until the present, causes stress localization due to the slab bending and subsequent stress release resulting in large mantle earthquakes in the region. The main focus of this study is to determine the focal mechanisms for events with a magnitude larger than 2.7, between 2005 and 2020 and evaluate the current stress field along the Vrancea subcrustal region, from the derived fault plane solutions. The main style of faulting for Vrancea subcrustal events presents a predominant reverse one, with two main earthquakes categories: the first one with the nodal planes, oriented NE–SW parallel with the Carpathian Arc and the second one with the nodal planes, oriented NW–SE perpendicular on the Carpathian Arc. The results of stress inversion indicate a dominant thrust faulting style, with an average stress regime index of 2.87. The stress pattern shows similar partitioning with vertical extension in the slab and no preferred orientation in the overlying crust, showing a transition regime from the extensional regime in the Moesian Platform to the compressional regime in the Vrancea subcrustal zone.

New faunistic data on the family Capniidae (Plecoptera) from the Carpathians (Romania and Ukraine)

Zwicknia acuta is reported for the first time from the South-Eastern Carpathians (Romania and Ukraine). Additionally, another stonefly species, Zwicknia kovacsi, previously described from Romania, is added to the Plecoptera fauna of Ukraine. New faunistic data are presented for two other winter-active species, Capnia vidua rilensis and Zwicknia bifrons. Based on a combination of personal and literature data we present a checklist of Capniidae from Romania and provide a key for them.

Present-day stress field pattern in the Vrancea seismic zone (Romania) deduced from earthquake focal mechanism inversion

Vrancea seismogenic zone in the South-Eastern Carpathians is characterized by localized intermediate-depth seismicity. Due to its complex geodynamics and large strain release, Vrancea represents a key element in the Carpatho-Pannonian system. Data from a recently compiled catalogue of fault plane solutions (REFMC) are inverted to evaluate stress regime in Vrancea on depth. A single predominant downdip extensive regime is obtained in all considered clusters, including the crustal layers located above the Vrancea slab. The prevalent stress regime confirms previous investigations and requires some mantle-crust coupling. The S3 principal stress is close to vertical, while S1 and S2 are horizontal, oriented perpendicularly and respectively tangentially to the Carpathians Arc bend. This configuration is present at any depth level. According to seismicity patterns, there are two main active segments in the Vrancea intermediate-depth domain, at 55 – 105 km and 105 – 180 km, both able to generate major events. The configuration of the tectonic stresses as resulted from inversion is similar in both segments. Also, high fault instability (I > 0.95) is characterizing the segments. The only notable difference is given by the friction and stress ratio parameters which drop down in the bottom segment from μ = 0.95 to μ = 0.55 and from R = 0.51 to R = 0.29. This variation is attributed to possible weakening processes activated below 100 km depth and can explain the intensification of seismicity production as earthquake rate and average energy release in the lower segment versus the upper segment.

Syntaxonomic characterization of the vegetation belts from the South-eastern Carpathians (Romanian Carpathians)

Syntaxonomic characterization of the vegetation belts from the South-eastern Carpathians (Romanian Carpathians)

The ranked species occupancy curves reflect the dominant process of species sorting: Evidence from forest/scrub communities

AbstractQuestionsAbiotic filtering, competitive interactions and niche pre‐emption effects, as important drivers of the species sorting in plant communities, were hypothesised to be responsible for the amount of concavity and shoulder distinction in ranked species occupancy curves (RSOCs). In connection with the intermediate productivity hypothesis, we proposed an adjustment and extension of the RSOC models concerning the ecological mechanisms underlying their shaping. We aimed at estimating the effects of the variation in resource availability and functional species composition on the RSOCs of 30 woody vegetation syntaxa.LocationLow plains to the subalpine belt (southeastern Carpathians) throughout Romania.MethodsThe fraction of vascular plant species with either low (< 3) or large (>7) Ellenberg ecological indicator values were used as proxies for abiotic variables. Both the standardised effect size of homotoneity (SES‐h, estimated by contrasting empirical vs null RSOCs) and the regression parameters of the fitted RSOCs were used, after adjusting them for differences in sampling scale, as shape descriptors.ResultsThe empirical RSOCs were all fitted best by the power exponential function. With increasing fraction of ruderal species and canopy openness, the slopes of RSOC's heads became gentler (larger power parameter). Higher levels of soil fertility towards lower elevations translated in reduced concavity of the RSOCs (larger exponential parameter). Larger/smaller SES‐h were associated with richer/poorer habitat‐specific species pools that were ascribed to low‐elevation, open‐canopy vegetation (oak‐dominated forests, shiblyak woodlands, secondary scrubs) and, respectively, (sub)montane, closed‐canopy, mixed beech or spruce forests and sub‐alpine scrubs.ConclusionsDense species packing and even niche partitioning in communities developed in moderately productive sites are associated with shoulder‐free, long‐tailed, slightly concave RSOCs. Conversely, strong filtering in stressful environments and/or low light availability under closed, woody canopies are related to steep, short‐tailed, exponential‐like RSOCs. The availability of resources and the equitability of niche partitioning, underlying the process of species sorting during plant community assembly, play a major role in shaping the RSOCs.

Detecting trends in the quality and productivity of grasslands by analyzing the historical vegetation relevés: A case study from Southeastern Carpathians, Vlădeasa Mountains (Romania)

Grassland ecosystems are essential for biomass production but are prone to degradation if management practices are inappropriate. Thus, it is necessary to optimize grazing management since the grazing practices and grassland status are interconnected. Herbage mass production and forage quality of the plant species are among the most important factors for grazing livestock performance, grassland carrying capacity, and their sustainable management. We employed optimized methods for the analysis of two historical vegetation datasets (from 1970 and 2008), along with the statistical data on livestock numbers and types from three administrative units within the Vlădeasa Mountains area, in the Romanian Carpathians. We looked for trends in grassland quality and productivity and explored their connections to grazing management descriptors and practices. We identified a small but statistically significant decreasing trend between the two periods in both pastoral value (from 63.80 to 61.43) and productivity (from 10.80 t ha-1 to 9.18 t ha-1). The decline in grassland quality and productivity may be associated with the sharp decrease in livestock numbers (from 9,688 LU to 5,085 LU) and the replacement of cattle by sheep as the dominant livestock type. The abandonment of grasslands and traditional practices also increased the deviation from the optimum of the actual stocking rate. This approach can be used as a model for other areas where time-series vegetation data are available from phytosociological literature and/or databases. These insights can be used to design adaptive grazing management plans to optimize grazing management according to the carrying capacity of the grassland ecosystems.

Isolating Lithologic Versus Tectonic Signals of River Profiles to Test Orogenic Models for the Eastern and Southeastern Carpathians

AbstractFluvial morphology is affected by a wide range of forcing factors, which can be external, such as faulting and changes in climate, or internal, such as variations in rock hardness or degree of fracturing. It is a challenge to separate internal and external forcing factors when they are co‐located or occur coevally. Failure to account for both factors leads to potential misinterpretations. For example, steepening of channel network due to lithologic contrasts could be misinterpreted to be a function of increased tectonic displacements. These misinterpretations are enhanced over large areas, where landscape properties needed to calculate channel steepness (e.g., channel concavity) can vary significantly in space. In this study, we investigate relative channel steepness over the Eastern Carpathians, where it has been proposed that active rock uplift in the Southeastern Carpathians (SEC) gives way N‐ and NW‐wards to ca. 8 Myrs of post‐orogenic quiescence. We develop a technique to quantify relative channel steepness, the relative steepness index, based on a wide range of concavities, and show that the main signal shows an increase in relative steepness index from east to west across the range. Rock hardness measurements and geological studies suggest this difference is driven by lithology. When we isolate channel steepness by lithology to test for ongoing rock uplift along the range, we find steeper channels in the south of the study area compared to the same units in the North. This supports interpretations from longer timescale geological data that active rock uplift is fastest in the southern SEC.

UNHIDING FORESTED LANDSCAPES. THE ARCHAEOLOGICAL INDEX OF SOUTH-EASTERN CARPATHIANS

Starting with late 2018, a new archaeological research project has been unfolding in the framework funded by the Romanian Governmental Unit for Research and Development (UEFISCDI) dedicated to top fundamental research, as one of the few winners of 2016 edition (the single to date) of ‘Complex Projects for Frontier Research’ competition. The Project, whose aims and methods will be shortly presented further, is entitled ‘Hidden Landscapes: Exploratory Remote-sensing for the Archaeology of the Lost Roads, Borders and Battlefields of South-Eastern Carpathians’ (HiLands). It implements a systematic and diachronic investigation of the historic strategic circulation corridors crossing the South-Eastern part of the Carpathian Mountains – the main gate used along ages by people transiting between Transylvania and the Danube or the Black Sea. In order to achieve such aims we have been exploring, starting from large scale LiDAR surveys, the circulation corridors’ diachronic archaeological fingerprint, preserved in the shape of repeatedly fortified landscapes. LiDAR surveys have been carried on continuously since 2018, by airplane, but also with portable sensors based on SLAM technology. The results of the LiDAR explorations were enhanced by field surveys, geophysical prospections and pin-pointed excavations, in order to elucidate the nature of anomalies or better contextualize the significance and layout of the roads’ routes. The results of these activities are resumed in a constantly updated, open access, online data base of archaeological sites - The archaeological index of South-Eastern Carpathians (AISEC). The current contribution details the essentials of HiLands research (aims, concepts, methods), in order to introduce in the scientific circuit the AISEC’s functions and instruments, ready to be used as citable work.