Papers by Marcel Mîndrescu
Combining geomorphological approach and thermal monitoring for permafrost research in Rodna Mountains, Northern Romanian Carpathians
Forum geografic, 2021
In 1936, St. Pawlowski noticed a lack of balance in the distribution of cirques on either side of... more In 1936, St. Pawlowski noticed a lack of balance in the distribution of cirques on either side of the main crests of the Carpathians. The author named this glacial assymmentry. The simplest way of calculating it is by determining the ratio between the number of cirques and that of the glacial valleys situated on the main diametrically opposed slopes. Nowadays we call this ratio numerical glacial asymmetry. A special type of asymmentry is the selective glacial asymmetry, which analyzes different populations of glacial forms or glaciers in terms of positioning and degree of development. Out of those that we found, the most relevant such form is the main crest asymmetry. In the present study, this refers only to the glacial cirques situated tangentially to the main glaciated crests. Another type of asymmetry is determined by the ratio between the number, quality or dimension of the cirques to the surface unit. The role of these types of asymmetry is that of defining the distribution of...
Fallout isotope chronology of the near-surface sediment record of Lake Bolătău
Journal of environmental radioactivity, 2018
Fallout isotope (PbCs andAm) based dating has been carried out on the near-surface sediment core ... more Fallout isotope (PbCs andAm) based dating has been carried out on the near-surface sediment core collected from Lake Bolătău-Feredeu (Bukovina, Romania). The motivation was to improve the chronology of this recent section in connection with significant fluctuations observed in sediment accumulation rates, particle size distribution and primordial radioisotope (i.e.K andTh) composition. Previously only an extrapolation of a broad-range OxCal age-depth model, which was based on 8 AMS radiocarbon dates from the deeper part of a parallel sediment sequence and tentatively validated for the upper part using the double peaks of theCs activity concentration distribution, was available for the studied section (1-24 cm). Parallel to the previousCs measurement,Pb andRa (for a more detailed,Pb-based chronology),Am (for an additional time-marker), as well asK andTh concentrations have also been determined by gamma-spectrometry. In case of thePb-based chronology, due to a large deviation from a p...
Having been in existence for over 400 years, the natural dammed lakes formed by landslide movemen... more Having been in existence for over 400 years, the natural dammed lakes formed by landslide movements, Iezer and Bolătău, enjoy a high level of biodiversity, far above the average of the nearby land area covered with spruce tree forests. Belonging, from the very beginning of their existence, to a land property of Humor Monastery (1495) in Suceava County, the lakes were, for a while, ponds stocked with fish by the monks of that time. Both lakes hold waters situated in the first two water quality categories, the first for Bolătău, and the second for Iezer respectively. A very good quality of water, together with the slightly alkaline pH, allowed the formation of favourable conditions for salmonids (trout). In 1960 there has been a trout stocking action, with eastern brook trout (Salvelinus fontinalis Mitchell), but nine years later (1969), a new species, less vulnerable to these altitude conditions had to be introduced, the native trout (Salmo trutta fario) respectively. Stocking action...
New glaciated area in Rodna mountains-Tarnița la Cruce cirque
Even though we refer just to one former glacial site in the Rodna mountain area, this is importan... more Even though we refer just to one former glacial site in the Rodna mountain area, this is important from several points of view, firstly, this one was missed by previous researchers because of its lateral position from the axis of glaciation, the main ridge of the Rodna Mountains. Secondly, the cirque, with its altitude and shape, completes a population of cirques less represented in the Eastern Carpathians, compared with the Alps of Transylvania. These are called alpine cirques in the world literature, but we prefer this term of ‘Carpathian’ to fit better with the geomorphologic reality of the Romanian Carpathians. These alpine cirques have small dimensions, with apron floors where there were cold glaciers (in the ablation and accumulation areas situated inside the cirque) but short ones, which ended immediately after the floor, without being continued by glacier tongues. Nowadays, after the disappearance of Quaternary glaciers, these appear hanging on the high mountain ridges (bein...
The aim of this study is to make an inventory and a database comprising of all glacial lakes in t... more The aim of this study is to make an inventory and a database comprising of all glacial lakes in the Romanian Carpathians based on information provided by Gâstescu (1960), Pisota (1968, 1971), Decei (1981), Mindrescu (2006), and the data obtained in the field and laboratory by employing GIS techniques (ArcView, Global Mapper, Map Maker, Google Earth).
Remote Sensing Data and GIS Application for Landslides Mapping: A Case Study from India
Landslide is a major hydrogeological hazard that affects large parts of Himalayan area of Uttara... more Landslide is a major hydrogeological hazard that affects large parts of Himalayan area of Uttarakhand state in India. The developments in Geo-spatial technologies have opened the doors for detailed and accurate assessment of landslide prone area. This paper deals with a use of temporal remote sensing data and geographical information systems for landslide mapping. Six categories of controlling factors for landslides i.e. slope gradient, aspect, lithology, land use land cover (LULC), drainage density, lineament density are defined in this study. Normalized Difference Vegetation Index (NDVI) has been generated to identify the vegetated and non-vegetated area. During the study, it is clearly reveals that a total number of about 695 landslides spots covering an area of 2.30 sq. km. were mapped from Landsat-OLI-TRS image of 2015 whereas a total number of 157 landslides covering an area of 1.60 sq. km. were mapped from Landsat-ETM+ image of the year 2005. This study...
The largest wastewater treatment systems include Sorbulak and Kurty reservoirs, and the small sto... more The largest wastewater treatment systems include Sorbulak and Kurty reservoirs, and the small storage ponds were studied in the summer of 2017 and characterized mainly by organic pollution. Phytoplankton communities were represented by species tolerant of organic and toxic pollution. Cyanobacteria dominated in the reservoirs, and dinophyte algae were only in the Kurty Reservoir. According to the results of CCA analysis, only Cr and certain nutrients had a significant effect on the abundance of algae. A statistically positive significant association between the Shannon index and the average algal cell mass was established. The results obtained are a particular example reflecting the non-linearity of changes in plankton communities in the gradient of nutrient loading and eutrophication of aquatic ecosystems. ZUSAMMENFASSUNG: Die Rolle der Planktonalgen in der ökologischen Beurteilung von Staubecken im Einzugsgebiet des Ili-Balkhash. Die größten Abwasserbehandlungssysteme, das Sorbulak...
The study presents preliminary results regarding the use of electrical resistivity surveys in the... more The study presents preliminary results regarding the use of electrical resistivity surveys in the assessment of the internal structure of the glacial deposits from the Romanian Carpathians. ERT is a geophysical method used to quantify changes in electrical resistivity of the ground towards passing electric current across an array of electrodes and simultaneous measurement of the induced potential gradient. Using specific software the measurements are further processed and correlated with the topography in order to obtain bedrock resistivity features. Therefore, the method is useful to evaluate the characteristics of geological strata and is widely used for mapping shallow subsurface geological structures. In the mountain regions ERT studies have been applied in different glacial and periglacial geomorphological studies - for permafrost detection (in Romanian Carpathians - Urdea et. al., 2008; Vespremeanu-Stroe et al., 2012), slope deformation analysis, the assessment of slip surface...
Cirque form and development in Romania: Allometry and the buzzsaw hypothesis
Geomorphology, 2014
ABSTRACT A complete inventory of the 631 glacial cirques in Romania (and adjacent Ukraine) shows ... more ABSTRACT A complete inventory of the 631 glacial cirques in Romania (and adjacent Ukraine) shows that they are scale-specific and develop allometrically, extending in length more rapidly than they deepen: shape changes with size. Horizontal dimensions are around 700 m, vertical around 300 m. On each quantitative measure they form a single, unimodal population with limited variation in size (on a logarithmic scale). Cirque axial gradients (15–33°) are appropriate to occupation by rotationally-flowing glaciers. Lake basins are more common (26%) on granitic rocks, compared with 10.6% of all cirques. Geology also affects vertical dimensions and gradients. The relation between subjective (five grades) and objective measures of cirque development is shown by an r2 of 62% when Grade is predicted from maximum gradient, minimum gradient, and plan closure. Cirques larger in horizontal dimensions have better grades. Cirque floors cover around 28% of cirque map area. Larger cirques, and nested inner and outer cirques, are common in ranges that rose well above the snowline, and are associated with more extensive, more symmetrical glaciation and more cols. In size and shape Romanian cirques are similar to those in England and Wales. They are similar in some respects to those in part of the British Columbia Coast Mountains, except for smaller vertical dimensions. They may have developed only in the last few glaciations: mountain ranges can be ranked by degree of glacial modification and symmetry of glaciations. The ‘buzzsaw hypothesis’ is applicable only in the cores of the higher ranges: elsewhere, summit surfaces that are essentially preglacial survive.
Dendrochronological assessment and radiocarbon dating of subfossil coniferous macroremains excavated from a peat bog, Maramures Mts, Romania
ABSTRACT Fifty-six subfossil samples have been collected from a peat bog located on the Vinderel ... more ABSTRACT Fifty-six subfossil samples have been collected from a peat bog located on the Vinderel plateau, Farcău massif, Maramureș Mountains (Romania). The majority of wood-remains are Norway spruce (Picea abies) and Silver fir (Abies alba). The samples have been subjected to dendrochronological analysis and 7 samples were selected for AMS radiocarbon analysis. Seven floating chronologies have been developed from these subfossil samples, so far. The longest floating chronology contains 166 years and the shortest spans 47 years. Radiocarbon age obtained for the oldest and youngest samples are 1717 ± 19 yr 14C BP (255 – 388 cal AD) and 1039 ± 16 yr 14C BP (985 – 1023 cal AD), respectively.
Geomorphological record and equilibrium line altitude of glaciers during the last glacial maximum in the Rodna Mountains (eastern Carpathians)
Quaternary Research
In the eastern Carpathians the legacy of glaciation is preserved in several isolated mountain mas... more In the eastern Carpathians the legacy of glaciation is preserved in several isolated mountain massifs. This paper presents new mapping results of glaciated valley land systems in the Rodna Mountains, the highest part of the eastern Carpathians (2303 m above seal level). In most of the glacial valleys, the maximal Pleistocene extent is marked by freshly shaped moraines, which are referred in this study as the Pietroasa glacial stage and regarded as the last glacial maximum (LGM) advance. Only in three valleys do older Şesura glacial stage moraines (pre-LGM, likely Marine Oxygen Isotope Stage 6) occur. On the basis of the geomorphological record, we reconstruct the extent, surface geometry, and equilibrium line altitude (ELA) of Pietroasa-stage glaciers. The local ELA pattern of north-exposed glaciers in the Rodna Mountains shows a rising trend towards the southeast, which suggests dominant snow-bearing winds and orographically induced precipitation from the west. This finding fits we...
Central and Eastern Europe Paleoscience: From Local to Continental Perspective
Quaternary International
Regional Environmental Change
Worldwide accelerated forest loss and the associated environmental impacts are important 33 envir... more Worldwide accelerated forest loss and the associated environmental impacts are important 33 environmental concerns. In this study we integrate evidence from historical maps and a Landsat-34 Highlights inter-disciplinary approach assesses impacts of forest change on catchment scale geomorphic processes over the last 150 years multi-proxy, dated lake sediment profile records forest disturbance catchment impacts link between sediment changes and remote sensing reveals the nature and timing of recent catchment process responses to forest disturbances catchment-lake environmental management perspective in an environmentally important area
Meteorological Applications
Climate change effect on groundwater resources in Emilia-Romagna region: An improved assessment through NISTOR-CEGW method
Quaternary International
High-resolution projections of evapotranspiration and water availability for Europe under climate change
International Journal of Climatology
Fallout isotope chronology of the near-surface sediment record of Lake Bolătău
Journal of environmental radioactivity, 2018
Fallout isotope (PbCs andAm) based dating has been carried out on the near-surface sediment core ... more Fallout isotope (PbCs andAm) based dating has been carried out on the near-surface sediment core collected from Lake Bolătău-Feredeu (Bukovina, Romania). The motivation was to improve the chronology of this recent section in connection with significant fluctuations observed in sediment accumulation rates, particle size distribution and primordial radioisotope (i.e.K andTh) composition. Previously only an extrapolation of a broad-range OxCal age-depth model, which was based on 8 AMS radiocarbon dates from the deeper part of a parallel sediment sequence and tentatively validated for the upper part using the double peaks of theCs activity concentration distribution, was available for the studied section (1-24 cm). Parallel to the previousCs measurement,Pb andRa (for a more detailed,Pb-based chronology),Am (for an additional time-marker), as well asK andTh concentrations have also been determined by gamma-spectrometry. In case of thePb-based chronology, due to a large deviation from a p...
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Papers by Marcel Mîndrescu