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To assess aeolian relief dynamics in Pilkosios Dunes, 6 digital elevation models (DEMs) were prepared from the year 2010, for January, May and October of 2018, for May of 2019, and for November of 2022. These DEMs were then compared with each other to obtain elevation difference rasters through time. The obtained results indicated that elevation changes were directional through time, and their highest intensity coincided with the bare-sand surface class, where active blowout landforms were located. In these locations, the average negative elevation change rate was determined to be approximately 2 cm/year. To analyse the driving forces of these elevation changes, the relationships between a measure of elevation change and the tested factor characteristics were evaluated. The strongest relationship amongst all tested factors was found with the distance to the edge of grassland/bare sand. Locations that were farther away from this edge experienced a four times larger decrease in elevation, compared to areas closer to the edge. The distance to the shoreline, which is related to the absolute altitude, was also an important factor. This relationship can be summarized as follows: the lowest areas, which were further from the lagoon, were inactive; while the highest locations, which were closer to the shoreline, had the highest intensity of elevation change (averaging 0.5-0.7 m for adjacent to the shoreline locations and-1.7 m for locations ~ 300 m away from the shoreline). The slope factor described a trend of how the steepest slopes were decreasing in height by 2 m on average, while gentler slopes were mostly stable. [ABSTRACT FROM AUTHOR]

One of the most significant elements in the environment is arsenic (As). It is a hazardous metalloid that causes contamination of soil and water supplies as a result of numerous anthropogenic and natural sources. This pollution has detrimental impacts on human health and the ecosystem, making it crucial to monitor and control. The release of As from minerals into the soil and groundwater depends on the kind of mineral, pH, and redox conditions. As is typically found in two forms, trivalent arsenic (As3+, arsenite) and pentavalent arsenic (As5+, arsenate), both of which are inorganic and extremely deadly. When it comes to toxicity, arsenite is more dangerous than arsenate. Many people have been affected by As poisoning, due to exposure to As through water and food. Nowadays, accurate, fast measurement of As in the field remains a technical challenge; however, the X-ray fluorescence method is considered the most reliable, cost effective and capable of measuring a wide spectrum of metals. Health risk assessment is a crucial parameter to estimate the health hazards of the As molecule. The risk assessment approach proposed by the USEPA is common and widely used, amongst others. On the numerous health risk assessment models/frameworks used to foresee the carcinogenic and non-carcinogenic health impacts brought on by As-contaminated water, little information is currently accessible. This discussion also emphasizes the need for more study on the risks to human health posed by specific As species (both organic and inorganic) found in As-contaminated water. [ABSTRACT FROM AUTHOR]

On the Curonian Spit, the leading conservation issue is an opposition between the two contrasting nature-management principles—anthropocentricity and biocentricity. Land managers still waver between the two options, and the worst-case scenario materializes as a rapid proliferation of vegetation to the accumulative sandplain (palve). It results in the decline of sand drift to the mobile dunes. This article aims to examine how climate change affects the coastal dune landscape and to identify current dune protection and management priorities. The analysis of hydroclimatic changes; succession patterns in forest, herbaceous, and open-sand ecosystems; and phenological-based evaluation (NDVI from MODIS, 2000–2020), influencing possible management directions, were carried out in this study. The results show the significant hydro-climatic changes (air temperature, precipitation, and sea level) occurring over the last thirty years. They influence the prevailing overgrowth trends in recent decades, especially in herbaceous ecosystems. Therefore, if the EU's priority habitat—open-sand ecosystems—is to be preserved, the main policy recommendation is to apply adequate management tools such as grazing, and to pay more attention to the aesthetic ecosystem services of the mobile dunes parallel to biodiversity conservation. [ABSTRACT FROM AUTHOR]

Our paper reviews the current understanding of mercury in the environment of soil and sediment, including sampling, mobilization phases and analyzing methods. As a dangerous trace element, mercury has been shown to have several harmful effects on the environment. Mercury is released into the environment in a variety of chemical forms by both geogenic and human activities, with the majority of it coming from anthropogenic sources. It is affected by environmental conditions such as pH, redox potential, light and temperature-all of which determine its final chemical form-reactivity and toxicity. Methylmercury is considered one of the most poisonous forms found in nature. Considering the methodologies of the studies carried out we have found that the best technique for preserving methylmercury in soil and sediment samples is to freeze it immediately after collection. Organically rich soils are related to higher total mercury levels. Plants, such as Solanum nigrum (BR3) and Cynodon dactylon (BR2), can play an important role in mercury transport and accumulation. Solid-phase selenium causes faster demethylation and slower methylation of mercury. Methylmercury can increase by climate change and thawing; arctic permafrost is a potential source of Hg. Chemical vapor generation inductively coupled plasma mass spectrometry was used to develop a simple and quick method for measuring methylmercury; ultrasonic agitation and HNO3 were used for the process, the last of which proved to be the most efficient for selective extraction of methylmercury. [ABSTRACT FROM AUTHOR]

Soft-sediment deformation structures (SSDS) were identified in proglacial lacustrine (glaciolacustrine) sediments dated to 25–24 ka in the Buivydžiai outcrop, situated 30 km north of Vilnius in east Lithuania. These sediments accumulated in front of the last Weichselian glaciation maximum. The SSDS originated due to sandy silt liquefaction that disrupted the decimeter-thick silty sand interlayer. A NW-SE trending Buivydžiai fault was mapped in the proximity (8 km) of the Buivydžiai outcrop. The fault is well traced by a dense drilling in the sediments of the preglacial Daumantai Formation in the basal part of the Quaternary cover and attributed to the earliest Pleistocene. Depth difference of the formation along the fault is ~5–8 m; the northern flank is relatively uplifted with respect to the southern flank. The Buivydžiai earthquake was most likely induced by formation of an elastic forebulge flexure of the Earth's crust in front of the ice sheet. The magnitude was evaluated ~M = 6.0–6.5 and was most likely of shallow hypocenter depth. Furthermore, the Bystritsa (Belarus) earthquake of magnitude M = 3.5–4.0 was registered in December 1908 to the east (12 km) of the Buivydžiai outcrop along the Buivydžiai fault, which points to recurrent seismic activity of this fault. [ABSTRACT FROM AUTHOR]

The LiDAR-based digital elevation models of representative sample areas of morainic uplands of the Last (Weichselian) and pre-Last (Saalian) Glaciations in Lithuania were selected, and the terrain ruggedness index (TRI) and slope angles (SAs) were calculated. Former hypsometric studies of the topography in Lithuania were mainly dealing with the indication of maximum, minimum or average altitudes of relief derived from topographical maps. The SAs and TRI were calculated for the pattern areas (16 × 16 km) and their central smaller parts (5 × 5 km). In order to test how much morphometric parameters are dependent on the size of a sample area, smaller areas (located in the central parts of all five patterns) were analysed in a similar way, calculating SA and TRI values. The same order of the mean values of SAs was determined: the steepest slopes are characteristic of the Tauragnai, Plateliai and Vištytis patterns, and the gentlest slopes of the Varniai and Medininkai patterns. The steepest slopes and the highest TRI were determined for the marginal morainic uplands of the Last (Late Weichselian) Glaciation. The age of the insular Žemaičiai (Samogitian) Upland is under discussions so far. It was proposed by other researchers earlier that the core of the insular Žemaičiai Upland height formed during the Saalian Glaciation and this core is covered by a thin cover of Weichselian deposits. The morphometric parameters display that the highest maturity of the relief is characteristic of the southern slope of the insular Žemaičiai Upland and the Medininkai Upland of the Saalian age. This indicates a likely similar age of both uplands. [ABSTRACT FROM AUTHOR]

Extraction of mineral raw materials is increasing due to economic development and must be a normal process under due control and environmental supervision. However, there are a number of sites where the exploitation was stopped and mining sites were abandoned without proper restoration. Also, there are sites where mineral resources were or are extracted illegally thus making significant damage to the environment and economy. In order to collect information on land impacted by mining and extraction activities, for the first time a special project was carried out for the entire territory of Lithuania. The project consisted of gathering of information on damaged areas from various sources, field surveys and systematization of collected data. In order to obtain volumetric data, a special technology of aerial photogrammetry was developed and successfully applied. It was detected that the number of damaged sites > 0.3 ha reached up to 3,300. It is estimated that a total amount of illegally extracted minerals in last 15-20 years could be up to 15 million m3. The aerial photogrammetry was proved as a relevant technology and this could be applied for the control of the restoration of damaged land as well as for the monitoring of hazardous geological processes, e.g. coastal erosion, karst. [ABSTRACT FROM AUTHOR]

This study examines the relationship between the quantity of landfill leachate and attenuation distance of inorganic contaminants in the groundwater of open, semi-open and closed hydrogeological systems. Nearly 2,000 groundwater samples were collected and 12 inorganic chemical parameters were investigated, of which NH4 +, K+ and Fe were considered to be the most groundwater polluting chemical parameters. Analytical modelling of pollution migration, multivariate statistical techniques and a single factor pollution index method were applied for data processing. The results showed that irrespective of waste volume, the degradation coefficients of NH4 +, K+ and Fe were by 36-90% higher in the groundwater of open hydrogeological systems, where attenuation distances were by 14-56% shorter compared with those in closed hydrogeological systems. Also, the degradation coefficients of NH4 +, K+ and Fe+ in the groundwater of very small and small landfills were by 37-90% higher and attenuation distances were by 38-99% shorter compared with those in the groundwater of large and very large landfills. In the groundwater of very small and small landfills the difference between NH4 +, Fe and K+ attenuation distance in open and closed hydrogeological systems was about 89-97% lower than the difference in large and very large landfills. This finding indicates that the quantity of leachate is the main factor of attenuation of contaminants in groundwater. The results obtained in this research may be used to predict the dispersion of pollution in the groundwater of landfills located in similar hydrogeological systems and to take environmental protection measures. [ABSTRACT FROM AUTHOR]

The article contains results obtained from realization of the Polish and Lithuanian Baltic case study within the EU - FP 7 SubCoast project, which one of the primary aims was analysis of vertical ground movements, potentially causing geohazards in the coastal areas. To reach this goal Interferometrie Synthetic Aperture Radar (inSAR) data were obtained. For the Polish and Lithuanian Baltic coast ERS archive radar data were processed in order to provide Permanent Scatterer (PSInSAR, PSI) results that were then used to create the new innovative product - Dynamic DEM (DDEM). The deformation model defined by the SubCoast project normally needs to be created by merging InSAR, satellite navigation (GNSS), optical leveling and/or gravimetry measurements. Elaboration of DDEM enables more effective comparison between PS and tectonic features. Comparison of PS time series with groundwater changes shows a direct correlation, confirming impact of groundwater on subsidence or uplift of the ground surface. The results of the geological interpretation demonstrated that the examples of movements detected by PSI include subsidence linked to deformation of engineering constructions, compaction of organic or weak soils, and eolian accumulation or deflation processes of the sand dunes. For the Polish and Lithuanian coasts most of the area proved to be stable, nevertheless some local deviations up to -15 mm per year of movement were found. [ABSTRACT FROM AUTHOR]

The aim of the present study is to determine the location and morphometric characteristics of fluvial islands in a 234.5 km long reach of the River Neris (from the Lithuanian–Belarusian border till the mouth of the river), to evaluate the changes of their number, area and location that have occurred since the second half of the 20th century, and to analyse the main geological and hydrological factors which possibly have affected the development of these islands. The fluvial islands, i.e. river channel forms situated above the average long-term water level, separated from the land by river branches and generated by fluvial processes, i.e. by the interaction of ground and surface water flows or, in other words, by erosion–accumulation processes taking place in the river basin, are fully or partly covered by vegetation and best reflect the external scenery of the river. Islands are scattered over the whole investigated reach of the river, yet their number highly depends on morphometric, hydrogeological and geological conditions in different segments. Small islands are dominant (area < 1 ha, height up to 1 m). They account up to 89% of the total number of islands, yet their total area accounts only up to 33% of the total island area in the studied segment. The minimum number of islands (1 island in a 10 km long segment on the average) is observed in the segments where the river flows across morainic massifs and in the relatively straight segments. The maximum number of islands (1 island in a 1 km long segment) occurs downstream from the eroded segments where they occupy up to 5.4% of the river channel area. During the last 40 years, both the number and the area of fluvial islands have increased. The increasing area of the fluvial islands in the channel reduces transportability of the river flow. Investigations of the flow showed that at the end of the 20th — the beginning of the 21st century the annual peak discharge was 48% smaller than comparing to the end of the 19th start of the 20th century. Due to the reduction of the flood plain area and shorter duration of floods, the amount of sediments left in the flood plain has been continuously decreasing. This might have been caused by the increased sedimentation in the channel resulting in the intensive formation and accretion of the islands. In the future, the reduced transportability caused by the increasing number and area of the fluvial islands may predetermine higher and longer floods and higher flood hazards for the urbanised riverside territories under the conditions of the same discharge. [ABSTRACT FROM AUTHOR]

This paper focuses on the deep geothermal energy utilisation from the Lower Cambrian sandy silt-stone aquifer as a potential supply to the district heating system in Nīca, a small municipality in southwest Latvia. Based on this case study, we argue that it is technically and economically feasible to develop efficient geothermal heat stations in small municipalities rich in geothermal resources under three key preconditions: -sufficient extractable heat resources of the aquifer; - ready availability of a nearby deep well; and - a plan for environmentally acceptable disposal of the cooled geothermal water to the surface waters. If these conditions are met, the deep geothermal energy utilisation in a small-scale district heating system might be economically viable and possibly more sustainable than a larger district heating system, where high-pressure re-injection of the cooled geothermal water into deep rock aquifers is necessary. [ABSTRACT FROM AUTHOR]

Copyright of Estonian Journal of Earth Sciences is the property of Teaduste Akadeemia Kirjastus and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fossils of Mesozoic terrestrial vertebrates from Lithuania and the wider East Baltic region of Europe have previously been unknown. We here report the first Mesozoic terrestrial vertebrate fossils from Lithuania: two premaxillary specimens and three teeth that belong to Phytosauria, a common clade of semiaquatic Triassic archosauriforms. These specimens represent an uncrested phytosaur, similar to several species within the genera Paleorhinus, Parasuchus, Rutiodon and Nicrosaurus. Because phytosaurs are currently only known from the Upper Triassic, their discovery in northwestern Lithuania (the Šaltiškiai clay-pit) suggests that at least part of the Triassic succession in this region is Late Triassic in age, and is not solely Early Triassic as has been previously considered. The new specimens are among the most northerly occurrences of phytosaurs in the Late Triassic, as Lithuania was approximately 7–10° further north than classic phytosaur-bearing localities in nearby Germany and Poland, and as much as 40° further north than the best-sampled phytosaur localities in North America. The far northerly occurrence of the Lithuanian fossils prompts a review of phytosaur biogeography and distribution, which suggests that these predators were widely distributed in the Triassic monsoonal belt but rarer in more arid regions. [ABSTRACT FROM PUBLISHER]

Copyright of Geologija is the property of Lithuanian Academy of Sciences Publishers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An analysis of the dynamics of wind velocity along the Baltic coast of Lithuania is presented, based on data collected during field experiments in the summer, fall and winter of 1999.2001 and 2007.2009 at several sites (Būtingė, .aipiai, Smiltynė, Juodkrantė, Pervalka and Nida). The locations were chosen in order to encompass a wide spectrum of beach and dune ridge morphology. The relationship between wind velocity dynamics and coastal morphology was established, based on measurements of the slope angle, height and shape of the dune crest, as well as measurements of the morphology of the area behind the foredune ridge. On the basis of a comparison of near-surface wind velocity patterns, shear velocity (U*) and surface roughness length (z0) were calculated. It was determined that U* decreases from the middle of the beach towards the foredune toe, then increases towards the crest of the foredune and decreases down the lee slope. A direct correlation exists between U* and the stoss slope inclination, and the relative height of the foredune. Surface roughness length also increases from the beach towards the foredune crest. [ABSTRACT FROM AUTHOR]

An analysis of changes in the coastline of the Nemunas River delta front was undertaken with GIS based on cartographic material representing a 95 year period. Delta development was analysed comparing two time periods: 1910-1958 and 1958-2005. Quantitative indicators of land area determined during the study indicate that land in the northern part of the Nemunas delta front decreased more than 2.1 times in the 1958-2005 period, compared to the previous 1910-1958 period. The main reasons for the decrease of sediment accumula- tion are a decrease Nemunas River runoff, and a similar decrease of sediment particulates, due to anthropogenic activity and natural factors a rise in the water levels of the Baltic Sea and the Curonian Lagoon, as well as land subsidence in the Nemunas delta region. [ABSTRACT FROM AUTHOR]

An extensive area of distribution of palaeolacustrine sediments (sand, silt with humus and interlayers of gyttja), occurring above the Eemian (Merkinė) Interglacial deposits and below the relief forming the Upper Weichselian till, was determined in the Mickūnai glaciodepression (in the vicinities of Vilnius, East Lithuania). These sediments were interpreted as being formed in a shallow palaeolake or lacustrine system, which occupied the depression during the Early-Middle Weichselian. Four boreholes were drilled in the central part of the Mickūnai depression and their sections were studied using lithostratigraphic and pollen analyses and datings by the optically stimulated luminescence (OSL) method. On the basis of the lithological composition and pollen and spores data the studied sections were tentatively subdivided into thermomers (time periods with relatively warmer climate) and cryomers (time intervals with colder periods). In the Mickūnai site seven thermomers and eight cryomers occurring above the Eemian Interglacial were determined. The thermomers of Middle Weichselian, however, were defined only by slight climatic changes in the background of general climatic deterioration. The Mickūnai sequence reflects presence of nonglacial palaeoenvironments from the end of the Eemian Interglacial to the Late Weichselian ice advance. [ABSTRACT FROM AUTHOR]

Copyright of Geologija is the property of Lithuanian Academy of Sciences Publishers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Environmental Engineering & Landscape Management is the property of Vilnius Gediminas Technical University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Geochemical and lithological parameters of sapropel in lakes, combined with pollen data and radiocarbon 14C dating, contain a wide spectrum of environmental information. This includes records of fluctuations of water level and changes of conditions of sedimentation, accumulation of organic matter and chemical elements due to climate change, human impacts and other environmental changes. Rising concentrations of hazardous substances in the natural sediments are likely to be a high risk to the natural environment. At the same time, they can greatly reduce opportunities for environmental engineering of lakes. Four lakes with different trophic states and anthropogenic pressures were chosen for this study in Lithuania. Higher concentrations of elements like Cr, Cu and Zn were not only detected in the top most layers of sapropel but also in deeper layers and are attributed to lithogenic association of trace elements in such deep layers. Concentrations of Pb were detected only in upper layers of sapropel which indicates the impact of anthropogenic activity. The main source of heavy metals was multidimensional anthropogenic pollution leading to a biogenic–anthropogenic association of elements. Sapropel with low concentrations of heavy metals exhibits a different inter-association matrix because most of the elements tend to form lithogenic–clastogenic associations. [ABSTRACT FROM AUTHOR]

Copyright of Geologija is the property of Lithuanian Academy of Sciences Publishers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Information about several papers discussed at a conference entitled "Glaciotectonic structures, palaeobasins and neotectonic setting," organized by the Lithuanian Geological Survey and the Polish Geological Institute from August 27-31, 2007 in Lithuania is presented. Discussion focused on the relationship of glaciotectonic structures, digital mapping of subsurface relief and remote sensing. There were 20 oral presentations, poster session, and workshops conducted in the conference.

Coastal dunes are recognized as one of the most threatened ecosystems, the formation of which mainly depends on two opposite processes—sand dunes overgrowth and formation of open dunes. The application of cost-effective remote sensing methods permits monitoring the interaction of these two processes over a large area and long periods of time. Therefore in this study we assessed the links between hydro-meteorological parameters and the normalized difference vegetation index (NDVI) in Curonian spit coastal dunes landscape-a creation of human and nature integrity situated in the South eastern part of the Baltic Sea. Time series of NDVI (2000–2019) were obtained from the moderate resolution imaging spectro-radiometer and compared with hydro-meteorological parameters in three different ecosystems—forest, herbaceous and open sands. Moderate and strong positive correlation between NDVI and average wind speed was detected in non-forested ecosystems. Moderate positive correlation was detected between NDVI and the Baltic sea water level in all three analyzed ecosystems. Moderate positive correlation between NDVI and air temperature was found in forest ecosystem. This confirms that NDVI could be treated as an appropriate indicator, showing the interaction of coastal dunes overgrowth and formation of open dunes, and could be applied in its management that should be reconsidered under nowadays climate change. [ABSTRACT FROM AUTHOR]