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EN
The present study aims to understand the impact of submarine groundwater discharge (SGD) on a coastal area with different lithology and degrees of SGD. Sampling campaigns took place in Puck Bay and the Gulf of Gdańsk, southern Baltic Sea encompassing years between 2009 and 2021. The methodological approach combined geophysical characterization of the surface sediments with detailed spatial and temporal (isotope) biogeochemical investigations of pore and surface waters, and was supported by nearshore groundwater and river surveys. Acoustic investigations identified areas of disturbance that may indicate zones of preferential SGD release. The composition of porewater and the differences in the bay's surface waters disclosed SGD as common phenomenon in the study area. Regional SGD was estimated through a radium mass balance. Local estimation of SGD, based on porewater profiles, revealed highest SGD fluxes at the sandy shoreline, but relatively low elemental fluxes. Though SGD was low at the muddy sites corresponding elemental fluxes of nutrients and dissolved carbon exceeded those determined at the sandy sites due to intense diagenesis in the top sediments. SGD appears to be sourced from different freshwater endmembers; however, diagenesis in surface sediments substantially modified the composition of the mixed solutions that are finally discharged to coastal waters. Overall, this study provides a better understanding of the SGD dynamics in the region by a multi-approach and emphasizes the need to understand the processes occurring at the sediment-water interface when estimating SGD.
EN
Groundwater quality determination and age estimation in a desert landscape of El Golea province situated in the south of Algeria has been investigated in the present research paper. For this regard, 57 water samples were collected from an aquifer composed of two superimposed systems; phreatic and deep continental intercalary (CI) aquifers which are a part of the Northern Sahara Aquifer System (NWSAS). Samples were analyzed to assess the age and water quality using descriptive, multivariate statistics (PCA and HCA) and stable isotopes. It is revealed that more than 71% of the IC points are characterized by a water type (Ca2+, Mg2+) (HCO3 – )2 and more than 83% of the TC samples are defined by a water type (Ca2+, Na+) (HCO3 – , SO4 2 – ) and very high salt ions contents due to the influence of surface water, evaporate leaching and irrigation water return. The isotopic composition of samples of phreatic and CI aquifers shows a clear difference between the two qualities of water. The phreatic aquifer is characterized by the δ18O range from –4.68 to –6.1, whereas δ2H from –47.25 to –59.48 and CI with values of the δ18O range from –5.96 to –7.6, and δ2H range between –53.7 and –65.78 isotopic signature. The unconfined aquifer above IC forms a special case of a mixture of ancient water from deep horizons and recent water strongly enriched from shallow horizon lands.
3
EN
Establishing a chronology of events is a critical step in reconstructing the palaeoclimate and it is important for all types of environmental records, including speleothems. Here, we analysed a unique series of flowstones deposited between 3.2 Ma (marine isotope stage (MIS) Km3) and 0.08 Ma (MIS 5). The studied flowstones are located in a classic karstic environment, the Račiška Pečina Cave in south-western Slovenia. Further, a detailed chronology of events was constructed based on oxygen isotope stratigraphy (OIS), combined with magnetostratigraphy and U-series dating. Two curves were selected as reference records where the LR04 record was used as the global curve and a Mediterranean record was used as the regional curve. The Račiška Pečina profile was divided into two segments separated by a principal disconformity. The lower segment correlated better with the regional Mediterranean curve, while the upper segment was with the global LR04 curve. These findings suggest that the main factors controlling environmental conditions in the cave area changed between 3.2 and 0.8 million years ago.
EN
In a small-scale field experiment, we estimated the contribution of aboveground litter to the energy budget of different collembolan and earthworm species. In a 50-year-old spruce plantation, the natural spruce litter was replaced by an equivalent amount of maize litter. The natural difference in the isotopic composition of carbon (C) between the spruce and maize allowed us to estimate the proportions of different carbon sources in the tissues of soil animals. The dependence on litter-derived C was least pronounced in Collembola having low δ15N values, indicating the feeding on non-vascular plants. In contrast, collembolans having high δ15N values belonged to the food chains based on fresh plant residuals. These results suggest that different species of litter-dwelling collembolans may regulate substantially different energy channels. Some species of endogeic earthworms (Aporrectodea rosea and A. caliginosa) utilize aboveground plant residues, though soil organic matter and other belowground sources of carbon prevail in the energy budget of their populations.
EN
The A sulfur mine is located in the Iwate Prefecture of Japan. This mine has both surface and underground parts and was operated from the late 1800s to the late 1900s. Since the early 1900s, acid mine drainage (AMD) has been reported in this mine, and the waste water has been neutralized in a treatment plant since the mine was closed. Recently, reducing the AMD volume by decreasing water inflow to the underground mine has been considered as a way to reduce the AMD treatment cost. The first step in such an approach is to understand in detail the groundwater flow around the mine. However, part of the study area is covered by lava and comprises crystalline rocks with complicated structures, making it difficult to understand the groundwater flow. Therefore, the present study investigated the groundwater flow around this mine by focusing on water quality, such as pH and electrical conductivity (EC), stable isotopes (i.e. δ18O and δD) and 3H in the surface and ground water. The spatial distributions of pH, Stiff diagrams, and δ18O and δD values in the surface and ground water indicated that the groundwater flow system was divided into three basins in the study area, as predicted from geomorphological information. Moreover, the spatial distribution of δ18O and δD in the surface and ground water suggested that the groundwater recharged at the highest altitudes in the B mountain in the northwest of the mine might flow in the underground mine. Furthermore, the 3H values in the waste water discharged from the underground part of mine implied that the groundwater age was no more than approximately 60 years old.
PL
Kopalnia siarki znajduje się w prefekturze Iwate w Japonii. Kopalnia ma zarówno części naziemne, jak i podziemne i działała od końca 1800 roku do końca XX wieku. Od początku XX wieku odnotowano w tej kopalni kwaśny drenaż kopalniany (AMD), a ścieki były zneutralizowane w oczyszczalni do czasu zamknięcia kopalni. Ostatnio uznano, że zmniejszenie objętości AMD przez zmniejszenie dopływu wody do podziemnej kopalni jest dobrym sposobem na zmniejszenie kosztów neutralizacji AMD. Pierwszym krokiem w takim podejściu jest szczegółowa analiza przepływu wód gruntowych wokół kopalni. Jednak część obszaru objętego badaniem jest pokryta lawą i obejmuje skały krystaliczne o skomplikowanych strukturach, co utrudnia zrozumienie przepływu wód gruntowych. Dlatego w niniejszych badaniach określono przepływ wód podziemnych wokół tej kopalni, koncentrując się na jakości wody, określono parametry takie jak pH i przewodność elektryczna (EC), stabilne izotopy (tj. Δ18O i δD) oraz 3H w wodzie powierzchniowej i gruntowej. Przestrzenne rozkłady odczynu pH, wartości δ18O i δD w wodzie powierzchniowej i gruntowej wskazały, że system przepływu wód podziemnych został podzielony na trzy baseny na badanym obszarze, zgodnie z przewidywaniami z informacji geomorfologicznej. Ponadto rozkład przestrzenny δ18O i δD w wodach powierzchniowych i gruntowych sugerował, że wody gruntowe dopływające na najwyższych wysokościach w północno-zachodniej części kopalni mogą płynąć do części podziemnej kopalni. Co więcej, wartości 3H w ściekach odprowadzanych z podziemnej części kopalni sugerowały, że wiek wód podziemnych wynosił nie więcej niż około 60 lat.
6
Content available remote Trophic connectivity between intertidal and offshore food webs in Mirs Bay, China
EN
Trophic interactions are common worldwide, both within and between ecosystems. This study elucidated the trophic connectivity between intertidal and offshore zone, in Mirs Bay, China. The contributions of offshore suspended particulate organic matter (SPOM), intertidal macroalgae and epiphytes to consumer biomass were assessed, and the trophic pathways were identified through the use of stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) of basal sources and consumers. Mean δ13C values of basal sources had a wide range (-19.6‰ to -11.8‰) and were generally well separated in Mirs Bay. The average δ13C of consumers in Mirs Bay ranged from -19.2‰ to -11.8‰, reflecting a carbon source integrated from different primary producer signals. IsoSource model solutions indicated consumers assimilated organic carbon from a mixture of basal sources. Offshore SPOM carbon was the primary carbon source supporting most consumers in both intertidal and offshore zones. Intertidal macroalgae and epiphytes also accounted for a large fraction for some consumers. δ15N data indicated 5 trophic levels in Mirs Bay. Intertidal consumers, except for Capitulum mitella, had a TP (trophic position) between 2 and 3, and mainly included filter-feeders and grazers. In contrast, almost all offshore consumers had a TP of between 3 and 4 except for filter-feeders (zooplankton), planktivores (Clupanodon punctatus and Sardinella aurita) and piscivores (Gymnura japonica). The basal sources fueled consumer through two trophic pathways, each of which involved organisms of both intertidal and offshore zones, implying trophic connectivity between them in the Mirs Bay ecosystem.
EN
Oxygen and carbon isotope ratios of well-preserved calcitic bivalves from the Lower-lowermost Upper Kimmeridgian of Central Poland (SW margin of the Holy Cross Mountains) have been studied to reconstruct palaeoenvironmental conditions and variations in ancient water chemistry. Low and scattered δ18O and δ13C values of bivalve shells from shallow carbonate deposits of the Hypselocyclum and the Hypselocyclum-Divisum zone boundary (-3.5 to -1.5, and 2.6 to 4.0‰, respectively) are a result of salinity changes, and local variations in the composition of dissolved inorganic carbon (DIC) in conditions of restricted water circulation. A slight increase in bivalve δ13C values and more densely clustering of δ18O values is observed after the marine transgression at the Divisum-Mutabilis zone boundary. A global decrease of δ13C values of marine carbonates is partly recorded in Lower-lowermost Upper Kimmeridgian bulk carbonates from central Poland (from the Radomsko Elevation and the Wieluń Upland). Local negative shifts and the data scatter are, however, observed in rocks deposited in a very shallow environment of carbonate platforms during the Platynota and Hypselocyclum chrons. This interval corresponds to the uppermost part of the lowstand systems track of a major regressive trend, which had started already in the Late Oxfordian.
EN
Recent research shows that the last interglacial climate was more unstable in comparison to Holocene. Lack of suitable dating techniques and precisely defined absolute age benchmarks is one from main problems for present LIG studies. Therefore many of LIG chronologies base on indirect dating techniques like record alignment strategies. In this context, speleothems are valuable paleoclimate archives because of their capability to be dated by U-series method. In Europe LIG speleothem records are known mostly from western and central part of the continent. In this paper we present a 1,650 mm long stalagmite (ocz-6) from Bulgarian Cave Orlova Chuka. The ocz-6 stalagmite records the period of time ca. 129–112 ka. Ocz-6 stalagmite was analyzed in terms of stable isotopic composition of calcite and trace elements content. All analyzed geochemical proxies point to dynamic changes in the environment during the Last Interglacial time. At the time of interglacial development (129–126.5 ka), ocz-6 records shows systematic change in proportion of moisture delivered from Atlantic source and other sources. The beginning of last interglacial optimum is connected with a rapid change to more humid and warm conditions. During interglacial demise local climate become more dependent from regional settings.
EN
The Silurian Pelplin Formation is a part of a thick, mud-prone distal fill of the Caledonian foredeep, which stretches along the western margin of the East European Craton. The Pelplin Formation consists of organic carbon-rich mudstones that have recently been the target of intensive investigations, as they represent a potential source of shale gas. The Pelplin mudstones host numerous calcite concretions containing authigenic pyrite and barite. Mineralogical and petrographic examination (XRD, optical microscopy, cathodoluminoscopy, SEM-EDS) and stable isotope analyses (δ13Corg, δ13C and δ18O of carbonates, δ34S and δ18O of barite) were carried out in order to understand the diagenetic conditions that led to precipitation of this carbonate-sulfide-sulfate paragenesis and to see if the concretions can enhance the understanding of sedimentary settings in the Baltic and Lublin basins during the Silurian. Barite formed during early diagenesis before and during the concretionary growth due to a deceleration of sedimentation during increased primary productivity. The main stages of concretionary growth took place in yet uncompacted sediments shortly after their deposition in the sulfate reduction zone. This precompactional cementation led to preferential preservation of original sedimentary structures, faunal assemblages and earlydiagenetic barite, which have been mostly lost in the surrounding mudstones during burial. These components allowed for the reconstruction of important paleoenvironmental conditions in the Baltic and Lublin basins, such as depth, proximity to the detrital orogenic source and marine primary productivity. Investigation of the concretions also enabled estimation of the magnitude of mechanical compaction of the mudstones and calculation of original sedimentation rates. Moreover, it showed that biogenic methane was produced at an earlydiagenetic stage, whereas thermogenic hydrocarbons migrated through the Pelplin Formation during deep burial.
EN
Mixing of two water components and simultaneous contact with geogenic carbon dioxide are the characteristic features of waterfrom the Franciszek borehole in the Wysowa-Zdrój. During the last 45 years a systematic, slow decrease of water mineralization of this borehole has been observed. This may be due to several reasons: i) increased contribution of the infiltration component in the total inflow to the well, ii) gradual decrease of mineralization of diagenetic water or, iii) local changes of gaseous, geogenic carbon dioxide within the reservoir. Results of chemical and stable isotope measurements from the timespan of 42 years are discussed in the paper. The PHREEQC code was used in the analysis of chemical data and in the numerical simulation ofpossible processes leading to the observed changes in the water mineralization. Results of chemical calculations and stable isotope data are consistent and prove that decrease of water mineralization in the Franciszek borehole is caused by increased contribution of water of infiltration origin.
11
EN
The level of nitrate concentration in groundwater is a measure of the degree of contamination of the environment. However, it says little about the origin of nitrates. Stable isotopes of N and O (δ15 N and δ18 O) can differentiate between manure and chemicalfertilizers. This is the reason for undertaking a study on groundwater with high concentration of nitrates in the national monitoring network to recognize the origin of nitrates. Contrary to expectations, the results suggest that nitrates are derived mostly from manures and less from chemical fertilizers. Further studies are urgently needed.
EN
Groundwater age plays an important role in both development and management of groundwater resources. This is particularly true for groundwater systems being exploitedfor drinking water purposes and subject to anthropogenic stress. Environmental isotopes play a vital role in quantifying time scales of groundwater flow, ranging from fraction of a year to millions of years. Over the past several decades a large number of groundwater age indicators have been proposed. Apart of radioactive isotopes, also stable isotopes of water, isotopes of noble gases and anthropogenic trace substances present in the atmosphere have been usedfor this purpose. This work is focusing on methodological aspects of groundwater age determinations using tritium, radiocarbon and stable isotope composition of water. The discussion is based on a rich material available after several decades of application of environmental isotope techniques in groundwater studies in Poland.
PL
Jedna z pierwszych instalacji EGR (ang. Enhanced Gas Recovery – wzmożonego wydobycia gazu) na świecie funkcjonuje na złożu Borzęcin (SW Polska). Instalacja umożliwia zebranie doświadczenia w rozwoju technologii CCS (ang. Carbon Capture and Storage – wychwyt, transport oraz trwała izolacja CO2) na skalę przemysłową. Ze względu na niewielkie rozmiary złoża technologia ta daje możliwość rozwoju badawczego EGR, przy czym wszystkie procesy związane z zatłaczaniem ditlenku węgla i siarkowodoru są możliwe do obserwacji w stosunkowo niedługiej skali czasu. Głównym celem badań była próba oceny migracji zatłaczanych gazów poprzez pobór i analizę izotopów trwałych wodoru i węgla w gazach z poszczególnych otworów wiertniczych. Dzięki uzyskanym wynikom możliwa jest ocena migracji składników gazu ziemnego w złożu Borzęcin. W rezultacie przeprowadzonych badań otrzymano nowe narzędzie do oceny efektywności wzmożonej eksploatacji gazu, które następnie może być zastosowane w technologiach związanych z CCS. Skład izotopowy wodoru (n = 63) w metanie mieścił się w zakresie od –159,3‰ do – 85,2‰ (średnia –114,6‰), a skład izotopowy węgla (n = 92) w tym metanie wyniósł od –46,93‰ do –17,87‰ (średnia –35,22‰). Skład izotopowy węgla (n = 88) w ditlenku węgla osiągnął wartość od –23,33‰ do –3,11‰ (średnia –13,35‰).
EN
One of the first installations in the World, based on the EGR (Enhanced Gas Recovery) operates in Borzecin (SW Poland). Thus creating the opportunity to gather experience in the development of CCS (Carbon Capture and Storage) on an industrial scale. Due to the small size of the deposit, the technology allows great research opportunity to develop Enhanced Gas Recovery and all the processes associated with the injection of CO2 and H2S are possible to observe in a relatively short time scale. The main goal of the research is tracing migration fronts of injected gases threw sampling and isotopic analysis of gases from numeral boreholes. Gathered results gave the opportunity to get an appraisal of gas migration in the Borzecin deposit. Consequently a new tool for Enhanced Gas Recovery efficiency might be constructed with the potential of being applied in CCS technologies. Isotopic composition of hydrogen (n = 63) in methane varied from –159.3 to –85.2‰ (average –114.6‰) and isotopic composition of carbon including methane (n = 92) varied from –46.93 to –17.87‰ (average –35.22‰). Isotopic composition of carbon in carbon dioxide (n = 88) varied from –23.33 to –3.11‰ (average –13.35‰).
PL
Praca prezentuje własności fizyczne, skład chemiczny i zawartości naturalnych izotopów promieniotwórczych oraz względnych wartości δ18O, δ2H wybranych wód butelkowanych mineralnych, mineralnych i leczniczych z ujęć zlokalizowanych w różnych uzdrowiskach rehabilitacyjnych na Białorusi. Wody te zostały zebrane w okresie od 2012 do 2015 roku i analizowane w laboratoriach Wydziału Fizyki i Informatyki Stosowanej AGH oraz Wydziału Geologii, Geofizyki i Ochrony Środowiska AGH. W większości badanych wód dominują jony Cl-, SO42-, Na+ i Ca2+, a ich mineralizacja zmienia się w szerokim zakresie od kilku set mg/dm3 aż do około 150 g/dm3, pH od 6.6 do 9.1 a Eh od -283 do 259 mV. Stężenia izotopów radu zmieniają się od ≤ 5 mBq/dm3 aż do 17.6 Bq/dm3, a aktywność właściwa 228Ra zwykle jest wyższa od 226Ra. Stężenia izotopów uranu są zawarte w zakresie od poniżej 0.5 mBq/dm3 do 75 mBq/dm3 dla 238U i do ok. 300 mBq/dm3 dla 234U. Zawartości izotopu trytu są poniżej 1.1 UT, wartości d18O są w zakresie od -10.9‰ do -7.8‰ i d2H od -84‰ do -59,4‰. Te wartości wykazują, że w badanych wodach przeważa woda zasilana z okresu holocenu. Niektóre wody mineralne zawierają składniki swoiste (Rn, Br, Fe) które nadają im własności farmakodynamiczne.
EN
This work presents the physical properties, chemical composition, natural radionuclides’ concentrations and the relative values of δ18O, δ2H of selected bottled mineral, mineral and therapeutic waters of some water intakes localized at different therapeutic centers in Belarus. The water samples were collected in the period from January 2012 to June 2015 and analyzed at the Faculty of Geology, Geophysics and Environmental Protection and Faculty of Physics and Applied Computer Science laboratories, AGH University of Science and Technology in Kraków Poland. The results show that the dominating ions in the majority of waters are Cl-, SO42-, Na+ and Ca2+, the total dissolved solids (TDS) of the investigated waters ranges from several hundred mg/L to near 150 g/L, pH from 6.6 to 9.2 and Eh from -283 to 259 mV. The radium isotopes concentration ranges from below the limit of detection to 17 Bq/L, and the specific activity of 228Ra is often higher than those of 226Ra. The uranium concentration range from below 0.5 mBq/L to 75 mBq/L for 238U and to 300 mBq/L for 234U. In some waters the uranium activity ratio (234U/238U) is very high. The tritium concentrations are below 1.1 UT, d18O range from -10.9‰ to -7.8‰ and d2H from -84‰ to -59.4‰. These values indicate that groundwaters are dominated by components which were recharged during the Holocene. Due to the presence of specific elements such as iron, bromine and radon, as well as hydrogen sulfide, some mineral waters are classified as therapeutic.
EN
Different diagenetic environments have been recognized in the Early Miocene carbonate platform of Musayr Formation in the Red Sea rift area. Early marine diagenesis includes micritisation that occurs as thin envelope around skeletal and non-skeletal grains in low-energy mud dominated facies and isopachous fibrous calcite in high-energy grain-dominated facies. Pervasive meteoric water diagenesis resulted in cementation of the carbonates by coarse-crystalline blocky-drusy calcite and meniscus cements. Depletion of oxygen (avg. –9.08‰), carbon (avg. –1.6‰) isotopes and trace elements concentrations (avg. values of Fe: 1387 ppm; Mn: 1444 ppm; Sr: 419 ppm; Na: 1194 ppm) in conjunction with negative correlation between Mn2+ and oxygen isotope data suggest variable degrees of fluid-rock interactions and pervasive meteoric diagenesis. The formation of meteoric diagenesis in the Musayr Formation can be explained by two subsequent mechanisms: (1) the presence of meteoric lenses during the time of deposition might have been associated with active freshwater input from the hinterland (NE) due to fall in the relative sea level; (2) later uplift episode during Plio-Pleistocene may have also contributed to the pervasive meteoric diagenetic alterations of the carbonates of the Musayr Formation. The first mechanism is supported by the cement stratigraphy where the blocky-drusy cements postdate the meniscus cement. The latter mechanism seems to have more pronounced effect on the alteration of Musayr carbonate sequence by observing the occurence of late cements such as blocky calcite in most of the samples. The impact of meteoric diagenesis on the studied samples suggest that dissolution is less severe than cementation, hence the visible porosity is very low. Understanding the timing of meteoric diagenesis provides useful information about the reservoir quality distribution in syn-rift carbonate sequences.
EN
The main aims of these studies were dendrochronological and mass spectrometric analysis of the impact of climate on tree rings width and stable isotopes composition in pine (Pinus sylvestris L.). The conifers were growing in the vicinity of chemical and nitrogen factories in Kędzierzyn-Koźle (Poland) in the period of time from 1920s to 2012 AD. The combined usage of tree ring width and isotopic composition data provides historic records of the environment changes. These data allows identifying the behavior adaptation of pine growing under pollution stress to climate changes. The incremental rhythm of the studied pine populations was not identical, probably due to their different sensitivities to some climatic factors. This study evidences that the isotopic records in tree-rings α-cellulose may be sensitive bio-indicators of the way that the components of air and water may be changed by the trees in response to the climate changes and anthropogenic effects. The water use efficiency may be strongly correlated with variability of the surface temperature that may be due to increase of CO2 emission.
PL
W osadach dennych zbiorników wodnych gromadzi się materia organiczna pochodzenia autochtonicznego i allochtonicznego. Pochodzenie materii organicznej można opisać za pomocą wskaźników, do których należą: skład izotopowy węgla δ13C i azotu δ15N, iloraz C:N, biomarkery lipidowe oraz pigmenty roślinne. Izotopy węgla i azotu występują powszechnie w środowisku w dużych ilościach. Stężenia mierzonych izotopów można opisać za pomocą delty (δ), wyrażanej w promilach [‰]. Materia organiczna pochodzenia lądowego jest zubożona w izotop 13C w porównaniu do materii organicznej pochodzenia autochtonicznego. Wskaźnik δ13C ulega zmianie podczas sedymentacji, mineralizacji oraz transformacji materii organicznej w środowisku wodnym. Natomiast wartość δ15N zmienia się w zależności od przebiegu procesów denitryfikacji i odgazowania amoniaku. Materia organiczna jest również zróżnicowana pod względem stosunku C:N, gdzie dla autochtonicznej materii organicznej osiąga wartości mniejsze w porównaniu do materii pochodzenia allochtonicznego. Z kolei biomarkery lipidowe stanowią ważną grupę związków uznawanych za substancje wskaźnikowe, gdyż nie ulegają przeobrażeniom na przestrzeni lat. Stąd też wykorzystuje się je w badaniach ekologicznych i paleoekologicznych. Podobne właściwości wykazuje kolejna grupa biomarkerów, do której należą pigmenty roślinne. Dzielą się na trzy rodzaje: chlorofile, karotenoidy i fikobiliny. Analiza zawartości i składu materii organicznej w osadach dennych zbiorników wodnych za pomocą wskaźników jest skuteczną metodą pozwalającą na ocenę pochodzenia materii organicznej oraz produktywności biologicznej akwenów. Na podstawie wielkości rozkładu i stopnia zachowania wskaźników w osadach można wyznaczyć warunki środowiskowe panujące w zbiornikach wodnych w przeszłości. W artykule scharakteryzowano poszczególne wskaźniki pochodzenia materii organicznej i możliwości interpretacji w badaniach zbiorników wodnych.
EN
Autochthonous and allochthonous organic matter is accumulated in sediments of water reservoirs. Organic matter can be described as indicators, such as: isotopic signatures of δ13C and δ15N, C:N ratio, lipid biomarkers and plant pigments. A large amount of carbon and nitrogen isotopes widely occur in the environment. Concentrations of the measured isotopes can be described with δ delta, expressed in ‰. Allochthonous organic matter is depleted in 13C isotope in comparison to autochtchonous organic matter. δ15N value changes according to denitrification process and ammonia degasification. Organic matter is also diverse in terms of C:N ratio and for autochthonous organic matter achieves values less than for allochthonous organic matter. Lipid biomarkers form an important group of compounds which are considered as indicators, because they do not undergo any transformation over the years. Thus they are used in ecological and paleoecological research. Another group of biomarkers to which plant pigments belongs has similar properties. Plant pigments are divided into three types: chlorophylls, carotenoids and phycobilins. Organic matter content and composition analysis in sediments of water reservoirs with indicators is an effective method which allows to assess organic matter origin and biological productivity of water reservoirs. On the basis of decomposition level and degree of conservation of indicators in sediments we can determine environmental conditions in water reservoirs in the past. In this scientific paper, particular indicators of organic matter origin and possibilities of interpretation in water ecosystem research were characterized.
EN
A high-resolution latest Early Campanian to Early Maastrichtian carbon and oxygen stable isotope record from the northern German Boreal shelf sea based on 537 analyses of co-occurring belemnites, brachiopods, inoceramids, oysters, and bulk rock samples is presented. All samples are precisely related to their stratigraphic, systematic and facies backgrounds and form an integrated, nearly 10-myr-long dataset with considerable palaeoenvironmental and palaeoceanographical implications. Petrographic studies indicate that low-magnesium calcitic coccoliths and calcispheres (i.e., planktic carbonate) predominate the bulk-rock data (marl-limestone rhythmites and chalks), thus representing a sea-surface water signal, and that only minor diagenetic alteration of the carbonate muds took place. Based on TL and CL microscopy, the investigated belemnites are extraordinarily well preserved, which may in part be explained by their early diagenetic surficial silicification (container effect), while the other macroinvertebrate groups are all less well preserved. The (plankton-dominated) δ13C values of the marl-limestone rhythmites and chalks (+1.1 to +2.5‰), recording a surface water signal, compare well with the δ13C data of inoceramids while δ13C brach.values (+1.5 to +3.0‰) are heavier than the bulk rock data. The large variation in the δ13Cbel. (-0.1 to +3.6‰) is attributed to isotopic disequilibrium of the biogenic carbonate formed by the belemnite animal. The bulk rock δ18O values show a remarkable low scatter, supporting petrographic observation of only minor diagenetic stabilisation/cementation, and can be approximated with northern German shelf sea-surface temperatures of ca. 20°C for the Late Campanian (ca. -2‰ δ18O), being slightly cooler during the Early Maastrichtian. The δ18O values of the belemnite rostra are even less variable and quite rich in heavier 18O (-0.7 to +0.6 with a mean of -0.1‰ δ18Obel.) in comparison to bulk rock and other skeletal components. Based on their excellent microstructural preservation and non-luminescence, we conclude that the belemnite rostra are diagenetically unaltered and have preserved the primary δ18O signal of ambient seawater (12±2°C). In the absence of any indication for migration from cooler water masses and evidence for authochtonous populations we assume that the belemnites of the genera Belemnitella and Belemnella lived as nektobenthos near the sea-floor and thus record the temperature of the bottom mixed layer of the seasonally weakly stratified north German shelf sea at water depths of 100 to 150 m; the temperature gradient was thus 12.5–18.75 m/1°C. A conspicuous latest Campanian cooling event is evident in both sea-surface and bottom-water temperatures. The δ18O values of nearly all investigated benthic fossils lie between the isotope values of pristine belemnites and bulk rock, and, therefore, should be used for palaeotemperature reconstructions only with great care.
EN
We present the results of isotope measurements (δ18O, δ D, δ13CDIC and 14C) and chemical analyses (TDS, TOC, HCO3–, SO42–, Cl–, NO3–, NH4+, Ca2+, Mg2+ Na+ and K+) conducted on groundwater samples collected from deep Cenozoic aquifers. These aquifers are the basic source of drinking water at numerous localities within the study area in northern Poland. Most of the δ18O determinations are characterised by low variability (i.e., > 70 per cent of δ18O are between –9.5‰ and –9.2‰). In most cases tritium activity was not detected or its content slightly exceeded the uncertainty of measurement (from ±0.3 T.U. to ± 0.5 T.U.). On average, 14C activity is twice higher than that under similar conditions and in hydrogeological systems. The δ13CDIC values fall within the –13.6‰ to –12.8‰ range. A slight variability is observed when considering all isotope and chemical data within the study area and under these hydrogeological conditions. In general, the results of isotope and chemical analyses seem to be homogeneous, indicating the presence of closely similar groundwaters in the system, irrespective of geological formation. It is likely that there is a significant hydraulic connection between shallow and deep aquifers in the Gwda catchment, which indicates the potential for seepage of pollutants from shallow Pleistocene to deep Miocene aquifers. This can endanger the latter by e.g., high concentrations of NO3–, SO42– and Cl– ions from shallow aquifers within the Gwda catchment.
EN
Time series of investigations of selected mineral waters in the Piwniczna Spa prove the occurrence of progressive negative changes indicated by results of tritium concentration and chemical composition measurements. In some boreholes a systematic decrease of mineralization in time is observed – sometime taking the form of a drastic disappearance. According to available data this is caused by the opening of new migration paths for gaseous geogenic CO2 and, increased inflow of modern (tritium containing) waters to several wells. The latter possibility is especially visible in a case of P-5 and P-6 boreholes. Based on analytical results the necessity of regular observations of selected boreholes is postulated.
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