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EN
Lignin oxidation products (vanillyl, syringil and cummaryl phenols), and δ13C were measured in a variety of land and marine samples collected in Inner Puck Bay – dominated by marine vascular plants, small river run-off, and shallow bottom, and in Gdańsk Bay – characterized by large river run-off, small marine vascular plants population, and the average depth exceeding euphotic zone. Both study areas are parts of the Gdańsk Basin, Southern Baltic. Typical δ13C values (δ13C  = -28‰) and both composition and concentrations of lignin phenols were measured in samples originating from land. Small, yet easily measurable amounts of lignin phenols were found in marine vascular plants biomass (Σ8 = 90 µg/100 mg organic matter). The biomass was characterized by exceptionally high δ13C values (-12‰). No lignin phenols and typical δ13C values (-22‰) were measured in marine phytoplankton biomass. δ13C and both composition and content of lignin phenols in organic matter of surface sediments collected in the study area fall in the range marked by the end members. The proportion of land derived organic matter calculated using lignin phenols, or δ13C in Gdańsk Bay were comparable, while in Puck Bay they differed substantially. It was concluded that a) in areas with substantial bottom coverage with vascular plants the two end members approach, usually employed to establish the contribution of organic matter sources, is insufficient, b) organic matter originating from three sources: riverine, phytoplankton, and vascular plants contribute to sedimentary organic matter in Puck Bay with the respective proportion 30:40:30.
EN
Scots pine (Pinus sylvestris L.) growing in 16 sites in three industrial regions in Poland was analysed to delineate dendroclimatologically uniform areas. A dendrochronological and mass spectrometric analysis revealed the following: a dry and sunny previous September, low winter temperature, and moisture supply in July limit the radial growth of the pines in all the regions. The weather conditions of the current growing season have been the most strongly reflected in the isotopic ratio. Positive relationships were noted between δ13C and temperature and δ13C and sunshine. A negative relationship was observed between δ13C and precipitation and δ13C and humidity. At the same time, a positive relationship was noted between δ18O and sunshine and δ18O and temperature, but negative between δ18O and humidity. The climate signal recorded in the stable isotope composition was temporally unstable and only for a few of the climatic parameters did we find temporally stable climate signals. However, variability in the strength and direction of the relationships between variables has been observed. In general, the weather in July and August is important for determining the δ13C and δ18O signals. Instability can reflect the physiological adaptation of the plants to changes in the ecosystem.
EN
In this paper, the genesis of carbonates in a shallow, polymictic and eutrophic coastal lake (Lake Sarbsko, Poland) is deciphered. Emphasis is placed upon the relationship between carbonate sedimentation and microbial degradation of organic matter, as well as on vertical mixing of sediments. The cycling of carbonates in the lake was investigated through the analysis of lake water chemistry (pH, Ca2+, Mg2+, alkalinity, SIcalc) and the stable carbon isotope composition of dissolved inorganic carbon and sedimentary calcite. It is shown that the calcite is precipitated within a relatively short time owing to the coincidence between the activity of photosynthesizing phytoplankton, the microbial decomposition of organic matter, and the physical mixing of lake deposits. In turn, the precipitated calcite is prone to dissolution within the sediments. The data presented in this paper can be applied to explain the processes affecting the carbonate saturation in freshwater systems and to interpret δ13C signatures in the sediments of shallow lakes.
EN
Lopushna oil field has been discovered in Mesozoic-Paleogene strata of the platform basement under the Ukrainian Outer (Flysch) Carpathians. Oils from two main accumulations, occurring in the Upper Cretaceous sandstone and Upper Jurassic limestone reservoirs, have been analysed in order to identify their origin and relation to the known petroleum systems in the region of the Outer Carpathians and the basement of the Carpathian Foredeep. Results of geochemical investigations of oils, including biomarker and isotopic data, show a good correlation with oils, accumulated in the Carpathian flysch strata. Oils are low-sulphur and did not undergo significant degradation. They were generated from Type II or II/III kerogen, deposited in anoxic environments in clastic sediments. Generation occurred at the peak of “oil window”, probably in the temperature range of 122 to 126oC. The presence of oleanane indicates the Cretaceous or younger source rocks. Good correlation on biomarker and isotopic data with the organic matter dispersed in Oligocene Menilite Beds, occurring at the top of the Carpathian flysch succession, allowed authors to identify them as source rocks for oils of the Lopushna field, which thus can be regarded as an oil family of the Outer Carpathians. The migration distance for both Lopushna oils and oils accumulated in the Carpathian flysch strata was similar. A number of sub-vertical dislocations, on which the subsided flysch strata occur at the same depth level with the Jurassic and Cretaceous rocks of the platform, can be assumed as possible migration pathways from the mature source rocks of the Oligocene Menilite Beds of Boryslav-Pokuttya, Skyba or Krosno units to the Lopushna type traps, which suggests the possibility of existence of other hydrocarbon accumulations of this type. The Lopushna field so far is unique containing this type of oil found in the basement of the Ukrainian Carpathian Foredeep.
EN
Three Neogene sedimentary formations reflecting different depositional environments have been investigated for the purpose of diagnosing the isotopic source of the sedimentary organic matter and their palaeoenvironmental significance in discriminating between marine and terrestrial environments. One of these formations is composed of carbonate and marl of a shallow-marine environment (Euphrates Formation), and the other formations are composed of a clastic terrestrial (fluviatile) deposits with some differences in the depositional conditions (Injana and Dibdibba formations). The isotopic δ13C%, δ15N% values, organic carbon (OC) and total nitrogen contents, and atomic C/N ratios are used as evidence of depositional environment. Average δ13C values (in ‰) for the Dibdiba, Injana and Euphrates formations are –25.4, –25.7 and –24.5, respectively; average δ15N values (in ‰) are 4.44, 5.24 and 7.24 and average OC (in wt.%) is 0.13, 0.3 and 1.1, respectively. A significant variation in the stable carbon and nitrogen isotope compositions between fluvial and marine deposits was recorded. The δC, δ15N and C/N values indicate that the organic matter in the Euphrates Formation is of marine origin, whereas it is of terrestrial origin (fluviatile) in the Injana and Dibdibba formations. The C/Natomic values are mostly high in the Injana (37) and Dibddiba formations (51), suggesting greater input and/or preservation of terrestrial organic matter derived from land plants; the shallow-marine environment (Euphrates Formation) was characterized by a low C/N ratio (9) due to the algal-derived organic matter with limited input of terrestrial organic matter.
6
Content available remote Stable carbon isotope analysis of subfossil wood from Austrian Alps
EN
The presented studies were carried out in order to check the usefulness of subfossil wood for stable isotope analysis. The aim of research was also to define the optimal method of subfossil samples preparation. Subfossil samples used during the presented studies are a part of the multicentury dendrochronological scale. This chronology originates in an area situated around a small mountain lake — Schwarzersee, in Austria. The obtained results of stable carbon isotope measurements confirmed that the method of α-cellulose extraction by the application of acidic sodium chlorite and sodium hydroxide solutions removes resins and other mobile compounds from wood. Therefore, in the case of the analysed samples, the additional chemical process of extractives removing was found to be unnecessary. Studied wood samples contained an adequate proportion of α-cellulose similar to the values characteristic for the contemporary trees. This proved an adequate wood preservation which is essential for the conduction of isotopic research.
EN
Geochemical characteristics of 25 oils collected from Skiba Unit of the Outer Carpathians, Boryslav-Pokuttya Unit of the Carpathian Foredeep and their Mesozoic basement in the western Ukraine are presented in the paper. The first recognised oil family consists of almost all oils accumulated in the flysch sequence of the Outer Carpathians and the Carpathian Foredeep which have very similar geochemical characteristics. These oils were generated from Type II or II/III kerogen deposited in clastic sediments. They are low-sulphur and migrated short distances. Slight biodegradation processes are visible only in oils accumulated in shallow deposits in the Skiba Unit. Their source rocks are the Oligocene Menilite Shales from the Boryslav-Pokuttya Unit. Oils from the Kokhanivka and Orkhovychi deposits (the Mesozoic basement of the Carpathian Foredeep) constitute the second family. These oils are extremely heavy, high-sulphur and were generated from high-sulphur Type IIS kerogen deposited in the carbonate environment. The most probable source rocks for these oils are the Upper Jurassic strata. Oil collected from the Vola Blazhivska deposit (the Boryslav-Pokuttya Unit) shows intermediate parameters between the oil families described above. It is characterized by the presence of oleanane and high sulphur content. It was generated from the Menilite Shales containing high-sulphur kerogen. All oils were generated at an early stage or the peak of oil window.
EN
Organic carbon deposited in marine sediments is an important part of the global carbon cycle. The knowledge concerning the role of shelf seas (including the Baltic Sea) in the carbon cycle has increased substantially, however organic carbon accumulation rates in the Baltic sediments still require clarification. This paper describes methods used for assessing organic carbon and nitrogen accumulation rates in six sediment cores collected in the sediment accumulation areas in the Baltic Sea. Mass sediment accumulation rates were based on 210Pb method validated by 137Cs measurements. The organic carbon accumulation rates ranged from 18 to 75 gźCźm-2źyr-1. The C/N ratios and δ13C were used to access sedimentary organic matter provenance. The C/N ratios in the investigated cores vary in the range from 7.4 to 9.6, while δ13C ranged from -24.4‰ to -26.4‰. Results of the terrestrial organic matter contribution in the sedimentary organic matter were calculated basing on δ13C using the end member approach. Large proportion (41-73%) of the sedimentary organic carbon originates on land. The obtained results indicate the Baltic Sea sediments as an important sink for organic carbon. Substantial fraction of the sedimentary load originates on land.
EN
Methane concentrations in natural gases accumulated in the Lower and Upper Badenian and Lower Sarmatian reservoirs of the Bilche-Volytsia Unit in the western part of the Ukrainian Carpathian Foredeep usually exceed 96 vol%. Methane was generated by microbial reduction of carbon dioxide in the marine environment. Microbial methane and ethane were produced mainly during sedimentation of Miocene clays and muds. It is possible that this microbial process continues today. Higher light hydrocarbons (ethane in part, and mainly propane, butanes and pentanes) were generated during the diagenesis and the initial stage of the low-temperature, thermogenic processes from Type III and III/II kerogen deposited in Miocene strata and/or Middle and Upper Jurassic basement rocks. Limited variations in the values of geochemical hydrocarbon indices and stable isotope ratios of methane, ethane and propane with the depth indicate similar gas generation conditions within the whole Miocene succession. The microbial gases (methane and partly ethane) generated during microbial processes within the Miocene strata later migrated to the Upper Jurassic and the Upper Cretaceous (Cenomanian) reservoirs of the Mesozoic basement, and to the bottommost Lower Badenian reservoirs of the analysed Letnia, Orkhovychi, Rudky and Vereshchytsia fields. The low hydrogen concentrations within the Miocene strata as well as within the Upper Jurassic and the Upper Cretaceous (Cenomanian) reservoirs of the Mesozoic basement, and within the bottommost Lower Badenian reservoirs are also related to microbial processes. Carbon dioxide and nitrogen, which are common minor constituents, were generated by both microbial and low-temperature thermogenic processes. Moreover, CO2 also underwent secondary processes, mainly dissolution in water, during migration. At least part of the nitrogen accumulated in the Rudky field, which is remarkably high in N2 (96.9 vol%), is probably of atmospheric origin and was introduced to the reservoir by secondary recovery methods.
EN
Methane concentrations in natural gases accumulated in the autochthonous Miocene strata of the Polish Carpathian Foredeep (between Kraków and Przemyśl) usually exceeded 90 vol%. Methane and part of the ethane were generated during microbial reduction of carbon dioxide in the marine environment, mainly during the sedimentation of Miocene clays and muds. It is possible that this microbial process has continued even recently. Higher light hydrocarbons (mainly propane, butanes and pentanes) were generated during the diagenesis and the initial stage of the low-temperature thermogenic process. Very small changes in the values of geochemical hydrocarbon indices and stable isotope ratios of methane, ethane and propane with depth are evidence for similar gas generation conditions within the whole Badenian and Lower Sarmatian successions. Only in a few natural gas accumulations within the Upper Badenian and Lower Sarmatian reservoirs are thermogenic gases or thermogenic components present, both generated from mixed, type III/II kerogen. These thermogenic gases, now accumulated mainly in the bottom part of Miocene strata, probably resulted from thermogenic processes in the Palaeozoic– Mesozoic basement and then migrated to the Miocene strata along the fault zones. The presence of low hydrogen concentrations (from 0.00 to 0.26 vol%) within the Miocene strata is related to recent microbial processes. Carbon dioxide and nitrogen, which are common minor constituents, were generated in both microbial and low-temperature thermogenic processes. However, CO2 has also undergone secondary processes, mainly dissolution in water during migration. Hydrogen sulphide, which occurs in natural gases of Lower Badenian strata, was most probably generated during microbial sulphate reduction of the Lower Badenian gypsum and anhydrites.
EN
Petroleum geochemical data of 34 oils and condensates accumulated in the Carpathian Foredeep and its Mesozoic and Palaeozoic basement were used to assess their origin and genetic type. The analysed liquid hydrocarbons are characterized by variable densities and sulphur contents. No relationship between these parameters and the reservoir rock age has been found. Secondary processes of evaporative fractionation and biodegradation are evidenced for some oils. These processes proceeded most intensively on the oil from Góra Ropczycka-1K well. The oils from Opaka-1, Lubaczów-157 and Góra Ropczycka-1K wells were generated from organic matter deposited in the Upper Jurassic carbonates. The oil from the inflow in Załazie-2 well originated from the Cambrian strata, but also contains biomarkers characteristic of Miocene strata. The next family, genetically connected with the Silurian and Ordovician source rocks, consists of oils accumulated in the Lower Carboniferous carbonates in Nosówka deposit and in the Upper Jurassic in the inflow into Łękawica-1 well. The condensates collected from the Miocene (Łękawica-1, Pilzno-37, Tarnów-39 and -45 wells) and Upper Jurassic strata (Łąkta-27 and Tarnów-5 wells) were generated by organic matter dispersed in the Middle Jurassic or Lower Carboniferous clastic facies. The remaining oils, from Grobla-Pławowice, Wierzchosławice, Jastrząbka Stara, Partynia-Podborze, Dąbrowa Tarnowska, Brzezówka and Zagorzyce deposits, and the inflows into Tarnów-47 and Pilzno-12 wells were generated from kerogen enriched in organic sulphur usually dispersed in carbonate rocks. Such a type of sediments occurs in the Devonian and Lower Carboniferous strata. Also, these strata as well as the underlying Silurian rocks have sufficient maturity for generation of the discussed oils. The oleanane in the discussed oils most probably originates from kerogen of the Upper Cretaceous or Miocene strata, through which these oils migrated and eluted this biomarker.
EN
The quantity, genetic type and maturity of organic matter dispersed in Ordovician, Silurian, Devonian and Lower Carboniferous strata in the basement of the Carpathian Foredeep between Kraków and Rzeszów were determined based on the results of organic geochemical analyses of 600 rock samples collected from 44 wells. The best source rocks were found in the Silurian strata where the total organic carbon (TOC) content is up to 6.6 wt% and the median value equals ca. 1.5 wt%. The median values of the initial organic carbon contents in individual wells vary from 1.2 to 3.5 wt%. The Ordovician, Lower Devonian and clastic facies of the Lower Carboniferous strata can be considered as an additional source of hydrocarbons with the median TOC values of 0.27, 0.56 and 0.53 wt%, respectively. The Middle and Upper Devonian strata as well as the carbonate facies of the Lower Carboniferous strata have much lower quantities of organic carbon, although in these strata levels with elevated TOC contents were observed. In the Lower Palaeozoic and Lower Devonian strata, the oil-prone, low-sulphur Type II kerogen is present, whereas in the younger divisions presence of the gas-prone Type III kerogen is visible. In the Lower Carboniferous clastics gas-prone kerogen dominates. The Silurian and clastic facies of the Lower Carboniferous strata have been deposited in the normal marine conditions, whereas the Ordovician, Devonian and carbonate facies of the Lower Carboniferous strata usually experienced reducing conditions. The source rocks are mostly at the initial and middle phase of the low-temperature thermogenic processes. Locally, immature (in the Lower Carboniferous carbonates in the vicinity of Łąkta gas-condensate field) or late-mature (in the Middle and Upper Devonian strata in the area of Grobla–Pławowice oil field) source rocks were observed.
EN
We have examined 21 samples of crude oils accumulated in the Middle Cambrian sandstone reservoirs from the Polish part of the Baltic region. All the crude oils have similar parameters and indices, which suggests generation from the same source rock. Evaporative fractionation and biodegradation processes were detected in oil collected from the B4-N1/01 borehole. All crude oils have high gravities and low-sulphur contents, less than 0.3 wt.%, which suggests that their source rock contained low-sulphur kerogen deposited in a clastic environment. A low asphaltenes content (below 0.3 wt.%) and high saturate/aromatic hydrocarbon ratios indicate long migration distances or high thermal maturities. The longest migration distance was probably attained by oils from the arnowiec and B16 deposits. The biomarker data indicate an algal origin for the source organic matter deposited under conditions of clastic sedimentation. The stable carbon isotope data support this observation. The maturity of the oils analysed varies from ca. 0.75 to ca. 1.05% on the vitrinite reflectance scale. Unlike the B6, B16, Dbki and arnowiec accumulations, oils from the B3 and B4 accumulations reveal the lowest maturity.
EN
A surface geochemical survey was carried out in an abandoned ozokerite mine in Starunia, where remnants of a mammoth and three woolly rhinoceroses and one almost completely preserved rhinoceros carcass were found in 1907 and 1929. In total, 689 measurement sites were defined within the selected 300×350 m rectangle (ca. 10.5 ha). The analysed soil gases vary in their molecular and isotopic compositions. Several zones with anomalous methane concentrations over 10 vol% were identified in the study area. These anomalous concentrations correlate well with total C2-C5 alkane anomalies (over 1 vol%). The zones with carbon dioxide concentrations over 15 vol% are generally shifted SW of those, where the methane and the sum of C2-C5 alkanes anomalies were identified. High helium concentrations of crustal origin (over 0.001 vol%) are clustered near fault zones. In a majority of cases methane is of thermogenic origin, migrating to the near-surface zone from deep-seated accumulations. Microbial methane, or methane with a high microbial component, is genetically related to recent swamps. The high variability of concentrations of gaseous components together with the highly variable isotopic composition of individual gases in the soil, indicate their thermogenic and/or microbial origin, and point to the lithological diversity of Quaternary sediments in the study area. Several zones with thermogenic gaseous hydrocarbons and helium were delineated. It is likely that during the Pleistocene winters, under a thick ice and snow cover, the tundra lake and swamp zones around outflows of brines, oil, helium and thermogenic gases had a higher temperature, which resulted in melting and cracking of the ice cover. These sites would be more prospective for future search of well-preserved large vertebrates.
EN
Near-surface gases were investigated in Starunia, where remains of mammoth and woolly rhinoceroses were discovered at the beginning of the 20th century. Samples were collected at 30 measurement sites, from 0.8, 1.6, 2.4, 3.2 and 4.0 m depths and analysed for their molecular and isotopic compositions. Most of the methane and all higher gaseous hydrocarbons accumulated within the near-surface zone are of thermogenic origin. The distribution of thermogenic methane and higher gaseous hydrocarbons in Quaternary sediments is variable and, generally, increases with depth. Microbial methane or a mixture of microbial and thermogenic methane also occurs at the near-surface zone. The presence of hydrogen and alkenes in the near-surface gases also suggests a contribution from recent, microbial processes. Helium of crustal origin migrated through the Rinne Fault and other tectonic zones located in the study area, and was subsequently dispersed during migration through the lithologically diversified Pleistocene and Holocene sediments. The high variability of the carbon dioxide concentration and stable carbon isotope composition at various depths in the near-surface zone is caused by its polygenetic origin (thermogenic, microbial, and oxidation of hydrocarbons and Quaternary organic matter), and also by its dissolution in water and oil during migration through lithologically diversified Pleistocene and Holocene sediments. Zones of thermogenic methane occurrence within Pleistocene sediments, dominated by muds saturated with bitumen and brines, provide the most favourable environment for preservation of large extinct mammals. It is likely that during the Pleistocene winters, when thick ice and snow covered the tundra lake and swamp, zones of outflow of brines, oils, helium, and thermogenic gaseous hydrocarbons had a higher temperature, which could have resulted in melting and cracking of the ice cover and drowning of large mammals. The most favourable conditions for preservation of large, extinct mammals probably still exists in the vicinity of sampling probe sites Nos 21, 22, 23 and 36. Zones of dominance of microbial methane concentrations are less favourable sites for preservation of extinct mammals, because this methane was generated within recent swamps and also within recent descending meteoric waters which infiltrated into Pleistocene and Holocene sediments. Older Pleistocene microbial gases have already escaped to the atmosphere.
EN
Biological markers and stable carbon isotopic compositions of bitumen impregnating the Pleistocene and Holocene sediments around the Starunia palaeontological site (Carpathian region, Ukraine) near discovered remnants of a mammoth and three woolly rhinoceroses, and one almost completely preserved rhinoceros carcass found in 1907 and 1929, were investigated. The research was carried out to assess genetic connections between the bitumen and oils from the nearby deep accumulations of the Boryslav-Pokuttya and Skyba units of the Carpathians. Another aim of these geochemical studies was to reveal the secondary geochemical processes (oxidation and biodegradation) influencing the bitumen, and to determine which environments have been favourable or unfavourable for the preservation of large Pleistocene vertebrates. Bitumen included within the near-surface rocks are not genetically connected with residual organic matter present in Quaternary sediments. Geochemical features, such as distributions of pentacyclic triterpanes and steranes, biomarker parameters and isotope composition indicate that all bitumens originate from oil-prone, Type II kerogen with insignificant admixture of terrestrial Type III kerogen in the middle stage of catagenesis. The oils occurring in deep accumulations in the Starunia area were the sole source of bitumen found in the near-surface sediments. Input of immature organic matter to bitumen from Pleistocene and Holocene sediments has not been found. The main factors differentiating the bitumen were: biodegradation, water washing and/or weathering. Additional influence of transport of bitumen by brine was found. The most favourable conditions for preservation of large, extinct mammals within the Pleistocene muds exist in the vicinity of Nos 22 and 23 boreholes, where bitumen is best preserved. The worst conditions were found in the vicinity of Nos 1, 4, 4' and 15 boreholes. Intensification of biodegradation and weathering effects were followed by intensive, chaotic changes of the remnants of large Pleistocene mammals.
EN
Fluid inclusions in halite from Miocene rock salt of the Ukrainian Carpathian Foredeep Basin in locations where evaporites overlie oil and gas reservoir rocks are characterized by their high methane content and the presence of oil droplets in some of them. They are thus similar to fluid inclusions reported from geochemical aureoles around oil and gas accumulations in the Zechstein (Upper Permian) of western Poland (Kovalevych et al., 2008). Geochemical analyses of bitumen in bulk samples of rock salt (including content and distribution of n-alkanes and isoprenoids, carbon isotope ratios) suggest a varied origin: hydrocarbon extracted from halite from boreholes located in proximity (proved or assumed) of oil and gas deposits (Lopushna-7, Grynivka-525) are probably related to organic material dispersed within the rock salt itself, and those from the barren areas (Verkhniy Strutyn-29) are most probably cogenetic with oil accumulated in the deposits of the Boryslav-Pokuttya Nappe.
EN
We explored changes in growth, phenology, net CO[2] assimilation rate, water use efficiency, secondary defense compounds, substrate and foliage nutrient concentration of a degraded urban horse chestnut (Aesculus hippocastanum L.) site restored for three years using mulching (tree branches including foliage) and fertilization (primarily nitrogen addition). Prior to restoration, this site was characterized by high pH (ca. 8), low foliage and substrate N, and high Na and Cl concentration. Our data indicated that in untreated plots NaCl used for road deicing is the decisive factors that may be responsible for the decrease of foliar N concentration (via a reduction in NO[3] - uptake), for the decrease in photosynthesis (through high concentrations of Na and Cl in the leaves) and for increased senescence of the leaves. After three years of treatment, total nitrogen concentration in substrate increased by 3- to 4-fold and calcium concentration decreased by more than 50% in relation to pretreatment levels. Treatment significantly increased seed production (from less than 12 to more than 100 seeds per tree), individual leaf mass (from 1.8 to 3.3 g/leaf), CO[2] assimilation rate (by 21 to 30 %), improved leaf C:N ratio, and increased foliage life span by as much as six weeks. The beginning of leaf fall in untreated control trees started in mid-July and those of mulched and fertilized trees in late October. Applied treatment also eliminated visible symptoms of leaf damage due to high sodium and chlorine levels, indicating the possible role of other factors in the development of necroses. After three years of treatment, pH of most degraded plots declined from 8.2 to 7.8. That decline was accompanied by an increase in foliar Zn, Cu, and Pb concentration in the mulched and fertilized plants. In addition, treatment lowered foliage phenolics making these plants potentially more vulnerable to insect herbivory. Our study indicates that stable carbon isotope discriminationis of little value as an indicator of cumulative salinity and urban environment stress in A. hippocastanum due to pronounced differences in leaf phenology and ontogeny. The results of our study show that street tree recovery can take as little as two to three years after application of fertilization and mulching.
EN
The distribution of stable isotopes (18O and 13C) and radiocarbon in organic materials, carbonates and water samples collected from the environment of lacustrine sediments in Gościąż Lake (Central Poland) and Wigry Lake (NE Poland) were investigated. The oxygen and carbon isotopic analysis of terrestrial semi submerged and submerged plants, shells and water samples were compared with the results of the uppermost sediments from lakes. It was found that the concentration of isotopes in different components of organic and carbonate materials in lakes and their environments are reflected in isotope composition averaging of lakes sediments, whereas the isotope composition of plants and carbonate depends on biogeochemical factors. The research carried out revealed significant variations in the distribution of the stable isotopes and 14C in different elements of lacustrine ecosystem. We have analyzed mean values and variations of 14C concentration, δ18O, δ13C of plants, carbonates and the relationship between the total content of carbon and δ13C. In the case of plants, the isotope composition depends also on the physiognomy and the photosynthesis pathway. We noticed variations in δ13C and δ18O within plant tissues, variations in δ13C among whole tissue material and alphacellulose, carbon isotopic composition of photosynthetically fixed carbon and syntaxonomic dependences and then we compared the results of isotope composition of plants and carbonates in Wigry Lake and Gościąż Lake.
EN
Methane was collected from the surficial sedimentary layer (0 to about 20 cm) in 45 fresh water lakes in Poland. Sampling was also carried out at various depths of the over lying water column (0.15 to 12 m) between noon and early after noon, on a seasonal basis, between 1992 and 1996. A positive correlation between the depth of the lake water, the δ13 C (CH4) value (from ca. -l.4 to -2.3% per l m depth) and the wider δ13 C (CH4) variation over the thermocline are probably due to: the time of sinking of organic particles resulting in more in tense acetate fermentation in shallower portions of the lake; the temperature variation; differences in the precursors of methane, the diffusion effect, and an increase of bioavailable DIC (dissolved inorganic carbon) at greater depths. Non-seasonal variation of isotope ratios in methane and the depth-isotope ratio correlation show that the lake system is in dynamic equilibrium on a scale of hours and days. Therefore, earlier models of methanogenesis relating and the atmospheric methane isotopic budget, proposed by other authors and based on sampling of methane from sediments, need to be revised. More over, δ13 C (CH4) values higher during seasonal over turn (mixing of benthic and surface waters) than during stagnation, have been observed. This is probably due to the fact that during over turn periods some organic compounds (methane precursors) and methane in the surficial part of sediments, are oxidized with a resalting kinetic isotope effect. It is proposed that oxidation of methane and other organic compounds during seasonal over turn may be responsible for post-depositional lamination observed as pale (autumn over turn) and dark (summer organic-rich unoxic stagnation) millimetres-thick layers in fresh water lake sediments.
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