scholarly journals Variations of Isotopic Composition of Carbon in the Karst Environment from Southern Poland, Present and Past

Radiocarbon ◽  
1999 ◽  
Vol 41 (1) ◽  
pp. 81-97 ◽  
Author(s):  
Anna Pazdur ◽  
Tomasz Goslar ◽  
Mirosława Pawlyta ◽  
Helena Hercman ◽  
Michał Gradziński
Keyword(s):  
Isotopic Composition ◽  
Dissolved Inorganic Carbon ◽  
Isotope Composition ◽  
Mean Values ◽  
Calcium Carbonates ◽  
Suitable Material ◽  
Southern Poland ◽  
Karst Environment ◽  
Biogenic Carbon ◽  
Dating Methods

We describe a comprehensive study of carbon isotopes in several karst springs and their environs in a contemporary karst environment in the region of the Cracow-Wieluñ Upland and Western Tatra Mountains, Southern Poland. We collected samples of water, plants and carbonate deposited on aquatic plants, and obtained 13C values and 14C concentrations. We also investigated a group of the youngest calcium carbonates from caves where deposition is still being observed or ceased no more than a few hundred years ago. The determination of a 14C dilution factor (q) in these carbonates allows us to determine the “true” radiocarbon ages of old speleothems from caves in the area under investigation and enables the use of old speleothems as suitable material for extending the 14C calibration time scale, the “Absolute” age having been determined by U/Th or amino acid racemization (AAR) dating methods. Measurements of δ13C and 14C concentrations were made on dissolved inorganic carbon (DIC) extracted from water samples. Calculated values of q range from 0.55 to 0.68 and δ13C values range from −10% to −13% versus VPDB with mean values equal to 0.65 and −12%, respectively. Results indicate that the dissolution process of limestone bedrock is a closed system with the dominating contributor being biogenic carbon dioxide.Isotopic composition of carbon in contemporary plants collected at the karstic springs at 3 localities is highly diverse, with different species distinctly varying in both q and δ13C values. Extremely light values of 13C (under −40%), observed in Algae and Hyloconium splendens, are correlated with 14C concentrations that are much lower than 100 pMC. Small systematic changes of isotopic composition were found in plants of the same species collected along streams at various distances from the spring. The youngest calcium carbonates from different caves show a relatively high scatter of both δ13C values and 14C concentration. The lower reservoir effect for 14C is observed in samples with higher value of δ13C, indicating equilibrium conditions in the sedimentation of carbonate. Pazdur et al. (1995b) presented 14C dating results and paleoclimatic interpretation of 170 14C analyses of 89 speleothems from 41 caves obtained through 1994. Investigations continued until early 1997, during which time a speleothem, JWi2, was dated by 14C, U/Th and AAR dating methods, and its stable isotope composition (δ13C and δ18O) analyzed in detail (reported here). Carbon isotope analyses indicate very large differences among results obtained by U/Th, AAR, and 14C dating methods.

scholarly journals Seasonal variations in nitrate isotope composition of three rivers draining into the North Sea

2010 ◽  
Vol 7 (4) ◽  
pp. 6051-6088 ◽  
Author(s):  
A. Deek ◽  
K. Emeis ◽  
U. Struck
Keyword(s):  
Isotopic Composition ◽  
North Sea ◽  
Isotope Composition ◽  
Atmospheric Oxygen ◽  
Isotope Effects ◽  
Nitrate Sources ◽  
Particulate Nitrogen ◽  
Soil Nitrification ◽  
Mean Values ◽  
Δ 15N

Abstract. Nitrate loading of coastal ecosystems by rivers that drain industrialised catchments continues to be a problem in the South Eastern North Sea, in spite of significant mitigation efforts over the last 2 decades. To identify nitrate sources, sinks, and turnover in three German rivers that discharge into the German Bight, we determined δ 15N-NO3- and δ18O- NO3- in nitrate and δ 15N of particulate nitrogen for the period 2006–2009 (biweekly samples). The nitrate loads of Rhine, Weser and Ems varied seasonally in magnitude and δ 15N-NO3- (6.5–21‰), whereas the δ 18O-NO3- (-0.3–5.9‰) and δ 15N-PN (4–14‰) were less variable. Overall temporal patterns in nitrate mass fluxes and isotopic composition suggest that a combination of nitrate delivery from nitrification of soil ammonia in the catchment and assimilation of nitrate in the rivers control the isotopic composition of nitrate. Nitrification in soils as a source is indicated by low δ 18O-NO3- in winter, which traces the δ 18O of river water. Mean values of δ 18O-H2O were between –9.4‰ and –7.3‰; combined in a ratio of 2:1 with the atmospheric oxygen δ 18O of 23.5‰ agrees with the found δ 18O of nitrate in the rivers. Parallel variations of δ 15N-NO3- and δ 18O-NO3- within each individual river are caused by isotope effects associated with nitrate assimilation in the water column, the extent of which is determined by residence time in the river. Assimilation is furthermore to some extent mirrored both by the δ 15N of nitrate and particulate N. Although δ 15-NO3- observed in Rhine, Weser and Ems are reflected in high average δ 15N-PN (between 6‰ and 9‰, both are uncorrelated in the time series due to lateral and temporal mixing of PN. That a larger enrichment was consistently seen in δ 15N-NO3- relative to δ 18O-NO3- is attributed to constant additional diffuse nitrate inputs deriving from soil nitrification in the catchment area. A statistically significant inverse correlation exists between increasing δ 15N-NO3- values and decreasing NO3- concentrations. This inverse relationship – observed in each seasonal cycle – together with a robust relationship between human dominated land use and δ 15N-NO3- values demonstrates a strong influence of human activities and riverine nitrate consumption efficiency on the isotopic composition of riverine nitrate.

scholarly journals Multi-Technique groundwater flow system analysis and dating of deep aquifers in Alessandria Basin (Piedmont - IT)

2020 ◽  
Author(s):  
Nicola Quaranta ◽  
Elena Cogo ◽  
Adriano Simoni ◽  
Elisa Sacchi ◽  
Mariachiara Caschetto ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
Groundwater Flow ◽  
System Analysis ◽  
Dissolved Inorganic Carbon ◽  
Flow System ◽  
Isotope Composition ◽  
Radioactive Isotopes ◽  
Deep Groundwater ◽  
Groundwater Flow System ◽  
Deep Aquifers

The aim of the study was to set up a protection system from pollution of the deep aquifer of the Alessandria basin, by redefining the recharge areas, focused on this portion of Piedmont territory, and therefore by creating some reserve areas of deep groundwater, to be preserved for future human drinking purposes. In addition to the classical hydrodynamic and geochemical monitoring techniques, the groundwaters were analyzed with reference to a monitoring network of 25 selected wells with deep screens (80-300 m below ground surface) combining radiochemical dating (14C and δ13C of dissolved inorganic carbon - DIC) with anthropogenic tracers (CFCs, SF6) as indicators of recent recharge/ mixing. Stable isotope composition (δ2H and δ18O – H2O) was assessed during a 1-year sampling of snow-rain precipitations gauges distributed in altitude in order to define Local Meteoric Water Lines; the isotopic composition was also seasonally measured for the main rivers and in selected deep-wells. The 3D numerical model was implemented in FEflow platform and calibrated on the basis of the available monitoring data; it was used as a support tool in the delimitation of the recharge areas, starting from the analysis of the distribution of flows. This model was crucial for delimiting the “reserve areas”, since it was able to simulate groundwater flows using both purely advective transport conditions (particle tracking technique), and more realistic conditions of advective and dispersive transport, by introducing dispersive parameters and using the Life Time Expectancy (LTE) reservoir distribution. The integrated use of “traditional” techniques of regional groundwater flow system monitoring (hydrochemistry, stable isotopic composition) and of dating techniques based on radioactive isotopes and anthropogenic tracers, provided a reliable support to the validation of flow and transport simulation model, oriented to identify recharge areas and “reserve areas” of future extraction of deep groundwater for drinking purpose.

Evolution of Radiocarbon in a Sandy Aquifer Across Large Temporal and Spatial Scales: Case Study from Southern Poland

Radiocarbon ◽  
2013 ◽  
Vol 55 (2) ◽  
pp. 905-919 ◽  
Author(s):  
M Dulinski ◽  
K Rozanski ◽  
T Kuc ◽  
Z Gorczyca ◽  
J Kania ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
Unsaturated Zone ◽  
Dissolved Inorganic Carbon ◽  
Geochemical Modeling ◽  
Spatial Scales ◽  
Carbon Isotopic Composition ◽  
Pore Waters ◽  
Southern Poland ◽  
Carbon Isotopic ◽  
Sandy Aquifer

We present the results of a comprehensive study aimed at tracing the evolution of carbon isotopic composition of the TDIC (total dissolved inorganic carbon) reservoir from the unsaturated zone down to the discharge area, in a sandy aquifer near Kraków, southern Poland. A multilevel well penetrating the unsaturated zone in the study area was equipped with horizontally mounted lysimeters with ceramic suction cups to collect samples of pore water and metal probes to collect soil air. Strong seasonal fluctuations were observed of soil pCO2 extending down to the water table, coupled with distinct, well-defined depth profiles of δ13CTDIC reaching approximately −10′ at 8 m depth and almost constant radiocarbon content in the TDIC pool, comparable to 14CO2 levels in the local atmosphere. Simple models (closed/open system) do not account for the observed depth variations of carbon isotopic composition of the TDIC pool. This suggests that the TDIC reservoir of pore waters is evolving under conditions gradually changing from an open towards a closed system. In order to explain 13C and 14C content of dissolved carbonates in groundwater in the recharge area of the studied aquifer, additional sources of carbon in the system are considered, such as organic matter decomposition accompanied by reduction of dissolved nitrates and sulfates. The piston-flow l4C ages of groundwater in the confined part of the studied system were calculated using 2 approaches: 1) the correction model proposed by Fontes and Garnier (1979) was used to calculate groundwater ages, utilizing the chemical and carbon isotopic data available for the sampled wells; and 2) inverse geochemical modeling was performed for selected pairs of wells using NETHPATH code. The calculated 14C ages of groundwater range from approximately 0.6 to 37.5 ka BP. Although both methods appeared to be in a broad agreement, NETHPATH calculations revealed that isotopic exchange processes between TDIC pool and solid carbonates present in relatively small amounts in the aquifer matrix play an important role in controlling the 13C and 14C signatures of the dissolved carbonate species in groundwater and should be taken into account when 14C ages are calculated.

scholarly journals Dispersed Carbon in Basalts of the Altered Oceanic Crust: Isotope Composition and Mechanisms of Formation

Petrology ◽  
2021 ◽  
Vol 29 (6) ◽  
pp. 614-626
Author(s):  
V. B. Polyakov ◽  
S. N. Shilobreeva
Keyword(s):  
Isotopic Composition ◽  
Oceanic Crust ◽  
Elemental Carbon ◽  
Dissolved Inorganic Carbon ◽  
Isotope Composition ◽  
Adsorbed Layer ◽  
Total Carbon ◽  
Boudouard Reaction ◽  
Carbonate Phase ◽  
Basalt Glasses

Abstract Carbon contents and isotopic compositions were compared in the basalt groundmass of the oceanic crust of different age in the zone of the East Pacific Rise. In samples the basalt groundmass of the ancient oceanic crust (~270 Ma, ODP Site 801C) in which a carbonate phase was found, the isotopic composition of the oxidized carbon (δ13C = ±1.5‰) indicates that this carbon was formed by the precipitation of seawater dissolved inorganic carbon (DIC). In the samples in which no carbonate phase was identified, the low concentration (<0.1 wt % CO2) of oxidized dispersed carbon and its isotopic composition (δ13C < –7‰) are in the range of values typical of carbon dissolved in basalt glasses without crystallinity. This makes it possible to relate the oxidized dispersed carbon to residual carbon dissolved in the magmatic melt after CO2 degassing. The precipitation of DIC results in a positive correlation between the concentration of total carbon and its δ13C values, along with the formation of a carbonate phase. The application of this criterion to basalt groundmass samples of the young crust (~15 Ma, ODP Site 1256D) showed that oxidized dispersed carbon in the young oceanic crust groundmass was not formed by the precipitation of DIC, contradicting the generally accepted paradigm. Constant concentration and δ13C values of the reduced dispersed carbon in the basalt groundmass of the young and ancient oceanic crusts, including lithological zones where microbial activity has not been recorded, indicate that the most probable model is high-temperature abiogenic generation of reduced dispersed carbon near the ridge axis. The Fischer–Tropsch synthesis and/or Bell–Boudouard reaction provide a possible basis for the abiogenic model. The Bell–Boudouard reaction 2CO = C + CO2 leads to the formation of an adsorbed layer of elemental carbon on the fresh surfaces of minerals during background alteration of the oceanic basalt crust. The CO2–CO gas-phase equilibrium maintains the necessary depletion of the newly formed elemental carbon in the 13C isotope to δ13C < –20‰. Abiogenic models for the origin of the isotopically light reduced dispersed carbon in the basalt groundmass do not assume the presence of carbon depleted in the heavy 13C isotope in the magmatic melt.

Seasonal trends in the stable isotopic composition of snow and meltwater runoff in a subarctic catchment at Okstindan, Norway

2004 ◽  
Vol 35 (2) ◽  
pp. 119-137 ◽  
Author(s):  
S.D. Gurney ◽  
D.S.L. Lawrence
Keyword(s):  
Isotopic Composition ◽  
Mean Value ◽  
Mean Values ◽  
Stable Isotopic Composition ◽  
Meltwater Runoff ◽  
Stable Isotopic ◽  
The Mean ◽  
The Difference ◽  
Δ18o And Δd

Seasonal variations in the stable isotopic composition of snow and meltwater were investigated in a sub-arctic, mountainous, but non-glacial, catchment at Okstindan in northern Norway based on analyses of δ18O and δD. Samples were collected during four field periods (August 1998; April 1999; June 1999 and August 1999) at three sites lying on an altitudinal transect (740–970 m a.s.l.). Snowpack data display an increase in the mean values of δ18O (increasing from a mean value of −13.51 to −11.49‰ between April and August), as well as a decrease in variability through the melt period. Comparison with a regional meteoric water line indicates that the slope of the δ18O–δD line for the snowpacks decreases over the same period, dropping from 7.49 to approximately 6.2.This change points to the role of evaporation in snowpack ablation and is confirmed by the vertical profile of deuterium excess. Snowpack seepage data, although limited, also suggest reduced values of δD, as might be associated with local evaporation during meltwater generation. In general, meltwaters were depleted in δ18O relative to the source snowpack at the peak of the melt (June), but later in the year (August) the difference between the two was not statistically significant. The diurnal pattern of isotopic composition indicates that the most depleted meltwaters coincide with the peak in temperature and, hence, meltwater production.

Hydrogeochemical temporal variations related to changes of seismic activity at Tenerife, Canary Islands

2021 ◽  
Author(s):  
Cecilia Amonte ◽  
María Asensio-Ramos ◽  
Gladys V. Melián ◽  
Nemesio M. Pérez ◽  
Eleazar Padrón ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
Seismic Activity ◽  
Temporal Variations ◽  
Total Alkalinity ◽  
Molar Ratio ◽  
Sampling Point ◽  
Volcanic System ◽  
Mean Values ◽  
Isotopic Analyses ◽  
San Fernando

&lt;p&gt;The oceanic active volcanic island of Tenerife (2034 km&lt;sup&gt;2&lt;/sup&gt;) is the largest of the Canarian archipelago. There are more than 1,000 galleries (horizontal drillings) in the island, which are used for groundwater exploitation and allow reaching the aquifer at different depths and elevations. During a two-year period (July 2016 to July 2018), a hydrogeochemical study was carried out in two galleries on Tenerife (Fuente del Valle and San Fernando) for volcanic monitoring purposes with weekly sampling. Physicochemical parameter of water, such us temperature (&amp;#186;C), pH and electrical conductivity (E.C., &amp;#181;S&amp;#183;cm&lt;sup&gt;-1&lt;/sup&gt;), were measured in-situ at each sampling point and chemical/isotopic composition of the water determined later in the laboratory.&lt;/p&gt;&lt;p&gt;Temperature values showed mean values of 28.1 &amp;#186;C and 19.0 &amp;#186;C for Fuente del Valle and San Fernando galleries, respectively. According to the average pH values, which were 6.30 for Fuente del Valle and 7.13 for San Fernando, and based on the chemical composition, both galleries are sodium-bicarbonate (Na-HCO&lt;sub&gt;3&lt;/sub&gt;) type. E.C. values in both galleries presented high ranges, with mean values of 975 and 1648 &amp;#181;S&amp;#183;cm&lt;sup&gt;-1&lt;/sup&gt; for Fuente del Valle and San Fernando, respectively. The total alkalinity mean value of groundwater from Fuente del Valle gallery was 11.3 mEq&amp;#183;L&lt;sup&gt;-1&lt;/sup&gt; HCO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt;, while that from San Fernando was 17.3 mEq&amp;#183;L&lt;sup&gt;-1&lt;/sup&gt; HCO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt;. The SO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;2-&lt;/sup&gt;/Cl molar ratio was 0.59 and 3.4 for the samples from Fuente del Valle and San Fernando galleries, respectively.&lt;/p&gt;&lt;p&gt;The &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O and &amp;#948;D isotopic analyses showed a meteoric origin of groundwaters, with mean values of -6.2&amp;#8240; and -26&amp;#8240; vs. VSMOW for Fuente del Valle and -6.2&amp;#8240; and -21 &amp;#8240; vs. VSMOW for San Fernando. The isotopic data showed a strong interaction with endogenous gases such as CO&lt;sub&gt;2&lt;/sub&gt;, H&lt;sub&gt;2&lt;/sub&gt;S, H&lt;sub&gt;2&lt;/sub&gt;, etc. Regarding the isotopic composition of total dissolved carbon species, expressed as &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;TDIC&lt;/sub&gt;, average values of -0.17&amp;#8240; and 0.26&amp;#8240; were obtained for Fuente del Valle and San Fernando galleries, respectively. These results show an endogenous origin CO&lt;sub&gt;2&lt;/sub&gt; signature, heavier for Fuente del Valle gallery groundwater compared to that of San Fernando.&lt;/p&gt;&lt;p&gt;Groundwater physicochemical parameters exhibited stable values throughout the study period, while significant temporal variations were observed in the total alkalinity, SO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;2-&lt;/sup&gt;/Cl&lt;sup&gt;-&lt;/sup&gt; molar ratio, &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O and &amp;#948;D. Changes in isotopic ratios coincided with variations observed in the alkalinity and the SO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;2-&lt;/sup&gt;/Cl&lt;sup&gt;-&lt;/sup&gt; molar ratio. On October 2, 2016, a seismic swarm of long-period events was recorded on Tenerife followed by a general increase of the seismic activity in and around the island. A correlation was observed between some hydrogeochemical parameters in the groundwaters of the galleries, related to observed changes of the seismic activity. This study demonstrates the suitability of monitoring the chemical and isotopic composition of groundwater from Fuente del Valle and San Fernando galleries, as they are sensitive to changes in volcanic activity on Tenerife island. The study of groundwaters associated to a volcanic system can provide information about the magmatic gas input in the aquifer, modelling how the groundwaters flow through the edifice, and offer important geochemical information that could herald a future eruption.&lt;/p&gt;

scholarly journals Quantifying sea surface temperature ranges of the Arabian Sea for the past 20 000 years

2011 ◽  
Vol 7 (4) ◽  
pp. 1337-1349 ◽  
Author(s):  
G. M. Ganssen ◽  
F. J. C. Peeters ◽  
B. Metcalfe ◽  
P. Anand ◽  
S. J. A. Jung ◽  
...  
Keyword(s):  
Arabian Sea ◽  
Isotope Composition ◽  
Planktonic Foraminifera ◽  
Sediment Cores ◽  
Maximum Temperature ◽  
Physical Parameters ◽  
Seasonal Temperature ◽  
Mean Values ◽  
The Past ◽  
Temperature Ranges

Abstract. The oxygen isotopic composition of planktonic foraminifera tests is one of the widest used geochemical tools to reconstruct past changes of physical parameters of the upper ocean. It is common practice to analyze multiple individuals from a mono-specific population and assume that the outcome reflects a mean value of the environmental conditions during calcification of the analyzed individuals. Here we present the oxygen isotope composition of individual specimens of the surface-dwelling species Globigerinoides ruber and Globigerina bulloides from sediment cores in the Western Arabian Sea off Somalia, inferred as indicators of past seasonal ranges in temperature. Combining the δ18O measurements of individual specimens to obtain temperature ranges with Mg/Ca based mean calcification temperatures allows us to reconstruct temperature extrema. Our results indicate that over the past 20 kyr the seasonal temperature range has fluctuated from its present value of 16 °C to mean values of 13 °C and 11 °C for the Holocene and LGM, respectively. The data for the LGM suggest that the maximum temperature was lower, whilst minimum temperature remained approximately constant. The rather minor variability in lowest summer temperatures during the LGM suggests roughly constant summer monsoon intensity, while upwelling-induced productivity was lowered.

scholarly journals Ecosystem effects of CO<sub>2</sub> concentration: evidence from past climates

2009 ◽  
Vol 5 (2) ◽  
pp. 937-963 ◽  
Author(s):  
I. C. Prentice ◽  
S. P. Harrison
Keyword(s):  
Forest Cover ◽  
Dissolved Inorganic Carbon ◽  
Net Primary Production ◽  
Isotope Composition ◽  
Late Quaternary ◽  
Co2 Concentration ◽  
C3 Plants ◽  
Sea Level Changes ◽  
Co2 Effects ◽  
Concentration Changes

Abstract. Atmospheric CO2 concentration has varied from minima of 170–200 ppm in glacials to maxima of 280–300 ppm in the recent interglacials. Photosynthesis by C3 plants is highly sensitive to CO2 concentration variations in this range. Physiological consequences of the CO2 changes should therefore be discernible in palaeodata. Several lines of evidence support this expectation. Reduced terrestrial carbon storage during glacials, indicated by the shift in stable isotope composition of dissolved inorganic carbon in the ocean, cannot be explained by climate or sea-level changes. It is however consistent with predictions of current process-based models that propagate known physiological CO2 effects into net primary production at the ecosystem scale. Restricted forest cover during glacial periods, indicated by pollen assemblages dominated by non-arboreal taxa, cannot be reproduced accurately by palaeoclimate models unless CO2 effects on C3-C4 plant competition are also modelled. It follows that methods to reconstruct climate from palaeodata should account for CO2 concentration changes. When they do so, they yield results more consistent with palaeoclimate models. In conclusion, the palaeorecord of the Late Quaternary, interpreted with the help of climate and ecosystem models, provides evidence that CO2 effects at the ecosystem scale are neither trivial nor transient.

Status-quo of carbonate cadmium isotope compositions as a paleo-productivity proxy

2021 ◽  
Author(s):  
Simon V. Hohl
Keyword(s):  
Isotopic Composition ◽  
Isotope Composition ◽  
Status Quo ◽  
Ambient Seawater ◽  
Isotopic Compositions ◽  
Marine Carbonates ◽  
The Status ◽  
State Changes ◽  
Underlying Processes ◽  
Isotope Systematics

&lt;p&gt;Cadmium (Cd) and isotope systematics are emerging tools for studying the biogeochemical cycling of micronutrients in the oceans, and sedimentary archives, as Cd concentrations in seawater show a nutrient-like behaviour, with surface depletion and deep water enrichments. However, the underlying processes are yet to be fully understood. The Cd concentration and isotopic composition of seawater are set by the balance of Cd inputs (and their isotopic composition) and the fractionation on removal to sedimentary sinks. The most favoured explanation is the Cd utilisation by marine phototrophic biomass, causing the surface water&amp;#8217;s dissolved Cd pool depletion creating a depth gradient of increasing Cd concentrations and lighter isotopic compositions. Under incomplete oxidative recycling, organic matter may act as an effective Cd sink and authigenic minerals may store the ambient seawater&amp;#8217;s Cd isotope composition.&lt;/p&gt;&lt;p&gt;Consequently, stable Cd isotope compositions in marine carbonates show broad variations linked to paleo-productivity and redox state changes. Additional fractionation processes govern the Cd isotopic compositions of marine sediments. Besides biological utilisation, experimental Cd partitioning into authigenic calcites or sulphides under variable redox and salinity conditions has been shown. &amp;#160;Therefore, when applying Cd isotopes in carbonates, other geochemical proxies must be evaluated very carefully to understand the involved Cd fractionation processes. This presentation aims to present the status quo of research done on authigenic and biologic carbonates and carbonate leachates in carbonatic shales to show the strengths and pitfalls of this new emerging bio-geoscience isotope proxy and its use for paleoenvironmental reconstructions on Earth and beyond.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;

Trace elements and Pb isotope composition of annual tree rings and pine needles growing in highly industrialized region in southern Poland

2021 ◽  
Author(s):  
Barbara Sensuła ◽  
Nathalie Fagel
Keyword(s):  
Trace Elements ◽  
Chemical Composition ◽  
Tree Rings ◽  
Wet Deposition ◽  
Isotope Ratio ◽  
Isotope Composition ◽  
Pine Needles ◽  
Pb Isotope ◽  
Southern Poland ◽  
Icp Ms

&lt;p&gt;Trees can provide annual records of ecosystem changes connected with human activity over several decades. These changes can be recorded in the pattern of variation of tree-rings widths and in the variation in the elemental composition of wood. Analysis of trace metal pollution is based on the assumption that element concentrations in tree foliage and tree rings represent element availability in the environment.&lt;/p&gt;&lt;p&gt;We determined the chemical composition of pine needles and annual tree rings to monitor environmental contamination in an urban forest environment in the most industrialized part of southern Poland.&lt;/p&gt;&lt;p&gt;The concentrations of trace elements (Cr, Co, Ni, Cu, Zn, Pb) and the Pb isotope composition were measured in needles from&amp;#160;Pinus sylvestris&amp;#160;L. growing in nine urban forests near five factories. Trace elemental concentration and Pb isotope ratio were determined by ICP-MS and MC-ICP-MS, respectively. The needles were characterized based on the concentrations of Cr, ranging from 0.05 to 0.7 mg/kg, Co, from 0.005 to 0.075 mg/kg, Ni, from 0.12 to 0.66 mg/kg, Cu, from 0.49 to 1.0 mg/kg, Zn, from 3.9 to 14 mg/kg, and Pb, from 0.06 to 0.53 mg/kg. The&amp;#160;&lt;sup&gt;208&lt;/sup&gt;Pb/&lt;sup&gt;206&lt;/sup&gt;Pb ratio ranged from 2.08 to 2.11 and the&amp;#160;&lt;sup&gt;206&lt;/sup&gt;Pb/&lt;sup&gt;207&lt;/sup&gt;Pb ratio between 1.15 and 1.17. The heterogeneity of Pb isotope ratio indicates that there are different sources affecting the Pb isotopic composition of pine needles (Sensu&amp;#322;a et al., 2021).&lt;/p&gt;&lt;p&gt;In one of the investigated site, a radial trace-element profiles were determined by Laser Ablation Inductively Coupled Plasma-Mass Spectrometry (Laser ablation: New Wave Research UP-193 FX Fast Excimer, ICP-MS: Thermo Scientific X-Series2 with CCT -Collision Cell Technology) at Royal Museum for Central Africa (Belgium). LA-ICP-MS provides a repeatable, minimally destructive, sensitive method for determining many elements in wood tissue, with relatively high spatial resolution.Temporal variations of element concentration (median) in annual tree-rings of pines were compared with time series of wet deposition of pollutant and air pollutant concentration in the investigated area.&amp;#160;The similar trends of magnitudes changes can be observed between analysed elements concentration (Na, Mg, Fe, Ni, Zn) and total wet deposition of these elements in the environment during vegetation period or these elements concentration in the rain (Sensu&amp;#322;a et al. 2017).&amp;#160;&lt;/p&gt;&lt;p&gt;Different space-time patterns of element accumulation in pine needles and annaul tree rings were observed. The variation in isotopic composition reflects a mix between different anthropogenic sources.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;References:&lt;/p&gt;&lt;p&gt;Sensu&amp;#322;a, B., Wilczy&amp;#324;ski, S., Monin, L., Allan, M., Pazdur, A., &amp; Fagel, N. (2017). Variations of tree ring width and chemical composition of wood of pine growing in the area nearby chemical factories,&amp;#160;Geochronometria,&amp;#160;44(1), 226-239. doi:&amp;#160;https://doi.org/10.1515/geochr-2015-0064&lt;/p&gt;&lt;p&gt;Sensu&amp;#322;a, B., Fagel, N., &amp; Michczy&amp;#324;ski, A. (2021). Radiocarbon, trace elements and pb isotope composition of pine needles from a highly industrialized region in southern Poland.&amp;#160;Radiocarbon,&amp;#160;1-14. doi:10.1017/RDC.2020.132&lt;/p&gt;

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