•Impacts of contaminated debris flow deposits on forest degradation are demonstrated.•The first combined use of dendrogeomorphic dating, wood anatomy and dendrochemistry.•Growth decline of P. abies ...is accompanied by TRDs and decreased area of ew cells.•Higher concentrations of metals in trees buried by debris flow deposits since 1995.•Increased uptake of several elements matches with the debris flow activity.
The degradation of forest ecosystems represents a severe environmental issue in anthropogenically modified landscapes worldwide. We demonstrated the negative impact of contaminated debris flow deposits on riparian forest in the Romanian Carpathians through the innovative combination of several dendroecological approaches. Reconstruction of debris flow activity using 95 individuals of Picea abies (L.) Karst. was performed to identify 11 events during the period 1952–2018. Recent events (e.g., 2007, 2014, 2016–2017) filled the valley floor after the stream was dammed in the 1980s, which deteriorated tree growth. This state was worsened by site acidity (pH = 3.8), low organic carbon, high sulfur content, and high concentrations of several metals in debris flow deposits. Wood anatomical analyses confirmed that trees producing tangential rows of traumatic resin ducts as a possible response to burial by toxic debris material subsequently produced smaller and flatter earlywood tracheids. In particular, the most obvious changes (average decrease in tracheid lumen area by 62.9% over two years) occurred after the 2016 debris flow event. Using inductively coupled plasma optical emission and/or mass spectrometry, we identified peak or increased concentrations of thallium (max. 0.7 mg kg−1), caesium (max. 0.4 mg kg−1), and aluminium (max. 434 mg kg−1) in tree biomass that could be related to debris flow activity in 1996, 2007, and 2016. Regarding the individual-specific responses of sampled trees, we conclude that the forest decline is caused by complex interaction between the depth of tree burial by debris flow deposits, the mechanical weight and chemistry of deposits, and the rate of nutrient and toxic element uptake.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Evolution of groundwater geochemistry in the Sulaimani-Warmawa Sub-basin in the Kurdistan Region of Iraq has been investigated using hydrogeochemical and isotopic methods. This is a semiarid region ...with seasonal precipitation in winter. Water chemistry generally evolves from Ca-HCO
3
groundwater type close to the basin boundaries towards Ca-Mg-HCO
3
groundwater type close to the Tanjero River along the axis of the basin. Some samples have increased concentrations of Na, Cl, and SO
4
as a consequence of dissolution of halite and gypsum embedded in carbonates. Values of pH are slightly alkaline or alkaline, and redox parameters indicate a moderately reducing environment. Isotopes δ
2
H and δ
18
O indicate recharge from winter precipitation with no evaporation. Values of dissolved
13
C(DIC) correspond to equilibrium with carbonates and C4 plants as the source of CO
2
. Values of
87
Sr/
86
Sr in groundwater are in a good agreement with carbonate dissolution as a principal process. The principal geogenic contaminant is Ba with concentrations up to 0.383 mg/L. Dissolved concentrations of other geogenic contaminants such as As, F, Mn, and Cr are low or below the detection limit as expected based on their low contents in carbonate rocks. Inverse geochemical modeling on selected profiles calibrated using δ
13
C values provided mass transfer coefficients for possible geochemical reactions. Future work should focus on interactions in the hyporheic zone of the Tanjero River.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Glacier surfaces are the most biologically productive parts of glaciers with a variety of organisms and habitats. However, distinctiveness of habitats and communities of dominant invertebrate ...consumers on the ice surface is poorly documented. We focused on dominant consumers in three supraglacial (on the glacier surface) habitats on the alpine glacier Forni – cryoconite holes (water-filled reservoirs with a thin layer of sediment at the bottom), supraglacial debris (layer of stones and gravel covering glacier surface), and surface ice of the weathering crust. We analyzed carbon and nitrogen contents and stable isotope ratios (δ
13
C, δ
15
N), organic matter (OM) content, biomass of consumers, and the community composition of consumers to investigate differences between supraglacial habitats. In cryoconite holes, tardigrades (Tardigrada) were dominant consumers. In supraglacial debris, only springtails (Collembola) occurred mainly between stones and ice. No active animals were found in the surface ice of the weathering crust. Carbon and nitrogen contents, δ
13
C, and δ
15
N of invertebrates and OM differed between habitats. Cryoconite was enriched in OM with high δ
13
C and low δ
15
N compared to supraglacial debris likely indicating differences in major components of OM serving as food of invertebrates. Also, the OM, and carbon and nitrogen contents differed between habitats with the highest concentration in cryoconite. The dry biomass of tardigrades was similar compared to springtails. We present the first observation of differences between supraglacial habitats in the Alps based on the community composition of invertebrates, OM and stable isotopes. This initial study highlights the importance of differences in habitats and its consumers in the functioning of supraglacial ecosystem.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Here, for the first time, we report the concentrations and isotopic data of Ag in a variety of ore and metallurgical samples and forest soils that have been polluted due to Ag–Pb smelter emissions. ...Similar to the Ag concentrations, we identified a large range of δ109Ag values (from −0.8 to +2.4‰), a ∼3‰ spread, within the primary and secondary materials (i.e., galena, fly ash, slag and matte). This phenomenon, however, is evidently unrelated to Ag isotopic fractionation during the smelting process, but it reflects the starting 109Ag/107Ag signal in ore mineral and/or the specific type of ore genesis. The two studied soil profiles differed in Ag isotopic composition, but on the other hand, they consistently showed significantly lighter Ag (≤+0.8‰) of metallurgical origin in the upper horizons compared to the bottom horizons and bedrocks, with low Ag amounts depleted of 107Ag (≤+2.9‰). This isotopic pattern can be attributed to a ternary mixing relationship involving two major anthropogenic Ag components and a minor contribution from geogenic Ag. Accordingly, we did not observe any post-depositional isotopic fractionation in our soils, since Ag was geochemically stable and it was not subjected to leaching. In summary, the Ag isotopes have a potential to trace variations in anthropogenic phases, to monitor specific geochemical processes, and are clearly applicable as anthropogenic Ag source and Ag load proxies.
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•Silver isotopes are applicable for anthropogenic Ag source/load tracing.•Silver isotopes have a potential to trace variations in anthropogenic phases.•Silver of metallurgical origin is geochemically stable in soils.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Climate controls forest biomass production through direct effects on cambial activity and indirectly through interactions with CO2, air pollution, and nutrient availability. The atmospheric ...concentration of CO2, sulfur and nitrogen deposition can also exert a significant indirect control on wood formation since these factors influence the stomatal regulation of transpiration and carbon uptake, that is, intrinsic water use efficiency (iWUE). Here we provide 120-year long tree-ring time series of iWUE, stem growth, climatic and combined sulfur and nitrogen (SN) deposition trends for two common tree species, Pinus sylvestris (PISY) and Picea abies (PCAB), at their lower and upper distribution margins in Central Europe. The main goals were to explain iWUE trends using theoretical scenarios including climatic and SN deposition data, and to assess the contribution of climate and iWUE to the observed growth trends. Our results showed that after a notable increase in iWUE between the 1950s and 1980s, this positive trend subsequently slowed down. The substantial rise of iWUE since the 1950s resulted from a combination of an accelerated increase in atmospheric CO2 concentrations (Ca) and a stable level of leaf intercellular CO2 (Ci). The offset of observed iWUE values above the trajectory of a constant Ci/Ca scenario was explained by trends in SN deposition (all sites) together with the variation of drought conditions (low-elevation sites only). Increasing iWUE over the 20th and 21st centuries improved tree growth at low-elevation drought-sensitive sites. In contrast, at high-elevation PCAB sites, growth was mainly stimulated by recent warming. We propose that SN pollution should be considered in order to explain the steep increase in iWUE of conifers in the 20th century throughout Central Europe and other regions with a significant SN deposition history.
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•Rising CO2 and climate warming triggered increase in water-use efficiency (iWUE).•Interactions between iWUE, N and S deposition, and tree growth were investigated.•iWUE trends were predicted by combined effects of S and N deposition and drought.•Increasing iWUE accelerated tree growth at low-elevation sites.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Rationale
Applications where stable C and O isotope compositions are useful require routine instrumental techniques with a fast sample throughput which should also produce accurate and precise ...results. We present a comparison of three different instrumental isotope ratio mass spectrometry (IRMS) approaches (Dual Inlet ‐ DI; Elemental Analyzer ‐ EA; Continuous Flow ‐ CF) to determine the stable isotope composition of carbon in carbonate matrices, with a focus on evaluating the optimum approach for less complex instrumental techniques.
Methods
The DI‐IRMS method is taken as an absolute method for obtaining accurate and precise 13C/12C ratios with internal errors usually < ±0.01‰ (2SD) and long‐term reproducibility better than ±0.03‰ (2SD). The drawbacks of DI‐IRMS are that it requires extensive offline sample preparation, rather large sample sizes (commonly >20 mg) and extended analysis times.
Results
EA‐IRMS provides rapidity of analysis, relatively non‐complex technique optimization and large sample throughput sufficient to distinguish natural trends although the larger internal errors and poorer reproducibility must be considered. The major disadvantage of EA‐IRMS lies in a constant offset of the 13C/12C ratios against DI‐IRMS, large internal errors (±0.2‰, 2SD) and the worst reproducibility (±0.3‰, 2SD) of all the explored methods. The results acquired using CF‐IRMS are comparable with those obtained by employing DI‐IRMS with an external reproducibility better than ±0.2‰ (2SD). Compared with EA‐IRMS, however, this technique requires more elaborate sample preparation – more akin to DI‐IRMS. None of these two latter techniques can provide C isotope results for coexisting phases such as calcite, dolomite and ankerite unless they are physically separated and analyzed independently.
Conclusions
All methods are appropriate for 13C/12C determinations with CF‐IRMS and EA‐IRMS less applicable to high‐precision measurements but relevant for studies requiring high sample throughput. Periodical analysis of matrix‐matched reference materials during the analytical sequence is warranted for both EA‐IRMS and CF‐IRMS.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Arctic cryoconite holes represent highly biologically active aquatic habitats on the glacier surface characterized by the dynamic nature of their formation and functioning. The most common cryoconite ...apex consumers are the cosmopolitan invertebrates – tardigrades and rotifers. Several studies have highlighted the potential relevance of tardigrades and rotifers to cryoconite holes' ecosystem functioning. However, due to the dominant occurrence of prokaryotes, these consumers are usually out of the major scope of most studies aimed at understanding biological processes on glaciers. The aim of this descriptive study is to present pioneering data on isotopic composition of tardigrades, rotifers and cryoconite from three High Arctic glaciers in Svalbard and discuss their role in a cryoconite hole trophic network. We found that tardigrades have lower δ15N values than rotifers, which indicates different food requirements or different isotopic fractionation of both consumers. The δ13C values revealed differences between consumers and organic matter in cryoconite among glaciers. However, the mechanistic explanation of these variations requires further investigation focused on the particular diet of cryoconite consumers and their isotopic ratio. Our study introduces the first observation of carbon and nitrogen stable isotopic composition of top consumers in cryoconite holes analysed by an improved method for cryoconite sample processing, paving the way for further studies of the supraglacial trophic network.
The Guacimal Pluton is situated in the Cordillera de Tilarán in the northwestern Costa Rica. It forms an oval-shaped body strongly elongated in the NW-SE direction. Its dimensions are ~15 × 4-6 km ...with an exposed surface of 60-70 km^sup 2^. The pluton intruded basic volcanic rocks of the Aguacate Group (Miocene-Pliocene) and is surrounded by a wide thermal aureole of calc-silicate metasomatic rocks. The pluton is mainly formed of monzogranites to granodiorites, which strongly prevail over more basic types occuring scarce and relatively thin dykes and enclaves. The dominant magmatic minerals of this felsic suite are quartz, plagioclase, and K-feldspar with subordinate Mg-rich biotite, amphibole I, and magnetite. Orthopyroxene, Mn-rich ilmenite. Al-poor titanite, rutile, apatite, zircon, thorite, and chalcopyrite are accessories. Secondary minerals, which occur as fillings of miarolitic cavities and interstices, are quartz II, K-feldspar II, epidote, chlorite, actinolite, ilmenite II and Al-rich titanite II. The much less frequent mafic suite (mainly quartz diorite to quartz monzodiorite/monzogabbro) is composed of plagioclase, pargasite, actinolite, K-feldspar, quartz and magnetite, with accessory amounts of opaque minerals, epidote, chlorite, and titanite. The pluton was emplaced at a depth of c. 3 km, crystallized at temperature of c. 760-800°C under a relatively high oxygen fugacity (1.6-2.1 log units above the NNO buffer). Increased activities of volatiles (H2O, F) upon cooling are indicated by the presence of highly aluminous, F-rich titanite and other hydrous silicates in miarolitic cavities. The prevailing, felsic rocks of the Guacimal Pluton are high-K calc-alkaline, whereas the mafic suite is nearly exclusively medium-K calc-alkaline in nature. Laser ablation ICP-MS dating of zircons from two granite samples yielded statistically identical U-Pb ages of 6.3 ± 0.5 and 6.0 ± 0.4 Ma, respectively. The Sr-Nd isotopic compositions are rather primitive (^sup 87^Sr/^sup 86^Sr^sub 6^ = 0.70380-0.70413, ε^sup 6^^sub Nd^ ~ +7.3 to +7.9). Narrow range of these values rules out open-system processes such as magma mixing or assimilation of isotopically contrasting upper continental crust. Instead, the felsic suite is interpreted as either having crystallized from a highly fractionated melt extracted from a plagioclase-amphibole-dominated crystal mush in a putative deep crustal reservoir or a product of partial melting of older arc-related rocks, such as intermediate lavas or volcaniclastics or immature psammitic sediments rich in volcanic material. The observed variation in the felsic suite was most likely produced by low degrees of closed-system fractional crystallization of an assemblage dominated by feldspars. At least some of the rocks of the volumetrically subordinate mafic suite may represent lithologies rich in the complementary cumulates. PUBLICATION ABSTRACT
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IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UL, UM, UPUK
The thesis is devoted to the topic of preparatory courses for applicants for foster care. The aim of the thesis is to chart the course of professional preparation of future foster parents and ...replenish their subjective opinions. The theoretical part refers to the current legislative changes affecting the area of foster care in the Czech republic. It also deals with topics closely related to foster care, such as kinship care, contact with the biological parents or the identity of children in foster care. The following section is focused on the analysis of available training programs for foster parents, their specifics and the related methodological recommendations of Ministry of Labour and Social Affairs of the Czech Republic. Practical work was supported by DC Paprsek. By the form of semi-structured interviews with applicants for foster care was studied their subjective view of the importance and effectiveness of training courses.
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