325 research outputs found
Inferring the diet of extinct elephants: The case study of straight-tusked elephants from Neumark Nord 1 (Northeastern Germany)
Inferring the diet of fossil mammals is a major approach to mammalian palaeobiology and palaeoecology. Compared to other mammals, proboscideans pose significant problems because elephants eat different kinds of food and may change it frequently. Results obtained by analysing the last molars of Palaeoloxodon antiquus from Neumark Nord, highlight the effectiveness of a multidisciplinary approach in inferring the dietary adaptation of elephants. The microwear pattern and stable isotope data obtained for the straight-tusked elephants from Neumark Nord 1, suggest they were mainly grazers in a wooded grassland and moderately humid environment
Sulfur and oxygen isotope compositions of Upper Triassic sulfates from Northerm Apennines (Italy): palaeogeographic and hidrogeochemical implications
Upper Triassic bedded evaporite sulfate of the Burano Formation outcropping at Cerreto Pass between Tuscany and Emilia-Romagna in the Northern Apennines were analyzed for sulfur and oxygen isotope compositions, yielding d34S and d18O values of 15.5±0.4‰ and 10.8±1.2‰, respectively (mean ±99% confidence intervals). Combining these values with those of other Burano Formation sulfate deposits along the Apennine chain, mean for d34S and d18O values are obtained (15.2±0.2‰ and 10.9±0.5‰, respectively). These isotopic signatures are interpreted as preserved primary features, despite the fact that the Burano Formation underwent anchizone to epizone metamorphism during the Apennine orogenesis. An overall d18O value of 10.9±1.5‰ (mean ± pooled standard deviation), obtained by combining consistent sets of data from Italy and Spain, closely approaches that of gypsum deposited from the Tethys ocean during the Late Triassic. In addition, reviewing the isotope data published on Late Triassic evaporite sulfates from the Mediterranean area and abroad, several d34S values appear to be lower than the inferred primary isotopic signature, and seemly decrease from East to West in the Mediterranean region, suggesting a similar trend for the Tethys ocean sulfate. Possibly, 34S-depleted sulfate entered the ocean through oxidation of volcanic SO2 emitted in the atmosphere and degassed from the seafloor during the development of Late Triassic rifting. On the other hand, positive shifts of d34S and d18O values also occur, defining a common trend that may be related to synsedimentary biological effects or post-depositional metasomatic-metamorphic effects, the latter affecting particularly the d18O signature. Therefore, the d34S and d18O signatures of evaporite sulfate may provide a like “slide-rule” diagram to distinguish between isotopic effects related to biological or abiological processes, thus contributing to the reconstruction of paleoenvironments and paleogeographic settings. Based on the d34S-d18O “slide-rule”, the isotopic composition of sulfate dissolved in spring and stream waters of northern Tuscany was interpreted in terms of origin of the sulfate and modifying processes in solution. It was concluded that sulfate in springs derives from Upper Triassic evaporite existing locally at depth (Burano Formation), whereas sulfate in streams is manifestly a mixture of Burano Formation sulfate with supergene sulfate from oxidation of sulfide in the rocks. In sulfurous springs, both sulfur and oxygen isotope fractionations with respect to the source sulfate signatures may be ascribed to bacterial effects. However, the oxygen isotope exchange of sulfate with water should have been a very minor process as supported by the nearsurface temperature values estimated by sulfate-water oxygen isotope thermometry
Sulfur and oxygen isotope compositions of Upper Triassic sulfates from northern Apennines (Italy) : paleogeographic and hydrogeochemical implications
Upper Triassic bedded evaporite sulfate of the Burano Formation outcropping at Cerreto Pass between Tuscany and Emilia-Romagna in the Northern Apennines were analyzed for sulfur and oxygen isotope compositions, yielding d34S and d18O values of 15.5±0.4‰ and 10.8±1.2‰, respectively (mean ±99% confidence intervals). Combining these values with those of other Burano Formation sulfate deposits along the Apennine chain, mean for d34S and d18O values are obtained (15.2±0.2‰ and 10.9±0.5‰, respectively). These isotopic signatures are interpreted as preserved primary features, despite the fact that the Burano Formation underwent anchizone to epizone metamorphism during the Apennine orogenesis. An overall d18O value of 10.9±1.5‰ (mean ± pooled standard deviation), obtained by combining consistent sets of data from Italy and Spain, closely approaches that of gypsum deposited from the Tethys ocean during the Late Triassic. In addition, reviewing the isotope data published on Late Triassic evaporite sulfates from the Mediterranean area and abroad, several d34S values appear to be lower than the inferred primary isotopic signature, and seemly decrease from East to West in the Mediterranean region, suggesting a similar trend for the Tethys ocean sulfate. Possibly, 34S-depleted sulfate entered the ocean through oxidation of volcanic SO2 emitted in the atmosphere and degassed from the seafloor during the development of Late Triassic rifting. On the other hand, positive shifts of d34S and d18O values also occur, defining a common trend that may be related to synsedimentary biological effects or post-depositional metasomatic-metamorphic effects, the latter affecting particularly the d18O signature. Therefore, the d34S and d18O signatures of evaporite sulfate may provide a like "slide-rule" diagram to distinguish between isotopic effects related to biological or abiological processes, thus contributing to the reconstruction of paleoenvironments and paleogeographic settings. Based on the d34S-d18O "slide-rule", the isotopic composition of sulfate dissolved in spring and stream waters of northern Tuscany was interpreted in terms of origin of the sulfate and modifying processes in solution. It was concluded that sulfate in springs derives from Upper Triassic evaporite existing locally at depth (Burano Formation), whereas sulfate in streams is manifestly a mixture of Burano Formation sulfate with supergene sulfate from oxidation of sulfide in the rocks. In sulfurous springs, both sulfur and oxygen isotope fractionations with respect to the source sulfate signatures may be ascribed to bacterial effects. However, the oxygen isotope exchange of sulfate with water should have been a very minor process as supported by the nearsurface temperature values estimated by sulfate-water oxygen isotope thermometry
Isotope partitioning between cow milk and farm water: A tool for verification of milk provenance
Rationale: The oxygen and hydrogen isotope compositions of the water component of the milk from nine Italian dairy farms were studied together with the farm water for one year. The aim was to verify the importance of farm water and seasonal temperature variation on milk isotope values and propose mathematical relations as new tools to identify the milk origin. Methods: Milk was centrifuged to separate the solids and then distilled under vacuum to separate water. δ(18O/16O) and δ(2H/1H) analyses of the water molecules were carried out using a water equilibrator online with a mass spectrometer. For oxygen and hydrogen isotope determination, water was equilibrated with pure CO2 for 7.5 h and with pure H2 for 5 h, respectively. The isotope ratio value is indicated with δ (expressed on the VSMOW/SLAP scale) as defined by IUPAC. Results: The average annual isotope value of milk at the different cattle sheds is mostly related to the farm water suggesting that the drinking water is the most important factor influencing the isotopic values of the milk water. The milk/water fractionation factor correlates with the milking time and, thus, the seasonal temperature is best described by a 4th order polynomial regression line. A two-level check model was used to verify the milking provenance. Conclusions: This study shows that it is essential to analyze both milk and farm water to indicate provenance. A two-step verification tool, based on the difference between the measured and calculated δ(18O/16O)M values, and the difference between the calculated and estimated milk-water fractionation factors, allowed the source determination of milk. Both conditions must be met if the milk is considered to be from the Parmigiano-Reggiano production region. Although this approach was developed for this region, it can easily be tested and adapted to other dairy production areas
Study to optimize the effectiveness of Copper treatments for a low impact viticulture
Among all pathologies that afflict grapevine, Downy Mildew (DM) is the most important. Generally controlled
by using Copper (Cu), recently European Commission confirmed its usage but limiting the maximum amount to 28 Kg
per hectare in 7 years (Reg. EU 2018/1981). Anyway, in the grape growing context it is difficult to reduce the use of Cu
and generally chemicals, due to climate conditions, as well as climate changing. For this instance, Cu treatments have to
be improved. Hence, the aims of this work were to determine the possibility to reduce Cu using and evaluating the
variation of Cu cladding on grapevine leaves and grapes, in relation to the phytoiatric status. The efficacy level of the Cu
protection given to DM and the correlation among them was also assessed. Five organic vineyards located in
north-eastern of Italy were selected as experimental sites. Leaves and grapes were sampled during vegetative season
and analysed for determining the quantity of elemental Cu by the use of ICP AES. Spreading of DM in vineyards was
evaluated as well and the correlation between DM and Cu quantity on leaves and grapes was determined. First results
indicate that the mean level of Cu applied by farmers (range: 3.77 to 8.88 µg/cm
2 of Cu on leaves) during vegetative
season is not enough to have an optimal protection against DM (diffusion on grapes and leaves: 40 to 50%), although at
the maximum amount of Cu, the plant protection effect was quite good. Thus, Cu treatments have to be pondered on the
basis of meteorological data and previous infection of DM, so that it will be possible to determine the right quantity of Cu
to be applied in correlation to DM presence and weather. As future goals, data will be correlated with image analysis, in
order to quickly study the best conditions for Cu application directly on field and having back a real time information of
Cu cladding and risk classes of DM infection. In this way, it is possible to reduce inputs in plant defence and then
guarantee a quality and sustainable production of grapes, wines and must
Hydrogeological behaviour and geochemical features of waters in evaporite-bearing low-permeability successions: A case study in Southern Sicily, Italy
Knowledge about the hydrogeological behaviour of heterogeneous low-permeability media is an important tool when designing anthropogenic works (e.g., landfills) that could potentially have negative impacts on the environment and on people’s health. The knowledge about the biogeochemical processes in these media could prevent “false positives” when studying groundwater quality and possible contamination caused by anthropogenic activities. In this research, we firstly refined knowledge about the groundwater flow field at a representative site where the groundwater flows within an evaporite-bearing low-permeability succession. Hydraulic measurements and tritium analyses demonstrated the coexistence of relatively brief to very prolonged groundwater pathways. The groundwater is recharged by local precipitation, as demonstrated by stable isotopes investigations. However, relatively deep groundwater is clearly linked to very high tritium content rainwater precipitated during the 1950s and 1960s. The deuterium content of some groundwater samples showed unusual values, explained by the interactions between the groundwater and certain gases (H2S and CH4), the presences of which are linked to sulfate-reducing bacteria and methanogenic archaea detected within the saturated medium through biomolecular investigations in the shallow organic reach clayey deposits. In a wider, methodological context, the present study demonstrates that interdisciplinary approaches provide better knowledge about the behaviour of heterogeneous low-permeability media and the meaning of each data type
Plant Regeneration Above the Species Elevational Leading Edge: Trade-Off Between Seedling Recruitment and Plant Production
Mountains and their biota are highly threatened by climate change. An important strategy that alpine plants use to escape this change consists in seed dispersal and the ability of seeds to germinate and establish in new sites at higher elevation. Little is known about the environmental factors that can affect the regeneration of plants above the elevational limit of growth. We present the first field evidence of recruitment success and plant performance in consequence of upward shift from the alpine to the nival life zone. Seeds of four alpine grassland species were sown at the current elevational limit of growth (site A) and 200 m upward, in a nival environment (site N) located in the Italian Alps. At site N part of the seeds were subjected to experimental manipulation of temperature (using an Open Top Chamber, OTC) or soil (using soil from site A). Recruitment success, soil surface temperature and water potential were monitored for five consecutive years. At the end of the experiment, vegetative growth and foliar traits were measured on individuals from all treatments. Mean annual soil surface temperature and length of the growing season at site A were ca. 2°C higher and ca. 44 days longer than at site N. Seedling emergence and seedling establishment generally were higher at N (with or without OTC) on local soil than at site A or at site N with soil originating from site A. Conversely, production was higher at site A and at site N with soil originating from site A. Recruitment success above the elevational leading edge was enhanced by coarser and nutrient-poor soil, which promoted seedling emergence and establishment but constrained plant growth. This trade-off between seedling recruitment and plant production underlines adaptive consequence and environmental filtering, both critical to forecast community assembly and responses of alpine species to climate warming
Strontium and oxygen isotopes as indicators of Longobards mobility in Italy: an investigation at Povegliano Veronese
The arrival of the Longobards in Northern Italy in 568 CE marked a period of renewed political stability in the Peninsula after the collapse of the Western Roman Empire. The trajectory of the spread of Longobards in Italy across the Alps and into the South is known from many literary sources. However, their mobility and residence patterns at a population level remain to be fully understood. Here we present a multi-isotopic analysis (87Sr/86Sr and 18O/16O) of 39 humans and 14 animals buried at the Longobard necropolis of Povegliano Veronese (VR, Italy; 6th—8th century CE), to address mode and tempo of the spread of this population in the Peninsula. The geographical location of Povegliano Veronese plays a key role: the site lies along the Via Postumia, which was one of the main ancient Roman roads of Northern Italy, representing an important route in post-classical Italy. The integration of isotopic data with the archaeological evidence allowed us to determine the presence of individuals from at least three different regions of origin, building a diachronic map of the dynamics of mobility of this group in northern Italy
Study for the development of a rapid and non-destructive method for copper analysis in vineyards towards a precision fungal defense strategy
In the defense against downy mildew, copper is still widely used, particularly in organic management. At any rate, specific investigations are needed to significantly reduce the use of copper and minimize its environmental impact. This study, conducted in several farms in Friuli-Venezia Giulia (Northeast Italy), aimed to evaluate the concentration of copper on leaves in various climatic conditions, in order to create an important database for the development of a rapid control system through image analysis. The tests involved sampling leaves and grapes from bud break until the last treatment with copper-based products. After copper recovery using a nitric acid solution, the copper values were analyzed via ICP-AES analysis. Cuprotesmo imprints were also made on the same leaves to develop an application (APP) capable of quickly and non-destructively detecting copper on the leaf surface through image analysis. The analytical data revealed significant correlations between image analysis and copper values only in certain situations involving adult leaves. However, due to the variability in treatment situations, the use of the APP with image analysis for all copper defense scenarios is not yet feasible. Nevertheless, the results are encouraging and will serve for further extensive investigations to develop an image analysis system capable of detecting truly active copper and optimizing pesticide treatments for a precision defense strategy. This strategy aims to ensure low environmental impact, production sustainability, and grape quality
Early Proterozoic calc-alkaline and Middle Proterozoic tholeiitic dyke swarms from Central-Eastern Argentina: Petrology, geochemistry, Sr-Nd isotopes and tectonic implications
The Rio de La Plata craton in Argentina (Azul and Tandil regions) is characterized by Early Proterozoic (2·0 Ga) calc-alkaline and Middle Proterozoic (1·6 Ga) tholeiitic dyke swarms intruding the crystalline basement involved in the Transamazonian Orogeny (2·2-1·9 Ga). The calc-alkaline dykes have andesitic and rhyolitic compositions and trend east-west, whereas the tholeiitic dykes mainly trend N30°W and are represented by basalts with low (0·9-1·7 wt %) and high TiO2 (up to 3·7 wt %). The calc-alkaline dykes have primitive mantle (PM)-normalized trace element patterns enriched in Rb, Ba, K, La, Ce and Nd, and significant negative Nb and Ti anomalies. These dykes are characterized by εt(Nd) values of - 3 to - 4, similar to those of the EMI mantle component. Low-TiO2 tholeiitic dykes have low incompatible-element (IE) contents and PM-IE patterns with slightly positive or negative Nb spikes. They have variable εt(Nd) values (-0·5 to 12·1), which mainly reflect derivation from a depleted source mantle. High-TiO2 tholeiitic dykes have more enriched IE-PM patterns and are characterized by εt(Nd) values (-1·4 to -7·5) typical of an enriched source mantle. Chemical and isotopic data and melting modelling indicate that both calc-alkaline and tholeiitic dykes originated by different melting degrees of a heterogeneous source mantle, the variable IE enrichment of which may have occured in Late Archaean to Early Proterozoic times. The emplacement of the calc-alkaline dykes is associated with the transtensional stage of the Transamazonian Orogeny, whereas the tholeiitic dykes reflect extensional tectonics succeeding the Transamazonian event. The calc-alkaline and tholeiitic dykes are similar in emplacement age and characteristics to metamorphosed granites and volcanic rocks outcropping within the Namaqua fold belts of southwestern Africa (Richtersveld and Witberg-Aggeneys-Gamsberg provinces); this may indicate that the Rio de La Plata craton and southwestern Africa were contiguous in Early-Middle Proterozoic times.Facultad de Ciencias Naturales y MuseoLaboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológic
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