Encarregado de proteção de dados pessoais - DPO: regulamentação e responsabilidade civil

Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.Localização na estante: 342.721:004.738.5(81) Q3

STEROLS AND BILE ACIDS IN URBAN AND RURAL SOILS AS FAECAL MARKERS OF LAND-USE SINCE THE BRONZE AGE

International audienceFor ancient societies, the control of agriculture and animal domestication were extremely important to their development. After having domesticated different animals as livestock, ancient societies developed techniques such as manuring to improve culture yields. There are numerous evidences in archaeological records of animal breeding (bones, coprolithes, spherolites). Reversely, despite few studies dedicated to buildings and caves, the only evidence for manuring and breeding out of archaeological context, were acquired on recent soils (Bull et al., 1998; Birk et al., 2011). The aim of this study is to test the potential of faecal biomarkers preserved in soils to spatially resolve (at the field-scale) the strategies of land use (buildings, breeding and manuring) in ancient times. For this, faecal biomarkers (sterols and bile acids) of animals (Humans, cow, horse, pig and sheep), sediments from a septic tank (beginning of 19th century) and soils of distinct land use (pasture and forest) were characterized. Then, archaeogical samples were analysed: (i) agricultural soils, middens and settlement layers dated back to the Bronze Age in Lake Bourget shore, (ii) settlement layers recovered during excavations in a medieval building (15th century, Orléans). Sterols and bile acids were isolated from archaeogical samples following Zocatelli et al. (2012). Neutral fraction was further separated by flash chromatography. The alcohol fraction was silylated and analysed by GC-MS with a Polaris TRACE-GCQ. From the twenty sterols and bile acids identified, the following faecal biomarkers were found: coprostanol (Cp), methyl-coprostanol (mCp), ethyl-coprostanol (eCp), lithocholic acid (LC), deoxycholic acid (DOC), cholic acid (C), chenodeoxycholic acid (CDOC), hyodeoxycholic acid (HDOC), ursodeoxycholic acid (UDOC) and 3α-hydroxy-12-oxo-5β-cholanoic acid (oxoDOC). To identify possible sources of faecal compounds, bile acid imprints and sterol ratios were employed: 1) (Cp+epi-Cp)/(eCp+epi-eCp); 2) (Cp+epi-Cp)/(Cp+epi-Cp+5α-cholestanol); 3) (Cp+epi-Cp)/cholesterol. Sterol content of animal faeces clearly distinguished two groups: omnivores (Humans and pig) and herbivores (cow, horse and sheep). Then, Human and pig imprints were distinguished from bile acids. Faecal biomarkers were detected in all archaeogical samples (i and ii) and allowed the distinction between omnivores, herbivores and mixed faecal biomarker imprints in the sample set. Samples from middens of Lake Bourget catchment contained a mixture of Human and breeding faecal sterols. Bile acids corroborated these results. Furthermore, faecal biomarkers detected Le Bourget catchment soils formerly cultivated for millet, evidenced past manuring practices (mCp, eCp and DOC). High contents of coprostanols (Cp and eCp) and bile acids (LC, DOC and C) in settlement layers from Lake Le Bourget shore evidenced the co-occurrence of animals in the same area. Analysis of faecal materials from a medieval building in Orléans revealed only Human occupation (Cp, LC, DOC, CDOC, C and oxoDOC). Finally, this study showed that faecal biomarkers are efficient to provide information on the use of space in areas inhabited by humans. From a more general point of view, these results illustrateed that faecal biomarkers could reveal how Human societies shaped their environment through times

CHEMICAL DIVERSITY OF SOIL LIPIDS REFLECTS SURROUNDING BIODIVERSITY IN A FRENCH PEATBOG

International audienceThe aims of this study are to characterize the spatial variability of biomarker imprints in a peatland and to test to which extent this variability can be related to the surrounding vegetation. Since the mid 1970’s La Guette peatland (région Centre, France) has been colonized by vascular plants. Nowadays it is totally colonized by Molina caerulea and, to varying extent, by Pinus sylvestris and Betula pendula. In nine stations representative of distinct vegetation cover, we analysed the lipid composition of soil developed under Molinia caerulea. The lipids of the six most abundant plants encountered in the peatland were analysed as reference samples: Sphagnum rubellum, Erica tetralix, Calluna vulgaris, Molinia caerulea, Betula pendula and Pinus sylvestris. For all these samples, lipids were ultrasonically extracted with DCM and then separated into neutral, acidic and polar compounds. The neutral fraction was further separated by flash chromatography to afford (i) aliphatics and aromatics; (ii) ethers, esters, ketones and acetates and (iii) alcohols. 5α-cholestane was added prior to analysis for quantitation. Lipid fractions were then identified and quantified by gas chromatography-mass spectrometry. In order to quantify their density, trees were counted within circles of increasing radius (giving areas of 3.14; 12.6; 28.3; 50.3 and 78.5 m2) around the sampling plot. After counting, total tree density was determined as well as individual P. sylvestris and B. pendula density. For each sample (n=9) regressions were calculated between (i) lipids and (ii) the density of the tree (n=9). This calculation was reproduced for each counting surface. Then, the resulting regression coefficient was plotted against each surface of counting. Apart from ubiquist compounds such as n-alkanes and triterpenoid ketones, we found in soils several biomarkers for which the source could be constrained. Taraxeryl, friedelanyl and moretenyl acetates were detected. Friedelanyl and moretenyl acetates were found in high amounts in open vegetation plots (9.7 and 2.9 µg.g soil-1, respectively). They were also detected in E. tetralix and C. vulgaris (Ericaceae) and, probably due to contamination, in S. rubellum. Multiflorenyl and two unknown acetates, also present in low contents, may originate from undetermined, less abundant plant. Four methoxy-serratenes (Le Milbeau et al., 2013) and seven tricyclic diterpenes were detected in both soils and P. sylvestris needles. Strong correlation (r = 0.997; p ≤ 0.0001) of their respective abundances in soils attest to their common origin and similar conservation potential. The presence of betulin and related compounds in soil samples and in B. pendula leaves are in agreement with the admitted use of these biomarkers to track the former presence Betula species in soils and sediments (i.e. Otto and Simoneit, 2001). The source of these biomarkers being defined, we then assessed their spatial distribution at the nine sampling sites. Although not abundant, triterpenyl acetates, methoxy-serratenes, diterpenes and betulin derivatives exhibit a higher coefficient of variation along sampling sites than other compound such as n-alkanes or triterpenoid ketones.The correlation between methoxy-serratenes and the number of P. sylvestris in the nine sampling sites increases with the surface used for the calculation (r = 0.93, p<0.022). These values indicate that specific biomarkers of P. sylvestris in soil samples and surrounding vegetation are spatially linked. The same applies for B. pendula and betulin derivatives (r = 0.96, p<0.008). The degradability of the betulin and its relatively high solubility may induce lost and leaching out of the sampling point. Our results provide evidence that selected biomarkers in soil samples can give a reliable picture of the surrounding vegetation. It also quantifies the area of influence of trees on the soil lipid composition, over 20 m². The approach combining tree counting and quantitation of specific biomarkers that was developed in the frame of this study proved to be efficient in evidencing the spatial control of the surrounding vegetation on lipids distribution in a peatland invaded by vascular plants.REFERENCESLe Milbeau, C., Lavrieux, M., Jacob, J., Bréheret, J.G., Zocatelli, R., Disnar, J.R., 2013. Diversity of methoxy-serratenes in a soil under a conifer forest and their potential as biomarkers of Pinaceae. Organic Geochemistry 55, 45-54.Otto, A., Simoneit, B.R.T., 2001. Chemosystematics and diagenesis of terpenoids in fossil conifer species and sediment from the Eocene Zeitz formation, Saxony, Germany. Geochimica et Cosmochimica Acta 65:20, 3505–3527

Spatial variability of soil lipids reflects vegetation cover in a French peatland

International audienceThe purpose of this study was to show how current vegetation in a peatland is imprinted in the lipid fraction of the underlying soil. La Guette is a fen peatland in Central France dominated by Sphagnum spp. and ericaceous shrubs, colonized by sedges (Molinia caerulea) and trees since the 1970s (Betula pendula and Pinus sylvestris). Lipid were identified and quantified in the most abundant plants and in samples collected at the base of M. caerulea tussocks. Among relevant biomarkers, tricyclic diterpenes and methoxy-serratenes stood out as specific for P. sylvestris, betulin derivatives as specific for B. pendula, and some pentacyclic triterpene ketones and acetates as biomarkers of Ericaceae. Multivariate analysis applied to biomarker concentration in soil samples from several sites permitted distinguishing three different vegetation types: vegetation cover: (i) closed vegetation dominated by P. sylvestris; (ii) closed vegetation dominated B. pendula and (iii) open vegetation or semi-open vegetation (early colonization by trees) constituted mainly by Ericaceae, Sphagnum and graminoids. Comparison of tree-specific biomarker concentrations with estimates of tree biomass allowed establishing of quantitative relationships that were valid over at least 80 m2 around the sampling site. Although preliminary, the results are promising in attempting to relate biomarker concentrations in geological archives to paleo-biomass

Preservation of an ancient grassland biomarker signature in a forest soil from the French Massif Central

International audienceIn response to the lack of studies focussing on the residence time of molecular biomarkers in soils, the lipid content of three soil profiles from the French Massif Central with different land use history were examined. The free neutral lipid content of two reference soil profiles developed under grassland and forest vegetation, and of a former grassland soil converted to forest about 60 years ago, was analysed using gas chromatography - mass spectrometry (GC-MS). Wax esters as well as the ratio of major homologues of n-alkanes and n-alkan-2-ones could be used to characterize the overlying vegetation in the reference forest and grassland soil profiles, but failed to distinguish the respective grassland and forest contributions to the profile of the soil that had changed use. For n-alkanes and n-alkan-2-ones, the failure might be attributed either to mixing of the molecular patterns inherited for the former and current plant cover, whereas for compounds such as wax esters simple degradation is likely to be involved. Conversely, iso- and anteiso- C15:0 fatty acid methyl esters (FAMEs; of bacterial origin), steroids (tracing cattle faecal contamination), tricyclic diterpenoids and their oxygenated derivatives, as well as methoxyserratenes (inherited from Pinaceae) and triterpenyl acetates (specific to the Asteraceae), proved to be effective in distinguishing current land use for the reference soil profilesand for the converted soil. The persistence of these compounds in the changed use soil allowed us to estimate their residence time in soil

First detection of triterpenyl acetates in soils: sources and potential as new palaeoenvironmental biomarkers

International audienceUnderstanding past reactions of ecosystems under natural and anthropic constraints is of crucial importance to anticipate the consequences of the current global changes. Unraveling natural and anthropic impacts on environments requires the reconstruction of ancient land-uses. As a part of a larger project aiming at developing new molecular biomarkers in soils that could be specific of their overlying vegetation, we have analyzed the neutral lipid content of soils developed under distinct types of plants. Soils were sampled around Lake Aydat, in Central France, of which the catchment is covered with pastures/meadows, forests and moors. The ketone/ester lipid fraction from soils under pastures or meadows contains a series of 14 pentacyclic triterpenyl acetates with a large structural diversity (Fig. 1). This discovery motivated an extensive phytochemical literature survey (240 references) that showed restricted potential sources of triterpenyl acetates. -amyrin, taraxeryl, glutinyl, -amyrin, and multiflorenyl, acetates are found in very distinct taxa and are thus poorly informative. Conversely, lupeyl, bauerenyl, isobauerenyl, taraxasteryl and -taraxasteryl acetates appear more specific since they are majoritary reported in Asteraceae. Pichierenyl, isopichierenyl and gammacerenyl acetates seem to be the more specific ones since they are produced by a single known species, Picris hieracioides L. (hawkweed oxtongue, Asteraceae)

Pastoral activities and soil erosion processes: calibration and confrontation of organic and minerogenic markers from Pyrenean archives (Orry de Théo and Troumouse peat bogs)

International audienceFor more accurate prediction of the consequences of current global warming, it is important to disentangle the past impact on ecosystems of climate variability and human activities, in both the long and short term (Dearing and Jones, 2003). The mechanical erosion of continental surfaces mainly results from climate forcing (precipitation/runoff, vegetation changes…), but may be initiated, amplified and accelerated by anthropization (deforestation, plowing, grazing…). High altitude ecosystems are sensitive and therefore constitute relevant targets in which soil-erosion quantification can be used both to reconstruct climate changes (Simonneau et al., 2014) and to document the local consequences of human activities. In addition, such human-induced soil erosion indirectly reflects socio-ecological trajectories over time. For thousands of years, grazing has affected Pyrenean areas and is considered to be the main biotic factor creating pressure on ecosystem structure and the dynamics of mountain pastures (Galop et al., 2004; Mazier et al., 2009). Indeed, recent studies suggest that pastoral activities increase soil erosion rates (Adler and Morales, 1999; Ayala and French, 2005), especially in mountainous regions (Hall et al., 1999). Yet, though such interaction between grazing and erosion can be hypothesized, the causal relationship has been neither established nor quantified (Thormes, 2007). Such proof, however, is essential if public policy in the field of land-use management is to be credible. With this in mind, the ongoing French research program " pastoralisM versus erosiOn: expLoration of molECULar biomarkers for tracking human/Environment interactions " (MOLECULE, Labex DRIIHM – CNRS INEE) clearly aims to reconstruct the impact of grazing on soil erosion during the Late Holocene. In well-dated peat bog archives (Orry de Théo and Troumouse, Pyrenees), soil erosion (from organic and minerogenic markers) is studied alongside pastoralism (from coprophilous fungi and fecal molecular biomarkers: bile acids and sterols). The peat bog archive from Orry de Théo (Eastern Pyrenees, fig. 1) over the last two centuries is used to calibrate fecal tracers. Quantitative evolution of pastoralism tracers is compared to size and composition of livestock populations as described in detail in local archives (Galop et al., 2011). The markers of pastoralism can thus be quantitatively related to proportions of the livestock (i.e. ovine versus bovine). The authors then explore any quantitative relationship between the number of tracers and the size of the livestock. Finally, it is hoped that crucial information will emerge concerning any latency or time lag in the recording of molecular tracers due to varying residence times in soils or to varying transportation times from source to the archive. The Troumouse peat bog (Central Pyrenees, fig. 1) covers the last 6000 years and is located only a few kilometers from Lake Barroude (fig. 1), where climate-induced erosion processes over the Holocene have been quantified. At Troumouse, soil erosion fluxes reveal six major detrital phases dated from 3910-3855, 3445-3225, 2780-2740, 2655-2525, 1700-1510 and 735-515 cal BP. Anthropogenic indicators suggest that human activities in the vicinity of the bog date from 5000 cal BP. Moreover, Louis Ramond de Carbonnières described intensive historical land-use management for grazing activities in the area but specified neither the type nor the number of animals involved in these practices. By applying our calibration to this new sequence and comparing local soil erosion fluxes, potentially influenced by grazing, to the local climate signal, the authors hope to demonstrate and quantify pastoralism and to establish whether or not it is a true agent of erosion

Methoxy-serratenes as discriminant biomarkers for soils developed under conifer forests

PosterInternational audienceThe evolution of landscapes through time constitutes a challenge for both archaeologists and paleoenvironmentalists. For example, human deforestation (for cultivation and building) strongly affected the shape of continental surfaces with supposed impacts on the global carbon cycle of which the timing and extent remains controversial

LGPD x campanha eleitoral: perspectivas e desafios

Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.Localização na estante: 342.8’721(81) L687cOrganizado por: Julia Lonardoni Ramos, Daniel Zonzini Lattanzio, Guilherme de Salles Gonçalves e Renata Capriolli Zocatelli Queiro