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Saffron is regarded as the most expensive spice, due to its laborious production and the required environmental conditions. Iran accounts for ca. 90% of the global saffron production. Very often, saffron of a production other than Iran is significantly more expensive than Iranian saffron. As fraught and mislabeling with respect to saffron is common, besides tools for the control oft he authenticity of saffron (detection of fake-saffron), also techniques are required to control the declared origin of saffron, to prevent consumer deception.In the present study I compare C-, H-, O-, N- isotope patterns of saffron samples of various geographic origin. Furthermore, 87Sr/86Sr of saffron samples are investigated and compared.The results show notable variations of the isotope patterns of saffron samples of different geographic origin, but also of different vintages for samples of same geographic origin. 87Sr/86Sr results indicate a good differentiation for certain countries of origin (e.g. Morocco and India), but other geographic origins cannot satisfyingly differentiated. The discrimination of Iranian saffron from saffron of other geographic origin remains a challenging task.

We read with interest the publication by Sinkovic et al. [...]

I was very interested in the investigation of the

Anecdotal evidence suggests that spontaneous alcoholic fermentation of grape juice is becoming a more popular option in global wine production. Wines produced from the same grape juice by inoculation or spontaneous fermentation usually present distinct chemical and sensorial profiles. Inoculation has been associated with more similar end-products, a loss of typicity, and lower aroma complexity, and it has been suggested that this may be linked to suppression of the local or regional wine microbial ecosystems responsible for spontaneous fermentations. However, whether inoculated fermentations of different juices from different regions really end up with a narrower, less diverse chemical profile than those of spontaneously fermented juices has never been properly investigated. To address this question, we used grape juice from three different varieties, Grüner Veltliner (white), Zweigelt (red), and Pinot noir (red), originating from different regions in Austria to compare spontaneous and single active dry yeast strains inoculated fermentations of the same grape samples. The chemical analysis covered primary metabolites such as glycerol, ethanol and organic acids, and volatile secondary metabolites, including more than 40 major and minor esters, as well as higher alcohols and volatile fatty acids, allowing an in depth statistical evaluation of differences between fermentation strategies. The fungal (mainly yeast) communities throughout fermentations were monitored using automated ribosomal intergenic spacer analysis. The data provide evidence that inoculation with single active dry yeast strains limits the diversity of the chemical fingerprints. The fungal community profiles clearly show that inoculation had an effect on fermentation dynamics and resulted in chemically less diverse wines.

Host–microbiome interactions are specific and not random, making them defining entities for the host. The hypothesis proposed by various researchers earlier, that both plants and animals harbor specific inheritable core microbiome, is being augmented in the present study. Additionally, a case for using microbial fingerprint as a biomarker, not only for plant identification but also as a geographical indicator, has been investigated, taking Crocus sativus, saffron, as a study material. Crocus sativus, a monogenetic herb, on account of its male sterility and vegetative propagation, is reported to lack genome based molecular markers. Cormosphere microbiome (microbiome associated with corm) has been compared across three geographical locations, in two continents, to identify the core and unique microbiome, during the vegetative phase of its growth. Microbiome analysis done at phylum and genus level, using next generation sequencing technology, revealed that cormosphere at three locations harbored common phyla. At genus level, 24 genera were found common to all three geographical locations, indicating them to be part of the core microbiome of saffron. However, there were some bacterial genera unique to Kashmir, Kishtwar, and Morocco that can be used to develop microbial markers/geographical indicators for saffron grown in these regions. This is a preliminary study, indicating that the location specific bacterial community can be used to develop microbial barcodes but needs further augmentation with high coverage data from other saffron growing geographical regions.

It is proposed that unstable temperature conditions in the Late Wuchiapingian and Early Changhsingian (Late Permian) changed in the Boreal Superrealm to less contrasting climatic conditions in the Late Changhsingian and Early Induan (the formation time of trap formation of the Siberian Platform), with a stable trend of increasing temperature in the Early Triassic. The problem of the absence of signs of mass extinction of marine organisms at the Permian–Triassic boundary in the Boreal Superrealm is discussed.

The end-Permian mass extinction was the most severe biotic crisis in Earth’s history. In its direct aftermath, microbial communities were abundant on shallow-marine shelves around the Tethys. They colonized the space left vacant after the dramatic decline of skeletal metazoans. The presence of sponges and sponge microbial bioherms has largely gone unnoticed due to the sponges’ size and the cryptic method of preservation. In addition to sponge dominated facies recently described in South Armenia and Northwestern Iran, we describe here sponge-microbial bioherms cropping out in two well-known Permian-Triassic boundary localities: the Kuh-e Hambast section, south-east of Abadeh city and the more distal Shahreza section, near Isfahan. In both sections, the extinction horizon is located at the top of an upper Changhsingian ammonoid-rich nodular limestone, calledParatiroliteslimestone. At Kuh-e Hambast, the overlying decimetric thick shale deposit called “boundary clay,” the latest Permian in age, is conformably overlain by well-dated transgressive basal Triassic platy limestone containing four successive levels of decimeter to meter scale, elongated to form cup-shaped mounds made of branching columnar stromatolites. Sponge fibers from possibly keratose demosponge, are widely present in the lime mudstone matrix. At the Shahreza section, above the extinction level, the boundary clay is much thicker (3 m), with thin platy limestone intervals, and contains two main levels of decimeter to meter scale mounds of digitate microbialite crossing the Permian-Triassic boundary with similar sponge fibers. Three levels rich in thrombolite domes can be seen in the overlying 20 m platy limestone of earliest Triassic age. Sponge fibers and rare spicules are present in their micritic matrix. These sponge fibers and spicules which are abundant in the latest Permian post-extinction boundary clay, followed microbial buildups during the Griesbachian time.

In this study, we compare the stable isotope composition of oxygen and carbon of wines from four Central and Southeastern European countries and from Argentina to study the similarities and differences in the isotope signatures and, thus, the potential of differentiation of the various wine-growing countries. We observe similar trends for wines from Austria, Slovenia, and Romania with respect to the vintages 2008 and 2009, which are absent in the Montenegrin and Argentinean samples. It is speculated that the weather develops similarly for Austria, Slovenia, and Romania, as these countries are positioned at a similar latitude and not too far away from each other (general central and eastern European weather situation), whereas Montenegro is not influenced by the latter being situated farther south and dominantly influenced by the Adriatic Sea. Investigations on further vintages are needed to test this assumption.

Joachimski et al. carried out geochemical investigations to study seawater temperature changes and their potential triggers across the Permian-Triassic Boundary (PTB). Unfortunately, in our opinion, an incorrect biochronology was applied to define the PTB, and the existing alternative was not considered, nor the reasoning explained. As a consequence, Joachimski et al. report diachronous temperature changes for the investigated Chanakhchi section with respect to the global stratotype section and point (GSSP) in Meishan, China. This discrepancy disappears when the, in our view, correct position of the PTB is adopted by using the proper biochronology.

Rio Tercero Reservoir (RTR) is the largest artificial reservoir in the province of Cordoba (Argentina). Water, sediment, plankton, shrimp (Palaemonetes argentinus), and fish (Odontesthes bonariensis) were collected during the wet season (WS) and dry season (DS) from this reservoir. Concentrations of Ag, Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, P, Pb, Se, U, and Zn were determined to investigate their respective bioaccumulation pattern and trophic transfer in the food chain. Results showed that their concentrations in water were rather low except Pb, which exceed the limits considered as hazardous for aquatic life. The enrichment factor (EF) in sediments showed that most of the element were derived from anthropogenic sources. Furthermore, the bioaccumulation factor (BAF) determined that the elements undergo bioaccumulation, especially in organisms such as plankton. The invertebrates were characterized by the highest BAF for Cu, P, and Zn in both seasons; Ag, As, and Hg during WS; and Se during DS. Fish muscle registered the highest BAF for Hg (DS) and Se (WS). A significant decrease in Al, As, Cd, Cr, Cu (DS) Fe, Mn, Ni, Pb, Se, U, and Zn (DS) concentrations through the trophic chain was observed, indicating biodilution. Some notable exceptions were found as Cu (WS), Hg (DS), and P (both season) that showed biomagnification. Further studies are needed to establish differential behavior with different species and pollutant, particularly when the potential transfer is to edible organisms.

Mareza Spring is used for the water supply of Podgorica (capital of Montenegro) since over 70 years. It is located in the central part of Montenegro in the north-western part of Podgorica Valley. The recharge area and origin of groundwater of this karstic source are not known well. This is primarily due to the fact that drainage divides in karst terrains are the unknown and insufficiently examined segments. There are a few hypotheses about the origin of water: 1. from the Zeta River which flows few kilometres north-east from Mareza Spring, 2. from the Morača River which partly sinks at the exit of the canyon (around 10 km east from Mareza Spring), and 3. from the Prekornica Mountain recharge area that is located 10-20 km north-east from the spring (that is a karst plateau with average altitude around 1,000 m asl). Therefore, the isotopic techniques (altitude effect, comparison) could be useful for testing these assumptions. In the present study monitoring of stable isotopes (2H, 18O) in precipitation, surface water and groundwater of this area is carried out to determine the origin of water and adequate protection of Mareza Spring.

Food products of certain geographic origin are more valued by consumers than the same commodities from other regions. Therefore, there is the risk and fear that incorrect labelling and declaration of geographic origin can occur to increase profit. Thus, a control of declared geographic origin is required to ensure correct labelling and to identify fraud.For this purpose, apricot samples of the recent vintage (2019) are investigated to differentiate samples from different apricot-producing regions in Austria, Slovakia and other countries. The isotope composition of the elements hydrogen (H), carbon (C), nitrogen (N) and oxygen (O) of fruit pulp (H, C, N, O), fruit stone (H, C, O) and fruit juice (O) is analysed to find appropriate parameters for the differentiation of geographic origin. The investigation of different sample tissues (pulp, stone, juice) supports a better differentiation of geographic origin due to different seasonal intervals influencing the respective commodities.Within the frame of the project 3 vintages will be investigated and analysed for stable isotopes as well as other analytical techniques (molecular markers). The combination of all sample data (including previously accumulated data, e.g. Horacek 2017, Horacek 2019) will lead to an improved differentiation and identification of geographic origin.This work is a contribution to the Interreg project IDARPO partially funded by the EU-Interreg program.References:Horacek, M., 2017, Isotope investigation of apricots from the Wachau-area/Lower Austria („Wachauer Marille“) to control the declared geographic origin: A pilot study – first results. Mitteilungen Klosterneuburg. 67, p. 219-228.Horacek, M., 2019, Stable isotope analysis for control of declared geographic origin of Austrian apricots. EGU 2019, Vienna.

We propose an updated ammonoid zonation for the Permian–Triassic boundary succession (the lower Nekuchan Formation) in the Verkhoyansk region of Siberia: (1) Otoceras concavum zone (uppermost Changhsingian); (2) Otoceras boreale zone (lowermost Induan); (3) Tompophiceras morpheous zone (lower Induan); and (4) Wordieoceras decipiens zone (lower Induan). The Tompophiceras pascoei zone, previously defined between the Otoceras boreale and Tompophiceras morpheous zones, is removed in our scheme. Instead of this the Tompophiceras pascoei epibole zone is proposed for the lower part of the Tompophiceras morpheous zone. New and previously published nitrogen isotope records are interpreted as responses to climatic fluctuations in the middle to higher palaeolatitudes of Northeastern Asia and these suggest a relatively cool climatic regime for the Boreal Superrealm; however the trend towards warming across the Permian–Triassic boundary transition is also seen. The evolutionary development and geographical differentiation of otoceratid ammonoids and associated groups are considered. It is likely that the Boreal Superrealm was their main refugium, where otocerid, dzhulfitid and some other ammonoids survived the major biotic crisis at the end of the Permian. The similarity of ontogenetic development of suture lines of Otoceras woodwardi Griesbach and O. boreale Spath gives some grounds for suggesting a monophyletic origin of the genus Otoceras, having bipolar distribution.

N and C isotopic data are recorded and presented for the first time for the Lower Triassic claystones of Southern Primorye (Abrek Section). Five N isotope intervals and 11 more or less pronounced negative C isotope excursions, likely to reflect instability of the temperature regime and the oceanographic situation in the Early Triassic, are recognized in the section. The most favorable conditions for ammonoid recovery and other marine organisms in the Early Triassic (after the end- Permian ecological crisis) were associated with the late Induan—early Olenekian transgression and probable cooling.

The Kamenushka Formation, exposed in the northern part of South Primorye (Kamenushka-1 and Kamenushka-2 sections), is one of the few localities in the world with richly fossiliferous Lower–Upper Olenekian sedimentary successions. Lower to Middle Triassic ammonoid-, brachiopod- and conodont-bearing silty-clayey deposits of the Kamenushka-1 and Kamenushka-2 sections have been isotope-geochemically investigated in detail. As a result, these sections, together with the previously investigated Abrek Section, exposed in the southern part of South Primorye, provide almost complete 15Norg- and 13Corg- records for the Lower Triassic of this region. Nine N-isotope intervals and the five negative C-isotope excursions, reflecting, apparently, unstable climatic and hydrological conditions, have been distinguished in the Lower Triassic of South Primorye. On the basis of the new C-isotope data the Mesohedenstroemia bosphorensis Zone (upper part), Shimanskyites shimanskyi and Neocolumbites insignis zones of South Primorye are correlated now with the Lower Smithian part of the Yinkeng Formation, the Upper Smithian part of the Helongshan Formation and the Middle Spathian part of the Nanlinghu Formation in South China, respectively, as has been observed in the Abrek, Kamenushka-2, West Pingdingshan and Majiashan sections.

The concentration of metals (Al, Cr, Mn, Fe, Ni, Cu, Zn, Ag, Cd, Hg, Pb, U), As and Se in different ecosystem components (water, sediment, plankton, shrimp, and fish muscle) has been determined in a eutrophic reservoir in the Province of Córdoba (Argentina). Los Molinos Lake (LML) was sampled during the dry (DS) and wet seasons (WS) in order to examine the bioaccumulation and transfer of these inorganic elements through the food web. Stable nitrogen isotope (δ15N) was used to investigate trophic interactions. According to this, samples were divided into three categories: plankton, shrimp (Palaemonetes argentinus) and fish (Silverside, Odontesthes bonariensis). The bioaccumulation factor (BAF) was calculated for the organisms, and it was determined that the elements analyzed undergo bioaccumulation, especially in organisms such as plankton. The invertebrates were characterized by the highest BAF for Cu and Zn in both seasons, As (DS), and Cd and Hg (WS). The fish muscle was characterized by the highest BAF for Se (WS), Ag and Hg (DS). On the other hand, a significant decrease in Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and U concentrations through the analyzed trophic web during both seasons was observed. Moreover, a significant increase in Hg levels was observed with increasing trophic levels in the DS, indicating its biomagnification. Despite the increasing impact of metals, As and Se pollution in the studied area due to urban growth and agricultural and livestock activities, no previous study has focused on the behavior and relationships of these pollutants with the biotic and abiotic components of this aquatic reservoir. We expect that these findings may be used for providing directions or guidance for future monitoring and environmental protection policies. Fil: Griboff, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina Fil: Horacek M. Blt Wieselburg Lehr- und Forschungszentrum Francisco Jo; Austria. Universidad de Viena; Austria Fil: Wunderlin, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina Fil: Monferran, Magdalena Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina

Data on the N and C isotopic composition are presented for the Lower Triassic claystones of the Abrek section of southern Primorye (Far East). The results showed five N isotopic intervals and several negative C isotopic excursions of the Induan–lower Olenekian stages of the Abrek section.

We have obtained the first detailed δ13Сorg record in Permian-Triassic boundary sediments in deepwater facies in Northeast Asia (Kolyma–Omolon region, Balygychan Basin). Our data show good convergence both with the Setorym River section (South Verkoyansk region), where the Permian-Triassic boundary has been determined approximately, and with a number of other sections of Permian-Triassic boundary sediments in the Boreal and Tethyan Superrealms, in particular, in the Buchanan Lake section in Arctic Canada, the Festningen section on Spitsbergen, the Wadi Shahha section on the Arabian Peninsula, and published sections in the Dolomites.

Vitis vinifera is one of the most widely planted crops and holds important economic value in South Africa and Austria. Grapes obtained from this plant harbour a complex fungal community which plays a crucial role in the wine fermentation process and influences wine flavour and aroma. For many years the contributions of the natural yeasts has been eclipsed by the use of active dry yeast (ADY) inoculant, mainly of the species Saccharomyces cerevisiae. However, recent studies show a growing interest in deciphering the natural microbial diversity and in promoting its persistence during fermentation in order to enhance wine typicity. The current preliminary study aims to provide a first broad assessment of the fungal community fingerprint of different grape varietals from different wine producing areas in Austria and South Africa through Automated Ribosomal Intergenic Spacer Analysis (ARISA). The ARISA profiles separated the samples according to country of origin, and suggested some regional and varietal separation within each country. Future work will evaluate the contribution of these fungal communities to wine chemical composition and sensorial distinctness.

Investigation on discrimination of geographic origin in border areas is carried out by investigating and comparing authentic wine samples from the border areas of Austria, Czech Republic, Slovakia (and from Serbia) by applying different physico-chemical methods (e.g. IRMS, NMR, ICP-MS, ICP-OES, EPR, HPLC, UV-VIS, etc…). The comparison of the data sets from the participating countries and the different applied methods demonstrates, to which extent a differentiation can still be achieved in the border areas of the respective countries, which methods prove most efficient and sensitive and if a combination of methods leads to an increased sensitivity. Furthermore, we also investigate the potential causes for the differentiation, as the environment, different agricultural practices or enology. Analysis of two consecutive vintages shows significant variations between the two years, complicating direct comparison of regions beyond individual vintages. Still, several parameters are identified enabling correct and complete differentiation. However, some of them have been found to represent lab effects, whereas others are interpreted as resulting from different agricultural practices or environmentally driven. Only the latter two ones, if consistent, can be used for discrimination of geographic origin.

In the presented project the investigation on discrimination of geographic origin of wine in from border areas is carried out. Authentic wine samples from the border areas of Austria, Czech Republic, Slovakia (and from Serbia) are investigated and compared by applying different physico-chemical methods (e.g. IRMS, NMR, ICP-MS, ICP-OES, EPR, HPLC, UV-VIS, etc.). The comparison of the data sets from the participating countries and the different applied methods will show, to which extent a differentiation can still be achieved in the border areas of the respective countries, which methods prove most efficient and sensitive and if a combination of methods will lead to an increased sensitivity. Furthermore, we also investigate the causes for the potential differentiation, which might be environmentally determined, due to different agricultural and/or enological practices. Results from the first investigated vintage 2016 show a good separation of the respective geographic origins by isotope ratios and element concentrations as well as by other parameters. The relevant parameters for differentiation now have to be critically evaluated to exclude potential lab influences.

The invasive Spanish slug (Arion vulgaris) is an important pest species in agriculture and horticulture in Europe. In the last decades it has spread across the continent where it outcompetes native slug and snail species, thus posing a threat for biodiversity. A popular anecdote suggests to promote Roman snails (Helix pomatia) in gardens because they are able to controlA. vulgaris. We examined a potential interrelationship between these two species using a mesocosm experiment with lettuce plants.13C-15N stable isotope labelling of lettuce allowed us to investigate interactions betweenHelixandArionon weight gain/loss and herbivory. Additionally, we wanted to know whether different watering regimes (daily vs. every 3rd day watering of weekly amount) and earthworms alter these interactions. Egg predation ofHelixonArioneggs was further tested in a food-choice experiment.Arionshowed a five times higher herbivory per body mass thanHelixin a single-species setting. However, in mesocosms containing both species percentage of herbivory per body mass was significantly lower than inArion-only mesocosms, especially when watered every three days. Overall isotope uptake via eaten lettuce was unaffected by the presence of the other species. Only very little predation (three out of 200 eggs) ofHelixonArioneggs was observed. Our results provide no evidence for a clear dismissal or confirmation of the popular gardener’s anecdote thatHelixsnails have a negative effect onArionabundance or herbivory.

We present new data on the structure and age of the upper Permian strata in the basin of the Setorym River (tributary of the Vostochnaya Khandyga River) in the South Verkhoyansk region, represented by the Imtachan Formation and the lower part of the Nekuchan Formation. Based on the new findings of bivalve fossils from the Intomodesma costatum Zone, as well as on the study of carbon isotopes in the shells and carbon isotopes of the organic matter of the host mudstones, we have for the first time proved the completeness of the Permian section. The detailed description of the contact between the Imtachan and Nekuchan Formations bears evidence for a certain continuity of the lithologic characteristics of the sandstones. The sharp lithologic contact between the formations reflects not a regional sedimentation hiatus but a shift of depositional settings from the upper parts of a delta to the deep shelf, caused by forced marine transgression. It is concluded that there was no long-term hiatus between the accumulation of the Imtachan and Nekuchan Formations. Images of the most characteristic species of bivalves and crinoids from the Imtachan Formation are presented.

Anthropogenic inputs are affecting freshwaters. Stable isotope ratios of nitrogen (δ15N) are useful to track anthropogenic pollution in food webs across different habitats, species and trophic levels. Cordoba province (Argentina) has serious problems of eutrophication and pollution in some of its freshwater reservoirs. To evaluate the different anthropogenic inputs in the three most important reservoirs in Cordoba: San Roque Lake (SRL), Los Molinos Lake (LML) and Rio Tercero Reservoir (RTR), δ15N was measured in water, plankton, shrimp (Palaemonetes argentinus) and fish (Odontesthes bonariensis) muscle samples. Results show that δ15N values of SRL samples (δ15N values between 14.9 and 20.0‰) are higher than those of the analogous samples from the other reservoirs, and denote a high influence of sewage discharge in this lake. The results show that the sewage isotopic signals in water were transferred to primary producers, then to mobile consumers, including fish. The findings of this study suggest that this reservoir is a source apparently not safe for food production, like edible fish. Finally, biota has proven to be a sensitive organism whose δ15N value can be used as bioindicator for pollution and human impact on the ecosystem in which it lives.

The aim of this work was to verify the usefulness of multielemental and isotopic fingerprint to differentiate the origin of milk samples from different areas, linking milk fingerprint with those corresponding to soil, water, and forage. Samples from four production areas in Argentina were analysed: 26 elements, δ2H, δ13C, δ15N and δ18O. Milk provenance was assessed using 16 variables (Na, Mg, Al, V, Co, Ni, As, Se, Rb, Sr, Mo, Hg, δ2H, δ18O, δ13C and K/Rb). Generalized Procrustes Analysis (GPA) demonstrated the consensus between soil, water, forage and milk, in addition to differences between studied areas. Canonical Correlation Analysis (CCA) demonstrated significant correlations between the milk-drinking water, milk-forage, and milk-soil. So far, we report a feasible method to establish the milk provenance, assessing the follow up from environmental matrixes (soil + water) to dairy products through the food web (forage) by a combined chemical-isotopic fingerprint.

In the central part of the External Dinarides in Plavno, Croatia, near Knin, a remarkably thick (927.5 m) Early Triassic depositional sequence was investigated. The Plavno sequence starts in the EarlyGriesbachian and ends with a continuous transition into the Anisian strata. A complete 13C isotope curve has been achieved and combined with conodonts, bivalves and ammonoids to establish and correlate stage and substage boundaries. The δ13C curve is consistent with former studies. It displays a general increase from the Griesbachian to a prominent maximum beyond the +8‰ amplitude around the Dienerian-Smithian boundary (DSB), followed by a steep and continuous decline to low, negative values in the Smithian. Around the Smithian-Spathian boundary (SSB) a steep rise to a second maximum occurred. It is followed by a saw-tooth shaped decline in the Spathian and a similar increase to a peak at the Spathian-Anisian boundary (SAB). Sedimentologically, the Plavno sequence is interpreted as having been deposited on an extensive epeiric ramp under long-term transgressive conditions, sharing depositional characteristics of both the epeiric platform and the carbonate ramp. The entire Plavno sequence was deposited above the storm-wave base and was storm influenced. Three informal members are differentiated: 1) the dolostone member (Early Griesbachian) ; 2) the siliciclastic member (red-coloured shale, siltstone, sandstone with oolitic/bioclastic grainstone intercalations), which can be further divided into lower, middle and upper intervals (Late Griesbachian, Dienerian and Smithian) ; and 3) the mudstone member (grey lime mudstones, marls and calcisiltites with common ammonoids and gastropods-Spathian). The Plavno sequence is compared with other western Tethyan sections. Observed differences stem from local controls on deposition in the overall shallow marine environment.

Recovery from the Late Permian mass extinction was slowed by continued environmental perturbations during the Early Triassic. Rapid fluctuations of the Early Triassic marine carbonate carbon isotope record indicate instability in the global carbon cycle, and recent δ 18 O apatite studies link elevated temperatures to the prolonged biotic recovery. High temperatures potentially caused enhanced continental weathering that was detrimental to marine ecosystems, but linking weathering rates to temperature has proven difficult. One proxy for weathering is the 87 Sr/ 86 Sr of marine carbonate; we present here an 87 Sr/ 86 Sr record from an upper Permian–lower Triassic succession near Zal, Iran, that is coupled to a δ 13 C carbonate record. An increase in the rate of 87 Sr/ 86 Sr rise from the Dienerian to the Smithian may be linked to elevated continental weathering rates caused by warming during the Smithian.

This paper is dedicated to the global correlation of the marine Permian-Triassic boundary layers based on some published and original data on the δ 13 Corg and δ 13 Ccarb values obtained for the section along the Suol Creek (Setorym River, southern Verkhoyansk region). The section includes six carbonisotope inter� vals readily distinguished in the corresponding curves obtained for several Permian and Triassic reference sec� tions in Eurasia and North America including palleontologically well substantiated sections of central Iran, Kashmir, and South China. This provides grounds for assuming the Permian-Triassic boundary's position in the Suol Creek section as being close to the carbonisoto pe minimum of Interval IV. In the light of new data, the upper part of the Upper Permian Changhsingian Stage in Siberia is proposed to correspond in range to the Otoceras concavum range zone, and the lower substage of the Lower Triassic Induan Stage, to the Tom� pophiceras pascoei and Wordieoceras decipiens zones. The Otoceras concavum Zone of the Verkhoyansk region in its new understanding is likely correlative with the upper Changhsingian Hypophiceras triviale Zone of Greenland. Carbonisotope intervals II, III, IV, and V defined in the Permian-Triassic boundary layers of the Verkhoyansk region, which are traceable in several reference sections of Eurasia and North America, evi� dently coincide with the period of some intensification of the volcanic activity in the initial late Changhsin� gian and with the first phases of extensive eruption of Siberian trappes in the terminal Changhsingian and ini� tial Induan ages. New data imply the probable survival of some ammonoid species from the superfamily Oto� ceratoidea after the mass extinction of organisms in the terminal Permian Epoch.