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With first joint fieldwork on Taymyr Peninsula during mid-1990s, a successful cooperation of German, Russian, and further international partners on permafrost and Quaternary palaeoenvironments in Siberia was started and resulted in extensive joint research for 3 decades. Studies of permafrost deposits and ground ice provided insights on past environmental and climatic changes, covering several hundreds of thousands of years into the past. They provide multi-proxy evidence for multiple glacial/interglacial cycles and different periods of past climate change or stability in Arctic land environments. Study objects were natural permafrost exposures along coastal sections, thaw slumps, and river banks, studied mostly during summers, complemented by permafrost cores from land, lake and sea ground drilled mostly in spring. Exposure geometry and stratigraphic horizon thickness have been surveyed using laser tachymetry, other measuring equipment, and drones. Based on multi-proxy analyses, mid- and late Quaternary periods were studied, resulting in >300 scientific papers. The approach includes geomorphic studies, various geochronological analyses, analysis of frozen sediments (for ice, carbon, nitrogen, and carbonate contents, grain-size parameters, magnetic susceptibility, heavy mineral compositions), ground ice (stable water isotopes, major ions) and of numerous fossil bioindicators, to reconstruct the Quaternary paleoenvironmental change. Oldest permafrost horizons were dated from the Batagay mega-thaw-slump (Yana Uplands) to about 650 ky with luminescence dating. Here and elsewhere, records of Eemian and Holocene interglacial periods, and environmental conditions associated with it were targeted. Many sites with late Pleistocene Yedoma Ice Complex have been explored. Lateglacial and Holocene warming induced enormous periglacial landscape changes by widespread permafrost degradation and substantial paleoecological changes. For vast Siberian areas where glacial records are not available, we aim on the establishment of permafrost as paleoclimatic archive, emphasizing peculiarities of permafrost age control and record resolution and stressing the great potential for understanding climate variability on glacial-interglacial timescales in Western Beringia.

Permafrost-agroecosystems encompass northern social-ecological systems which include both cultivation of arable permafrost-affected soils, and animal husbandry practices. These heterogeneous food and cultural systems are being affected by a warming climate. Examples include increasing opportunities for growing crops through longer growing seasons, as well as impacts on animals’ local and long-distance migratory movements and their food sources. Furthermore, climate change driven permafrost thaw and thaw accelerated by land clearance is rapidly changing the biophysical and socioeconomic aspects of these systems. Therefore, an international collaboration encompassing experts from North America, Europe and Asia is working on increasing our understanding of permafrost-agroecosystems and contributing to the adaptation, resilience, and sustainability strategy of these rapidly evolving systems. The International Permafrost Association Permafrost-Agroecosystem Action Group is composed of ~30 members from 7 countries. The objectives of our action group are to share knowledge and build networking capacities through meetings and webinar presentation as well as to collaborate on publications and produce the first geospatial dataset of permafrost-agroecosystems. Our poster presentation provides an overview of the group’s activities including providing case studies from a range of high-latitude and high-altitude areas as part of a group manuscript in preparation and an update on our mapping activities.

Permafrost degradation and organic matter decomposition in the terrestrial Arctic are strongly depending on soil temperatures. A factor that affects these temperatures is grazing and snow trampling by large herbivorous animals, as well as animal-induced changes in vegetation cover. We analysed samples taken from adjacent areas with different grazing intensities, both in a permafrost environment (Siberia) and seasonally frozen ground (norther Finland) for TOC, C/N ratio, d13C, bulk density and radiocarbon age. While in permafrost there was a strong increase in soil carbon storage with high grazing intensity, this effect is not visible in seasonally frozen ground. However, in both areas we observed massive changes in vegetation composition and structure, following the grazing gradient. We conclude that seasonally frozen ground allows for more intensive carbon relocation and mixing, which outweighs the effects animals have in the permafrost region but state that on permafrost, animals might efficiently be utilized to stabilise permafrost temperatures and reduce organic material decomposition.

In our study we examined the effects of large herbivorous animals on soil carbon storage in a permafrost landscape in northeastern Siberia. To assess the impact of those animals on the soil carbon storage, we examined soil profiles and permafrost cores from areas with different grazing intensities within landscape units, more specifically a drained thermokarst basin and the surrounding uplands. To do so, we chose our study sites in the Pleistocene Park near Chersky, as this area provides known animal densities and fenced areas, which allowed us to compare intensively grazed, extensively grazed, and non-grazed sites on a small spatial scale. We found significantly higher carbon (TOC) values at those sites with intensive animal grazing, compared to non-grazed sites, especially within the active layer. Also, vegetation was shifted on intensively grazed sites from shrubby tundra vegetation to grasslands. In addition, active layer depth was smaller on grazed sites. We conclude that the animals improve carbon storage and permafrost stability by changing the vegetation and removing or trampling down snow in winter, both of which led to colder ground conditions and hence reduced organic matter decomposition. This could be a hint to possible strategies to locally prevent permafrost thaw by rewilding or an intensification of animal husbandry in tundra areas.

We determine Hg concentrations of various deposits in Siberia’s deep permafrost and link sediment properties and Hg enrichment to establish a first Hg inventory of late Pleistocene permafrost down to a depth of 36 m below surface. As Arctic warming is transforming the ice-rich permafrost of Siberia, sediment is released and increases the flux of particulates to the Arctic shelf seas through thawing coasts, lakeshores, and river floodplains. Heavy metals within soils and sediments are also released and may increasingly enter Arctic waters and the biological food chain. High levels of mercury (Hg) have been reported from shallow soils across the Arctic. Rapid thawing is now mobilizing sediment from deeper strata, but so far little is known about Hg concentrations in deep permafrost. Here, forty-one samples from sediment successions at seven sites and of different states of permafrost degradation on Bykovsky Peninsula (northern Yakutian coast) and in the Yukechi Alas region (Central Yakutia) were analyzed for Hg, total carbon, total nitrogen, and total organic carbon as well as grain-size distribution, bulk density, and mass specific magnetic susceptibility. We show average Hg concentrations of 9.72 ± 9.28 μg kg−1 in the deep sediments, an amount comparable to the few previous Arctic studies existing, and a significant correlation of Hg content with total organic carbon, total nitrogen, grain-size distribution, and mass specific magnetic susceptibility. Hg concentrations are higher in the generally sandier sediments of the Bykovsky Peninsula than in the siltier sediments of the Yukechi Alas. The ratio of Hg to total organic carbon in this study is 2.57 g kg−1, including samples with very low carbon content. We conclude that many deep permafrost sediments, some of which have been frozen for millennia, contain elevated concentrations of Hg and the stock of Hg ready to be released by erosion is of significance for the Arctic ecosystem. The Hg mobilized may accumulate on the way to or in the shallow sea, and where it enters into active biogeochemical cycles of aquatic systems it may concentrate in food webs. Our study highlights the need for better understanding Hg stocks and Hg release from permafrost. Copyright

Since 1994, permafrost deposits of the Siberian Yedoma region have been in the focus of the joint Russian-German scientific cooperation in terrestrial Polar research (Figure 1). These studies focused on cryostratigraphic, geochemical, geochronological, and paleontological characteristics at more than 25 individual study sites of the late Pleistocene Yedoma Ice Complex in Siberia and provided a detailed insight into the paleoenvironments and paleoclimate for the westernmost part of Beringia. The multidisciplinary investigations resulted in new ideas and discussions in the ongoing scientific debate on the origin of Yedoma Ice Complex and the main periglacial processes involved in its formation (1,2,3). The Yedoma Ice Complex is an ice-rich type of permafrost deposit widely distributed across Beringia. The Ice Complex aggradation is mainly controlled by the growth of syngenetic ice wedge polygons contributing up to 60 vol% of the entire formation. The clastic sedimentation of ice-oversaturated Yedoma deposits with considerable organic matter content is further controlled by local conditions such as source rocks and periglacial weathering processes, paleotopography, and temporary surface stabilization with autochthonous peat growth and soil formation. Key processes include alluvial, fluvial, and niveo-aeolian transport (4) as well as accumulation in ponding waters and continued in-situ frost weathering over millennial time-scales. Important post-depositional processes affecting Yedoma deposits are solifluction, cryoturbation, and pedogenesis. Major joint Russian-German field studies were conducted on Taymyr Peninsula (5,6,7,8,9,10,11), along the western and central Laptev Sea coasts (12,13,14,15,16,17,18), in the Lena Delta (19,20,21,22), on islands of the New Siberian Archipelago (23,24,25,26,27,28), and the adjacent mainland (29). Further study sites were conducted in the Kolyma Lowland (30), the Yana Highlands (31,32), in the foothills of the Verkhoyan Mountains (33,34,35,36), and in Central Yakutia (37). Comprehensive sampling and further analytical work included not only the Yedoma Ice Complex itself but also included its stratigraphic context of older underlying sequences and younger overlying deposits. The latter often are subaerial or subaquatic deposits associated with late-Glacial to Holocene thermokarst dynamics that led to Yedoma degradation during the deglacial and Holocene warming of these regions (38,39,40). Figure 1: Joint Russian-German fieldwork sites in NE Siberia labeled with the year of expedition. Besides geomorphological and cryolithological studies, extensive paleo-ecological investigations were carried out on zoological (41,42,43,44,45) and botanic fossils (46,47,48,49,50,51) to derive quantitative and qualitative reconstructions late Pleistocene Beringian environments and climate conditions. New methods in geochronology were also tested (52,53,54,55). In addition to the sedimentary components of the frozen deposits, segregated ground ice and in particular the large syngenetic ice wedges of Yedoma Ice Complex were also studied as geochemical and stable isotope archives of paleoclimate (56,57,58, 59,60,61,62). In addition, a range of remote sensing methods in combination with GIS analyses (63,64,65) and geophysical surveys (66) were used for large-scale analyses of landscape changes associated with Yedoma Ice Complex degradation (67,68,69). In the last few years, an additional important focus has been on using modern biogeochemical methods of organic matter analysis to characterize the frozen organic matter in Yedoma Ice Complex deposits and for permafrost carbon pool calculations (70, 71,72,73,74,75,76,77) as well as microbiological studies (78) and genetic studies on fossil DNA (79,80). The rich body of scientific data and literature produced in Russian-German co-authorship within the more than 25 years of joint research on Yedoma Ice Complex represents an important cornerstone for understanding the Late Quaternary evolution of Siberian Yedoma regions, its role in the Earth System, and its feedbacks with climate and ecosystems. References 1. Schirrmeister, L., Dietze, E., Matthes, H., Grosse, G., Strauss, J., Laboor, S., Ulrich, M., Kienast, F., and Wetterich, S. (2020) The genesis of Yedoma Ice Complex permafrost – grain-size endmember modeling analysis from Siberia and Alaska, E&G Quaternary Sci. J., 69, 33–53, doi: 10.5194/egqsj-69-33-2020. 2. Schirrmeister, L., Froese, D., Tumskoy, V., Grosse,G., Wetterich, S. (2013.) Yedoma: Late Pleistocene ice-rich syngenetic permafrost of Beringia. In: Elias S.A. (ed.) The Encyclopedia of Quaternary Science 2nd edition, vol. 3, pp. 542-552. Amsterdam: Elsevier. 3. Schirrmeister, L., Kunitsky, V.V., Grosse, G., Wetterich, S., Meyer, H., Schwamborn, G., Babiy, O., Derevyagin, A.Y., and Siegert, C.: Sedimentary characteristics and origin of the Late Pleistocene Ice Complex on North-East Siberian Arctic coastal lowlands and islands - a review. Quaternary International 241, 3-25, doi: 10.1016/j.quaint.2010.04.004, 2011. 4. Kunitsky, V., Schirrmeister, L., Grosse, G., Kienast, F. (2002). Snow patches in nival landscapes and their role for the Ice Complex formation in the Laptev Sea coastal lowlands, Polarforschung, 70, 53-67, doi:10.2312/polarforschung.70.53. 5. Andreev, A. , Siegert, C. , Klimanov, V. A. , Derevyagin, A. Y. , Shilova, G. N. and Melles, M. (2002) Late Pleistocene and Holocene vegetation and climate changes in the Taymyr lowland, Northern Siberia Quaternary research, 57, pp. 138-150 . 6. Andreev, A. , Tarasov, P. E. , Siegert, C. , Ebel, T. , Klimanov, V. A. , Melles, M. , Bobrov, A. A. , Derevyagin, A. Y. , Lubinski, D. J. and Hubberten, H. W. (2003) Vegetation and climate changes on the northern Taymyr, Russia during the Upper Pleistocene and Holocene reconstructed from pollen records , Boreas, 32 (3), pp. 484-505 . 7. Chizhov, A. B. , Derevyagin, A. Y. , Simonov, E. F. , Hubberten, H. W. and Siegert, C. (1997) Isotopic composition of ground ice at the Labaz Lake region (Taymyr). Kriosfera Zemlii (Earth Cryoshere), 1, No 3, pp. 79-84 . (in Russian), 8. Derevyagin, A.Yu., Chizhov, A.B., Brezgunov, V.S., Siegert, C., Hubberten, H.-W., 1999.Isotopic composition of ice wedges of Cape Sabler (Lake Taymyr). Kriosfera Zemlii (Earth Cryosphere) 3/3, 41-49 (in Russian). 9. Kienast, F., Siegert, C., Dereviagin, A., Mai, H.D. Climatic implications of Late Quaternary plant macrofossil assemblages from the Taymyr Peninsula, Siberia, Global and Planetary Change, Volume 31, Issues 1–4, 265-281, 2001, https://doi.org/10.1016/S0921-8181(01)00124-2. 10. Kienel, U. , Siegert, C. and Hahne, J. (1999) Late Quarternary paeloenvironmental reconstruction from a permafrost sequence (Northsiberian Lowland, SE Taymyr Peninsula) - a multidisciplinary case study, Boreas, 28 (1), pp. 181-193 . 11. Siegert C., Derevyagin A.Y., Shilova G.N., Hermichen WD., Hiller A. (1999) Paleoclimatic Indicators from Permafrost Sequences in the Eastern Taymyr Lowland. In: Kassens H. et al. (eds) Land-Ocean Systems in the Siberian Arctic. Springer, Berlin, Heidelberg. 12. Bobrov, A.A., Müller, S., Chizhikova, N.A., Schirrmeister, L., Andreev, A.A.(2009).Testate Amoebae in Late Quaternary Sediments of the Cape Mamontov Klyk (Yakutia), Biology Bulletin, 36(4), 363-372. 13. Schirrmeister, L., Grosse, G., Kunitsky, V., Magens, D., Meyer, H., Dereviagin, A., Kuznetsova, T., Andreev, A., Babiy, O., Kienast, F., Grigoriev, M., Overduin, P.P., and Preusser, F.: Periglacial landscape evolution and environmental changes of Arctic lowland areas for the last 60,000 years (Western Laptev Sea coast, Cape Mamontov Klyk), Polar Research, 27(2), 249-272, doi: 10.1111/j.1751-8369.2008.00067.x, 2008. 14. Winterfeld, M., Schirrmeister, L., Grigoriev, M., Kunitsky, V.V., Andreev, A., and Overduin, P.P.: Permafrost and Landscape Dynamics during the Late Pleistocene, Western Laptev Sea Shelf, Siberia, Boreas 40(4), 697–713, doi: 10.1111/j.1502-3885.2011.00203.x, 2011. 15. Siegert, C., Schirrmeister, L., and Babiy, O.: The sedimentological, mineralogical and geochemical composition of late Pleistocene deposits from the ice complex on the Bykovsky peninsula, northern Siberia, Polarforschung, 70, 2000, 3-11, doi: 10.2312/polarforschung.70.3, 2002. 16. Schirrmeister, L., Siegert, C., Kuznetsova, T., Kuzmina, S., Andreev, A.A., Kienast, F., Meyer, H., and Bobrov, A.A.: Paleoenvironmental and paleoclimatic records from permafrost deposits in the Arctic region of Northern Siberia, Quaternary International, 89, 97-118, doi: 10.1016/S1040-6182(01)00083-0, 2002. 17. Schirrmeister, L., Siegert, C., Kunitzky, V.V., Grootes, P.M., and Erlenkeuser, H.: Late Quaternary ice-rich permafrost sequences as a paleoenvironmental archive for the Laptev Sea Region in northern Siberia, International Journal of Earth Sciences, 91, 154-167, doi: 10.1007/s005310100205, 2002. 18. Schirrmeister, L., Schwamborn, G., Overduin, P.P., Strauss, J., Fuchs, M.C., Grigoriev, M., Yakshina, I., Rethemeyer, J., Dietze, E., and Wetterich, S.: Yedoma Ice Complex of the Buor Khaya Peninsula (southern Laptev Sea), Biogeosciences 14, 1261-1283, doi: 10.5194/bg-14-1261-2017, 2017. 19. Schirrmeister, L., Kunitsky, V.V., Grosse, G., Schwamborn, G., Andreev, A.A., Meyer, H., Kuznetsova, T., Bobrov, A., and Oezen, D.: Late Quaternary history of the accumulation plain north of the Chekanovsky Ridge (Lena Delta, Russia) - a multidisciplinary approach, Polar Geography, 27(4), 277-319, doi: 10.1080/789610225, 2003. 20. Schirrmeister, L., Grosse, G. Schnelle, M., Fuchs, M., Krbetschek, M., Ulrich, M., Kunitsky, V., Grigoriev, M., Andreev, A. Kienast, F., Meyer, H., Klimova, I., Babiy, O., Bobrov, A., Wetterich, S., and Schwamborn, G.: Late Quaternary paleoenvironmental records from the western Lena Delta, Arctic Siberia, Palaeogeography, Palaeoclimatology, Palaeoecology 299, 175–196, doi: 10.1016/j.quascirev.2009.11.017, 2011. 21. Schwamborn, G., Rachold, V., and Grigoriev, M.N.: Late Quaternary sedimentation history of the Lena Delta, Quaternary International 89, 119–134, doi: 10.1016/S1040-6182(01)00084-2, 2002. 22. Wetterich, S., Kuzmina, S., Andreev, A.A., Kienast, F., Meyer, H., Schirrmeister, L., Kuznetsova, T., and Sierralta, M.: Palaeoenvironmental dynamics inferred from late Quaternary permafrost deposits on Kurungnakh Island, Lena Delta, Northeast Siberia, Russia, Quaternary Science Reviews, 27, 1523-1540, doi: 10.1016/j.quascirev.2008.04.007, 2008. 23. Andreev, A.A., Grosse, G., Schirrmeister, L., Kuzmina, S.A., Novenko, E.Yu., Bobrov, A.A., Tarasov, P. E., Kuznetsova, T.V., Krbetschek, M., Meyer, H., and Kunitsky, V.V.: Late Saalian and Eemian palaeoenvironmental history of the Bol'shoy Lyakhovsky Island (Laptev Sea region, Arctic Siberia), Boreas 33(4), 319-348, doi:10.1080/03009480410001974, 2004. 24. Andreev, A., Grosse, G., Schirrmeister, L., Kuznetsova, T.V., Kuzmina, S.A., Bobrov, A.A., Tarasov, P.E., Novenko, E.Yu., Meyer, H., Derevyagin, A.Yu., Kienast, F., Bryantseva, A., and Kunitsky, V.V.: Weichselian and Holocene palaeoenvironmental history of the Bol’shoy Lyakhovsky Island, New Siberian Archipelago, Arctic Siberia, Boreas 38(1), 72–110, doi: 10.1111/j.1502-3885.2008.00039.x, 2009. 25. Wetterich, S., Rudaya, N., Meyer, H., Opel, T., and Schirrmeister, L.: Last Glacial Maximum records in permafrost of the East Siberian Arctic, Quaternary Science Reviews 30, 3139-3151, doi: 10.1016/j.quascirev.2011.07.020, 2011. 26. Wetterich, S., Rudaya, N., Andreev, A.A., Opel, T., Schirrmeister, L., Meyer, H., and Tumskoy, V.: Ice Complex formation in arctic East Siberia during the MIS3 Interstadial, Quaternary Science Reviews 84: 39-55, doi:. 10.1016/j.quascirev.2013.11.009, 2014. 27. Wetterich, S.; Tumskoy:V.E., Rudaya, N., Kuznetsov, V., Maksimov, F., Opel T. , Meyer H., Andreev, A.A., Schirrmeister, L (2016) Ice Complex permafrost of MIS5 age in the Dmitry Laptev Strait coastal region (East Siberian Arctic). Quaternary Science Reviews, 147:298-31, doi.org/10.1016/j.quascirev.2015.11.016. 28. Wetterich, S., Rudaya, N., Kuznetsov V., Maksimov, F., T. Opel, Meyer, H., Guenther, F., Bobrov, A., Raschke, E., Zimmermann, H., Strauss, J., Fuchs, M.C., Schirrmeister, L. (2019) Recurrent Ice Complex formation in arctic eastern Siberia since about 200 ka. Quaternary Research 92 (2); 530-548, doi.org/10.1017/qua.2019.6. 29. Wetterich, S., Schirrmeister, L., Andreev A. A., Pudenz, M., Plessen, B, Meyer, H., Kunitsky, V. V. (2009). Eemian and Late Glacial/Holocene palaeoenvironmental records from permafrost sequences at the Dmitry Laptev Strait (NE Siberia, Russia), Palaeogeography, Palaeoclimatology, Palaeoecology 279: 73-95 doi:10.1016/j.palaeo.2009.05.002. 30. Strauss, J., Schirrmeister, L., Wetterich, S., Borchers, A, and Davydov S.P.: Grain-size properties and organic-carbon stock of Yedoma Ice Complex permafrost from the Kolyma lowland, northeastern Siberia. GBC. 26: GB3003, doi: 10.1029/2011GB004104, 2012. 31. Ashastina, K., Schirrmeister, L., Fuchs M., and Kienast F.: Palaeoclimate characteristics in interior Siberia of MIS 6–2: first insights from the Batagay permafrost mega-thaw slump in the Yana Highlands, Clim. Past, 13, 795–818, doi: 10.5194/cp-13-795-2017, 2017. 32. Kunitsky, V.V., Syromyatnikov, I.I., Schirrmeister, L., Skachkov, Yu.B., Grosse, G., Wetterich, S., and Grigoriev, M.N.: Ice-rich permafrost and thermal denudation in the Kirgillyakh area, Kriosfera Zemli. 17(1), 56-68, 2013 (in Russian). 33. Popp, S., Diekmann,B., Meyer, H., Siegert, C.,Syromyatnikov, I., Hubberten, H.-W. Palaeoclimate Signals as Inferred from Stable-isotope Composition of Ground Ice in the Verkhoyansk Foreland, Central Yakutia. Permafrost and Periglac. Process. 17: 119–132 (2006) DOI: 10.1002/ppp.556 34. Popp, S., Belolyubsky, I., Lehmkuhl, F., Prokopiev, A., Siegert, C., Spektor, V., Stauch, G., Diekmann,B. Sediment provenance of late Quaternary morainic, fluvialand loess-like deposits in the southwestern VerkhoyanskMountains (eastern Siberia) and implications for regionalpalaeoenvironmental reconstructions. Geol. J.42: 477–497 (2007), DOI: 10.1002/gj.1088 35. Siegert, C. , Sergeyenko, A. I. and Schirrmeister, L. (2017) Late Quaternary Deposits of the Northern Verkhoyansk Mountains: Geochronology and Questions of their Genesis (in Russian), Bulletin of the Commission for Study of the Quaternary = БЮЛЛЕТЕНЬ КОМИССИИ ПО ИЗУЧЕНИЮ ЧЕТВЕРТИЧНОГО ПЕРИОДА, 75 , pp. 100-112 . 36. Siegert, C. , Stauch, G. , Lehmkuhl, F. , Sergeyenko, A. I. , Diekmann, B. , Popp, S. and Belolyubsky, I. N. (2007) Development of glaciation in the Verkhoyansk Range and its foreland during the Pleistocene: Results of new investigations., Regionalnaya Geologiya i Metallogeniya (Regional Geology and Metallogeny), No. 30-31(in Russian)., 222 . 37. Ulrich, M., Morgenstern, A., Günther, F., Reiss, D. Bauch, K. E., Hauber, E., Rössler, S. and Schirrmeister, L. (2010) Thermokarst in Siberian ice-rich permafrost: Comparison to asymmetric scalloped depressions on Mars, Journal of Geophysical Research, 115, E10009 . doi:10.1029/2010JE003640 , 38. Morgenstern, A. , Grosse, G. , Günther, F. , Fedorova, I. and Schirrmeister, L. (2011): Spatial analyses of thermokarst lakes and basins in Yedoma landscapes of the Lena Delta. The Cryosphere, 5(4), 849–867, doi:10.5194/tc-5-849-2011. 39. Morgenstern, A. , Ulrich, M. , Günther, F. , Roessler, S. , Fedorova, I. V. , Rudaya, N. A. , Wetterich, S. , Boike, J. and Schirrmeister, L. (2013). Evolution of thermokarst in East Siberian ice-rich permafrost: A case study, Geomorphology, 201 , 363-379. doi:10.1016/j.geomorph.2013.07.011 40. Biskaborn, B. , Herzschuh, U. , Bolshiyanov, D. Y. , Schwamborn, G. and Diekmann, B. (2013) Thermokarst Processes and Depositional Events in a Tundra Lake, Northeastern Siberia, Permafrost and Periglac. Process.24: 160–174 doi:https://doi.org/10.1002/ppp.1769, 41. Kuznetsova, T. V. , Sulerzhitsky, L. D. , Andreev, A. , Siegert, C. , Schirrmeister, L. and Hubberten, H. W. (2003) Influence of Late Quaternary paleoenvironmental conditions on the distribution of mammals fauna in the Laptev Sea region , Occasional Papers in Earth Sciences, 5 , pp. 58-60 . 42. Kuznetsova T.V., Tumskoy V.E., Schirrmeister L., Wetterich S., (2019.) Paleozoological characteristics of the Late Neo-Pleistocene - Holocene sediments of Bykovsky Peninsula, Northern Yakutia (Палеозоологическая характеристика поздненеоплейстоценовых – голоценовых отложений Быковского Полуострова (Северная Якутия). Zoological Journal 98(11), 1268-1290. Special issue in honor of Andrey Sher. (in Russian) doi: 10.1134/S0044513419110102. 43. Bobrov, A. A. , Andreev, A. , Schirrmeister, L. and Siegert, C. (2004) Testate amoebae (Protozoa: Testacea) as bioindicators in the Late Quaternary deposits of the Bykovsky Peninsula, Laptev Sea, Russia , Palaeogeography palaeoclimatology palaeoecology, 209 , pp. 165-181 . doi:https://doi.org/10.1016/J.PALAEO.2004.02.012 44. Wetterich, S., Schirrmeister, L., Pietrzeniuk, E. (2005). Freshwater ostracodes in Quaternary permafrost deposits from the Siberian Arctic, Journal of Paleolimnology, 34, 363-376. doi:10.1007/s10933-005-5801-y 45. Müller, S., Bobrov, A. A., Schirrmeister, L., Andreev, A. A., Tarasov, P. E. (2009). Testate amoebae record from the Laptev Sea coast and its implication for the reconstruction of Late Pleistocene and Holocene environments in the Arctic Siberia, Palaeogeography, Palaeoclimatology, Palaeoecology 271(3-4), 301-315. doi:10.1016/j.palaeo.2008.11.003 46. Andreev, A.A., Schirrmeister, L., Siegert, C., Bobrov, A.A., Demske, D., Seiffert, M., Hubberten, H.-W. (2002). Paleoenvironmental changes in Northeastern Siberia during the Late Quaternary - evidence from pollen records of the Bykovsky Peninsula, Polarforschung, 70, 13-25, doi:10.2312/polarforschung.70.13. 47. Andreev, A.A.; Schirrmeister, L.; Tarasov , P.E.; Ganopolski , A.; Brovkin V.; Siegert, C.; Hubberten, H.-W. (2011). Vegetation and climate history in the Laptev Sea region (arctic Siberia) during Late Quaternary inferred from pollen records. Journal of Quaternary science reviews. 30, 2182-2199 doi:10.1016/j.quascirev.2010.12.026. 48. Kienast, F. , Schirrmeister, L. , Siegert, C. and Tarasov, P. (2005) Palaeobotanical evidence for warm summers in the East Siberian Arctic during the last cold stage, Quaternary Research, 63 (3), pp. 283-300. doi:https://doi.org/10.1016/j.yqres.2005.01.003 , 49. Kienast, F., Tarasov, P., Schirrmeister, L., Grosse, G., Andreev, A.A. (2008). Continental climate in the East Siberian Arctic during the last interglacial: implications from palaeobotanical records, Global and Planetary Change, 60(3/4), 535-562. doi:10.1016/j.gloplacha.2007.07.004 50. Kienast, F., Wetterich, S., Kuzmina, S., Schirrmeister, L., Andrev, A., Tarasov, P., Nazarova, L., Kossler, A., Frolova, A., Kunitsky, V. V.(2011) Paleontological records indicate the occurrence of open woodlands in a dry inland climate at the present-day Arctic coast in western Beringia during the last interglacial. Quaternary Science Reviews 30: 2134-2159, doi:10.1016/j.quascirev.2010.11.024. 51. Palagushkina, O.V., Wetterich, S., Schirrmeister, L., Nazarova, L.B. (2017) Modern and fossil diatom assemblages from Bol'shoy Lyakhovsky Island (New Siberian Archipelago, Arctic Siberia). Contemporary Problems of Ecology, 10, (4), 380–394. doi: 10.1134/S1995425517040060. 52. Gilichinsky, D. A. , Nolte, E., Basilyan, A.E., Beer, J., Blinov, A., Lazarev, V., Kholodov, A., Meyer, H., Nikolsky, P.A., Schirrmeister, L., Tumskoy, V. (2007). Dating of syngenetic ice wedges in permafrost with 36Cl and 10Be, Quaternary science reviews. 26, 1547-1556. doi:10.1016/j.quascirev.2007.04.004 53. Blinov A.V., Beer J., Tikhomirov D.A., Schirrmeister L., Meyer H., Abramov A.A., Basylyan A.E., Nikolskiy P.A., Tumskoy V.E., Kholodov A.L., Gilichinsky D.A. (2009) Permafrost dating with the cosmogenic radionuclides ( Report 1) (= Датирование многолетнемерзлых пород с помощью космогенных радионуклидов (сообщение 1). Kriosfera Zemli 13,( 2), 3-15 (in Russian). 54. Blinov, A., Alfimov, V., Beer, J., Gilichinsky, D., Schirrmeister, L., Kholodov, A., Nikolskiy, P., Opel, T., Tikhomirov, D., Wetterich, S.(2009).36Cl/Cl ratio in ground ice of East Siberia and its application for chronometry, Geochemistry, Geophysics, Geosystems (G3). 10(1), doi: 10.1029/2009GC002548. 55. Schirrmeister, L., Oezen, D., Geyh, M.A. (2002). 230Th/U dating of frozen peat, Bol'shoy Lyakhovsky Island (North Siberia), Quaternary research, 57, 253-258. doi:10.1006/qres.2001.2306. 56. Meyer, H. , Derevyagin, A. Y. , Siegert, C. and Hubberten, H. W. (2002) Paleoclimate studies on Bykovsky Peninsula, North Siberia - hydrogen and oxygen isotopes in ground ice , Polarforschung 70:, pp. 37-51 . 57. Derevyagin, A. Y., Chizhov, A. , Meyer, H. , Opel, T. , Schirrmeister, L. and Wetterich, S. (2013). Isotopic composition of texture ices, Laptev Sea coast , Kriosfera Zemlii (Earth Cryosphere), XVII (3), pp. 27-34 (in Russian). 58. Meyer, H. , Derevyagin, A. Y. , Siegert, C. , Schirrmeister, L. and Hubberten, H. W. (2002) Paleoclimate reconstruction on Big Lyakhovsky Island, North Siberia - Hydrogen and oxygen isotopes in ice wedges , Permafrost and periglacial processes, 13 , pp. 91-105 . 59. Opel, T., Dereviagin, A., Meyer, H., Schirrmeister, L., Wetterich, S. (2010).Paleoclimatic information from stable water isotopes of Holocene ice wedges at the Dmitrii Laptev Strait (Northeast Siberia), Permafrost and Periglacial Processes. 22 (1), 84-100, doi:10.1002/ppp.667. 60. Opel, T., Wetterich, S., Meyer, H., Dereviagin, A.Yu., Fuchs, M.C., and Schirrmeister, L.: Ground-ice stable isotopes and cryostratigraphy reflect late Quaternary palaeoclimate in the Northeast Siberian Arctic (Oyogos Yar coast, Dmitry Laptev Strait). Clim. Past, 13, 587–611, 2017, doi: 10.5194/cp-13-587-2017, 2017. 61. Opel, T., Murton, J. B., Wetterich, S., Meyer, H., Ashastina, K., Günther, F., Grotheer, H., Mollenhauer, G., Danilov, P. P., Boeskorov, V., Savvinov, G. N., Schirrmeister, L. (2019) Past climate and continentality inferred from ice wedges at Batagay megaslump in the Northern Hemisphere's most continental region, Yana Highlands, interior Yakutia, Clim. Past, 15, 1443–1461, doi: 10.5194/cp-15-1443-2019. 62. Ulrich, M., Grosse, G., Strauss, J. and Schirrmeister, L. (2014): Quantifying wedge-ice volumes in yedoma and thermokarst basin deposits, Permafrost and Periglacial Processes 25, 151–161. doi:10.1002/ppp.1810. 63. Grosse, G., Schirrmeister, L., Siegert, C., Kunitsky, V.V., Slagoda, E.A., Andreev, A.A., and Dereviagyn, A.Y.: Geological and geomorphological evolution of a sedimentary periglacial landscape in Northeast Siberia during the Late Quaternary, Geomorphology, 86(1/2), 25-51, doi:10.1016/j.geomorph.2006.08.005, 2007. 64. Grosse, G., Schirrmeister, L., Kunitsky, V. V., Hubberten, H. -W. (2005). The Use of CORONA Images in Remote Sensing of Periglacial Geomorphology: An Illustration from the NE Siberian Coast, Permafrost and periglacial processes, 16, 163-172. doi:10.1002/ppp.509 65. Grosse, G., Robinson, J.E., Bryant, R., Taylor, M.D., Harper, W., DeMasi, A., Kyker-Snowman, E., Veremeeva, A., Schirrmeister, L., Harden, J. (2013). Distribution of late Pleistocene ice-rich syngenetic permafrost of the Yedoma Suite in east and central Siberia, Russia. U.S. Geological Survey Open File Report 2013-1078, 37p. 66. Schennen, S., Tronicke, J., Wetterich, S., Allroggen, N., Schwamborn, G., Schirrmeister, L. (2016) 3D GPR imaging of Ice Complex deposits in northern East Siberia, Geophysics 81(1), WA185-WA192, doi: 10.1190/GEO2015-0129.1. 67. Günther, F. , Overduin, P. P. , Yakshina, I. A. , Opel, T. , Baranskaya, A. V. and Grigoriev, M. N. (2015) Observing Muostakh disappear: permafrost thaw subsidence and erosion of a ground-ice-rich island in response to arctic summer warming and sea ice reduction , The Cryosphere, 9 (1), pp. 151-178 . doi.org/10.5194/tc-9-151-2015 68. Günther, F. , Overduin, P. P. , Sandakov, A. V. , Grosse, G. and Grigoriev, M. N. (2013) Short- and long-term thermo-erosion of ice-rich permafrost coasts in the Laptev Sea region, Biogeosciences, 10 , pp. 4297-4318 . doi:https://doi.org/10.5194/bg-10-4297-2013 69. Overduin, P. P. , Strzelecki, M. C. , Grigoriev, M. N. , Couture, N. , Lantuit, H. , St-Hilaire-Gravel, D. , Günther, F. and Wetterich, S. (2013) Coastal changes in the Arctic, Geological Society of London Special Publication, 388 . doi:https://doi.org/10.1144/SP388.13 70. Strauss J., Schirrmeister L., Grosse G., Wetterich S., Ulrich M., Herzschuh U., H.-W.Hubberten (2013). The Deep Permafrost Carbon Pool of the Yedoma Region in Siberia and Alaska. GRL 40, 6165-6170. doi 10.1002/2013GL058088. 71. Strauss, J., Schirrmeister, L., Mangelsdorf, K., Eichhorn, L., Wetterich S., and Herzschuh U.: Organic matter quality of deep permafrost carbon - a study from Arctic Siberia. Biogeosciences, 12, 2227–2245, doi: 10.5194/bg-12-2227-2015, 2015. 72. Strauss,J., Schirrmeister, L., Grosse, G., Fortier, D., Hugelius, G., Knoblauch, C., Romanovsky, V., Schädel, C., Schneider von Deimling, T., Schuur, E.A.G., Shmelev, D., Ulrich, M.,, Veremeeva, A. (2017). Deep Yedoma permafrost: A synthesis of depositional characteristics and carbon vulnerability. Earth-Science Reviews 172, 75-86, doi: 10.1016/j.earscirev.2017.07.007. 73. Stapel, J. G., L. Schirrmeister, P. P. Overduin, S. Wetterich, J. Strauss, B. Horsfield, and K. Mangelsdorf (2016), Microbial lipid signatures and substrate potential of organic matter in permafrost deposits - implications for future greenhouse gas production, J. Geophys. Res. Biogeosci., 121, doi: 10.1002/2016JG003483. 74. 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(2019) Glycerol dialkyl glycerol tetraethers (GDGTs) in high latitude Siberian permafrost: Diversity, environmental controls, and implications for proxy applications. Organic Geochemistry 136, 103888, doi: 10.1016/j.orggeochem.2019.06.009. 78. Mitzscherling, J., Horn, F., Winterfeld, M., Mahler, L., Kallmeyer, J., Overduin, P.P., Schirrmeister, L., Winkel, M., Grigoriev, M.N., Wagner, D., Liebner, S. (2019) (6bial community composition and abundance after millennia of submarine permafrost warming. Biogeosciences, 16, 3941–3958, doi: 10.5194/bg-16-3941-2019. 79. Zimmermann, H.H., Raschke, E., Epp, L.S., Stoof-Leichsenring, K.R., Schirrmeister, L., Schwamborn, G., Herzschuh, U. (2017). The history of tree and shrub taxa on Bol’shoy Lyakhovsky Island (New Siberian Archipelago) since the last interglacial uncovered by sedimentary ancient DNA and pollen data. Genes 8(10), E273; doi: 10.3390/genes8100273. 80. Zimmermann, H.H., Raschke, E., Epp, L.S., Stoof-Leichsenring, K., Schwamborn, G., Schirrmeister, L., Overduin, P.P., Herzschuh, U. (2017) Sedimentary ancient DNA and pollen reveal the composition of plant organic matter in Late Quaternary permafrost sediments of the Buor Khaya Peninsula (north-eastern Siberia). Biogeosciences 14, 575-596, doi:10.5194/bg-14-575-2017

The late Pleistocene ice-rich Yedoma permafrost is extremely sensitive to Arctic warming. Warming air temperatures, decreasing sea ice extent lead to an increasing degradation of the Yedoma permafrost and thus to a greater sediment input from coastal shorelines and river floodplains to the Laptev Sea. Thus, so far freeze-locked sediments and any potentially hazardous contaminants contained in them are entering Arctic waters and the biological food chain. Shallow (down to

The distinguishing feature of permafrost in the Arctic is the presence of a large amount of ice below the earth surface. Thermal degradation and subsequent destabilization of ground ice rich terrain cause thaw subsidence. Because these phenomena are hard to detect, they have received not much attention, despite their potentially global significance through the permafrost carbon feedback and implications for active layer thickness monitoring. Clearly, however, detailed local inventories are required to calibrate regional targeted long and short-term assessments for measuring surface deformation due to permafrost thaw. We analyze time series of repeat terrestrial laser scanning (rLiDAR) for quantification of land surface lowering on a tundra upland in the Teshekpuk Lake Special Area on Alaska´s North Slope. Here, considerable negative surface elevation changes have been detected over two years from 2015 to 2017. Spatial patterns of land elevation changes indicate that ice wedge polygon troughs are particularly prone to subsidence. This highlights the vulnerability of arctic tundra lowlands with ice-rich permafrost close to the surface.

Die Chronische Lymphatische Leukämie gehört zu den Non-Hodgkin-Lymphomen der B-Zell-Reihe. Ihre durchschnittliche Inzidenz liegt bei 4/100.000/Jahr und ist mit steigendem Alter zunehmend. Im 8. Lebensjahrzehnt liegt sie bei 30/100.000 Neuerkrankungen pro Jahr und ist damit die[zum vollständigen Text gelangen Sie über die oben angegebene URL], 44. gemeinsamen Tagung der Bayerischen Urologenvereinigung und der Österreichischen Gesellschaft für Urologie und Andrologie

Das Urothelkarzinom der Harnblase ist mit 16000 Neuerkrankungen pro Jahr in Deutschland der zweithäufigste Urogenitaltumor insgesamt und der häufigste bei Frauen. Bei Diagnosestellung sind 15% bereits metastasiert. Typische Metastasierungslokalisationen sind Knochen, Leber, Gehirn und[zum vollständigen Text gelangen Sie über die oben angegebene URL], 44. gemeinsamen Tagung der Bayerischen Urologenvereinigung und der Österreichischen Gesellschaft für Urologie und Andrologie

Die Kalziphylaxie ist mit 24 bis 35 dokumentierten Fällen pro Jahr im deutschen Kalziphylaxieregister eine seltene und schmerzhafte Erkrankung mit begrenzten therapeutischen Optionen. Es kommt zu Wundheilungsstörungen aufgrund einer Mediasklerose kleiner Arterien und Arteriolen. Bei Superinfektionen[zum vollständigen Text gelangen Sie über die oben angegebene URL], 44. gemeinsamen Tagung der Bayerischen Urologenvereinigung und der Österreichischen Gesellschaft für Urologie und Andrologie

The unique feature of permafrost in the Arctic is the presence of a large amount of ice below the earth surface. Thermal degradation and subsequent permafrost destabilization causes thaw subsidence and thermokarst development. Because these processes are difficult to detect due to the lack of timely and accurate elevation datasets they have received not much attention, despite their potentially global significance through the permafrost carbon feedback. Thanks to remote sensing pioneering works in Alaska and Siberia, widespread thaw subsidence has been documented and is increasingly perceived as a potentially widespread permafrost landscape response to contemporary climate change. Clearly, however, detailed local inventories are required to calibrate regional long and short-term assessments for measuring surface deformation due to permafrost thaw. The objective of our study is to analyze time series of repeat terrestrial, air-, and space borne laser scanning (rLiDAR) for quantification of land surface lowering due to permafrost thaw, which is poorly resolved in terms of recent landscape development in the Arctic. Our work aims at finding commonalities and differences of change or no change on ground-ice-rich primary surfaces that are preserved as uplands, which cover 15 to 20% of the Teshekpuk Lake Special Area on the Arctic Coastal Plain of northern Alaska. Our approach focuses on quantifying modern thaw subsidence and thermokarst rates with high spatial resolution data over several decades as well as high temporal resolution data of inter-annual intervals. Multi-annual measurements of rLiDAR over Arctic Alaska have been made by aircraft in 2016 and in 2015+2017 through on-site surveys during field expeditions. These in situ data serve as a basis for large scale surface change assessments using time series of photogrammetrically derived elevation data from very high resolution historical aerial photographs and modern satellite imagery. The synergistic data fusion approach enhances permafrost degradation monitoring and better resolves surface deformation associated with thaw subsidence. The novel datasets also provide insights into previously unrecognized patterns of rapid permafrost thaw and related interconnections.