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This paper presents sedimentological and paleobotanical studies of the deposits from Last Glaciation (Late Nemunas, Late Weichselian) in the middle reaches of the River Nemunas in southern Lithuania. Spores, pollen, and other palynomorphs in the intercalated sediments between the diamicton (glacial till) beds were analyzed, and the paleogeographical and paleoclimatic conditions of their sedimentation were assessed using the modern analog technique (MAT). The two till layers from the Last Glaciation, characterized by significant differences in their composition, testify to a difference in glacier movement paths in the region. The continuous sedimentation process between glacial tills provides evidence of global climate changes during the Last Glaciation and the restructuring of glacial lobes during deglaciation in the southeastern part of the Scandinavian Ice Sheet. The sedimentation process and vegetation composition bear witness to an open landscape of steppe-tundra, scattered wooded areas, and the emergence of thermophilic vegetation afterward, suggesting increased annual temperatures and higher humidity. The available data enable the identification of the Balbieriškis interstage period within the Late Nemunas Glaciation (Upper Nemunas Formation) between the Grūda and Baltija stages (Grūda and Baltija subformations) in the regional Quaternary stratigraphic scheme. This period correlates with the Marine Isotope Stage 2 (MIS 2). [ABSTRACT FROM AUTHOR]

The paper presents new data and reviews previously obtained results on the late glacial to Holocene history of peatlands in the southern part of the Baikal region under conditions of regional climate changes. To better understand climate signals, we have combined vegetation and geochemical variation data in 4.6 m thick peat deposits in the Vydrino bog located on the Tankhoi piedmont plain south of Lake Baikal. The territory has been swamped since 13.1 cal ka BP when the peatland started developing as a fen upon a sedimentary substrate. The 13.1–9.5 cal kyr climate record included two events of warming separated by an excursion of dry cold climate. Warming continued till 9.0 cal ka BP and eutrophic peat formation occurred in favorable temperature and moisture conditions. Another warming episode between 9.0 and 8.4 cal ka BP ended up with the Holocene climate optimum while the bog became mesotrophic. About 7.3–6.5 cal ka BP, the temperature and moisture inputs were no longer optimal for fir and spruce forests in the Vydrino area, which led to dramatic changes in landscape and vegetation. The wet and warm climate gradually became drier and colder from 6.5 to 2.3 cal ka BP, with a brief warm excursion about 5.5–5.3 cal ka BP. The peat deposition was interrupted in a cold climate from ∼2.3 cal ka BP to ∼0.7 cal ka BP, and the bog became oligotrophic afterwards. The newly obtained data allowed us to compare the paleoclimatic indicators available for the south Baikal region to determine their compatibility and inconsistency. In addition, we provide a general view to the quality of the climate and environmental reconstructions in the Baikal region by comparison of the data on its peatland study. [ABSTRACT FROM AUTHOR]

The variability and dynamics of the Asian monsoon (AM, hereafter indicates both of the summer and winter monsoons.) at orbital and millennial timescales has attracted wide interest. Chinese loess deposits, covering an area of ~500 × 103 km2 and with a thickness of several tens to more than three hundred meters, is an ideal continental archive to reconstruct AM variations during the Quaternary epoch. Over the past thirty years, since the earliest paper published in an international journal that linked the Asian monsoon and Chinese loess deposits, many studies have been undertaken focusing on this research topic. These results have greatly deepened our understanding of the variations of the AM climate and their driving mechanisms during the past ~2.6 Myr. In this paper, we emphasize recent progress on the AM variability and dynamics revealed by Chinese loess records; in particular, we discuss the reliability and precision of the timescale and the monsoon proxy indicators for the loess-paleosol sequences, which are two fundamental aspects for understanding AM behavior. We analyze what we know and discuss what we do not know about the AM. We refine the timescale for the typical loess-paleosol sequence in the central Chinese Loess Plateau (CLP), which can be used as a new timescale to study palaeoclimate and palaeoenvironmental changes in the monsoonal Asia. We conclude that low-latitude insolation changes induced by precession, and global ice volume, temperature at high-latitudes, as well as sea-level changes forced variations of the AM at orbital time scales. High-latitude cooling events and low-latitude hydroclimate process at millennial time scales, such as climate changes associated with Heinrich events and Dansgaard-Oeschger cycles in Northern Atlantic and Greenland, have also modulated AM variability. We suggest that high-latitude forcing of AM variations occurs through ocean and atmospheric circulation linkages, although the roles of atmospheric CO 2 , ocean and vegetation feedbacks need further investigation. In future study, high-resolution independent dating, novel proxy indices and transient numerical simulations are still basic tools to understand the loess deposition and AM variations that require considerably more work. Issues such as reliable spatial comparison and regional linkages of records (dependent on precise and accurate numerical chronologies), and quantitative reconstruction of the AM variations, should be given priority in the study the past climate change in Asia, and low-latitude hydroclimate process. [ABSTRACT FROM AUTHOR]

On shorter time scales, the karst carbon cycle coupled with photosynthesis, is a potential carbon sink. The surface water biological carbon pump (BCP) plays an important role by transforming dissolved inorganic carbon (DIC) to organic carbon (OC), forming a stable carbon sink through a series of biogeochemical processes on shorter timescales (i.e., years to thousands of years). A comprehensive understanding of the karst carbon sink (KCS) is important in understanding its role in the global carbon budget and carbon neutrality. In this paper, we review the current progress and prospect future research of KCS. The world is facing a quick change in climate and rapid variation in land-use, so the interaction mechanism between the above two and KCS needs to be further understood. Manual intervention to increase KCS also deserves attention. Meanwhile, due to the complexity of the karst system and karst carbon cycle, a comprehensive (water, rock, soil, atmosphere, biology) karst carbon cycle monitoring system needs to be established, integrating different types of carbon sink (e.g., soil, forest, karst) under a research framework. An in-depth understanding of these aspects will help KCS better serve the sustainable development of human society. [ABSTRACT FROM AUTHOR]

The Lateglacial period is marked by strong changes in environment and climate in Europe, associated to the different steps of the deglaciation. This paper aims to reconstruct the vegetation and climate changes from the deglaciation to the early Holocene (15.2–10.8 ka cal BP) in Western Europe. Pollen investigations are performed at a centennial resolution on a sedimentary core from the Lapsou peat bog (Cantal, France). The chronology is well constrained from three radiocarbon dates and a double tephra layer. The pollen record and quantitative climate reconstructions evidence strong changes associated with the Lateglacial period, in agreement with the regional vegetation and climate dynamics. At the onset of Lateglacial Interstadial (14.5–14.1 ka cal BP), a Juniperus - Betula succession is attributed to the Bølling. Associated climate reconstructions indicate a winter warming of 10 °C and precipitations above 1000 mm. A development of Pinus forests is then evidenced for the Allerød, for which rather constant warm conditions and lower precipitations (drop of 200 mm) are reconstructed. A two-phase pattern characterizes the Younger Dryas (12.6–11.5 ka cal BP): after a first phase with rather constant vegetation and climate conditions compared to the Allerød, a more steppic vegetation developed from 12.2 ka cal BP, indicating a marked cooling and a pronounced aridity (precipitations around 400 mm). Finally, the reconstruction of a cool deciduous forest dominated by Betula and temperate climate conditions defines the early Holocene. A comparison with chironomid-inferred reconstructions of July temperature from the close La Roustière site allows to support pollen-inferred climate quantifications, also showing the interest of applying multi-proxy approach in palaeo-environmental studies. [ABSTRACT FROM AUTHOR]

The sedimentary sequence of La Narce du Béage Basin is one of the few natural archives covering the last 18 ka cal. BP in the French Massif Central. This paper focuses on the palaeoecological reconstruction of environmental and climatic changes affecting this shallow periglacial lake from the Late-Glacial to the Early Holocene. After field surveys and geophysical mapping, two cores (cores A and D) were extracted and dated. Plant macrofossils, pollen, non-pollen palynomorphs (NPPs) and diatom assemblages were compared within the cores to study vegetation, temperature, pH, water level and ice cover changes through time. During the Oldest Dryas (18–14.75 ka cal. BP), climatic conditions were the coldest with a short ice-free season allowing the development of periphytic diatoms only (ecologically comparable to Arctic ones). A cold and dry steppe landscape – exposed to severe erosion – comprised an herbaceous and shrub flora (e.g. Artemisia , Chenopodiaceae, Helianthemum, Ephedra, Hippophaë, Juniperus). Animal presence is suggested by coprophilous fungi. Periphytic diatoms and allochtonous pollen (Cedrus) underline windy conditions, and the possible erosion of neo-formed soils. Then, during the Bølling-Allerød interstadial (14.75–12.7 ka cal. BP), the ice-free season increased and some trees/shrubs (Salix, Betula and Juniperus) established locally within open grasslands. During the Younger Dryas (12.7–11.7 ka cal. BP) cooler conditions favoured steppe taxa again (Helianthemum, Achillea, Artemisia , Caryophyllaceae, Ranunculaceae) and erosion increased. The ice cover on the lake prevailed even if the conditions were not as cold as during the Oldest Dryas. During the Preboreal (11.7–10 ka cal. BP) Isoëtes echinospora and I. lacustris developed in the eulittoral zone of the lake, which was surrounded by a swamp forest (with Betula nana and B. pubescens). Pinus sylvestris, Betula pendula, Corylus avellana and trees from the Quercetum mixtum rapidly established in the uplands. Occurrences of Gaeumannomyces and Xylomyces fungi – both phytopathogens on broadleaved trees – and decreasing herb values indirectly hint at a close forest canopy. At the beginning of the Boreal (10 ka cal. BP), aquatic and semi-aquatic taxa developed on open water due to longer ice-free seasons (diatoms, micro-algae, Alisma plantago-aquatica, Potamogeton, Typha). The final terrestrialization towards a mire occurred as a consequence of the Holocene warming and related to water chemistry changes (acidification, eutrophication). • During the last deglaciation, a very shallow lake established as demonstrated by palaeoecological data, such as epiphytic diatoms, living on rocks. • Late-Glacial steppe landscape with severe erosion, open grassland and possible mega-herbivore presence. Arctic-like conditions. • Development of shrubs or trees during the Bølling-Allerød interstadial and reduced ice-free season. • Dry and cold conditions persisted from the Younger Dryas to the Early Preboreal. Oligotrophic flora (Isoetids) established in the eulittoral zone. • During the post-glacial warming, the lake tended to acidify. Peat flora and organic matter accumulated and led to the terrestrialization of the lake. [ABSTRACT FROM AUTHOR]

In this study, we present the full sequence of Eemian succession from the Kozłów palaeolake – one of the key sites for Eemian Interglacial in this part of Poland. In the paper, previous palynological and diatom assessments were supplemented by further pollen, Cladocera and macrofossil analysis. This enabled detailed reconstruction of a palaeolake functioning under changes of climate and other environmental conditions during MIS 5e. All identified alterations of trophy, depth and aquatic vegetation within the reservoir point to dynamic changes in early stages of lake functioning, relatively stable conditions in mid-Eemian and gradual lake shallowing starting from Caprinus phase. Thus, Kozlów palaeolake joins the noble group of sites with exceptionally well-recognized multi-proxy records of the Eemian Interglacial environment, and has the potential to become a benchmark for this part of Europe. [ABSTRACT FROM AUTHOR]

The study of faunal communities of the past, and how they have changed to become what they are now, is fundamental to the understanding of the changes in ecosystems that we are witnessing and that are coming in the future. In this paper, we present the small mammal assemblage from Grotta del Sambuco (Massa Marittima, Grosseto), belonging to two archaeologic stratigraphic Units, 5 and 6, both dated to Marine Isotope Stage 2. The assemblage from Unit 6 can be defined as "non-analogue", due to the occurrence of the Narrow-headed Vole Lasiopodomys anglicus and the Southern Birch Mouse Sicista subtilis. Non-analogue communities (i.e., with no equivalent in present time) are frequent during Late Pleistocene in the Italian Peninsula. Starting with Grotta del Sambuco, we describe some of the different factors leading to the origins and disappearance of past non-analogue small mammal assemblages in Italy. Climatic changes and the consequent shifts in geographic distributions of the species play a major role in shaping these communities, eventually leading to extirpation and extinction of cold- or continental-adapted species. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the results obtained by collaborative use of integrative multidisciplinary investigation of a highly unique geological section discovered in the south-eastern part of the Gulf of Finland. The main aim of this study is to identify the Late Pleistocene palaeoenvironmental and palaeoclimatic changes in the study area during one of the most controversial periods in the Late Pleistocene history, which is the MIS 5. Our approach to achieving the goal is based on the investigation of feldspar-based infrared optically stimulated luminescence (IR-OSL) dated records of pollen-induced palaeoclimate and palaeoenvironmental proxies. Palynological analysis and IR-OSL dates of 29 samples for the first time produced a detailed, characterised and dated sequence of palynological zones M6 to M8 ranging from ca. 94 ka to ca. 70 ka and made it possible to determine the chronological sequence of climate changes in this interval. Representative pollen spectra from 69 samples provided convincing evidence of a warm interval of interglacial rank at least during the latter half of MIS 5. The data obtained in the present study from well-preserved deposits of the second half of MIS 5 provided a novel insight into the palaenvironmental conditions during this period. These results seem to contradict the widely held view according to which the last interglacial stage with the climate conditions similar or warmer than today corresponds to only a small part of marine isotope stage (MIS) 5 of the deep-sea stratigraphy, i.e. MISs 5e lasting ca. 11 ka, and the period from 100 ka to 80 ka is attributed to an Early Weichselian glaciation, which in Northern Eurasia reached its maximum at about 90 ka. However, the findings obtained during the present study are also convincingly confirmed by those of our previous long-term investigations of warm climate-related shell-bearing deposits of various origins from Northern Eurasia including climatically highly sensitive Eurasian Arctic palaeo-shelf area. These results indicated that the overwhelming majority of the warm climate-related dates (ca. 82%) is also concentrated in the latter half of MIS 5 in the time range between 110 ka and 70 ka. [ABSTRACT FROM AUTHOR]

The magnetic susceptibility of the loess-paleosol sequence is considered a significant indicator for recording paleoclimate, and the relationship is different between magnetic susceptibility and climate variation in diverse regions. A deep analysis of the composition, content, and evolution mechanism of magnetic minerals is helpful to enhance our understanding of magnetic signals in different regions. This paper presents a systematic study of environmental magnetism and geochemical elements in the loess-paleosol sequence of the Attock (ATT) area in the Peshawar Basin, northern Pakistan, exploring the significance and limitation of magnetic susceptibility as a proxy index of paleoclimate and the variation mechanism of magnetic susceptibility. The results showed that: 1) the ATT section had a magnetic mineral composition similar to that of the Chinese Loess Plateau; however, the contents of different minerals were distinguishable. The loess layer contained a specific amount of magnetite and maghemite and a handful of goethite and hematite. Additionally, the content of soft magnetic minerals was relatively higher than that of paleosol; the paleosol contained maghemite and nearly no magnetite. Furthermore, it contained more hematite and goethite, and the hard magnetic and paramagnetic minerals were dominant; 2) the effective humidity of the pedogenic environment in the ATT section fluctuated around the magnetic susceptibility wetting critical value F (B–C region), resulting in a poor relationship between magnetic susceptibility and climate; 3) Rb/Sr, K/Na, the coefficient of eluviation, and the content of <2 μm particles were well correlated with the stratum and can be used as paleoclimatic variation indicators in this area. Understanding the B–C region is helpful to comprehend the complex relationship between magnetic signals and climate in some areas and better interpret the environmental information carried by magnetic signals. [ABSTRACT FROM AUTHOR]