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The Ner River valley (central Poland) underwent substantial transformation during the Weichselian–Holocene transition as a result of fluvial processes and climate changes, resulting in the establishment of its present shape in the Holocene. A multiproxy study based on organic deposits from a palaeochannel fill (Lutomiersk–Koziówki) shows that after the channel was cut off during the late glacial termination, it became a shallow oxbow, fed by local springs. In the Boreal period, the oxbow lake was also fed by precipitation and became a telmatic environment overgrown by rush and swamp vegetation. Finally, it was covered by overbank deposits. The first flooding phase (9900–9600 cal. BP) was followed by the accumulation of overbank sediments (after 9500 cal. BP) and flooding increased after ca. 9300–9000 cal. BP. Pollen data provide information on the regional vegetation context for local and regional changes. In the Atlantic period, an increase in both summer and winter temperatures is inferred from the pollen data, corresponding to an expansion of thermophilous deciduous forests. While in general, flooding phases of the Early Holocene are poorly recognised in Eastern Europe, the Lutomiersk–Koziówki site may be considered as one of the reference points for this phenomenon in the region. [ABSTRACT FROM AUTHOR]

Foraminifera assemblages are powerful bioindicators of environmental change and were analyzed in a sediment core collected from the Marquesas Keys, located in the southwestern region of the Florida Keys. The composition and abundance of foraminifera tests within the top 85 cm of the sediment core, dated with 14C and 210Pb, revealed changes in foraminifera assemblages in 1990 CE, 1939 CE, and 1872 CE. Based on the ecological preferences of the dominant species, changes in salinity and submerged aquatic vegetation (SAV) cover may have influenced foraminifera species composition. These changes were likely caused by variation in precipitation patterns in the eastern Gulf of Mexico region associated with shifts in the major ocean-atmosphere teleconnections such as the El Niño Southern Oscillation (ENSO), Atlantic Multidecadal Oscillation (AMO), North Atlantic Oscillation (NAO) along with tropical storms and hurricanes. Prolonged periods of the negative phases of these climate phenomena coincided with shifts in foraminifera assemblages. Despite a generally negative impact of the ocean-atmosphere teleconnections on the South Florida region, a well-developed epiphytic assemblage was recorded in the studied core. The assemblage was recorded in the uppermost part of the core and dated to the period between 1990 and 2010 CE. This implies that a dense SAV community was present within the Marquesas Keys Mooney Harbor since at least the early 1990. • Last 150 years climate change record reconstructed for the Florida Keys. • Changes in foraminifera assemblages of the Marquesas Keys sediment core. • Impact of natural phenomena: ENSO, AMO, NAO and hurricanes and droughts. [ABSTRACT FROM AUTHOR]