The spatial distribution of organic and mineral deposits in wider sections of river valleys can be explained by the avulsion of the riverbed downstream of the pond and by the distribution of ponds in the Gołyjonka valley. The results indicate that beavers used to live in the Tuchola Forest in the Middle Ages, as shown by the radiocarbon dates and sequences of mineral-organic deposits found in exposures and geological boreholes. The studies are also backed up with a description of radiocarbon dating of samples.
This paper aims to identify the potential sediments of relict beaver ponds and their sedimentological features. The authors of this paper wish to present the results of field works carried out since 2006 in the Tuchola Forest (Polish Plain). In Poland, beavers are partially protected and their population has spread in virtually every part of the country (except in the highest mountain ranges). The area inhabited by these animals has experienced continuing transformations of terrain relief, geological structure, hydrol-ogy and plant cover. Investigations aimed at disentangling the relative contribution of global versus regional boundary conditions to Neogene Arctic climate warming are needed to understand the extent to which these reconstructions may foreshadow conditions in the future.īeavers have lived in the territory of Poland since the beginning of the Holocene, as testified by bone remains found in archaeological sites of different ages. However, transformation of the once‐contiguous Arctic landmass into a dissected archipelago has undoubtedly changed the nature and future warming potential of the Canadian Arctic region. Some of this warming was likely driven by global atmospheric change and feedbacks that are possible in the modern‐day Arctic. These ΔT estimates, along with independent proxy and vegetation data, depict a dramatically warmer version of the Arctic. These are conservative estimates as they do not account for the more negative δ²Hseawater values during the Neogene. The ΔT estimates ranged from +9.7 to +16.7☌ depending on site and epoch and are corroborated by a suite of independent proxy data for most sites, and for one site (Prince Patrick Island) this study provides the first quantitative ΔT estimates. In this study, hydrogen isotopes of lignin‐methoxy groups (δ²HLM) from Miocene and Pliocene sub‐fossil wood samples (N = 43) at six high‐latitude sites (73–80°N) in the Canadian Arctic Archipelago were used to estimate mean δ²H values of precipitation and temperature anomalies (ΔT) relative to present. Such insights are especially critical in the Arctic where the fastest rates of warming are underway and likely to continue. Proxy‐based reconstructions of Neogene warm climates are a valuable data source for helping to understand what a future, warmer world may look like.
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