Multiproxy evidence of `Little Ice Age' palaeoenvironmental changes in a peat bog from northern Poland

Abstract

`Little Ice Age' (LIA) climatic deteriorations have been abundantly documented in various archives such as ice, lake sediments and peat bog deposits. Palaeoecological analyses of peat samples have identified these climatic deteriorations using a range of techniques, for example palynology, plant macrofossils, testate amoebae or carbon isotopic analyses. The use of inorganic geochemistry and the reconstruction of dust fluxes has remained a challenge in tracing the nature of LIA climatic changes. Although the idea of enhanced erosion conditions and storminess is commonly discussed, the conditions for dust deposition in peatlands over Europe during the LIA are rarely favourable, because the natural forest cover over Europe was much more important than nowadays, preventing dust deposition. This intense forest canopy masks the deposition of dust in peatlands. In northern Poland, near the Baltic shore, the Słowińskie Błota area was deforested around AD 1100, ie, just before the LIA, and therefore constitutes a key area for the reconstruction of LIA climatic change. With the support of a well-constrained chronology, climatic fluctuations are recorded in an ombrotrophic bog using inorganic geochemistry, plant macrofossils and carbon isotopic analyses. The reconstruction of LIA climatic changes is in good agreement with other records from Poland and NE Europe. However, a c. 50-year discrepancy can be observed between various records. This discrepancy is possibly due to progressive time-dependent cooling gradient from north to south Europe.