The Prehistoric Wetland Site of Náklo (Moravia, Czech Republic) – a Unique Piece of History

This paper summarises the results of an investigation from the former oxbow lake near the village Náklo. The study profile (“Náklo – Under the church”) is situated near an archaeological site which is important due to the presence of pile constructions and a deposit of bronze vessels from the Halstatt Period. The study focused on the plant macroremains and xylotomy analysis. Only a few plant macroremains studies from lowland wetland sites are notable for the documented presence of archeophytes in central Europe. Our study confirmed long-term human impact and the important influence of human activities on the alluvial floodplain vegetation, especially during the Late Bronze Age and Hallstat Period. Our analysis of wood enabled the presence of alluvial forest with dominance of Salix, Populus, Alnus, and Ulmus to be reconstructed. IANSA 2017 ● VIII/1 ● 9–16 Alexandra Bernardová, Jan Novák, Vendula Vránová: The Prehistoric Wetland Site of Náklo (Moravia, Czech Republic) – a Unique Piece of History 10 sediments (Czudek 1972). Fluvisols and chernozem were mapped as the most common soils near Náklo village (AOPK 2005). The lowland area falls into the Thermophyticum phytogeographical region with a slightly dry and continental, central European climate. The mean annual precipitation is 550–600 mm, and mean annual temperature 8.5–9°C (meteorological site: Olomouc; Quitt 1971). At present, the lowland region is predominantly agriculturally managed with forests covering only a small percentage of the landscape. The current riverine forests belong to the Ulmenion alliance (Chytrý 2013), and the occurrence of Salix and Alnus is associated with river banks and wetlands. Oak-hornbeam forests (Carpinion) are typical of the drier part of the lowland, which hydrologically does not belong to the Morava river catchment. As potential natural vegetation, hardwood forests of lowland rivers (Ulmenion) and oak-hornbeam forests (un. Carpinion) have been recreated in the area (Neuhäuselová, 2001). Litovelské Pomoraví is influenced by long-term agricultural management (Čižmářová et al. 1996). A lot of findings, including chronologically almost the whole of prehistory, the Middle Ages, and the Modern Period, have Figure 1. Unique find of a deposit of bronze vessels coming from the sediments, which could be dated to the Hallstatt Period, found at the beginning of the 20th century. Figure 2. Location of the studied area. The circle marks the location of the trench where the sediement was retrieved. Source: https://geoportal.gov.cz. 0 10 km IANSA 2017 ● VIII/1 ● 9–16 Alexandra Bernardová, Jan Novák, Vendula Vránová: The Prehistoric Wetland Site of Náklo (Moravia, Czech Republic) – a Unique Piece of History 11 been obtained up to the present (e.g. Čižmář, Kohoutek 1999; Oliva 2003; Peška 2001; Wankl 1889). Among the periods of greatest population density, we can include, for example, the period of the Linear Pottery Culture (7550–6850 cal BP), Late Eneolithic (4850–4450 cal BP), or the Late Bronze Age (3250–2750 cal BP). 2.2 Methods A 285 cm long sediment profile was recovered from a trench near the place known locally as “Under the church” (N 49°39′20.3′′ E 17°08′03.4′′) using Kubiena tins (50×10×10 cm). Wood trunks, twigs and branches were sampled separately during the recovery of the sediment. Slices were cut from big trunks. The profile was then sedimentologically described, and subsampled at regular intervals of 3 cm. Sediment samples were washed through 0.25 mm sieves. Macroscopic remnants were picked out and identified with the help of a reference collection and determination literature, e.g. Anderberg (1994), Berggren (1981) and Cappers et al. (2006). Pollen analyses from the samples were not carried out, as the sediment was sandy and the pollen concentration of several tested samples was very low and unrepresentative. A study from another Moravian locality Únanovka encountered a similar problem (Petřík et al. 2015). Macrofossil diagrams were created in the Tilia program (Grimm 2011). The nomenclature follows the determination key to the Czech flora (Kubát et al. 2002). Wood fragments were identified with the help of a reference collection and standard identification keys (Greguss 1972; Schweingruber 1990) using a light microscope with 200–500× magnification. The wood fragments were quantified as the number of analysed fragments. Plant macrofossils were used for AMS radiocarbon dating in the Poznań Radiocarbon Laboratory. For the radiocarbon dating of wood fragments, samples were sent to the CRL – Radiocarbon Laboratory of the Nuclear Physics Institute, CAS. The 14C data were calibrated to calendar ages using the OxCal 4.2 online application (Ramsey 2009) based on the IntCal 13 (Reimer et al. 2013) calibration curve.