Nina Helt Nielsen

Bog bodies are among the best-known archaeological finds worldwide. Much of the work on these often extremely well-preserved human remains has focused on forensics, whereas the environmental setting of
the finds has been largely overlooked. This applies to both the ‘physical’ and ‘cultural’ landscape and constitutes a significant problem since the vast spatial and temporal scales over which the practice appeared demonstrate that contextual assessments are of the utmost importance for our explanatory frameworks. In this article we develop best practice guidelines for the contextual analysis of bog bodies,
after assessing the current state of research and presenting the results of three recent case studies including the well-known finds of Lindow Man in the United Kingdom, Bjældskovdal (Tollund Man and
Elling Woman) in Denmark, and Yde Girl in the Netherlands. Three spatial and chronological scales are distinguished and linked to specific research questions and methods. This provides a basis for further
discussion and a starting point for developing approaches to bog body finds and future discoveries, while facilitating and optimizing the re-analysis of previous studies, making it possible to compare deposition
sites across time and space.

Manuring has often been associated with the emergence of permanent field systems, but manuring practices and intensities are rarely investigated in detail. Previous analyses of phosphorus from Danish Celtic fields show that manuring was carried out at most sites, but due to methodological issues and representativity biases, these results have been difficult to compare and interpret. In this study, samples from three well-preserved field systems in eastern Jutland, Denmark, were analysed with the purpose of investigating the manuring regime. We focused on identifying possible variations between and, in particular, within the individual sites. The main method used was multi-element analysis by Inductively Coupled Plasma Mass Spectrometry (ICP-MS), which was supplemented by soil thin section analysis and analysis of pollen and non-pollen palynomorphs (NPPs). Evidence of animal manure and household waste was found at all three sites and, additionally, material from wetlands was identified at one site. Clear variations between individual fields were identified, which stress the importance of taking composite samples from a large number of fields in order to obtain a more complex understanding of the manuring practices within field systems. Manuring intensity was generally low, indicating a rather extensive use of the field systems in Southern Scandinavia in the Early Iron Age.

Celtic fields are the most widespread type of prehistoric field systems in northwestern Europe. Many questions remain regarding their formation and use, but these may potentially be answered through geoarchaeological investigations. The aim of this study is to contribute to the understanding of the formation of the field systems, the formation of the banks and lynchets demarcating the fields, and the prehistoric land use through geoarchaeological investigations of Øster Lem Hede, one of the best preserved Celtic fields in Denmark. Four trenches dug through selected field boundaries were sampled for geochemical, particle size, thin section, and pollen analyses, as well as radiocarbon and optically stimulated luminescence (OSL) dating. OSL dates show that the investigated banks were formed in the late Bronze Age/early Iron Age (oldest dates: c. 600 ± 140 B.C.), but cultivation predating the field system is also indicated. Particle size and multielement analyses indicate that the banks formed through accumulation of soil from the fields. Dynamic alterations of the layout and field boundaries in the form of added banks and temporarily discontinued boundaries were identified. Geochemistry, pollen, and microscopic inclusions in the soil indicate that the fields were amended with household waste, animal manure, and material from wetlands and heathland. Several different crops were grown including barley, flax, and spurry but also rye appears to have been present in the 2.500-year-old fields.

Elevated soil phosphorus levels are often used as indicators for prehistoric manuring. However, in this article it is argued that though P is indeed a good anthropogenic marker, multi-element analyses can provide more insight into former fertilisation practices and land use.

Here, we compare the ability of both traditional total P analysis and multi-element analysis by ICP-MS to identify prehistoric manuring on soil samples from a well-preserved prehistoric Celtic field system in Denmark. The ICP-MS data set of 58 soil samples was furthermore analysed by multivariate analysis (PCA). Results show that the stronger extraction for the multi-element analysis releases significantly more P than the traditional analysis but similar archaeological interpretations based on relative P enrichments can be made. Among the 42 analysed elements, 11 were significantly (P < 0.01) enhanced in the fields relative to a reference soil, namely Na, P, K, Ca, Mn and Sr and the rare earth elements (REE's), Nd, Sm, Eu, Gd and Dy. Cobalt was the only element which was depleted within the field system. Enhanced P levels show that manuring was practiced, while elevated concentrations of Sr indicate that not only animal manure but also bones/domestic waste was added. Furthermore, the enhancement pattern of some major and minor elements indicate that unweathered subsoil was incorporated into the topsoil – probably through tillage erosion until approximately 2000 years ago. The study also indicates that the banks demarcating the individual fields were made of the same material as the field plough-layers, which makes within-field soil relocation the most likely cause of the banks.