Archaeobotany

Archaeobotany is a field of botany closely tied to archaeology and its techniques. Generally speaking it focuses on the investigation of vegetation history. By analysing plant remains from both historical and prehistorical sites ancient floras are reconstructed. From these, conclusions about the vegetation types and (paleo-)ecosystems can be drawn, part of which those plants once have been. Hence, a battery of questions are dealt with, like:

• Where did our cultivated plants originate and how did they develop?
• Which materials were used for which purposes and why?
• How and when did vegetation alter into its present state?
• Which part did climate changes and man's influence play in these processes?

Closely related to archaeobotany or rather one of its sub-disciplines is palaeoethnobotany which even more deals with the interactions between man and plants during the past.

Plant remains as different as wood fragments, seeds or pollen are used as sources of information. According to this fact, archaeobotany makes use of manifold methods: dendrochronology (with annual ring analysis) and dendroclimatology, palynology (pollen analysis), phytolith and macrofossil analysis, wood anatomy and anthracology (charcoal analysis).

Especially macrofossil analysis has been a main focus of my present work: in contrast to palynology only macroremains, plant remains larger than 100 µm (0,1 mm) are inspected. All plant organs and their fragments yield important information for the scientist, such as diaspores (dispersal units, like seeds, fruits, etc.), leaves, stems or roots.

Wood anatomy and anthracology

• Different from everyday speech, the term wood has a much narrower definition in botany. It denominates the secondary xylem, the layers of tissues that differentiate on the inside of the cambium (the "growth layer" within a plant's stem) during secondary growth and mainly serve water transport and stabilisation. The cells differentiating on the cambium's outside become inner bark (secondary phloem). The tissues forming the wood are highly differenciated, permitting researchers to classify the respective plants by examining even the smallest pieces. Normally, an identification accurate to the genus can be achieved, often to the species (see wood identification).Their high specificity makes wood remains a very important category of botanical finds. Thus, archeobotany makes use of wood anatomy as a valuable auxiliary discipline for vegetation reconstruction.

This is also valid for charcoal, albeit examination methods differ slightly from those applied to uncharred wood. Considered the fact that charred wood hardly is subject to any decomposition (except for mechanical force), it can persist over long periods of time. Charcoal finds document variations in both vegetation and climate and serve as important resources for palaeoclimatology.

Apart from the archaeological context, wood anatomy also applies, for instance, to dendroecology and materials science.