1. Note five important methods of Quaternary palaeoecology.
   Important methods of Quaternary palaeoecology: Radiocarbon dating, pollen analysis, dendrochronology, geochemistry, stable isotope analysis.
    
2. How does pollen analysis work?
   Pollen analysis is based on the identification and counting of the various pollen and spores types which have been preserved in inorganic and organic material, mainly peat.
    
3. Which methods are used to reconstruct Holocene glacier fluctuations?
   see Figure 2 in Results - "Holocene"
    
4. How can we date fossil soils and fossil wood?
   Radiocarbon and dendrochronology
    
5. a) In an isotopic record of an ice core, values are less depleted in ¹⁸O during the last 10'000 years (Holocene) than before (Late Glacial Time and Last Glacial Maximum). This indicates that the Holocene is a warmer period.
   b) Explain why this is the case.
   see explanation under Stable isotopes.
    
6. Imagine you are investigating a lake core and want to date it with the radiocarbon method. What compontents do you look for and why is this material suitable?
   Any material which is composed of carbon may be dated: pollen, plant macrorests, wood, etc.
   Organic material is suitable for the following reason: While an organism is alive, the decaying radiocarbon is continually replaced and the ratio of the instable ¹⁴C to the stable ¹²C remains constant and is the same as the ratio in the atmosphere. When an organism dies, the carbon intake ceases. From this point of time the amount of ¹⁴C decreases through time by its radiometric decay of 5370+/-40 years.
    

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29 August 2011
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