Over the last 60 years, luminescence dating has developed into a robust chronometer for applications in earth sciences and archaeology. The technique is particularly useful for dating materials ranging in age from a few decades to around ,—, years. In this chapter, following a brief outline of the historical development of the dating method, basic principles behind the technique are discussed. This is followed by a look at measurement equipment that is employed in determining age and its operation. Luminescence properties of minerals used in dating are then examined after which procedures used in age calculation are looked at.
The geomorphological impact of small fossorial mammals adapted to digging and living undergroundsuch as rodents can be significant, and both their direct and indirect effects may contribute to landscape formation. This thesis is based on empirical field studies of two burrowing rodent species in sub-polar environments, namely invasive House mice Mus musculus on sub-Antarctic Marion Island and Norwegian lemmings Lemmus lemmus in sub-Arctic Abisko. The spatial distribution, sediment displacements, impact on vegetation and microclimatic effects of the rodents are documented. Invasive mice and rats, introduced on sub-Antarctic Islands during the 19th century, lack natural enemies and are shown to have a significant direct and indirect geomorphic impact by direct sediment displacement, vegetation removal by burrowing, grazing and trampling and thereby exposing the sediments for rain, wind and frost processes. The geomorphic impacts of lemmings are comparatively more limited as they rely on natural hollows and snow cover for protection and do not burrow to the same extent as other fossorial rodents in cold regions.
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