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Late Quaternary vegetation history of Craven, Yorkshire DalesRushworth, Garry January 2010 (has links)
This thesis investigates new late Quaternary vegetation records from four sites in the Craven District of the Yorkshire Dales. The chosen sites fall along an east-west transect broadly following the line of the south Craven Fault. The rationale for site selection was not based on conventional palynological considerations of potential for rich core samples, rather to provide a range of different locations within a distinct micro-region each existing in some specific proximity to known archaeological features. The logic was to attempt to get beyond broad 'natural' climatological and vegetational inferences to understand the nature and level of potential anthropogenically produced change at a local scale as a sub-set of natural change in a broader regional zone over time. The sites reveal varied vegetation histories from the Late Glacial period to the present day and all show signs of being influenced by changes in their arboreal structure at some time, although no two sites have exactly the same vegetation communities until around 5000 BP when the tree canopy is opened to allow an open grassland to dominate. The results indicate the possibility that Betula values, in particular, might indicate cooling events found in the Greenland ice cores for Greenland Interstadial 1 as well as the Pre-boreal Oscillation and the Holocene 9.3 ka BP Event. Closer chronological control of such values could help to determine whether vegetational dynamics were synchronous with fluctuations in temperature and the speed with which trees respond to severe temperature fluctuations. Various hiatuses identified during analysis of the cores may be caused by human influence on the wetlands, given that archaeological evidence from caves shows human occupation of the Craven area from the late Upper Palaeolithic onwards.
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Late Quaternary vegetation history of Craven, Yorkshire Dales.Rushworth, Garry January 2010 (has links)
This thesis investigates new late Quaternary vegetation records from four sites
in the Craven District of the Yorkshire Dales. The chosen sites fall along an
east-west transect broadly following the line of the south Craven Fault. The
rationale for site selection was not based on conventional palynological
considerations of potential for rich core samples, rather to provide a range of
different locations within a distinct micro-region each existing in some specific
proximity to known archaeological features. The logic was to attempt to get
beyond broad ¿natural¿ climatological and vegetational inferences to understand
the nature and level of potential anthropogenically produced change at a local
scale as a sub-set of natural change in a broader regional zone over time. The
sites reveal varied vegetation histories from the Late Glacial period to the
present day and all show signs of being influenced by changes in their arboreal
structure at some time, although no two sites have exactly the same vegetation
communities until around 5000 BP when the tree canopy is opened to allow an
open grassland to dominate. The results indicate the possibility that Betula
values, in particular, might indicate cooling events found in the Greenland ice
cores for Greenland Interstadial 1 as well as the Pre-boreal Oscillation and the
Holocene 9.3 ka BP Event. Closer chronological control of such values could
help to determine whether vegetational dynamics were synchronous with
fluctuations in temperature and the speed with which trees respond to severe
temperature fluctuations. Various hiatuses identified during analysis of the cores
may be caused by human influence on the wetlands, given that archaeological
evidence from caves shows human occupation of the Craven area from the late
Upper Palaeolithic onwards. / Natural Environment Research Council
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