The Flandrian vegetational history of the Loch Lomond area

Stewart, Duncan A. (1979) The Flandrian vegetational history of the Loch Lomond area. PhD thesis, University of Glasgow.

Abstract

Pollen diagrams prepared from the sediments of Loch Lomond and the Dubh Lochan have provided a general overview of the vegetational changes which have occurred in the Loch Lomond area during the Flandrian period. Progressive deforestation since 5000 B.P. and particularly during the last few centuries has been high-lighted with the period of maximum extent of mixed Quercus woodland in the Loch Lomond area having occurred between c.6000 B.P. to c.5000 B.P. The Alnus rise horizon has been demonstrated to have occurred later than expected in the Loch Lomond area. Absolute pollen analysis has enhanced the interpretation of the relative percentage data and has shown that the pollen concentration has varied widely in the Loch Lomond sediment during the Flandrian. Pollen deposition data has been calculated from the Dubh Lochan sediments allowing a comparison to be made with deposition data from other lakes in north west England and Scotland, It has been concluded that concentration of pollen within the Dubh Lochan has occurred. Dinoflagellate analysis has provided the first positive evidence of a marine phase in Loch Lomond's mid Flandrian history. A period of meromixis of ectogenic origin has been hypothesised to account for a laminated band following the marine sediment within which pollen and macrofossil preservation was found to be uniquely good, with pollen counting of the Loch Lomond sediment having been generally taxing. Derived Carboniferous spores were noted throughout the length of the Loch Lomond profile. Analysis of selected terrestrial sites to compliment the picture of the status of Pinus sylvestris gained from the Loch Lomond sediments has been undertaken. The locality of the post Ulmus decline Pinus curve increase demonstrated by the Loch Lomond pollen data has been traced to Glen Falloch. The Glen Falloch peat has recorded a change from Betula woodland to Pinus-Betula woodland at a time generally recognised to be one during which Pinus was in decline in Scotland and Northern Ireland. Fire attributable to man has been considered to account for the initiation of growth of Pinus on the Glen Falloch peat surface. Radiocarbon dating of Pinus wood has demonstrated the continuous presence of Pinus in Glen Falloch until C.1600 B.P., with the present day Pinus trees having been considered to be of natural origin. Data from the Ptarmigan has suggested that in at least one part of the southern Loch Lomond area more Pinus exist today than at any time during the last six thousand years.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Subjects: Q Science > QK Botany
• Colleges/Schools: College of Medical Veterinary and Life Sciences
• Supervisor's Name: Dickson, Prof. James H.
• Date of Award: 1979
• Depositing User: Mrs Marie Cairney
• Unique ID: glathesis:1979-41037
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 21 Feb 2019 15:48
• Last Modified: 21 Feb 2019 16:14
• URI: https://theses.gla.ac.uk/id/eprint/41037