|Title: ||Pedogenesis on the Sefton Coastal Dunes, NW England|
|Advisors: ||Booth, Colin A.|
Fullen, Michael A.
Trueman, Ian C.
|Publisher: ||University of Wolverhampton|
|Issue Date: ||2010 |
|Abstract: ||This work examines the use of pedo-properties to identify dune soil system responses to
environmental change on the Sefton coast, based on the development of conceptual pedogenic
models. Previous environmental change and shoreline dynamics are determined through O.S.
maps and aerial photographs, while present day processes are investigated through a dune-toe
photographic survey and seasonal monitoring by fixed point photography. Topsoil (0-5 cm)
physico-chemical characteristics are presented in a series of baseline GIS maps, displaying
spatial pedo-property variation across the dune landscape. Combined with vegetation data,
topsoil analysis identifies 10 distinct pedo-environments. Physico-chemical characteristics of
associated National Soil Resources Institute (NSRI) soil profile classifications and an exposed
stratigraphic section are presented graphically in a proposed sequence of development.
Topsoil and soil profile samples are analysed for soil pH, soil organic matter (SOM) content,
particle size, geochemical composition and mineral magnetism. Significant differences (p <0.05)
are apparent for the suite of topsoil characteristics collated, indicating discrete dune
environments are influenced by specific soil properties. Distinct down-profile variations in soil
characteristics are also apparent between dune environments, highlighting pedological
dynamism. Multivariate Factor analysis groups bare sand and mobile dune communities into
‘frontal dunes’ and fixed dune community, pasture, scrub, deciduous woodland and coniferous
plantations into ‘hind dunes’, separating these topsoil environments from heath and slack
communities. Factor analysis also identifies linkages between pedo-characteristics within soil
profile horizons, suggesting pedogenesis on the Sefton dunes initiates as raw sand, progressing
to sand-pararendzinas through leaching of nutrients. Desalinization and decalcification
processes lead to brown earth development, followed by increased acidicification, subsequently,
resulting in micro-podzol formation. Groundwater gley soils are associated with dune slacks,
where drainage is inhibited and anaerobic conditions prevail. Analysis of buried soils suggests
such pedo-environment formations are cyclic, responding to phases of shoreline
regression/transgression, dune activity and stabilization.
Conceptual models are designed to graphically demonstrate pedogenesis under both erosion
and deposition regimes on the Sefton coast. Regression equations and correlation coefficients
between pedo-properties and distance from mean high water are used as a proxy for soil age,
which represent lateral soil maturity from the unstable frontal dunes to the stable hind dunes
inland. The models simulate formation and process of the full array of soil properties, accounting
for geomorphological impacts and anthropogenic influences. This has great implications for
dune managers by raising awareness of pedogenesis as an integral part of nature and
associated habitats, which could be incorporated in future shoreline management plans (SMPs).|
|Type: ||Thesis or dissertation|
|Description: ||A thesis submitted in partial fulfilment of the requirements of the University of Wolverhampton for the degree of Doctor of Philosophy|
|Appears in Collections: ||E-Theses|
|Files in This Item:|
|Millington_PhD thesis.pdf||26514Kb||Adobe PDF|
All Items in WIRE are protected by copyright, with all rights reserved, unless otherwise indicated.