UNDERSTANDING SOILS IN URBAN ENVIRONMENTS.

193 Pages·2021·8.054 MB·English

by  DR PAM. MURPHY BRIAN W. HAZELTON

2ND
EDITION
Understanding Soils
in Urban
Environments
Pam Hazelton and Brian Murphy
2ND
EDITION
Understanding Soils
in Urban
Environments
Pam Hazelton and Brian Murphy
© Pam Hazelton and Brian Murphy 2021
All rights reserved. Except as permitted by applicable copyright laws, no part of this publication may be
reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical,
photocopying, recording, duplicating or otherwise, without the prior permission of the copyright owner.
Contact CSIRO Publishing for all permission requests.
The authors assert their moral rights, including the right to be identified as an author.
A catalogue record for this book is available from the National Library of Australia.
ISBN: 9781486314010 (pbk)
ISBN: 9781486314027 (epdf)
ISBN: 9781486314034 (epub)
Published in print in Australia and New Zealand, and in all other formats throughout the world, by CSIRO
Publishing.
CSIRO Publishing
Locked Bag 10
Clayton South VIC 3169
Australia
Telephone: [phone]
Email: [email protected]
Website: www.publish.csiro.au
A catalogue record for this book is available from the British Library, London, UK.
Published in print only, throughout the world (except in Australia and New Zealand), by CABI.
ISBN 9781789249934
CABI CABI
Nosworthy Way We Work
Wallingford One Lincoln Street, 24th Floor
Oxfordshire OX10 8DE Boston, MA 02111
UK USA
Tel: [phone] Tel: [phone]
Fax: [phone] E-mail: [email protected]
Email: [email protected]
Website: www.cabi.org
Front cover (clockwise from top): View of some rooftop gardens in Canberra, Australia; surface soils over a
sodic subsoil (Yellow Sodosol) in central west New South Wales, Australia; aerial view of the outskirts of
Marrakesh, Morocco, showing new housing developments (photos by Brian Murphy).
Set in 11/13.5 Minion & Helvetica Neue
Edited by Joy Window (Living Language)
Cover design by Cath Pirret
Typeset by Envisage Information Technology
Printed in China by Leo Paper Products Ltd
CSIRO Publishing publishes and distributes scientific, technical and health science books, magazines and
journals from Australia to a worldwide audience and conducts these activities autonomously from the research
activities of the Commonwealth Scientific and Industrial Research Organisation (CSIRO). The views expressed
in this publication are those of the author(s) and do not necessarily represent those of, and should not be
attributed to, the publisher or CSIRO. The copyright owner shall not be liable for technical or other errors or
omissions contained herein. The reader/user accepts all risks and responsibility for losses, damages, costs and
other consequences resulting directly or indirectly from using this information.
Acknowledgement
CSIRO acknowledges the Traditional Owners of the lands that we live and work on across Australia and pays its
respect to Elders past and present. CSIRO recognises that Aboriginal and Torres Strait Islander peoples have
made and will continue to make extraordinary contributions to all aspects of Australian life including culture,
economy and science. CSIRO is committed to reconciliation and demonstrating respect for Indigenous
knowledge and science. The use of Western science in this publication should not be interpreted as diminishing
the knowledge of plants, animals and environment from Indigenous ecological knowledge systems.
The paper this book is printed on is in accordance with the standards of the Forest Stewardship Council® and
other controlled material. The FSC® promotes environmentally responsible, socially beneficial and
economically viable management of the world’s forests.
Jul21_01
Contents
Preface for second edition iv
Acknowledgments v
Chapter 1 Soils in an urban environment 1
Chapter 2 Soil characteristics important for urban soil management 17
Chapter 3 Soils and the hydrological cycle in urban environments 51
Chapter 4 Soil property problems for engineering works 73
Chapter 5 Soil contamination in urban areas 95
Chapter 6 Urban soils and ecosystems 121
Chapter 7 Soils and vegetation: contributing to a more sustainable
urban environment 135
Chapter 8 Urban development on coastal soils 153
Chapter 9 Interpretation of soil attributes in an urban environment 165
Glossary 171
Further reading 179
Appendix: Some international soil classifications 180
Index 183
iii
Preface for second edition
Soil assessment and management in urban areas has received increasing attention
as a consequence of the increasing urbanisation of the world’s population. In 1950
on a global basis, only 30% of the world’s population lived in urban areas. By 2016
urban population had increased to 54% with a projection of 66% in urban areas in
2050, with some nations having 80 to 90% of the population living in urban areas.
Soil underlies most of our cities and urban hinterlands. Hence this shift in
population density and change in land use increases the necessity to understand
and manage the functions of soil properties to adequately sustain the day- to- day
activities and requirements of urban life. This book introduces the reader to an
understanding of soils in an urban environment. It explains what soils are, and
describes the nature of soils and the importance of the different soil properties in
an urban environment and how these can influence and be influenced by human
activities. The book acknowledges that, in an urban environment, there is a large
capacity for human activity to change the natural soil through engineering and
infrastructure development. It acknowledges the link between soils and ecological
sustainability in the urban environment, and discusses the effect of climate change
on soils in a variety of situations.
The reading list at the end of each chapter provides an indication where more
detailed and technical information can be found on the various aspects of soil
properties, soil management and the hazards and limitations associated with soils
in an urban environment.
iv
Acknowledgments
The authors wish to thank Jillian Murphy for the design and production of figures
in this book. We thank Dr Tatiana Prokofieva for supplying the publication on the
soils of Moscow that she and her colleagues produced. We also thank her for her
useful comments about the section on the urban environment of Moscow.
v
This page intentionally left blank
1
Soils in an urban environment
Introduction
Soil assessment and management have generally focused on agriculture,
horticulture and forestry, but more recently have given increased attention to
urban soils, no doubt as a consequence of the increasing urbanisation of the
world’s population. In 1950 globally only 30% of the world’s population lived in
urban areas. By 2016 urban population had increased to 54% with a projection of
66% in urban areas in 2050, with some nations having 80 to 90% of the
population living in urban areas (Burghardt et al. 2015; Lal and Stewart 2018).
Soil underlies most of our cities and urban hinterlands. Hence this shift in
population density and change in land use increases the necessity to understand
and manage the functions of soil properties to adequately sustain day- to- day
urban activities as the land surface is sealed by buildings, concrete, carparks or
low- density urbanisation (Prokop et al. 2011; Gardi et al. 2015; Hendawy et al.
2019; Wadduwage et al. 2017).
In the urban environment soils can be in their natural condition or be slightly
disturbed, completely disturbed or, in some cases, manufactured, as in human-
made landscapes (Leake and Haege 2014; Wessolek and Toland 2017). Soils and
these properties can be modified when the land use is changed, whether from a
more or less natural state in a rural environment to an urban condition. Disturbed
soils especially differ from soils formed in situ because their natural profile layers
2 Understanding Soils in Urban Environments
have been mixed, destroyed or removed. Under human influence, natural soils may
be buried under fill, or chemical and waste materials may have been added. These
activities can result in large changes in the physical, chemical and engineering
properties of the natural soils at a site. Subsoils can be exposed or mixed with
topsoils and compaction also may have occurred. Sealing the soil surface can lead
to changes in the soil function (EC 2012).
The natural properties of the soils, or the changes to their properties, can
determine whether the soils are able to carry out the physical, chemical and
biological, hydrological, environmental and engineering functions required for the
urban environment. Failure of the soil to function as expected can have significant
environmental and economic consequences on the urban landscape, resulting in
serious impacts, including damage to buildings and roads, land slip, poor water
quality, soil contamination, dryland salinity and degraded ecosystems (Scheyer
and Hipple 2005; Hicks and Hird 2007).
This book is an introduction to understanding the importance of fundamental
soil properties, their functions and their behaviour in a variety of urban
environments.
Nature of soils
Soil sometimes occurs as weathered in situ material derived from bedrock. In
other situations, it comprises materials that have been transported to or from sites
by various agents, including water, wind, gravity, ice and – as frequently occurs in
urban areas – human activity.
The soil and its properties result from the interaction of chemical, physical and
biological activities. Soil is a unique resource and a distinctive identifiable part of
the environment. The soil type is influenced by environmental factors, including
the parent material from which it is derived, vegetation, climate, topography and
availability of water. Soil is, in effect, the ultimate interface between the geosphere,
the atmosphere, the hydrosphere and the biosphere (Rimmer 1998; Scheyer and
Hipple 2005; Lal and Stewart 2018). The effects of human impact on soils are
linked to the way in which the soil is used and the land managed (Scheyer and
Hipple 2005).
1 – Soils in an urban environment 3
Soils in the urban environment
Soil lies beneath the feet of urban dwellers – it nourishes gardens and parklands,
supports building foundations, underlies transport corridors and is often used as a
sink for effluent and waste disposal (see Figures 1.1 and 1.2 and Table 1.1). It is the
medium in which vegetation grows, often to remediate sites which have been
scarred by change in the landscape (Hazelton 2006). A variety of professions
require urban soils data: urban and land use planners; engineers; builders and
architects; urban farmers and park, forest and habitat managers; and stormwater
and water quality managers (USDA 2019).
Urban soil is an important ecological asset (Sauerwein 2011) and a key
component of the urban ecosystem and the natural infrastructure of urban land
(Scheyer and Hipple 2005; Hecht and Sanders 2007). Soils affect urban ecosystem
functions by:
• absorption of rainfall to prevent flooding and runoff – the urbanisation of
rural land can significantly increase runoff because of larger paved, sealed and
roofed areas;
• absorption and filtering of effluent and pollutants such as oil- based pesticides,
herbicides and heavy metals, thereby preventing them from entering water
supplies – the concentration of human activity increases the local output of
effluent and pollutants, which increases the potential for contamination;
• nourishment of gardens, parklands and sporting grounds – in urban areas
there is an increased need for revegetation growth for recreation and environ-
mental rehabilitation; soils store and supply both water and nutrients for use by
plants;
• natural habitat protection of conservation areas, especially endangered
ecological communities
• the use of soils as foundation materials for buildings and transport corridors.
The impact of urbanisation on the environment is so critical that the extent of
impervious surfaces and urban/suburban developed land are key indicators of the
health of water and terrestrial ecosystems (Hecht and Sanders 2007). Although
knowledge of soil management has always been essential in rural environments, it
is equally important, or even more, with the global growth in urban population to
understand and manage soils in an urban environment for sustainable
environmental management (see Figure 1.3).