Ian Bradbury’s The Biosphere introduces us to the first, and perhaps
the most difficult, question, about how the living world functions and interacts
with the non-living world, the biosphere. It’s a tall order to cover this ground
in a couple of hundred pages—taking in not only the chemistry of life, the
operation of genetics, natural selection, evolution, taxonomy and ecosystem
function, but also energy flow, biogeochemical cycling and
biogeography—without missing too many steps or becoming oversimplified.
Bradbury succeeds, however: Steering clear of distracting detail and distressing
equations, he provides a well-written introduction that should inspire the
beginner to look further.

Should the student then move on to Ecological Dynamics by W. S. C.
Gurney and others? Well, only if equations delight rather than distress
you—this is not a text for the mathematically challenged. Indeed, if you
don’t revel in calculus, then it’s hardly worth opening the book. Modelling is
clearly a vital way of moving beyond verbal descriptions of the workings of
nature, possibly the most important, but this particular account will be most
useful at advanced undergraduate or even postgraduate level.

Gerod Guyot’s Physics of the Environment and Climate, on
the other hand, is far more accessible and should be helpful to anyone with
A-level physics. It covers many of the areas that concern the environmental
scientist, including the nature of electromagnetic radiation and its interaction
with plants, heat transfer, convection, evapotranspiration, cloud formation and
atmospheric circulation. A pleasant feature of this book is that the biologist
or geographer can start from a point where they feel secure (at the opening of
stoma, or the formation of an anticyclone, for example) and be carried gently
into the physics of the event, without losing attention or interest. This book
definitely deserves a place on the reference shelf.

These books may help us to understand how all those natural systems work, but
what about those aspects of the planet that are going seriously awry? How can we
keep track of pollution and other changes? Enter Andrew Clarke’s Industrial
Air Pollution Monitoring. The book is concerned with methodology,
explaining the limits put on industrial emissions and the ways in which these
can be checked. How, for instance, do we determine the levels of nitrogen
oxides, organic volatiles, dioxins, or sulphur dioxide in the atmosphere?
And how accurate are these methods? Clarke answers our questions concisely and
clearly.

Then there’s the question of climatic change. We know about the steady but,
on the face of it, rather unimpressive rise in global temperature. Will this
make a difference to our way of life? It might, especially if it increases the
number and severity of droughts, floods, cyclones, hurricanes or even simple old
heat waves.In Climate, Change and Risk, Thomas Downing and
others look at the spectacular events that might accompany a gradually rising
temperature. Severe agricultural drought is a regular event in the Mediterranean
region, for example, and it is predicted to become more frequent and widespread
in central Europe. Winter flooding triggered by increased rainfall is set to
rise in eastern England and, surprisingly, in Finland. The economic impacts of
changes such as these, especially for the insurance industry, make gloomy
reading.

Cynthia Rosenzweig and Daniel Hillel’s Climate Change and the Global
Harvest explores the effects of climate shift on agriculture. It is a mixed
blessing: higher levels of carbon dioxide may raise the productivity of many
crop plants, but higher temperatures will bring more and pests and diseases.
Drought will limit cereal crops such as wheat, especially in Mexico, Egypt and
Pakistan. Evidence and extrapolations from the best models make this a
thought-provoking and sobering book.

All forests, natural or planted, are also vulnerable to climate shift. The
collection of research papers in European Forests and Global Change,
edited by Paul Jarvis, suggests that different tree species will vary markedly
in their response to increased carbon dioxide. As you might imagine, species
will differ in their responses, but there will be great variation even within
each species.

So what can we do? Since carbon emissions are at the root of the climate
problem, we could try alternative energy sources. Biomass energy from
plantations is an approach that is carbon neutral in the long term, but it
requires immense amounts of land. Energy Plant Species by N.
El Bassam is mainly a taxonomic survey of plants potentially suitable for energy
plantations in different climates and habitats, from willows to water hyacinth.
An interesting member of the list is cannabis, with a potential biomass
productivity of 18 tonnes per hectare per year. Some seed-producing varieties of
cannabis also produce 600 litres of oil per hectare.

The danger of making full use of our landscape for energy production is that
it would severely curtail the space for the conservation of biological
resources—which happens to be the title of a book by E. J. Mulner-Gulland
and R. Mace. The emphasis here is clearly on the resources. The book is a
down-to-earth assessment of how to calculate how many animals (or trees) we can
harvest without disrupting or degrading natural populations. There is much to be
said for this approach, because habitats, and therefore species, are much more
likely to survive if they can be made productive in a sustainable way. The
errors of overfishing, taking too much wood and destroying populations of
elephants could all be averted by a rational use of resources: says this useful
book, in which the issues are amply backed by case studies. This is the tough
but real face of conservation, and should be read because it could change
students’ attitudes fundamentally.

There are, of course, ecosystems too degraded to be salvageable by
conventional techniques. Can such places ever be restored to health? That is the
main theme of Krystyna Urbanska’s Restoration Ecology and
Sustainable Development. Putting health back into the soil, establishing
vegetation on degraded and eroded lands, adding arthropods into newly
established vegetation, repairing damaged saltmarshes and other tidal
wetlands—are all dealt with in this repair manual for ecosystems.

So, does the material in these books encourage us to place our faith firmly
in the environmental sciences? Elements of comfort and encouragement are to be
found here, but perhaps we should still spend some time in prayer-just in
case.

IF ANYONE doubts the possibility of sustainable growth, they should look at
the publication of books on ecology and the environment. There seems to be no
end to the stream of texts intended to inform, enervate, shock, exasperate and,
just occasionally, reassure a public increasingly aware of the environment. If
this literary flow is generated by public demand and concern, just what
questions are we asking to produce such a proliferation of books?

Here are a few possible contenders: what use is nature to us? Do we need all
these species of animals and plants, or can we afford to let some die out? Is
extinction inevitable? What do we have to do to conserve and protect species? Is
it as serious as some suggest? What can I do about it?

These questions strike at the heart of the environmental concerns of many,
and scientific authors have in many ways tried to answer them. Take Eugene
Odum’s Ecology: A Bridge Between Science and Society, for example. The
philosophy behind this text is tried and tested. Much of it will look familiar
to those of us who were taught ecology several decades ago. Understand the
functioning of the ecosystem, the relationships between organisms and the
physical world, says Odum, and you are well on the way to appreciating
environmental problems and their solutions. Essentially the ecogospel according
to Odum as proclaimed in the 1960s, he has given it a late-20th century social
face-lift by acknowledging that we humans are part of many, perhaps most,
ecosystems.

Following a similar philosophical vein—that is, information first, but
with a much more up-to-date and applied content—is Michael Allaby’s
Basics of Environmental Science.This is a well-packed compendium of
information, covering issues from the development of bogs to the operation of a
blast furnace, both important in understanding our environment. The text is
densely packed, however, which may prove a deterrent to the more verbally
challenged student (a far from endangered species). Odum’s book is less
threatening in its presentation but Allaby’s is more informative, applies more
to human problems.

A more innovative approach to spreading the environmental gospel is Yvonne
Baskin’s The Work of Nature. Not a graph nor a table to be seen here,
but an occasional line drawing of a mushroom or a moose illustrates a text that
carries you along as strongly as a Stephen King thriller. It is difficult to
believe that this friendly book has emerged from such a prestigious
international group as the Scientific Committee on Problems of the Environment,
which commissioned this accessible book from a skilled science writer. Its
policy ensures that the book marries scientific credibility with literary
quality, rare indeed.

Perhaps the most attractive feature is that The Work of Nature
teaches in the manner of Aesop, providing stories that illustrate important
truths without the clutter of scientific data. Purists may object to this, but
references are supplied for those who doubt. Baskin tackles some of the most
difficult questions from my list: which species really are the most important to
the continued stability of nature and how can we ensure that the biological
resources of the planet are maintained at an adequate level to service the needs
of our species? The answers, reinforced with subtly conveyed information based
on a wealth of scientific data, are absorbed without you even realising that you
are being instructed as well as entertained. This is an ecology text to curl up
with.

The stewardship of plants and animals, wildlife husbandry, has been renamed
“conservation biology”. This is the title of a book edited by Ian Spellerberg
that seeks to lay out the ground rules of the young science. Although
Conservation Biology covers all the important issues that need to be
considered, it seems to be standing on its head, beginning as it does with
legislation, conservation strategy and planning and only eventually working
through to taxonomy, population conservation, ecosystems and protected areas.
But because the chapters are written effectively as conservation modules, you
can pick and mix, making this a valuable teaching source. Some topics are
covered in a new and exciting way, such as the selection and location of
protected areas.

A more advanced treatment of a similar set of subjects is provided by The
Ecological Basis of Conservation by S. T. A. Pickett and colleagues, who also
introduce more of an economic approach with devices such as “cost benefit
contours” that can be overlaid on landscapes.

Pollution seems to be an inevitable result of economic activity. It is not
difficult to be aware of it, but far less easy to understand its chemical and
physical complexity. In the second edition of Roy Harrison’s Pollution, we have
a student-friendly introduction that does not avoid the complexities, but
presents them in a way that can be appreciated even by those with a minimum of
background in the physical sciences. An ideal pollution primer for the
environmental science student.

More advanced, and confining its attention to a single kind of pollution, is
Air Pollution: An Introduction by Jeremy Colls. Like Harrison’s book, it
tends to have a distinctly British flavour in its choice of illustrations, but
Colls reaches further into the biological realm by investigating the
physiological and biogeographical impact of air pollution on animals and
plants.

Since we humans are so deeply involved in global ecology, can we not begin to
play a more positive role? Must we always act the wicked stepmother?
Industrial Ecology and Global Change,a series of articles edited by Robert
Socolow and others, takes a refreshingly positive and constructive look at our
impact on the natural world and the remedial policies we should adopt for the
future. Recycling of what we currently regard as waste pollutants (such as heavy
metals), renewable energy (particularly biomass), improved monitoring of
background levels of toxins, international collaboration and control, are among
the many topics considered. This is an important and well-presented text,
particularly suitable for those already well grounded in environmental
science.

We all have to respond to the changes we see taking place in our world,
whether they are a result of pollution, habitat destruction or climate shifts,
but predicting the responses of the natural world stretches the science of
biology way off the scale. Fakhri Bazzaz, in Plants in Changing
Environments, has assembled an account of how we can project our knowledge
of physiology, population ecology and community interactions into the future.
Despite all the unknowns in the equation, it is possible to make cautious
predictions. The more disturbed environments of the future, for example, will be
more appropriate for species normally associated with the early stages of
succession; and a fragmented landscape will favour species with good dispersal
capacities.

Fragmentation is such a marked feature of modern landscapes that population
ecologists have found a need for a new concept, that of “metapopulations”,
populations of an organism that are split into spatially separated components.
The concept is particularly important for the conservationist, and Dale
McCullough has brought together in Metapopulations and Wildlife
Conservation a collection of papers that examines the theory, genetics, and
conservation applications of the subject, richly illustrated by mostly North
American case histories from spotted owls to sea lions.

Environmental publishing has moved on from the shock of Rachel Carson’s
Silent Spring. We needed a period of gloom to drive away complacency, but
the mood is now more optimistic and activist. Ecology books are changing with
the times. Their message now is that life will go on whatever, but perhaps not
life as we know it.

The Idea of Biodiversity by David Takacs, Johns Hopkins
University Press, ÂŁ25, ISBN 0 8018 5400 8

VARIETY, they say, is the spice of life, and has recently become the
watchword of the conservation movement. The word “biodiversity” is now almost
compulsory in the title of grant applications and papers submitted to
conservation journals. But what does it mean? And should it be the primarily aim
of all our management efforts in the landscape?

It is said that we only start to appreciate the value of something when it
disappears, and maybe this explains today’s fad for biodiversity.

Each of us views nature with different eyes, so it is natural that we have
our own reasons for the value we place on its amazing variety. Our response may
be based on science, but it also contains subjective elements that are
essentially personal. Yes, even scientists have personal feelings, which becomes
clear as you read The Idea of Biodiversity, a collection of interviews
with the world’s leading conservation biologists. Here they lay their souls bare
and hard science shares the stage with gut feelings.

David Takacs interviews many great names from the New World, including Paul
Ehrlich, Dan Janzen, Gordon Orians, David Pimentel, Peter Raven and Edward
Wilson. But he goes beyond the simple interview by reordering the material from
these discussions under topics, such as the meaning of the term biodiversity,
how it can be measured, and why we place such high value on it today. The
outcome is thought-provoking.

Take definitions, for example. Each interviewee has a different approach.
Hugh Iltis takes the straightforward line, discussing the “number of species” on
the face of the Earth, while to Janzen the variety comprises more than just the
sum of species—”the whole package of genes, populations, species, and the
cluster of interactions that they manifest”—one of the best definitions of
biodiversity I have come across. G. Carleton Ray adds time as a dimension when
he speaks of biodiversity as “the history of biology, the history of life in all
of its forms over the entire time it’s existed on our planet”.

Definitions aside, why do we value biodiversity? Raven takes the attractive
and easily understood view that biodiversity ultimately holds the key to human
prosperity. It is, he feels, an “essential resource for sustainable
development”. Wilson offers what appears superficially to be a similarly
utilitarian outlook: “We really can’t afford to lose any species; they are a
crucible of future human creative effort.”

But there is more to this than the simple question of potential usefulness in
agriculture, pharmacology, medicine and so on. There is the possibility that our
love for nature (biophilia, in Wilson’s lexicon) is embedded in our genes and
arose because it confers a selective advantage for survival. A biophiliac is a
fitter person. Here is an engaging concept that provides a Gaia-style feedback
of environmental preservation.

If this is so, is the role of the ecologist to encourage the development of
global biophilia, encouraging the peoples of the world to find out, as Erlich
suggests, “how good it feels to get out in nature” and to “give them a sense of
wonder”? Does this approach herald the development of new religions, such as the
Deep Ecology movement, or the resuscitation of those elements of traditional
religions in which the natural world is regarded as an inspiration of worship
for a Creator?

Takacs concludes that whatever else the biodiversity debate has done, it has
brought environmental scientists down from their ivory philosophical
towers, forcing them to abandon the “metaphysical notion of an objective,
value-neutral search for knowledge”. This book teaches us a little more of what
it is to be human as well as something of the actual meaning of
biodiversity.

The authors of Ecology, Michael Begon, John Harper and Colin
Townsend, are well equipped to answer this question. They define ecology as the
study of how organisms and their environments match, and the distribution and
abundance of species. This makes it sound like biogeography, perhaps a good
introduction to ecology. But the discipline goes beyond this, examining
interactions between organisms—such as competition, predation and
symbiosis—as well as the dynamics of populations, and how communities
assemble when species shuffle themselves into mutually tolerant groups.
Ecology is organised to follow this logical scheme. If, as evolutionists
suggest, survival is a measure of success, the arrangement has proved its worth
and this book, now in its third edition, can be ranked among the world’s most
highly regarded textbooks on the subject.

Wide-ranging though it is, Ecology could not be expected to cover
every related field in enormous detail. Begon joined forces with Martin Mortimer
and David Thompson to describe one such field in Population Ecology,
now also in its third edition. Here the authors undertake the difficult task of
explaining how populations are regulated and how they interact. The verbal
explanations and simple graphics go some way towards explaining the subject, but
in the end it can only be adequately described and modelled in mathematical
terms. The maths here is relatively friendly, but a familiarity with maths to
A-level standard will help you to get the most out of this book.

Theoretical texts in ecology are all very well, but no amount of mathematical
modelling can replace reliable field data. The puzzle is how this information
can be gathered reliably when conditions in the field are so variable. Field
ecologists generally start by assessing the population levels of different
species. An ecological census, however, involves considerably more than mere
head counts. As we learn from William Sutherland’s Ecological Census
Techniques, whether we are dealing with daisies, dragonflies, diatoms, dace
or dunnocks, sampling is the fundamental skill involved. This manual fully
covers the practical details of many important techniques. Anyone planning a
census programme as part of a conservation monitoring project should consult
this book.

Learning to reason in a scientific manner is an essential part of an
ecologist’s training, but one that cannot be acquired without data from surveys
and experiments. Obtaining such data is often too time-consuming to be
appropriate in school and university classes, but Roland Ennos and Stuart Bailey
have provided an excellent shortcut in Problem Solving in Environmental
Biology. They present selected raw data from a wide range of research
projects, and challenge readers to think their way through to a solution. This
is an exciting and innovative way to teach analytical techniques, and also
introduces the student to a wide range of the concerns now current in ecology.
This is a rich source of ideas for tutorials and numerical analysis
practicals.

What of environmental science, among all these books on ecology? Analysing
the contents of Andrew and Julie Jackson’s Environmental Science serves
to confirm the large amount of overlap between these two disciplines: about half
the book could easily pass as an ecology text. The differences are perhaps most
apparent in a greater emphasis not only on the physical environment, and
particularly chemistry, but also on Homo sapiens. This brand-new
textbook has much to recommend it. The full coverage of environmental chemistry
and the biochemistry of living organisms provides a logical and helpful basis
for later discussions of pollution, toxicology and energy production. The danger
with such a book is that its coverage is so wide that oversimplification is
inevitable. Some ecological areas, such as population ecology and succession,
suffer from this, but the text strikes me as the most successful introduction to
the environmental sciences that I have yet seen.

Living Dangerously, by Heinrich Holland and Ulrich Petersen, could
also be regarded as an introductory environmental science text; but its
subtitle, “The Earth, Its Resources, and the Environment”, gives a clear hint of
a different approach. This is the hard face of environmental studies—the
Earth sciences. Geology, hydrology, mineralogy and oceanography together form
the backbone of this book, and lead up to a look at global change that is
essentially physico-chemical; the human impact on the Earth’s biota is not the
focus here. A very readable book, this American text provides something of a
counterbalance and complement to the Jacksons’ volume, which has a stronger
biological input.

One of the exciting and stimulating, and perhaps worrying, features of the
global environment is that it is constantly changing, perhaps faster now than
for some time. Jonathan Graves and Duncan Reavey’s Global Environmental
Change documents current and projected changes and traces the expected
responses of plants and animals. The overlap with Ecology is very
apparent, although, rather surprisingly, data concerning the current state of
the environment (such as CO₂ levels in the atmosphere and
biogeochemical cycles) are actually more up-to-date in that text than in this
specialised book. The responses of communities to change, including agricultural
ecosystems, are discussed more fully here.

For more detailed information on atmospheric CO₂ levels, climate
change and its consequences, the collaborative work As Climate Changes, edited
by Kenneth Strzepek and Joel Smith for the US Environmental Protection Agency,
is a valuable source book. It tackles specific problems, such as the global food
supply (cereal production may drop by 5 per cent by 2060), a rising sea level (a
rise of 1 metre would put 72 million people at risk in China alone), and global
vegetation types (both forest cover and, surprisingly, desert are set to become
scarcer in this new world).

It is becoming increasingly apparent that our own species is playing a key
role in accelerating the rate of global environmental change, and it is also
evident we will need to adapt our attitudes and management practices to cope
with and control the changes. Soils will alter under new climatic conditions,
and the chemistry of rain will change as a result of pollution. All this will
affect agriculture and nature conservation, as Andrew Taylor, John Gordon and
Michael Usher emphasise in Soils, Sustainability and the Natural
Heritage, which concentrates on the problems that Scotland may experience.
More general aspects of adapting environmental management are covered in
Christopher Barrow’s Developing the Environment, which displays a
global scope and deals with the impact of change in a wide range of areas, such
as agriculture, water management, desertification and waste disposal.

The problems facing our species are too great and too complex for any single
discipline to provide all the answers, and this may well be why those former
subject boundaries are no more. We will still need experts trained in chemistry,
geology, ecology, economics and engineering if the new environmental challenges
are to be tackled, but we also need a broader perspective to appreciate the
roles of these disciplines in problem solving. In other words, we need
environmental scientists. We still know our place, but our horizons have
broadened.