The key area concept in nature conservation has been admirably spelt out in Cmd 7122
(Ministry of
Town and Country Planning, 1947) in a discussion of the main purposes of a series of National
Nature Reserves (NNRs). The need to represent in such a series the countrywide diversity in nature
conservation interest according to the range of human concern attaching to this is expressed as
follows (ibid., para. 50):
to
preserve and maintain as part of the nation's natural heritage places which can be
regarded as reservoirs for the main types of community and kinds of wild plants and animals
represented in this country, both common and rare, typical and unusual, as well as places
which contain physical features of special or outstanding interest. These places must be
chosen so far as possible to enable comparisons to be made between primitive or relatively
undisturbed communities and the modifications introduced by varying degrees of human
interference; typical and atypical physical conditions; distinctive characteristics imposed
upon communities and species by differences in geographical position, physiography,
climate, geology and soil, both within the main physical regions and in the transitional
zones between them; the behaviour of species or communities living within and at the
margins of their geographical distribution or their ecological tolerance. The series as a whole
should take fair account of the varied requirements and interests of the several different lines
of scientific approach: the systematic study of particular groups of species; studies of
communities or species in relation to their environment; of the rise and fall in population
numbers; of breeding structures of populations and the way in which inherited variations are
distributed; of geographical distribution; of plant and animal behaviour; of the climatic and
microclimatic conditions which so largely govern the distribution of organisms; of soils; of
the rocks and the fossils they hold; and of the physical forces which shape the surface of
the land; as well as general evolutionary studies. Considered as a single system, the
reserves should comprise as large a sample as possible of all the many different groups of
living organisms, indigenous or established in this country as part of its natural flora and
fauna; and within them the serious student, whatever his bent and whether he be
professional or amateur, should be able to find a wealth of material and unfailing interest.
This lucid statement emphasised the range of scientific value inherent in the features
which were to
be thus conserved and the exposition went on to elaborate the functions of the sites in providing for
research, educational and ' amenity' use. It was stressed that such sites would usually need
careful management if their scientific and nature conservation value was to be maintained, and that
this in itself would often require research in depth. An extension of the 'open-air laboratory' notion
was that some sites might have to be acquired specially as research areas, so that experiments of
a kind destructive to other interests might be performed. Experimentation was envisaged as
including the deliberate re-creation of new or lost habitats. The research was understood to serve
the advancement of science, and the giving of advice on land management elsewhere (especially in
National Parks). It should also serve as a means to an end in learning how to manage the sites
themselves. The 'living-museum' concept was related more to the educational function and to
provide ' for that considerable section of the public who without any scientific interests can derive
great pleasure from the peaceful contemplation of nature'.
The above quotation makes it clear that the key areas were intended to cater for the
wants of those
with relatively simple interests in wildlife, as well as for the more esoteric needs of the scientist,
and the aesthetic element is clearly stated. Within the range of broadly cultural functions, scientific
purpose and maintenance of the 'natural heritage' were stressed above all. The conservation of key
areas was thus held to be concerned especially with the advancement of knowledge and
understanding, both in the individual and in society, and with human fulfilment in a non-material
sense.
The present review accepts and endorses this rationale, but is concerned to examine
in greater
depth how it is translated in practice into criteria to guide the selection of the key sites.
It was emphasised further in Cmd 7122 that 'It has proved necessary under the conditions
now
obtaining in this country to concentrate in the first instance on saving places which are still known
to possess high scientific value . . .'. The experience of the last 25 years has reinforced this view.
It
is now accepted that human impact in Britain is so universal and pervasive that no area of land or
water is safe from developments destructive or deleterious to their nature conservation interest,
unless deliberate measures are taken to ensure that they remain unmodified. There is, in fact, an
even stronger realisation now that, since many sites are both irreplaceable and severely at risk,
serious and permanent loss is imminent if adequate safeguards are not taken or maintained.
Present concern in the Review has thus been to identify these irreplaceable sites
before it is too
late. The overall intention has been to delineate the most valuable and vulnerable part of the
national capital of wildlife and habitat, plus an additional element which is adequately representative
of other major semi- natural ecosystems. The process of selection presupposes that nature
conservation interest is spread throughout Britain, but unevenly and discon-tinuously in a
geographical sense, and variably also in terms of intrinsic quality. Graham first proposed a
classification of land into categories of different quality according to its potential for agriculture,
and
the zoning of land according to its capability for one purpose or another is now widely accepted in
planning. The Nature Conservation Review represents an attempt to identify the highest quality land
of Britain in terms of nature conservation interest, but also indicates how the concept of differential
quality could be made the basis for a more comprehensive zoning of this interest.
The term 'highest quality' obviously implies that the 'best' examples of the range
of ecosystems
should, by preference, be chosen for the national series of key sites. Yet the definition of 'best'
in
terms of specific, measurable qualities is an extremely difficult task, and often involves many-sided
value judgements in which standards are essentially relative and not absolute. Moreover, the
concepts of 'best' or 'most important' may involve a considerable degree of unusualness, since they
connote the acme of quality. There is also some need to represent the typical or ordinary rather
than the exceptional. The series of key sites will thus be a mixture of the scarce and unusual and
the typical or common examples of ecosystems; moreover, there may be intermediate cases or
both types may be represented within the same site.
While criteria for selection of sites must depend to a large extent on evaluation
of their intrinsic
qualities in relation to the range of human interest, there is an over-riding need to take account of
the vulnerability of the features themselves. It is therefore necessary to consider where human
impact bears most heavily on wildlife and its habitat; importance attaches especially to species,
communities and habitats which have been most heavily reduced by past human influence, to
those most likely to disappear if no remedial action is taken, and to those which are least readily
replaced once they have been lost or badly damaged. The exceptional sites will thus tend to
predominate in the selection, for these are the places whose destruction would cause the greatest
loss to nature conservation. The typical sites are by definition usually more widespread than the
exceptional, and there is more chance that examples will escape serious modification, or that they
can be re-created elsewhere as opportunity allows. Even so, it is important that the national series
of key sites contains major reference points within the field of ecological variation, as 'type'
examples of significant ecosystems, communities and species aggregations. Where sites chosen
for their special attributes do not also contain more ordinary and typical features, it is necessary
to
choose additional sites, to ensure that the whole series is adequately representative. The notion of
a 'representative series' should not, however, be taken too far, for it could lead to the selection
of
sites which are unimportant in a national context.
The criteria for assessment of quality of an ecosystem must express the range of human
concern
contained within the whole concept of nature conservation. In other words, values have to be
attached to ecosystem features according to their significance to definable human interests. Each
criterion is thus a real attribute transformed by a value judgement about function into an abstract
quality of dual character. As an example, diversity can be measured as an attribute, and as such
has neutral value; but because high diversity usually has more interest to biologists than low
diversity, the actual value measured can be used as an index of quality in this respect. But nature
conservation is a complex subject, expressing a range of interests each with its own scale of
values, e.g. what is important to a geneticist may not be important to a field naturalist, and vice
versa.
The requirements for the 'open-air laboratory' will often be different from those
for the 'living
museum'. Some criteria involve more subjective concepts of quality than others, and their attributes
are less precisely quantifiable. An additional problem in the definition of criteria is that the human
interests which they reflect not only cover a wide range of viewpoint, but also may undergo change
in the future. Preferably they should therefore acknowledge potential as well as present values.
These criteria, and the way in which they are applied, are discussed later.
The choice of key sites involves the comparative assessment of a large number of different
examples of ecosystems, to identify those of high enough quality to be accepted for the national
series. The process depends on an awareness of the range of variation in British ecosystems,
within which certain 'types' can be identified. This in turn requires that the extensive knowledge of
real plant and animal communities in the field be translated into some kind of abstract framework
through a classification of data. Only through adequate field survey is it possible to be confident
that this ecological framework of reference is reasonably complete, and that all the important sites
are considered in making the selection of 'type' examples of natural and semi-natural ecosystems.
Sites of similar character, corresponding to a certain type or combination of types,
are compared
with each other and judged in terms of accepted criteria, so that relative status can be assigned to
each. There is a steady process of sifting, to identify the most promising or obviously outstanding
sites so that, finally, it is possible to decide that one site in particular is preferred above all
others.
Often, however, the type which is being considered for representation is so broad and variable that
it can only be adequately represented by a series of specific sites. For instance, oakwood is an
important semi-natural vegetation type in Britain, but woods with the common feature of oak
dominance differ enormously in other ecological features according to differences in climate (on
both a local and regional scale), topography, soil and management. It is therefore necessary to
choose a series of different oakwood sites which adequately represent this range of variation.
A still more difficult aspect of the selection process concerns the extent and number
of the
preferred sites. In Cmd 7122 the highest importance was attached to safeguarding examples of
major ecosystems as scientific study areas; it was felt that this selection, forming a NNR series,
should include important 'museum-piece' examples of types not easily re-created or restored, but
that the areas concerned should not be too large, nor the number of sites greater than a judiciously
chosen minimum. It was, however, envisaged that important larger areas, e.g. of upland
ecosystems, would be adequately safeguarded by other proposed measures which were not, in
fact, later adopted. The failure to include in subsequent legislation the National Park Reserves,
Scientific Areas and Conservation Areas proposed in Cmd 7122 at once made the original list of
proposed NNRs inadequate.
Subsequent developments have involved a growing realisation that, on the one hand,
the national
strategy for nature conservation must consist of much more than the safeguarding of a hard core of
key sites and, on the other, that wildlife and its habitats in Britain are under evergrowing pressure
of
an order greater than that envisaged a quarter of a century ago. It is therefore natural and desirable
that the purpose of safeguarding key sites should have advanced beyond the idea of a minimum
sample of relatively small areas to the notion that the series should be as large as can be allowed
by available resources. Cmd 7122, para. 50, itself contains the statement that 'Considered as a
single system, the reserves should comprise as large a sample as possible of all the many
different groups of living organisms, indigenous or established in this country as part of its natural
flora and fauna.' It is probable that 'reserves' here was intended to mean all categories of area
safeguarded for their nature conservation interest, but the general view is clear and supports that
just expressed.
The problems and decisions relating to ' as large a sample as possible' of key sites
will be
discussed in the following amplification of the selection process.
