32
Baselines, patterns and process
et al ., 2004 ), even if highly uncertain (Chapters 4 , 7 ;
Ara ú jo et al ., 2005b ), suggest that it will be diffi cult to
retain the existing composition of species in reserves
(especially small ones) and the wider landscape (e.g.
Ara ú jo et al ., 2004a ; Hannah et al ., 2007 ) and that
conservationists will have no choice other than to
focus on restoring and strengthening ecological process
so that natural systems can respond effectively to
climate change.
Responses may include facilitating movement of
species between reserves or, more passively, relying on
the evolutionary responses of species in situ . In some
respects, this is merely an extreme example of a more
general problem for compositionalist approaches to
conservation – how best to conserve systems that are
intrinsically dynamic?
3.3 BALANCE VERSUS FLUX
In recent decades, there has been something of a paradigm shift in ecology, from an equilibrium or ‘ balance
of nature ’ world view, to one of nature in fl ux, or not
at equilibrium. This shift in perspective has profound
implications for the way ecosystems are understood
and managed, although whether it truly constitutes a
paradigm shift is moot. Such dualities have typically
existed in parallel as binary opposites ( sensu Eagleton,
1983 ; cited in Crisci & Katinas, 2009 ), such that for a
while one perspective is central to the discipline, and is
privileged, while the opposite member of the pair is
marginalized. This representation perhaps better captures the character of such debates than the notion
that one view was universally held and then universally discarded in a once - and - for - all paradigm shift.
Along these lines, it is almost certainly a mistake to
conceptualize ecological systems as either wholly equilibrial or entirely non - equilibrial in nature (e.g. see
discussion in Whittaker & Fern á ndez - Palacios, 2007 ).
The equilibrium paradigm dominated ecology for
most of the 20th century, but its origins can be traced
far back in time to ancient Greek and Judaeo - Christian
traditions (Egerton, 1973 ; Wu & Loucks, 1995 ).
Nature was conceptualized as a stable and unchanging
entity, a view that underpinned infl uential ecological
ideas such as the climatic climax, the logistic growth
equation and ideas of carrying capacity (Bartels &
Norton, 1993 ).
These apparently diverse and unrelated ideas
describe vegetation assemblages and populations as
which are maintained by mimicking medieval farming
practices (Ladle & Jepson, 2010 ).
In reality, most conservationists have both compositionalist and functionalist tendencies and it may be
better to think of individuals and organizations as
occupying part of a functionalist/compositionalist
continuum (Callicott et al ., 1999).
Neither
compositionalist
nor
functionalist
approaches are without drawbacks. A pure functionalist approach may lead to many rare or endangered
species being replaced by ‘ weedy ’ species that occupy
the same ‘ role ’ within the ecosystem with equal or
superior facility. In addition, assessments of ecosystem
processes are highly scale dependent, and a functionalist approach may simply be ineffective for smaller
reserves such as many of those found in abundance
in some industrialized European nations. Conversely,
a compositionalist approach, by largely neglecting
process, may necessitate huge and continuing investment of resources to maintain the desired assemblages.
Furthermore, a compositionalist approach is likely to
have far less traction with the polity in countries where
populations are heavily reliant on natural resource
extraction or ecosystem services or both.
Williams and Ara ú jo (2002) have argued that the
two approaches must be linked for conservation to be
successful. This makes sense, because the persistence
of species and the sustainability of ecological processes
are largely dependent upon one another, even if the
two are not wholly interchangeable. Logically, any
such linkage should begin from the compositionalist
perspective, because the maintenance of ecological
processes (including the politically and economically
important ‘ ecosystem services ’ ) depends upon the conservation of the ecosystem components.
A linkage between compositionalist and functionalist approaches will necessarily have an explicit spatial
component, with smaller, more intensively managed
areas of compositionalist interest being embedded
within larger areas or landscapes that are managed
and monitored from a functionalist perspective. In
Western European countries, this typically takes the
form of a semi - agricultural landscape containing a
variety of small nature reserves, or semi - natural areas
that are managed for a variety of conservation goals,
including conservation of rare species and recreation.
A further challenge for 21st century conservationists will be maintaining ecological pattern and process
in the face of anthropogenic climate change. The predictions of most climate envelope models (e.g. Thomas
Baselines, patterns and process
et al ., 2004 ), even if highly uncertain (Chapters 4 , 7 ;
Ara ú jo et al ., 2005b ), suggest that it will be diffi cult to
retain the existing composition of species in reserves
(especially small ones) and the wider landscape (e.g.
Ara ú jo et al ., 2004a ; Hannah et al ., 2007 ) and that
conservationists will have no choice other than to
focus on restoring and strengthening ecological process
so that natural systems can respond effectively to
climate change.
Responses may include facilitating movement of
species between reserves or, more passively, relying on
the evolutionary responses of species in situ . In some
respects, this is merely an extreme example of a more
general problem for compositionalist approaches to
conservation – how best to conserve systems that are
intrinsically dynamic?
3.3 BALANCE VERSUS FLUX
In recent decades, there has been something of a paradigm shift in ecology, from an equilibrium or ‘ balance
of nature ’ world view, to one of nature in fl ux, or not
at equilibrium. This shift in perspective has profound
implications for the way ecosystems are understood
and managed, although whether it truly constitutes a
paradigm shift is moot. Such dualities have typically
existed in parallel as binary opposites ( sensu Eagleton,
1983 ; cited in Crisci & Katinas, 2009 ), such that for a
while one perspective is central to the discipline, and is
privileged, while the opposite member of the pair is
marginalized. This representation perhaps better captures the character of such debates than the notion
that one view was universally held and then universally discarded in a once - and - for - all paradigm shift.
Along these lines, it is almost certainly a mistake to
conceptualize ecological systems as either wholly equilibrial or entirely non - equilibrial in nature (e.g. see
discussion in Whittaker & Fern á ndez - Palacios, 2007 ).
The equilibrium paradigm dominated ecology for
most of the 20th century, but its origins can be traced
far back in time to ancient Greek and Judaeo - Christian
traditions (Egerton, 1973 ; Wu & Loucks, 1995 ).
Nature was conceptualized as a stable and unchanging
entity, a view that underpinned infl uential ecological
ideas such as the climatic climax, the logistic growth
equation and ideas of carrying capacity (Bartels &
Norton, 1993 ).
These apparently diverse and unrelated ideas
describe vegetation assemblages and populations as
which are maintained by mimicking medieval farming
practices (Ladle & Jepson, 2010 ).
In reality, most conservationists have both compositionalist and functionalist tendencies and it may be
better to think of individuals and organizations as
occupying part of a functionalist/compositionalist
continuum (Callicott et al ., 1999).
Neither
compositionalist
nor
functionalist
approaches are without drawbacks. A pure functionalist approach may lead to many rare or endangered
species being replaced by ‘ weedy ’ species that occupy
the same ‘ role ’ within the ecosystem with equal or
superior facility. In addition, assessments of ecosystem
processes are highly scale dependent, and a functionalist approach may simply be ineffective for smaller
reserves such as many of those found in abundance
in some industrialized European nations. Conversely,
a compositionalist approach, by largely neglecting
process, may necessitate huge and continuing investment of resources to maintain the desired assemblages.
Furthermore, a compositionalist approach is likely to
have far less traction with the polity in countries where
populations are heavily reliant on natural resource
extraction or ecosystem services or both.
Williams and Ara ú jo (2002) have argued that the
two approaches must be linked for conservation to be
successful. This makes sense, because the persistence
of species and the sustainability of ecological processes
are largely dependent upon one another, even if the
two are not wholly interchangeable. Logically, any
such linkage should begin from the compositionalist
perspective, because the maintenance of ecological
processes (including the politically and economically
important ‘ ecosystem services ’ ) depends upon the conservation of the ecosystem components.
A linkage between compositionalist and functionalist approaches will necessarily have an explicit spatial
component, with smaller, more intensively managed
areas of compositionalist interest being embedded
within larger areas or landscapes that are managed
and monitored from a functionalist perspective. In
Western European countries, this typically takes the
form of a semi - agricultural landscape containing a
variety of small nature reserves, or semi - natural areas
that are managed for a variety of conservation goals,
including conservation of rare species and recreation.
A further challenge for 21st century conservationists will be maintaining ecological pattern and process
in the face of anthropogenic climate change. The predictions of most climate envelope models (e.g. Thomas