152
Systematic conservation planning: past, present and future
combination of vulnerability, ecological condition, and
fi nancial cost of an area might infl uence its priority for
protection. When this occurs, it is important to
acknowledge the conservation cost of not including
these sites within the overall plan. Moreover, the irreplaceability rank of an area will change as individual
areas are designated as part of the conservation area
network. Therefore, the process of identifying irreplaceable sites must be reiterated after each stage,
when new areas are included in a network and others
are removed. Such a process was involved in the
Maputaland study highlighted in Box 6.2 .
6.5 DECISION SUPPORT TOOLS TO
IDENTIFY AND PRIORITIZE NEW
PROTECTED AREAS
As discussed in the introduction to this chapter, the
development and use of systematic planning tools for
designing protected areas is only a recent phenomenon. The early approaches to designing systematic
conservation plans using simple scoring systems (e.g.
Margules & Usher, 1981 ; Smith & Theberge, 1986 )
were perceived to be a great improvement on previous
approaches due to their transparency and repeatability. However, due in large part to technical limitations
of data processing up until the end of the 1980s, these
early systematic conservation planning approaches
did not take into consideration complementarity, nor
did they have the ability to set spatial objectives like
connectivity and spatial compactness (Margules et al .,
1991 ; Pressey, 1997 ).
Over the past decade, decision support tools have
been increasingly used to help inform conservation
planning decisions. Decision support tools are often
computer - based information systems intended to help
decision - makers compile and analyse data to help solve
conservation problems. A range of mathematical techniques have been developed that are incorporated into
these tools (see Box 6.4 and Moilanen et al ., 2009 ). It
is important to note that the use of any decision
support tool, simple or complex, requires properly
defi ned conservation problems.
A common framework for defi ning conservation
priorities is through the use of decision theory. This
framework centres on achieving explicitly stated
objectives while acknowledging constraints on conservation actions and the levels of uncertainty involved
within the decision process. In Table 6.2 , we outline a
conserving ecosystem services versus the conservation
of other biodiversity features (K.A. Wilson et al ., 2009 )
and then seek to maximize the overall benefi t that is
derived.
6.4.4 Achieving fl exibility
As we have discussed throughout this chapter, the
selection and creation of new protected areas in a
network is not a simplistic, one - off process. Protected
area networks have to be accepted socially and politically, and it is therefore of critical importance that
there should be several alternatives available when
a systematic conservation plan is developed. These
alternatives mean that the plan is fl exible (Pressey
et al ., 1993 ). It must be clear, however, why areas
are selected and why some areas are not, and hence
transparency is a clear part of fl exibility (Nicholls &
Margules, 1993 ).
Measuring the ‘ irreplaceability ’ of sites is arguably
the commonest way to show fl exibility in a systematic
conservation plan. The irreplaceability of a site refl ects
the importance of including that site in the protected
area network if all conservation objectives are to be
achieved (Pressey et al ., 1994 ; Ferrier et al ., 2000 ).
Irreplaceability can be viewed in two contexts: the likelihood that an area is necessary to achieve conservation objectives for the features it contains; or the extent
to which the options for achieving conservation objectives are reduced if the area is unavailable for
conservation.
In systematic conservation planning, a completely
irreplaceable area is essential for a plan to meet its
conservation objectives, whereas an area with a very
low irreplaceability can be substituted by other sites.
For example, when planning a reserve system in a
landscape, you may fi nd that some areas are completely unique or have been altered to such as extent
that the last remaining sites are highly irreplaceable. If
there is a risk of these areas being lost to threatening
processes, then it might be a large loss for biodiversity
conservation in that region. Consequently, irreplaceability can be used as a measurement of conservation
value.
It is important to note that although irreplaceability
can help determine which areas are priorities for
conservation, other constraints and considerations
may mean that areas with lower irreplaceability are
more suitable for conservation. For example, some
Systematic conservation planning: past, present and future
combination of vulnerability, ecological condition, and
fi nancial cost of an area might infl uence its priority for
protection. When this occurs, it is important to
acknowledge the conservation cost of not including
these sites within the overall plan. Moreover, the irreplaceability rank of an area will change as individual
areas are designated as part of the conservation area
network. Therefore, the process of identifying irreplaceable sites must be reiterated after each stage,
when new areas are included in a network and others
are removed. Such a process was involved in the
Maputaland study highlighted in Box 6.2 .
6.5 DECISION SUPPORT TOOLS TO
IDENTIFY AND PRIORITIZE NEW
PROTECTED AREAS
As discussed in the introduction to this chapter, the
development and use of systematic planning tools for
designing protected areas is only a recent phenomenon. The early approaches to designing systematic
conservation plans using simple scoring systems (e.g.
Margules & Usher, 1981 ; Smith & Theberge, 1986 )
were perceived to be a great improvement on previous
approaches due to their transparency and repeatability. However, due in large part to technical limitations
of data processing up until the end of the 1980s, these
early systematic conservation planning approaches
did not take into consideration complementarity, nor
did they have the ability to set spatial objectives like
connectivity and spatial compactness (Margules et al .,
1991 ; Pressey, 1997 ).
Over the past decade, decision support tools have
been increasingly used to help inform conservation
planning decisions. Decision support tools are often
computer - based information systems intended to help
decision - makers compile and analyse data to help solve
conservation problems. A range of mathematical techniques have been developed that are incorporated into
these tools (see Box 6.4 and Moilanen et al ., 2009 ). It
is important to note that the use of any decision
support tool, simple or complex, requires properly
defi ned conservation problems.
A common framework for defi ning conservation
priorities is through the use of decision theory. This
framework centres on achieving explicitly stated
objectives while acknowledging constraints on conservation actions and the levels of uncertainty involved
within the decision process. In Table 6.2 , we outline a
conserving ecosystem services versus the conservation
of other biodiversity features (K.A. Wilson et al ., 2009 )
and then seek to maximize the overall benefi t that is
derived.
6.4.4 Achieving fl exibility
As we have discussed throughout this chapter, the
selection and creation of new protected areas in a
network is not a simplistic, one - off process. Protected
area networks have to be accepted socially and politically, and it is therefore of critical importance that
there should be several alternatives available when
a systematic conservation plan is developed. These
alternatives mean that the plan is fl exible (Pressey
et al ., 1993 ). It must be clear, however, why areas
are selected and why some areas are not, and hence
transparency is a clear part of fl exibility (Nicholls &
Margules, 1993 ).
Measuring the ‘ irreplaceability ’ of sites is arguably
the commonest way to show fl exibility in a systematic
conservation plan. The irreplaceability of a site refl ects
the importance of including that site in the protected
area network if all conservation objectives are to be
achieved (Pressey et al ., 1994 ; Ferrier et al ., 2000 ).
Irreplaceability can be viewed in two contexts: the likelihood that an area is necessary to achieve conservation objectives for the features it contains; or the extent
to which the options for achieving conservation objectives are reduced if the area is unavailable for
conservation.
In systematic conservation planning, a completely
irreplaceable area is essential for a plan to meet its
conservation objectives, whereas an area with a very
low irreplaceability can be substituted by other sites.
For example, when planning a reserve system in a
landscape, you may fi nd that some areas are completely unique or have been altered to such as extent
that the last remaining sites are highly irreplaceable. If
there is a risk of these areas being lost to threatening
processes, then it might be a large loss for biodiversity
conservation in that region. Consequently, irreplaceability can be used as a measurement of conservation
value.
It is important to note that although irreplaceability
can help determine which areas are priorities for
conservation, other constraints and considerations
may mean that areas with lower irreplaceability are
more suitable for conservation. For example, some