Ecosystem Guidelines for Environmental Assessment

SCEPS
4
Which spatial components of ecological processes have been mapped
For reasons of scale and prioritisation of regional conservation actions, not all spatial components of
ecological processes are mapped in biodiversity plans.
In general, only those large-scale ecological processes deemed to be important for achieving biodiversity
targets at the broad, biome level have been mapped; numerous ecological corridors or vegetation
boundaries that represent more localised but equally important processes at the scale of landscapes
and catchments have not been mapped in most biodiversity plans.
Spatial components of ecological processes have been mapped as follows:
The C.A.P.E. plan mapped selected fixed processes, e.g. edaphic interfaces, sand movement corridors
and riverine corridors. Flexible processes, such as upland-lowland gradients and macro-climatic
gradients, were mapped by finding the most efficient routes or paths for these gradients through intact
natural habitat.
The STEP Conservation Priority Map captures fixed processes as "Process areas" and flexible processes
as "Conservation paths" that provide the core areas for the proposed Mega-conservancy Network.
The SKEP project mapped a separate layer of fixed processes, which includes quartz and gravel
patches, sand movement corridors, and soil interfaces. Flexible processes are shown as arrows
representing upland-lowland gradients and climatic gradients.
The Cape Lowlands Renosterveld Plan mapped a number of ecological processes at 1:50 000 scale,
namely soil type transitions, river corridors, upland-lowland gradients, upland-lowland transitions
(interfaces) and coast-interior gradients.
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Table 4 (see overleaf) summarises the fixed
processes recognised by the CAPE and STEP
projects and provides some examples of their
location. The majority of spatial components of
ecological processes can be mapped either as an
ecological corridor, or as a boundary between two
ecosystems or vegetation types. We suggest that
for the purposes of environmental assessment, it
may be more useful to think in terms of "ecological
corridors and vegetation boundaries" rather than
"spatial components of ecological processes",
which can be difficult to conceptualise.
Spatial components of ecological processes are surrogates
for depicting ecological processes such as pollination.
The conservation of important ecological corridors and vegetation boundaries
At landscape level, environmental assessment practitioners, biodiversity specialists and spatial planners
need to:
BOTANICAL SOCIETY OF SOUTH AFRICA
Refer to existing systematic biodiversity plans in order to determine which important fixed or flexible
ecological processes have been identified and mapped in the affected area. Where these areas have
been mapped, it is essential to ensure that sufficient habitat is set aside and/or managed to support
those ecological processes for which each spatial component was identified.
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