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A
FRAMEWORK OF SUSTAINABILITY INDICATORS FOR
DURBAN
Despite the research already
conducted for sustainability indicators a comprehensive list
of indicators does not exist. There does exist parameters that
define a "good indicator", including that indicators should be
(Meadows, 1998):
- Clear in value – showing no
uncertainty in trend
- Clear in content – presenting
easily understandable units that make sense
- Compelling – interesting,
exciting and suggestive of effective action
- Policy relevant
- Feasible – measurable at
reasonable cost
- Sufficient – not too much
information to understand but adequate to provide a suitable
picture of the situation
- Timely – compilable without long
delays
- Appropriate in scale – not over
or under aggregated
- Democratic – people should have
input to indicator choice and have access to results
- Supplementary – should include
what people cannot measure for themselves
- Participatory – make use of the
information that people can measure for themselves
- Hierarchical – in order for a
user to delve down into the details that are necessary
- Leading – so that they can
provide information to act on
- Tentative – so that they are up
for discussion, learning and change.
When this list is closely examined
it becomes apparent that it is virtually impossible to come up
with the "perfect" indicator. There are, however, many
frameworks for monitoring and reporting of indicators. A
causal framework is currently the most widely accepted. Causal
frameworks classify environmental problems broadly in terms of
the overall causal flow of human-environment
interactions.
The Organization for Economic
Co-operation and Development's "pressure-state-response" (PSR)
model (OECD, 1993) is widely used for organising environmental
information. Human activities are seen as producing
pressures (e.g. pollutant releases) that can
induce changes in the state of the
environment (e.g. changes in ambient pollutant levels).
Society then responds to changes in pressures
or state with environmental and economic policies and
programmes intended to prevent, reduce or mitigate pressures
and / or environmental damage. The PSR framework is probably
the most widely accepted causal framework at present, largely
because of its simplicity and the fact that it can be applied
at any scale.
While cause-effect relationships are difficult to
establish, environmental decision-making relies on assumptions
about such linkages in order to determine appropriate
management responses. Analyses that show relationships among
variables (e.g. environmental conditions and potential causes)
generally have the most meaning for environmental
decision-makers. To address this need for information about
relationships in decision-making, the US Environmental
Protection Agency added a fourth category to the PSR
Framework, termed "Effects", defined as indicators
of relationships between two or more pressure, state, and or
response variables. Click here to
view a graphical representation of the
Pressure-State-Response/Effects framwork.
Pressures
Pressures on the
environment can be divided into three types: underlying
societal pressures, indirect pressures, and direct pressures:
- Underlying societal
pressures are the social and technological forces that
motivate or otherwise drive human activities, which in turn
cause many of the direct biophysical pressures on the
environment. E.g. human population growth, social structure,
technology changes, cultural attitudes, and basic policies
that drive economic activity.
- Indirect pressures
are the human activities (mostly economic activities,
e.g.: agriculture, mining, manufacturing, transportation,
consumption by individuals and households) related to human
sustenance or the improvement of human welfare, plus natural
processes and factors (e.g., population and nutrient cycles,
meteorological events, earthquakes, volcanic eruptions,
etc.), many of which interact with human pressures and some
of which act alone to create direct biophysical pressures on
the environment.
- Direct pressures are the
actual biophysical inputs and outputs that may exert
immediate stress on ecosystems. These include anthropogenic
pollutant releases, resource harvesting and extraction, land
use changes, and species introductions. Also, the background
flows (not the same as ambient levels or conditions) of
those natural stressors that are greater than or comparable
to the anthropogenic pressures (perhaps within 1-2 orders of
magnitude, if smaller).
State of the Environment
This is
concerned about changes in or effects on Valued Environmental
Attributes (VEAs) that
ultimately drive environmental decision-making. VEAs refer to
those aspects of ecosystems (and human health and
environmentally-related welfare, as discussed below) that are
considered by society to be important and potentially at risk
from human activities and/or natural hazards. It is important
to note that the societal value of ecosystems cannot be
determined solely on the basis of public preference, since
many people may be unaware of the value ultimately derived
from ecosystem services. Over time, the number of ecological
attributes found to be essential for maintaining the viability
and stability of the biosphere (and therefore, economies and
cultures) has continued to grow.
VEAs can range from individual valued species (e.g., the
elephant), to landscape scale functions (e.g., hydrology of
wetland systems), to global scale features (e.g., the
stratospheric ozone layer's ability to filter ultraviolet
radiation). Some VEAs are clearly already enshrined in
existing legislation. At present, no generally accepted,
comprehensive classification of ecological attributes in
policy-relevant terms exists.
An example of the complexity of selecting and managing for
indicators is reflected in the example below. Through community participation exercises it has been
determined, in this example, that fish are considered to be a
valued environmental attribute in a river in Durban. The fish
are valued for their aesthetic value and as a source of food.
In terms of sustainability of that resource it is necessary to
ensure population numbers. The following indicators may be
applied to assess the sustainability of this system at a
catchment level (please note that this is not a comprehensive
list of all the relevant indicators)
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PRESSURE |
STATE |
RESPONSE |
- Growth of informal communities adjacent to the
river course
Domestic
consumption of water reserve
Industrial
effluents
Fisherpersons per unit
area of stream
% land lost to erosion as
a percentage of total surface area |
Incidence of fish
kills/unit effluent
Fish caught per unit of
fishing effort
Quality of river
water
Annual abstraction of
river water (%of reserve) |
Expenditure on
pollution control staff and equipment
Expenditure for the
provision of sanitation facilities for upstream
communities |
PROVISIONAL APPROACH FOR
SUSTAINABILITY INDICATORS IN DURBAN
REFERENCES
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