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A system for supporting wetland management decisions.

In South Africa, the loss of wetlands and their associated benefits has been considerable. A need was
identified for a system that, using available information, would assist in achieving a balance between
local, mainly short-term benefits to individuals and spatially wider and longer term benefits to society.
Such a system, termed WETLAND-USE, was developed with the philosophy that:(l) wetlands have
been well demonstrated to supply several indirect benefits to society (e.g. water quality enhancement);
(2) the impact on these benefits can be described on a qualitative basis using field indicators that
characterize the wetland and the disturbance associated with a particular land-use; (3) this information
can be communicated to wetland users, which will contribute to achieving a desired balance, provided
there is an enabling organizational environment and due consideration is taken of the socio-economic
and organizational factors affecting wetland management.
The primary conceptual framework underlying WETLAND-USE was the pressure-state-perceptions-policy
framework, which depicts: the mode of use (i.e. the pressure); how this affects the state of the
system (including its underlying processes and the goods and services it delivers); which in turn shape
the perceptions that ultimately determine the policy pertaining to further use. This cycle is repeated
at a range of organizational levels from local to national and takes place within a particular socioeconomic context.
WETLAND-USE, which was designed for use by fieldworkers, and built using a rule-based, expert
system approach, has two main parts, dealing largely with biophysical and social aspects respectively.
Part 1, which guides the collection of data relating to the state of the wetland, assists in: (1) predicting
the likely impacts of disturbances associated with a proposed land-use (the pressure) on the wetland
state, and (2) providing ongoing management guidelines for particular land-uses. Part 2 assists in: (1)
describing the social, land tenure and policy contexts of the wetland; and (2) establishing and
maintaining organizational arrangements, local policy and management objectives and goals.
Several discrete investigations were required for the development and refinement of WETLAND-USE,
which was done in an iterative fashion. Initial discrete investigations fed into the development of a
prototype system which was refined through evaluation using a questionnaire survey and further
discrete investigations. The revised system was re-evaluated using a fieldworkshop approach and,
based on the performance of the system in the field, it was revised further to produce the final system. In the two initial discrete studies, protocols were developed for characterizing key physical
determinants of wetland functioning, notably: (1) degree of wetness, one of the primary functional
determinants, described in the field using readily identifiable soil morphological indicators (e.g. matrix
chroma and mottles) and (2) landform setting, which strongly influences local flow patterns and lateral
exchange of water and water-borne materials. Graminoid plant species composition and functional
groups (defined in terms of photosynthetic pathway) were then described in relation to the above
physical determinants, together with rainfall, temperature and soil texture, within wetlands spanning
a wide altitudinal range. This revealed that degree of wetness and altitude had the strongest influence
over the vegetation parameters examined.
An investigation into incorporating cumulative impacts into wetland decision making revealed that
consideration should be given to: wetland loss in relation to ecoregions and catchments, and the
relation of change in wetland extent, spatial configuration and context respectively to wetland function.
Current conservation initiatives in KwaZulu-Natal were shown to account poorly for cumulative
impacts on wetlands. Rules of thumb for making such considerations, given severe data limitations,
were developed with reference to the high turn-over of species along the altitudinal gradient observed
in the vegetation study. The "rules" were than applied to a case-study, the upper Mgeni catchment, as
part of an initiative to engage a diversity of stakeholders in wetland information gathering and use.
This resulted in the selection of priority wetlands in the catchment and an examination of the extent
to which integration had been achieved vertically (across hierarchical levels) and horizontally (across
organizations within particular hierarchical levels).
In order to broaden the range of land-uses accounted for by the WETLAND-USE prototype, it was
applied to a communally used wetland, Mbongolwane, and found to account poorly for the traditional
cultivation and vegetation harvesting practices encountered. WETLAND-USE was modified to
include a greater diversity of land-use types as well as enhancing its capacity to allow assessments to
be conducted using the system's general criteria, thereby making WETLAND-USE more robust.
In enhancing the capacity of WETLAND-USE to account for the social and organizational dimension
of wetland management, the involvement of local and outside organizations in influencing wetland
resource use in five sites was examined in relation to predefined frameworks. The sites, Mandlazini
wetland, Mbongolwane wetland, Blood River vlei, Ntabamhlope vlei and Wakkerstroom vlei were
chosen to represent a diversity of social contexts and management authorities. This revealed that in
communally used areas in particular, a wide range of organizations are involved to varying degrees in influencing the use of different wetland resources. The level to which the local organizational
environment contributed to sustainable use varied greatly among wetlands, but in all cases had
important deficiencies: (1) self-governing resource-management organizations were largely lacking
and in communal areas were weakening under contemporary conditions; and (2) although a formal
management system was in place in two of the five wetlands, it was largely absent in the remaining
three. There has been little involvement from extension services in facilitating local policy
development and in promoting alternative land-uses which have less pressure on the state of the
wetland. Local wetland management policy and collaboration among land-owners in wetlands under
multiple separate ownership such as Blood River vlei was identified as being particularly poor.
The evaluations of WETLAND-USE revealed that, in relation to the underlying philosophy of the
thesis, WETLAND-USE had been improved through field application and incorporation of the findings
of the discrete investigations. Nevertheless, important limitations of the study were highlighted,
including: its high level of reliance on expert opinion in the face of a paucity of empirical data relating
to the functioning of local wetlands and their attendant benefits (and how these are affected by
anthropogenic disturbances), and a particularly shallow representation of socio-economic factors. The
identification of these limitations was useful in highlighting key areas for further research. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1999.

Identiferoai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ukzn/oai:http://researchspace.ukzn.ac.za:10413/10263
Date19 December 2013
CreatorsKotze, Donovan Charles.
ContributorsBreen, Charles M., Klug, John R., Hughes, Jeffrey C., O'Connor, Timothy G.
Source SetsSouth African National ETD Portal
Languageen_ZA
Detected LanguageEnglish
TypeThesis

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