Watershed Management Services
Catchment management is the applied management of a catchment area aimed at the sustainable delivery of its
resources. To achieve this, plans, programmes and projects need to be implemented to sustain and enhance catchment
functions that affect the plant, animal, and human communities within a watershed boundary.
Features of a catchment that agencies seek to manage include water supply, water quality, drainage, storm water runoff,
water rights, and the overall planning and utilisation of resources. Landowners, land use agencies, storm water
management experts, environmental specialists, water use surveyors and communities all play an integral part in the
management of a catchment.
But planning together is vital across the landscape - including fire management, vegetation management and catchment
Steps in Catchment Planning and Implementation:
- Build partnerships
- Characterise the catchment
- Finalise goals and identify solutions
- Design and implement programmes
- Implement the catchment plan
- Measure progress and make adjustments
Integrated catchment management is a subsection of environmental management that approaches sustainable resource
management from a catchment perspective. This is in contrast to a piecemeal approach that artificially separates land
management from water management.
Integrated catchment management recognises the existence of ecosystems and their role in supporting flora and fauna,
providing services to human societies and regulating the human environment. Integrated catchment management seeks
to take into account complex relationships within those ecosystems: between flora and fauna, between geology and
hydrology, between soils and the biosphere, and between the biosphere and the atmosphere. Integrated catchment
management recognises the cyclical nature of processes within an ecosystem, and values scientific and technical
information for understanding and analysing the natural world.
Fynbos is a fire-driven biome, fire being necessary to cycle nutrients and rejuvenate the vegetation. Fire, therefore, will
happen, whether it is man induced or as a result of natural incendiaries such as lightning. In fynbos and grassland
catchments, it is imperative to manage fire not only for the renewal of the vegetation but also for the management of runoff.
Climate change has affected fire behaviour in yet to be researched and understood ways, and fires have burnt more
frequently over larger areas during the last 10 years than in the previous 30.
In the Overberg district of the Western Cape, this has resulted in not only tragic loss of life and infrastructure, but also loss
of livelihoods, displacing hundreds of rural flower pickers and their families into urban squalor. Wildfires have contributed
significantly to the migration of people from the rural areas into urban residential areas with the accompanying social ills.
Too frequent fires has also resulted in the loss of biodiversity through fynbos vegetation that has not yet produced seed.
In the case of most Proteas, plants will only flower and set seed after a number of years, depending on species, soil
depth and aspect and rainfall. If these plants are burnt before at least 50% have flowered three times or more, insufficient
seed is available to replace the adults. In some areas in the fynbos mountains of the Western Cape, large areas have
been burnt before the plants could flower and set seed, leading to decreased biodiversity of species.
Climate change, the increase in temperatures coupled with increased CO2 levels, will promote the growth of certain
species in the fynbos biome. A shift in rainfall toward spring and summer rains will further promote understory growth of
grasses and sedges. As a result, fires seem to be sustained later into winter and are hotter, being driven by the strong
winds of the Western Cape. This creates difficult and dangerous situations.
And yet the solution is so easy: strategic fire management as part of catchment management. Obviously the cost of
implementing such strategies is a major factor, but more than this is the barrier of coordinated public-private sector effort.
All the ingredients are there to face these challenges: dynamic municipalities and fire services, the Working For
programmes and private will.
Rory Allardice Environmental is proficient in dealing with all sectors and planning and facilitating
strategic fire breaks and block burns in catchment areas.
- Fire breaks
- Block burns
- Vegetation Management
The first active vegetation management activity other than fire management that comes to mind is that of invasive alien
plant infestation management. However, flower picking must also be managed to ensure the continuation and promotion
of useable species for the industry.
The effects of higher CO2 are well known in the tunnel farming industry where levels of 1000 ppmv are achieved to
increase and speed up production. Our present atmospheric levels are around 360 ppmv, having increased from about
330 ppmv over the last 50 years or so. That's pretty insignificant considering that CO2 is the primary plant food and
nothing can survive without it, and that .0001% of carbon is present in the atmosphere. The rest is trapped in the earth,
rocks, dead and living organisms.
We do not yet know the effects of higher CO2 levels on the fynbos in general, but we can hypothesize by using the
research available on CO2 effects on plant families. C4 plants, mainly grasses, out compete C3 plants at higher
temperatures, and therefore may have a larger impact on fynbos going into climate change.
Alien Infestation Management
Alien plant infestation threatens the natural health of fynbos by out-competing and displacing indigenous species, and by
producing higher temperatures when they burn. The burning cycle for most alien species is shorter than that for fynbos,
leading to more frequent fires and loss of fynbos species. Alien plants usually require more water to survive and have
longer tap roots that indigenous species utilising ground water, thereby affecting seeps, sponges and fountains. Alien
vegetation is considered the greatest threat to fynbos diversity by some specialists. Climate change with accompanying
higher carbon dioxide levels seems to have stimulated the growth of some alien acacia species, exacerbating the
Alien plant control requires fine-tuned planning in conjunction with agricultural activities and fire management. In certain
situations it is advantageous to the landowner to manage the alien vegetation as a woodlot, deriving benefit through
firewood or biomass used to fuel energy plants. It is critical where these woodlots are situated in catchments so as not to
affect biodiversity and water production. This may well be the case in a municipal commonage where the community is
reliant on the woodlot for building material and primary energy to heat and cook with. A fire through the woodlot would
devastate the community. A number of alien species, for example the Australian Acacias, are stimulated by fire and
require immediate follow-up after a fire. Fire may be a good initial clearing tool in old fynbos but may generate an
exponential increase in the alien vegetation cover unless follow-up is part of the plan.
Agricultural activities in the most part promote alien spread. Animals hoof action and spread of dung carry alien seed into
previously clean areas, and if these areas are of limited financial value to the landowner, he cannot spend money
clearing and maintaining them. Catchments are generally poor agricultural areas and therefore have been neglected as
far as alien vegetation management is concerned. Generally, weeds (aliens included), inhabit disturbed areas. Areas
that have seen mechanical disturbance such as quarries, roads, and water works are usually infested with alien plant
species and act as seed banks for further spread in catchments. These areas must be carefully managed to ensure that
this does not happen.
Water is probably the most important product supplied by a catchment and people will always be concerned about the
quality of that water. Pollution is therefore a major factor. Pollution can be point source or non-point source and it's
important to identify and apply reduction management for both. The use of certain herbicides in wetlands is inadvisable
because of their accumulative effect and seepage into the ground water consumed by people and animals away from
the wetland. Spray drift from areas outside of the catchment may also contribute to pollution within the watershed and
therefore requires effort outside of the watershed boundaries.
PHONE +27 (0) 82 929 9904
T +27 (0) 82 929 9904
F +27 (0) 86 541 1682
© 2012 - 2016 www.raenvironmental.co.za
"My mission is to promote biodiversity conservation and
sustainable systems which will in turn ensure the
well-being of mankind."
Assessor & Workplace Development Facilitator THETA accredited.
Recent: "Greening the Collage". Industrial "greening", solar
panels, heat pumps, sewerage systems, clean water filters etc.
together with the equatorial forest surrounding the Nyungwe
National Park ... read more