Page 18 - LandscapeSAIssue113

ENVIRONMENTAL FEATURE

weirs or other structures. Keep in mind that
re-shaping of riverbanks can only be done
through authorisation from the Dept. of
Environmental Affairs and an application
to do so can only be made by a registered
environmental consultant or a freshwater
specialist.

In terms of planting methodology or
‘soft’ rehabilitation, Intaba has found that
a combination of sowing of indigenous
seeds and planting seedlings gives the
best results. This also depends on your
budget, site conditions and plant material
available. If seeds are to be used, one needs
to understand sustainable harvesting
methods, timing of seed maturation, seed
treatment and germination methodologies
in order to maximise successes. A permit
from Cape Nature is needed to collect seed
and plant material from natural areas.

Timing of planting/sowing is also crucial
and is best done at the beginning of the
rainy season so that the plants have enough
time to establish a good root structure to Wild dagga (Leonotis leonurus) planted on a rehabilitation site on the Breede River near Bainskloof,
survive the dry season. However, if you Wolseley. These plants attract nectar-loving pollinators.
have good irrigation and water supply, this
can be manipulated. IAPs are very good at
colonising disturbed ground, so it is best to
plant and sow indigenous plants as soon as
possible after the IAPs have been removed
in order to minimise the second wave of IAP
infestation and/or secondary invaders from
establishing.
Plant selection is a crucial aspect of riparian
rehabilitation. One should only use local,
indigenous plants that occur naturally in the
same river catchment, in the same riparian
habitat and within the same specific soil type
as on the rehabilitation site. This is necessary
to preserve the genetic integrity of plant
species in the rehabilitation site and within
the river itself. You don’t want to introduce
a plant species that doesn’t naturally occur
in that ecosystem, as it can potentially be
invasive and out-compete the local plants. A
local freshwater ecologist/botanist or riparian
rehabilitation specialist should be able to A rehabilitation site on the Berg River, near Hermon
devise a suitable plant list for you.
Soil additives will also help with the and organisations that are working on
Sourcing of plants establishment of plants in eroded and restoring rivers in South Africa, namely the
It is not easy to find locally sourced plants degraded river systems to boost soil organic Western Cape Department of Environmental
on the market. Most plants produced in carbon. This is especially important if the IAP’s Affairs and Development Planning, WC
commercial nurseries are grown to look great, biomass was removed from the rehabilitation Dept. of Agriculture (LandCare), SANBI, FSC
but may not be adapted to surviving in harsh site (taking its stored carbon with it). Use good – ReforestAction, GreenPOP and Wildlands,
conditions. Many so-called “indigenous” quality organic compost as pathogens and to name a few. There are also global
species are hybrids of natural varieties weeds that survive in second-rate compost organisations like the Society for Ecological
that may in fact pollute the genetics of can become an issue. Inoculated biochar is Restoration (SER) that have devised
subsequent generations and even affect their another alternative that boosts soil health, global standards for restoration and have
wild relatives. It is best to ask a rehabilitation but it is best to inoculate it with local micro- resources to assist people and organisations
specialist where to source the right plants. organisms sourced from pristine habitats as in devising restoration plans. The SER is
close to the rehabilitation site as possible. developing an African Chapter and this
Irrigation is recommended for achieving will hopefully support the UN Decade on
higher success rates for active planting on Fortunately, there is a global drive to restore Restoration.
river banks. In-line drippers are preferable degraded ecosystems, and the UN has
as they are more reliable and don’t require just launched the Decade on Ecosystem Text and photos supplied by Georgina
much maintenance. Irrigation is needed in Restoration 2021-2030, with potential van Biljon. For references, resources and
the first year to help the young plants survive funding and support. There are some rehabilitation nurseries contact her on
over the dry months. subsidised/semi-subsidised programmes georgina@greenintaba.co.za n

16 Landscape SA • Issue 113 2022