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Working in collaboration with the CAO, SANParks and the University of
the Witwatersrand, the CSIR's Earth observations research groups have
achieved several milestones, changing the way large areas like the KNP
and surrounding areas can be managed.
According to Prof Greg Asner, professor at the Department for Global
Ecology at Stanford University and in charge of the CAO, their
relationship with South Africa is quite unique: "It is one of the only
places in the world where we work directly with local scientists on
issues of management conservation. Working in South Africa with the
Kruger National Park and the CSIR gives us the chance to have real
impact," he said during an interview at the time of the CAO's third
mission to the country in April 2012.
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This sentiment is echoed by SANParks' research manager for GIS and
remote sensing, Dr Izak Smit: "We do not have the infrastructure,
technology or expertise to deal with a project of this magnitude. Yet,
working with external partners, we can leverage the expertise and
funding, thereby enriching our work in transforming the science into
management decisions and practices.
"We find ourselves at the interface between the science and the
management of the parks. Collaboration with external partners like the
CSIR, universities and the CAO is essential to the successful management
of the parks, and has had impacts on how we manage the park when it
comes to the provision of water holes and prescribed burning, for
example."
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For Dr Renaud Mathieu, a CSIR principal scientist, the collaboration is
also about building technical skills and capacity in South Africa to
process large sets of data and developing remote sense technologies well
suited to the South African savannah landscape.
"Historically, especially in Africa, most remote sensing-based
approaches focused on tropical deforestation. However, more than half of
the southern African subcontinent is covered with savannah with about
10 to 50% tree cover and undergoing mostly gradual changes such as bush
encroachment or tree logging for fuelwood. Techniques developed for
assessing woody biomass in tropical forests with dense canopies cannot
simply be transferred to savannas and woodlands," he explains.
Futhermore, the long-term vision is to develop the whole LiDAR value
chain, including the local capacity to operationally collect LiDAR data
for environmental management and vegetation applications using local
airborne survey companies. In this regard, the CSIR and SANParks are
already working with a South African company to test the viability, as
SANParks is considering using LiDAR surveys for long-term monitoring.
Research milestone: Sustainability of fuelwood for rural energy needs
The LiDAR data from the 2008 flight campaign have enabled researchers to
map and measure woody biomass in rural areas such as Bushbuckridge,
where harvesting of live wood is still the primary source of fuel for
cooking and heating even when electricity is available.
Researchers combined the LiDAR data with socio-economic data collected
from the area over the past 20 years by the Wits Rural Public Health and
Health Transitions Research Unit, and the WITS programme for Sustaining
Natural Resources in African Ecosystems.
This shows that at the current rate of fuelwood consumption - three to
four tons per year per household - the woodland resources for some rural
villages in Bushbuckridge may only last another 12 years. With the help
of the LiDAR data and fieldwork, researchers have also found evidence
of illegal commercial cutting of fuelwood in the communal rangelands.
"There is great concern that the current levels of utilisation are not
sustainable, with direct negative impacts on the poor, as well as for
biodiversity loss and conservation. Our findings to date regarding the
sustainability of this ecosystem service warrant further investigation,"
says Dr Mathieu.
In all instances, improved estimates will be instrumental to poverty alleviation.
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Research milestones: Loss of big trees in conserved areas
Another significant finding is that large herbivores and fires may have a
bigger impact on the loss of big trees in conserved areas than in
communal areas, where large trees like the Marula are valued for their
fruits. Over five metres high, many of these trees have taken over 50
years to grow.
Dr Mathieu, "We have detected a 20% loss of big trees from research
sites in a private game reserve next to the KNP in just two years,
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compared to a 10% loss of big trees from research sites on communal land
over the same time period."
This was also the first time in his remote sensing career that he found a
100% correlation between prediction of a remote sensing system (the
LiDAR) and ground verification.
But researchers are still puzzled about why and how this is happenin.
"At the moment, we think it is because of different reasons," explains
Dr Mathieu: "In the case of the private game reserve, field work shows
that a combination of elephants and fire damage is involved. For
instance, the elephants push and debark the big trees. The trees are
weakened, and then burn more easily in veld fires."
In the communal areas, trees are cut for building posts for field
fencing and fuel wood; however, it is a big taboo to cut big
fruit-bearing trees like the Marula, and people mostly cut the
lower-growing trees and bushes.
Again, this finding needs to be further investigated and interrogated.
For the remote sensing specialists in South Africa, the recent 2012 CAO
campaign will be useful to confirm or infirm these results over a wider
area and a longer time span.
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