Contents
of June 2003
EDITORIAL
Plant Invaders list
UPFRONT
News
IDENTIFYING INVADERS
Oleander and Tipuana
TREE OF THE ISSUE
Brendan Fox chooses Dombeya
tiliacea
FEATURES
Plastic bags, used tyres and
waste paper recyling
Co-operative conservation initiative
The
Cities for Climate Protection Programme Implemented at Potchefstroom
New council chambers claim
green building status
Asbestos removal in buildings
Environmental award for eco-landscaping
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EDITORIAL
Plant Invaders list
The
landscaping industry, which is in the process of reviewing Table X of the weeds and
invaders regulations and making representations to government to have certain plants
removed from the list, would be well advised to take note of turfgrass supplier Hantie
Cloete’s commendable attitude towards the possible “banning of Kikuyu”,
which has been the main source of his livelihood (see page 13) for many years. Hantie is
fully aware of the invasive nature of Kikuyu and the fact that it is highly water
consumptive and he has actively been looking for alternatives, which is exactly what UGF
has been trying to encourage the landscaping industry to do, particularly through its Tree
of the Issue column which suggests alternative indigenous species.
It is
vitally important that we take great care not to continue to import species that are
liable to become invasive in our country or to export species that may become a menace in
other countries.
It might be
a good idea also for the landscaping industry to look back at the extensive discussion in
the form of ‘Letters to the Editor’ carried in UGF, when the regulations first
came out (UGF Jan/Feb 2001, page 4). This was largely as a result of a letter sent to UGF
by landscape architect Clare Burgess (Nov/Dec 2000). Clare said that she was distressed to
see trees such as Tecoma stans (Yellow Bells), amongst a number of others, on the list.
She indicated that this species might well be a problem in other parts of SA but was
certainly highly valued as a shade tree on the Cape Flats.
The problem
with plants such as the latter is that if they are allowed to be grown in certain areas
where they may not as yet have shown invasive tendencies, they can easily be transported
to other areas in the country where they are already manifesting as serious problems.
Hildegard Klein of the Plant Protection Research Institute pointed out that plants that
have become invasive in other countries needed to be carefully watched – adding that
Tecoma stans (UGF Jan/Feb 2003, page 7) was also a declared weed in the USA.
Another
aspect of invasiveness is exemplified in an interesting article sent through by Kay
Mont¬gomery, who has been managing the programme to create awareness about invaders in
the nursery industry. The article serves to illustrate the frightening ability of a plant
to become invasive almost over night. Here is a paraphrased section of the article from
the Science News website (www.sciencenews.org/20030412/bob9.asp) entitled: ‘Is your yard a menace to parks and
wildlands?’.
Janet Raloff
bought a home in Washington DC and shortly thereafter installed 35 Liriope muscari plants
in her garden. “Gardening books recommend these East Asian, shade-tolerant border
plants because they ‘don’t creep’ – that is, invade surrounding areas.
And for 15 years those plants maintained a neat border. Four years ago, something changed.
A few clumps of two or three spindly liriope leaves sprouted in the lawn. By last summer,
hundreds of clumps were infesting the property – in some cases up to 50 feet away
from the liriope border.”
Miami
horticulturist Mike Maunder says this is a classic example of invasive ecology. “Many
species will sit absolutely blameless for decades – and then, ping! they explode all
over the place.” As big a nuisance as such episodes pose to gardeners, they risk
becoming an ecological nightmare if the botanical invasion jumps the garden fence into
parks, forests and wildlands. In many cases, such as with liriope, scientists don’t
understand why such invasiveness develops. However, the more domineering of these plants
almost invariably have foreign origins, notes Maunder, who has studied such botanical
thugs the world over. There are an increasing number of formerly mild-mannered guests that
have morphed into bullying weeds, he says.
Copies of
the Jul/Aug issue of UGF will be available at Brooke Pattrick’s stand at the
Afriwater/Afribuild show in August this year and the issue will contain largely water and
building related articles. The exhibition is being held at the Sandton Convention Centre
from 13-15 August 2003
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UPFRONT
Undescribed plant species interrupts plans for new open pit
Potgietersrus
(PPRust) platinum mine, north-west of Mokopane (previously Potgietersrus), was planning to
expand its current operations in the Sandsloot open pit. As a requirement for the
expansion, an addendum to the existing Environmental Management Programme Report (EMPR)
was required and in April 2002 SRK’s environmental department was commissioned to
prepare the addendum for the new Zwartfontein South open pit, along with the PPRust north
operation.
One of the
specialist studies required for the EMPR addendum was a botanical survey and this was
carried out by taxonomist Pieter Winter, curator of the Herbarium at the University of the
North. During the survey, he discovered an undescribed species of Corchorus in the
northern section of the proposed pit. In line with IUCN Red Data listings, the plant was
considered likely to be ‘critically endangered’ because of the small number of
plants discovered by Winter. There was a possibility that if mining were to go ahead the
plant would be threatened with extinction. The mine responded to SRK’s
recommendations with alacrity, bringing its plans for the new open pit to a halt and
immediately fencing off an area of 3 ha to protect the population of Corchorus.
According to
Winter, the plant which is in the process of being described, Corchorus micranthus in ed,
is an annual which colonises newly disturbed soil – a pioneer of hostile disturbed
environments on heavy clay soils. It is able to survive in seed form for many years until
disturbance occurs. Ross Liston of SRK said that it made sense to assume that the
prostrate plant was a pioneer as the initial population of the plant had been discovered
in the vicinity of historical mine workings from the turn of the century – an area of
disturbed soils.
PPRust,
under the guidance of SRK, commissioned Winter to begin searching for other populations of
the seemingly threatened plant, immediately. The decision was made to begin mining at the
southern end of the proposed pit to allow time for a solution to be found to the
management of the Corchorus population. The initial botanical survey had been undertaken
in late autumn and the need to allow time for a summer survey was taken into account.
There is a need, according to IUCN, for 10 stable populations or 10 000 individual plants
to be in existence before a species can be considered to be not vulnerable.
Winter,
backed by PPRust, carried out a far-reaching search which extended into neighbouring
pro¬vinces. He found indications in the herbarium that material of what was possibly the
same species had been collected at Newcastle and by January 2003 populations had been
discovered at Newcastle, Barberton, Brits and Bothasvley. Simul¬ta-neously, the mine
commissioned two members of surrounding local communities – Calvin Siburi and Piet
Makletji – who were trained to search for the plant on mine property and by February
2003 over 10 000 individual plants had been discovered in the vicinity and further afield.
It had
become evident that the mining posed no threat to the species and the species could be
downgraded according to IUCN guidelines, as it was clearly not vulnerable. Duncan Stevens
of SRK said that the initial population would be carefully removed from the area scheduled
for mining along with its seedbank and kept in a holding nursery, so that the material
could be used for rehabilitation purposes at a later stage – as a pioneer that is the
role that it would play naturally. PPRust has formed a small black empowerment venture
called Cochorus Environmental Services that will undertake small rehabilitation projects,
along with eradication of invasive vegetation and waste management.
Stevens
ascribed the success of the process to excellent firsthand communication between a set of
unique, knowledgeable people who trusted each other. He mentioned the vital role played by
Frank Pieterse, the environmental man¬ager at PPRust, and explained how receptive the
mine manager, Dean Pelser, had been to the recommendations. He said that regular liaison
with the mine designers, Gemcom, had meant that they were constantly kept abreast of
developments and were as a result extremely co-operative.
“Although
it was quite frenetic initially, everything seemed to come together and all the necessary
parties got involved. Everyone was very aware of the fact that they could have caused an
extinction, when the initial discovery seemed to be the only population, and the mine
essentially funded the research into this undescribed species,” concluded Stevens.
Security access
restrictions
The City of
Johannesburg has been involved in an interactive process with all its stakeholders over
the past 12 months to formulate a security access restrictions policy. The terms of
reference for the panel were to co-ordinate and oversee the public participation process
and ensure transparency and debate and the careful evaluation of comments and
representations, and finally to compile a report and make recommendations.
The issues
that were considered in the process were safety and security; impact on property values;
impact on traffic and circulation; community cohesion and conflict; constitutional and
legal issues; urban functionality issues; impact on service provision; social and economic
issues.
After
careful consideration and evaluation of all these complex issues, the panel concluded that
the long-term impact of security access restrictions was not desirable and therefore road
closures should not be promoted in the City of Johannesburg.
It is,
however, important to note that the panel indicated that given the legal imperatives, it
would be necessary for the City to consider putting in place a process to consider
applications for security access restrictions. The City has gone beyond the recommendation
of the panel by acknowledging that issues of safety and security need to be carefully
considered.
Each
application will therefore be considered on its own merits. Specific criteria have been
set down to ensure that all impacts of security access restrictions are carefully
considered to ensure urban functionality and that the provisions of the Constitution are
not compromised.
The
Johannesburg Roads Agency, as Johannesburg Council’s implementing agent, will manage,
administer and evaluate the applications in accordance with policy. Once the proposed
closure is evaluated, a recommendation will be made to the executive director: Development
Planning, Transport and Environment. An appropriate appeal mechanism will be developed to
afford applicants an opportunity for review.
Currently,
there are over 300 applications in the system awaiting evaluation and decision. These will
be assessed in terms of the Security Access Restriction Policy for the City of
Johannesburg. All existing road closures are illegal as the approval time for those that
were legal has lapsed. The necessary action will be taken to address the issue of illegal
closures and possible removal at a cost to those who installed the closure.
Given that
the climate in the city is affected by ongoing efforts on the part of all stakeholders to
deal with the challenges of combatting crime, the city will review its policy and the
impact of this activity from time to time to ensure responsiveness to conditions on the
ground.
For further
information contact Kgotso Chikane, spokesperson for the Executive Mayor. Tel: (011) 407
7558. Cell: 082 464 9446. Email: kgotsoc@joburg.org.za
Indegenous Plant
Growers Association
Talking
about the newly formed Indigenous Plant Growers Association, committee member Charles
Craib gave reasons for the formation of the group: “As growers of indigenous plants
we have become progressively more and more isolated from government – more sidelined
as users and developers of the floral diversity of our country. We have encountered
excessive problems in dealing with basic matters, such as permits, access to seed
resources and getting answers to letters sent to provincial environmental departments
– this apparently happens across all provinces.”
According to
Craib, the Association is a group of concerned people – affected parties – who
have perennially had negative experiences in dealing with nature conservation authorities
and who have decided to form a meaningful Association. A steering committee has been
nominated to identify all the problem areas and prepare the way for the formation of a
strong national body. One of the biggest concerns is the proposed Biodiversity Bill which
may well impact negatively on users of indigenous plants. Numerous discussions have been
held and the constitution is at draft stage.
It is
intended that a national founding meeting will be held as soon as the constitution has
been finalised. There are already numbers of growers countrywide who have joined and are
paying an incorporation fee to fund the setting up of the Association. It is vitally
important that indigenous plant growers band together to negotiate effectively with
government.
The primary
objectives of the Association are:
•
to seek and share
information about Indigenous Flora in the broadest sense but particularly concerning its
propagation and cultivation;
•
to deal with the
issues related to the marketing of Indigenous Flora
•
to address issues
relating to the export of Indigenous Flora;
•
to make a contribution
to the sustainable use and conservation of Indigenous Flora;
•
to liaise with
government to work out systems which will facilitate the sustainable use and promotion of
Indigenous Flora;
•
to involve the
broadest community in South Africa with the propagation of Indigenous Flora; and
•
to inform and educate
the public about issues pertaining to the use
of Indigenous Flora.
The interim
committee of the Indigenous Plant Growers Association comprises six members with Dirk
Neiteler of Sunkloof Nursery in the chair, Linda De Luca of Random Harvest responsible for
canvassing members, landscape architect Erika van den Berg representing the landscaping
industry, Charles Craib drawing up the constitution, horticulturist Karen Hendry serving
as secretary and Louis Meintjies of Bergsig Nursery.
Contact Linda De Luca. Tel: (011) 957 2758. Cell: 082 553 0598. Email: ipga@icon.co.za
Fynbos Forum
This year’s
Fynbos Forum will be held at Hartenbos Resort, Hartenbos, Mossel Bay from 5-8 August.
Session themes will include: CAPE, partnerships, Renosterveld, ecology and systematics,
aquatic ecosystems, policy and legislation, utilisation, education, landuse planning and
decisions.
The Fynbos
Forum is an affiliation of researchers, planners, managers, landowners and a range of
other stakeholders that meets annually to discuss management issues and research results
and to formulate priorities for future research and conservation management actions
required to ensure the conservation and sustainability of Fynbos ecosystems. In order to
achieve this goal the forum undertakes to assess biological resources, ensure
institutional capacity and consider socio-economic issues.
Contact Wendy Paisley, Fynbos Forum Co-ordinator. Tel: (021) 797 2284. Email:
paisley@nbict.nbi.ac.za
Ecocircles
Mahesh
Roopa, acting director of Health and Environmental Services at Potchefstroom City Council
described the city’s ‘Ecocircles’ project – a project which allows 4
200 homes to harvest their own fresh vegetables. The scheme is run by an NGO, the EcoGrow
Project, in conjunction with the municipality. Fifty-six members of EcoGrow visit the
individual homes of impoverished families in the Potchefstroom area to help organise their
so called Ecocircles – an idea which, Roopa explained, originated in China.
Vegetable
seedlings from the municipal nursery are grown on to a certain stage and then planted out
at selected homes. The centre circle on the site usually comprises a fruit tree and this
is surrounded by six circles for different vegetables, such as spinach, carrots, tomatoes,
onions, cabbage and strawberries.
An
innovative irrigation system around each circle comprises a ‘Wetpipe’ which is a
hose or piece of piping that is made out of waste materials, such as old tyres and plastic
bags, and is porous. Ideally, the pipe should be buried just under the soil at root level.
The water oozing from the pipe will then not evaporate or cause erosion.
Roopa
commented that these Ecocircles with their circular Wetpipes have turned many a wasteland
area into a green garden. With the buried Wetpipe it is only necessary to water once a
week in summer and twice a week in winter. Extra municipal water is supplied to households
with Ecocircles.
Another NGO
comprising a group of elderly women cooks food for the EcoGrow volunteers on a daily basis
and they are paid by the municipality for the preparation of this food. Roopa said that
the project had been taken to several neighbouring towns including Ventersdorp,
Klerksdorp, Orkney and Makwasi Hills. He commented that the provincial government was
backing the project, which had been in existence in Potchefstroom for two years.
Contact Mahesh Roopa at Potchefstroom Municipality. Tel: (018) 299 5257 Email:
mroopa@nwpg.org.za
GEF promotes
sustainable transportation
The
governing council of the Global Environment Facility (GEF) has approved US$15,61 million
in grants for two projects that will involve residents of Santiago, Chile and Lima, Peru
in promoting a shift to less polluting forms of ground transportation.
GEF will
contribute $8, 28 million to the $134 million ‘Lima Urban Transport’ project.
Project co-financing comes from the Peruvian government ($46 million), the World Bank ($40
million) and IDB ($40 million).
The
population of Lima is expected to approach eight million by 2004 and the need for a better
public transport system is becoming more urgent. The city’s roads are congested and
dangerous, especially for pedestrians. The city’s bus fleet is the oldest in Latin
America, with an average vehicle age of 16 years, and is not subject to minimum emission
and noise quality standards. Urban transport improvements and reforms will enhance the
economic competitiveness of Peru while improving the quality of life for local residents,
in particular low-income groups in outlying municipalities who need better public
transportation so they can access job opportunities.
The project
aims to reduce the emission of greenhouse gases from Lima’s transport network by
improving the availability and efficiency of public transportation. Segregated busways
will be created so bus travel times can be reduced. Bicycle usage will be promoted by
creating bike routes to connect poor neighborhoods with bus terminals, and by improving
the safety and condition of existing bikeways with assistance from local residents.
The second
project, ‘Sustainable Transport and Air Quality for Santiago’, will be funded by
a $7,33 million GEF grant and $7,44 million in co-financing from the Chilean government
and the private sector.
The project
will employ several strategies to promote bicycle usage in Santiago, including
collaborating with local citizen’s groups to develop grassroots support for bicycle
usage, launching a publicity campaign to develop an attractive image of the bicycle as a
transport mode, conducting safety campaigns directed at drivers and cyclists, and
encouraging major employers to provide shower and bike parking facilities for employees
who commute by bicycle.
In addition,
the project will promote land-use policies so that the average length and number of
private car trips can be reduced; such as traffic calming measures in the historic center
of Santiago; the social, environmental, and economic impacts of road pricing (charging
tolls) are studied; financial and regulatory barriers to introducing clean technologies
for transport are removed; and improved air quality is taken into consideration, in spite
of economic and demographic growth.
Website: www.theGEF.org
Landscape
architect Peter Walker awarded Honorary Doctorate
The
Department of Architecture at the University of Pretoria has awarded an Honorary Doctorate
to world renowned landscape architect Peter Walker. This is the first Honorary Doctorate
in landscape architecture to be awarded on the African continent.
Peter Walker
is an accomplished landscape architect, teacher, mentor, historian, artist, sculptor,
writer and publisher – and an inspiring man of ideas. The programme in landscape
architecture at the University of Pretoria has been in existence for 30 years and it is to
celebrate this landmark and strengthen the international profile of the course, that the
award has been made to Peter Walker. His recognition around the world is unquestioned.
His approach
to his work in later years has been influenced by minimalism, where he saw possibilities
of expressing its essence in the landscape. Renowned Japanese architect Yoshio Taniguchi
said of him: “…Walker uses nature as an abstract object. His ability to combine
this abstraction of nature and an insightful response to the condition of the site has
resulted in sublime works of landscape architecture that may be properly thought of as
residing in the realm of art”.
He has
worked on projects in many different countries – amongst which are the Sony Centre in
Berlin, Millennium Park for the 2000 Sydney Olympics, the headquarters of Novartis
Pharmaceuticals in Switzerland and numerous projects in the USA and Japan. He has
collaborated with architects of the stature of Sir Norman Foster, Helmut Jahn, Yoshio
Taniguchi and Ricardo Legorreta.
He held a
variety of posts at the Graduate School of Design at Harvard from 1977 to 1992 and most
recently was Head of the Department of Landscape Architecture at the University of
California (1997-99).
Walker
claims that the field of landscape architecture should be recognised as an independent
entity with a place and status equivalent to that of the other visual arts and
architecture. He believes that environments should be created that are: “... serene
and uncluttered, yet still expressive and meaningful. More than ever we need to
incorporate in our built environment places for gathering, congregation and efficiency
along with spaces for discovery, repose and privacy in our increasingly bewildering,
spiritually impoverished, overstuffed and undermaintained garden, Earth.”
Kikuyu under the
spotlight
At Evergreen
Garden’s Open Day in late April this year, Hantie Cloete took a pro-active stance
towards the possibility that within the next couple of years Kikuyu will be added to the
list of declared weeds and plant invaders in South Africa. He said that it was a waste of
time kicking out against this strong possibility and that instead he saw this as a
challenge – an opportunity to bring new turfgrass varieties onto the market. Cloete
is very aware of the environmental problems caused by the invasiveness of Kikuyu.
He indicated
that he thought it likely that by 2004 Kikuyu would be banned in open areas and on
pavements. Because it is proposed as a category 2 invader, it may be allowed in demarcated
areas such as on sportsfields and in gardens, where it will have to be kept under control.
He said that Evergreen Gardens had actively been looking for alternatives.
Evergreen
Gardens has 240 ha under instant turf – and this is largely Kikuyu lawn (Pennisetum
clandestinum). Kikuyu has been on Table X for the last three years since the amended
regulations on weeds and invader plants were brought out by the National Department of
Agriculture. Table X comprises proposed weeds and invader plants and this list is now up
for review. Kweek or Bermuda grass (Cynodon dactylon), although it is indigenous, is on
the same list.
The Open Day
served to introduce a new turfgrass variety, Palmetto (St Augustine), as Evergreen’s
latest addition to its instant lawn varieties and Cloete pointed out that it was cold and
frost tolerant and could take more shade than Kikuyu. He said that Evergreen Gardens had
trialled it over the past four years and that it was less invasive than Kikuyu and
required less water.
“Our
relationship with turf producers in the USA has meant that we have been exposed to over
400 different turfgrass varieties. We will bring in the ones that are best suited to our
conditions in South Africa,” commented Cloete.
Environmental benefits of
turfgrass
At the Open Day, Susan Allen of Sakata Mayford made mention of the many
environmental benefits of turfgrass which need to be taken into account alongside its
recreational and aesthetic benefits. Turfgrass Producers International have put out a
booklet in the USA that details these benefits, including a statement from the US Congress
which says: “Turfgrass sod in urban areas can aid in the reduction of CO2 emissions,
mitigating the heat island effect, reducing energy consumption and contributing to efforts
to reduce global warming trends”.
Scientific
research in the US has documented the many benefits of turfgrass to the environment. The
following are some of these:
•
it acts as a soakaway
recharging the groundwater supply;
•
it acts as a natural
filter, reducing the many pollutants carried by runoff in urban areas;
•
lawn traps and removes
dust from the air;
•
turfgrass is a
cost-effective method of controlling wind and water erosion;
•
250m2 of
lawn releases enough oxygen for a family of four to breathe and absorbs CO2
from the atmosphere;
•
turfgrass has an
extensive cooling effect;
•
on a hot summer’s
day lawns will be 10°C cooler than asphalt and ±5°C cooler than bare soil;
•
watered only when the
grass plants need it (with an efficient irrigation
system), turfgrass will very efficiently and effectively utilise almost every drop; and
•
well maintained lawns
provide an effective fire-control buffer.
Contact Evergreen Gardens. Tel: 948 9728. Email: greensod@global.co.za
GEF funding to
protect the Biodiversity of the Cape Floristic Region
The
governing council of the Global Environment Facility (GEF) has approved US$14,55 in grants
for two projects that will help protect the rich biological heritage of South Africa’s
Cape Floristic Region, which harbours more than 9 000 plant species, 70% of which are
endemic to the region – that is found nowhere else in the world.
The two
projects are part of the innovative 20-year programme ‘Cape Action for People and the
Environment’ (CAPE) (see UGF Nov/Dec 2002). The programme addresses all aspects of
this highly vulnerable region, including freshwater, terrestrial, estuarine and marine
life. This new strategy will have a major impact on conservation, land-use planning,
environmental management and nature-based tourism in the Western and Eastern Cape.
The CAPE
programme is in three phases, the first of which, the ‘South Africa CAPE Biodiversity
and Sustainable Development’ project, will be funded by an $11,3 million GEF grant,
$26,93 million in co-financing from the South African government and $17,2 million in
co-financing from the private sector. The World Bank and the United Nations Development
Programme will implement the project in partnership with South Africa’s National
Botanical Institute.
Project
goals include the addition of more than 4000 km2 of land (including three terrestrial
areas, two marine areas, two estuaries and two freshwater systems) to existing protected
areas; planning and development in at least five priority areas that adequately addresses
biodiversity concerns; and the adoption of environmentally sound practices by agricultural
and tourism businesses.
An
information management system will be created to enhance inter-agency cooperation and
bioregional planning.
The GEF
Council has also approved a grant of $3,2 million for another project that will support
the CAPE programme, the ‘South Africa Agulhas Biodiversity Initiative’. This
project will protect one of the world’s largest storehouses of species that are
vitally important to South Africa and the world-wide community. Lowland fynbos, for
example, yields a wealth of cut flowers and garden plants and is more botanically diverse
than the richest tropical rainforest. Renosterveld contains an amazingly diverse number of
bulb species that are valued around the world for their showy, best-selling flowers. The
Agulhas area is currently being threatened by a range of human-induced pressures but
nevertheless constitutes one of the best remaining opportunities for in situ conservation
of the Cape Floral Region’s lowland habitats.
The Agulhas
Biodiversity Initiative will be implemented by the United Nations Development Programme in
partnership with South African National Parks (SAN Parks). In addition to the GEF grant,
the project will be supplemented with co-financing from the South African government
($6,78 million), the private sector ($408 500) and other international institutions ($1,31
million). An innovative mosaic of protected areas on public and private lands, with
productive landscapes on neighbouring farmsteads, will be developed.
Other
project goals include demonstrating ecologically, socially, and ethically sustainable ways
of harvesting wild fynbos; engaging local communities in implementing an ecologically
responsible tourism strategy that contributes to sustainable livelihoods; and increasing
local support for biodiversity conservation.
Website: www.theGEF.org
HIV sufferers
receive training in permaculture
The Urban
Greening Fund, through Food & Trees for Africa (FTFA) and DWAF, sponsors the Aganang
Community Development Centre (ACODC), a community-based organisation involved in
permaculture food gardens at Mathibestad Clinic in the North West. The project members
also provide HIV/AIDS counselling, facilitating HIV/AIDS workshops and home based care,
and they receive further support from the Department of Health.
The project
members, community and local schools in Mathibestad have recently celebrated the launch of
the Aganang permaculture project. The permaculture training was provided by FTFA’s
project officer Joe Matimba whose post is funded by The Green Trust. As a result of this
training, ACODC is now donating organic vegetables to orphans and the gardens are used for
training school children and community members, as well as the HIV infected and affected
people, on how to produce food for themselves by utilising available resources. The
committed project members have further contributed to the greening of schools and 350
trees have been planted in different schools in the area.
Sello
Masingi, the ACDOC project coordinator, said of the results, “This permaculture
project has helped us to donate vegetables to HIV/AIDS, TB and asthmatic patients. The
garden products are also generating money for us. Patients have been coming to the project
for training and to purchase fresh vegetables.”
The Urban
Greening Fund is a national, local government, NGO and civil society partnership for
sustainable development. It was established by DWAF and FTFA in 2000 to facilitate the
increasing number of CBO and grassroots NGO sustainable greening initiatives. This
partnership has supported several greening and food security projects and is seeking
further funding to respond to the over 170 applications it currently has on file.
Contact Joe Matimba Tel: (011) 803 9750.
Go Green Go
Willard campaign
Earlier this
year, Food & Trees for Africa (FTFA), Willard Batteries and Johannesburg City Parks
planted 500 trees in the suburb of River Park to contribute to the Greening of Alex
campaign. The Go Green Go Willard campaign promotes the recycling of car batteries and is
aimed at communicating Willard and FTFA’s shared values in respect of relevant
environmental issues. Autotech is contributing funds to FTFA which are dependent on the
success of scrap battery recovery.
FTFA has
been working in Alexandra for many years and has joined the presidential Alex Renewal
Project with the aim of helping to green Alex, one of South Africa’s oldest
townships. The Greening of Alex is improving civic pride and contributing to a spirit of
community, along with improved property values, cleaner air, less noise and generally
improved aesthetics.
For more
information contact Jeunesse Park (011) 784
6399.
Email: jpark@trees.org.za
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IDENTIFYING INVADERS
Oleander and Tipuana
UGF’s
regular column to help with the identification of invasive species that are listed in the
amended regulations of the Conservation of Agricultural Resources Act.
Nerium
oleander
Nerium
oleander – commonly called Oleander – is a declared weed, category 1, that needs
to be eradicated because it is prohibited on any land surface in SA. The sterile
double-flowered cultivars are not invasive. All parts of the plant are extremely poisonous
and intake may be lethal. It is a woody evergreen shrub which grows up to 6m in height.
Seriously invasive forms usually have pink, slightly scented flowers with a single row of
petals. When the long, narrow seed capsules burst open they release numerous small seeds
tufted with hairs. It is an ornamental or screening plant which has unfortunately been
used prolifically on road islands to screen the two sides of dual carriageways from each
other. It originates in the Mediterranean. It invaders watercourses, particularly rocky
watercourses in semi-arid mountain valleys. It is more problematic in the Western Cape
than elsewhere. It needs to be dug out be hand (carefully, because it is a skin irritant)
as there is no registered herbicide or biological control.
Tipuana tipu
Tipuana tipu – the Tipu Tree or Tipuana – is a declared invader,
category 3. It is a large spreading deciduous tree, up to 23m in height. It bears yellow
flowers over the spring and summer months and its winged pods are large and distinctive.
It originates from South America where it occurs naturally in Brazil, Bolivia and
Argentina. It is cultivated largely for ornamental and shade purposes. It invades
roadsides, river banks and urban open space and is problematic in Gauteng, Limpopo,
Mpumlanga and KZN. It needs to be removed mechanically. Because it is a category 3
invader, it may not be propagated, sold or planted but if it was already in existence in a
garden, street or urban park at the time the amended regulations came into being, it need
not be eradicated, as yet.
Most of the
information in this column is taken from Lesley Henderson’s book ‘Alien Weeds
and Invasive Plants’. Contact the National Department of Agriculture for further
information:
Email:
declaredweedsandinvaders@nda.agric.za or
Working for Water’s Weedbuster
Hotline: 0800 005 376.
-----
TREE OF THE ISSUE
Brendan Fox chooses Dombeya tiliacea
Forest
Wild Pear
This lesser
known Dombeya which is under-utilised in landscaping is the choice of Brendan Fox of
Emerald Landscapes in Hillcrest, KwaZulu-Natal. It grows in forest, on forest margins and
on rocky hillsides – Brendan has seen it in the bushveld of the Tugela river valley
– along the eastern coast of South Africa. It is a small to medium-sized deciduous
tree which is often multi-stemmed.
Brendan
planted the tree, which he bought it from Silver Glen nursery, in his own garden in
Hillcrest about 4-5 years ago at the height of about half a metre, and it now stands at
4-5m in height and the same in width, meaning that it is fast growing. It is planted on a
north facing slope in his garden which is 20km inland from the coast and it gets sun all
day long. His is a multi-stemmed specimen and he has never pruned it.
He calls it
a striking tree which flowers prolifically in autumn for a period of 4-6 weeks. He also
likes the look of the combination of older flowers which turn a rust-brown colour along
with the younger white flowers which hang in clusters and are faintly sweetly-scented. The
rust coloured flowers stay on the tree for a long time. He comments that the tree is
drought tolerant and an exceptional insect plant, which he says is covered in bee and
other insect species particularly during flowering and attracts a variety of insect eating
birds. He says that Emerald Landscapes is planning to grow the tree in its nursery.
There are a
number of similarities between this tree, Dombeya tiliacea and the Natal Wild Pear,
Dombeya cymosa which has virtually the same distribution range in the wild and flowers at
more or less the same time. The Natal Wild Pear has much smaller flowers with fewer
flowers per cluster and smaller leaves, al¬though the leaves are a similar heart-shape.
The bark of D. tiliacea is darker.
Andrew
Hankey of the Witwatersrand National Botanical Garden is of the opinion that both these
species deserve more utilisation in gardens. Hankey has planted a very attractive small
grove of multi-stemmed D. cymosa around a bench in the Garden. A larger specimen in the
Garden which maintains its dry brown flower clusters until early spring manifests
attractive reds and purples in its dying leaves over autumn and winter.
-----
FEATURES
Plastic bags, used tyres and
waste paper recycling
The
agreement signed in September last year banning the use of thin plastic bags in favour of
thicker recyclable bags came into effect on 9 May this year. It is hoped that the
implementation of the new plastic bag regulations will lead to lowered food prices because
the retailer will no longer factor the price of the old thin plastic bag into the cost of
items but will charge directly for the thicker (30 micron) bags. The new regulations will
encourage re-use, reduction and recycling of plastic carrier bags. Customers are able to
re-use the thicker, much stronger bags or have the option of bringing their own carrier
bags to the retail store.
A non-profit
Section 21 company is being set up to promote efficiency in the use, re-use, collection,
recycling and disposal of plastic bags; to investigate and make recommendations to
government in respect of the development of new markets for recycled material; and to
manage and support government in the removal of plastic bag litter from environmentally
sensitive areas. The promotion of recycling will create jobs for the countries unemployed.
Manufacturers and importers of plastic shopping bags will pay a levy towards the
operations of this company.
“The
regulations have for the first time put real value to plastic bags,” commented Valli
Moosa, Minister of Environmental Affairs and Tourism. “They will ensure a dramatic
strengthening of the recycling industry, the creation of much needed jobs for the
unemployed and the retention of current jobs in the plastics industry – and will
safeguard the environment.”
Moosa has
expressed his gratitude to both retailers and customers, saying that the rapidity with
which the regulations have been supported has been beyond expectations. He adds that the
Department intends engaging with retailers who are not complying to determine and solve
their problems. “We don’t want to do this as a bureaucratic process, a ‘cold
law’ from government, but rather as a process that is focussed on public awareness.
The watchdog
newsletter Green & Gold that has as its motto ‘the responsible choice for
business and industrial leaders’, is not happy about the ban. It maintains that the
problem with a government ban is that a ban is not a natural part of an economic system.
An article entitled: ‘What will they really bag?’ says that the results of the
ban on thin plastic bags will probably be a number of other actions and functions that are
not visible immediately.
“For
example, we know that many people use the now banned thin plastic bags to line household
rubbish bins. They would then just lift the full bag out of the bin, tie it closed and
throw it into the main refuse bin. Now with no thin plastic bags, what will housewives do?
We don’t know, but alternative behaviours will develop – maybe they will wash
the bins much more often with detergent, so maybe more detergent goes down the drain,
maybe more plastic detergent bottles will be discarded. Maybe the housewives will line
bins with old newspapers (instead of sending the newspaper for recycling), causing more
sheets of newsprint to go into the waste system. Who knows?”
With
consumers now having the option of bringing their own packaging to retail shops and of
re-using the thicker bags that they have bought at check-out points in other shops, Green
& Gold maintains that shops will have difficulty in combatting shoplifting. They will
no longer be able to make shoppers leave their own bags at a check-in counter. The thin
walled bags of the past served as a kind of receipt for goods bought.
If you are
looking for negatives, they can always be found. Urban Green File feels that the concerns
of Green & Gold will be addressed with time: that the ban on thin plastic bags will
help considerably towards alleviating the litter problem in the country in the long run,
will mean that less non-biodegradable plastic will go to landfill and that the general
public will learn, very quickly, to treat plastic bags with respect and not as ‘throw
outs’, as a clear value has now been placed on them.
Hotline on plastic bag regulations: 0800 203 622
BP provides free brown
paper bags
BP is providing free brown paper carriers to customers at its 200 BP Express
stores throughout South Africa. Vusi Cwane, general manager of BP’s retail marketing
division, said the company had decided to provide free paper bags as part of its
commitment to the environment.
Australia
debates options for tyre disposal
Technological
advances have prolonged the lifespan of the motor vehicle tyre, but Australians still
generate more than 18 million waste tyres each year. Seventy percent of these are known to
be disposed of through landfill or illegal dumping – harming the environment and
resulting in lost opportunities to recover valuable material and energy that can be used
in other products.
Three main
policy options for a national waste tyre management scheme were debated at a meeting of
the Environment Protection and Heritage Council at the end of last year: a take-back
approach, a levy benefit scheme or a tradeable certificates system.
Under the
take-back approach, manufacturers or importers (or a dedicated producer responsible
organisation) would take back worn tyres from producers for recycling. The levy benefit
scheme involves imposing a levy or advance disposal fee on manufacturers and tyre
importers. The fees collected would then be used to fund programmes targeted at
end-of-life issues, including benefits paid to recyclers or re-users for waste tyres or to
fund programmes dealing with education, re¬search, development and marketing.
Under the
tradeable certificates system, certificates would be issued to recyclers who undertake
waste tyre recycling and re-use activities, and manufacturers and tyre importers would
puchase certificates from these recyclers and would be required to hold certificates
proportional to the volume of new tyres sold.
Tyre
recyling activities include using tyres as a fuel substitute for high energy industrial
facilities such as cement kilns, use in rubber-based products, and crumbling for use in
roadbase resurfacing, paving products, adhesives and as loose fill for soft fall areas.
In a public
consultation period earlier this year, the Australian public commented on preferred policy
options.
News item
from the newsletter for Autralia’s Environment Protection Divisions entitled: ‘Environment
Australia’. For more information access website:
www.ea.gov.au/industry/waste/awr/tyres.html
Waste paper recycling
assists hospice and SPCA
Householders in many suburbs in Gauteng and in Durban, Pinetown and the South
Coast, have been given an opportunity to assist two key community care service
organisations – Hospice and the SPCA – simply by putting out their old
newspapers, magazines and cardboard every fortnight for collection by Mondi Recycling’s
Kerbside Paper Pick-Up team.
Kerbside
Paper Pick-Up has promised to donate R30 to both Hospice Wits and SPCA in these areas for
every tonne of waste paper collected as a result of any additional support given to the
existing collection programme by residents.
The average
monthly tonnage of waste paper collected in this way countrywide is 600 tonnes, which
means that only six homes out of every 100 in the areas where Kerbside Paper Pick-Up
operates have been putting out their waste paper for collection.
“If
just six more homes in every 100 participate, the national monthly total collected for
recycling can be doubled to 1 200 tonnes,” says Mondi Recycling’s national sales
and marketing manager Peter Hunter. “At the same time it will give Hospice and SPCA a
significant income boost to help them continue the good work that they do.”
All that
residents in the areas in which Kerbside Paper Pick-Up operates are being asked to do is
to place their old newspapers, magazines and cardboard into a Ronnie Bag and place it
outside their gates before 8:00hrs on their collection day.
Hunter says
there are huge benefits to be gained from recycling waste paper (magazines, newspapers,
scrap paper and cardboard). “For every tonne collected and recycled, 17 pine trees
are saved, helping to preserve existing forest resources, and three cubic metres of
valuable landfill/municipal dump space is kept free – saving municipal costs and
benefiting ratepayers. We also use 40% less energy in manufacturing new paper by using
recyclable waste paper and this has a significant downstream effect in reducing
atmospheric pollution and, last but not least, recycling keeps suburbs cleaner by reducing
litter.”
Hunter adds
that recycling waste paper also creates considerable opportunities for small businesses
and entrepreneurs as well as many thousands of jobs in both the formal and informal
sectors.
Contact Kerbside Paper Pick-Up on the toll-free line 08000 22112 Website:
www.paperpickup.co.za
Europe’s waste
problems
In a report put out by the European Environment Agency (EEA) press office
earlier this year, the belief was expressed that many of the problem’s linked to
Europe’s growing waste volumes could be solved if countries learnt from other
countries that have pioneered solutions – where one country is behind on a particular
aspect, another is ahead. The challenge for countries in the coming years will be to
utilise each other’s experiences rather than to find new solutions. The report does
caution, however, that not all initiatives can easily be transferred from one country to
another.
The EEA is
the main source of information used by the European Union and its member States in
developing environment policies. The Agency aims to support sustainable development and to
help achieve significant and measurable improvement in Europe’s environment through
the provision of timely, targeted, relevant and reliable information to policy-making
agents and the public.
The report
focusses on ten case studies of some of the most significant initiatives undertaken in
Europe during the 1990s to promote and encourage waste minimisation. The studies are drawn
from eight countries and cover five themes: producer responsibility, voluntary agreements,
legislative requirements, information programmes and waste taxes.
The report
draws several general conclusions:
*
Waste quantities are
continuously increasing; two-thirds of the waste is landfilled, whereas waste recycling
rates have shown a rather limited increase over recent years.
*
Solutions encouraging
separation at source, reducing landfilling, increasing recycling and waste prevention have
been developed by many EEA countries.
*
Several cases of waste
prevention have been successful but are still only applicable at the local level.
*
Most of the case
studies show promising results and may serve as inspiration for future initiatives.
The report is available on the EEA website: http://reports.eea.eu.int/topic_report_2002_2
-----
Co-operative conservation initiative
Carol Knoll
spoke to Andrew Hankey, specialist horticulturist at the Witwatersrand National Botanical
Garden, about the Garden’s threatened plant programme, several initiatives of which
are being carried out in conjunction with nature conservation authorities. Hankey
explained that the Garden had taken over the ex situ element of the conservation of four
threatened succulent species: Orbea paradoxa, Aloe albida, Khadia beswickii and Aloe
peglerae. The conservation programmes for each of these rare species are structured
slightly differently dependent on the plant’s specific needs
The Wits
Garden is, at present, collaborating with both Mpumalanga Parks Board and Gauteng’s
Department of Agriculture, Conservation, Environment and Land Affairs (DACEL). These
nature conservation authorities are primarily concerned with in situ conservation
activities which involve the ideal form of conservation – conserving the original
habitat intact – and they do not have the horticultural expertise and nursery
resources of the Botanical Garden which will, hopefully, be essential tools in saving the
four succulent species from possible extinction.
Each species
has been evaluated to establish its conservation needs, which could either involve pure ex
situ conservation through the cultivation of plants and the maintenance of a seed orchard;
or cultivation for the dissemination of material to the commercial nursery trade to
alleviate collecting pressure on the wild populations. Alternatively, the programme may
involve the further and somewhat controversial step of re-introduction of the species into
its historically natural habitat in the wild – or the even more controversial measure
of establishing a totally new population in suitable habitat in the wild.
According to
Hankey, relocation into the wild of plants grown en masse in nurseries is not a popular
conservation method. Modern schools of thought are, generally, not in favour of
re-introduction as a conservation method primarily because of the possible introduction of
pathogens into natural habitats. There is also a genetic concern because propagation under
nursery conditions means a high success rate – on average 90% of the seed will
produce plants that will grow into reproducing adults, whereas in the wild every 100 seeds
will only, again on average, produce one reproducing adult. In the unnatural nursery
conditions, genetic selection does not take place and when the plants are re-introduced
into the wild, weak genes that would never have survived in the wild are introduced back
into the population. If cuttings are used for the propagation of the plant species,
individuals with very limited genetic variation (clones) are produced.
The four
succulent species have been identified by the respective nature conservation authorities
as species with high priority conservation needs, primarily because of habitat destruction
but also, in the case of the aloes, because the plants have been over-collected for the
horticultural trade. The Garden is doing the horticultural research and cultivation of the
plants, establishing their germination and propagation requirements – including which
climatic and soil conditions they need and to which diseases they are susceptible.
Orbea paradoxa
This small plant, commonly known as the Paradoxical Orbea, is endemic to the
Maputaland Centre of Plant Endemism – which includes northern KwaZulu-Natal, the
Malelane/ Komatipoort area of Mpumalanga and a portion of Mozambique. The plant belongs to
the Stapelia family (Asclepiadaceae) which is known for the foul, carrion-like smell of
its flowers. The odour attracts fly species which are its pollinators. The plant has been
listed as endangered in previous Red Data Lists for the former Transvaal.
One of the
main populations of Orbea paradoxa was flooded through the building of a dam and
Mpumalanga Parks Board (MPB) rescued 13 plants which were given to the Wits Garden in a
drought stricken condition for propagation purposes in 1999. Mervyn Lotter serves as the
liaison person for MPB on this unusual collaborative initiative.
MPB has
identified a habitat deemed to be similar to the lost habitat and the idea is, eventually,
to introduce numbers of plants propagated by the Wits Garden to this ‘new’ site
where the plants are not considered to have occurred previously: a controversial action
and to be considered as highly experimental. Hankey pointed out that there were risks
involved, as there might well be a particular unidentified element necessary for the plant’s
survival that was absent from the proposed site. These uncertainties could include the
absence of the pollinator or possible league of pollinators from the proposed site.
Once the
required number of plants, about 500, has been propagated by Wits, the plan is to take
cuttings from the plants with a sterilised blade and to root these under sterile
conditions. It is these rooted cuttings that MPB, in conjunction with Wits, will introduce
to the chosen natural habitat. The planting out will be a joint operation. No soil will be
introduced as it is largely the soil that carries the pathogens – even if it is
sterilised soil, as nurseries are breeding grounds for disease. The plants will need to be
healthy and virus free at the time of taking the cuttings and the healthy cuttings will be
rooted in sterilised river sand with no organic content. Once the cuttings have rooted,
the sand will be washed off and the rooted cuttings treated with a Jeyes Fluid solution
prior to being planted out in the wild. Every effort will be made to avoid the transfer of
pathogens.
Hankey
pointed out that a favourable aspect was that the chosen site contained no existing wild
population which could be affected by pathogens. He confirmed that, at present, there were
in excess of 100 plants propagated by cuttings in the Wits nursery, meaning that the
project was well on its way.
He went on
to explain that propagation by cuttings had been the only possible route because in the
absence of the pollinator (an unidentified species of fly attracted to the carrion flower)
seed set had been non-existent, and hand pollination had been unsuccessful. He said that
the cuttings had been highly successful with 100% rooting rate being achieved. He pointed
out that Orbea paradoxa relied quite heavily on vegetative reproduction by means of
underground stolons in the wild, which he said was quite unusual for a Stapeliad.
Aloe albida
This miniature grass aloe with whitish flowers is endemic to a very narrow
range in the Barberton area of Mpumalanga extending slightly into Swaziland, where it
grows in the mist belt of the Saddleback Mountains. The area within which it is found is a
botanical hotspot and is called the Barberton Centre of Plant Endemism.
This small
aloe is highly valued by plant collectors because it is an excellent dwarf container
subject, it is rare and because the white colour is unusual in aloe species. It has, in
the past, been over-collected, particularly in the 1950s when collecting was at its height
(often referred to as the period of “aloe mania”) – and it is still known
to be illegally collected from accessible populations for the local and international
market.
It has a
limited distribution and its Afromontane grassland habitat has been extensively
transformed by afforestation over the years. In a paper on Aloe albida written by Hankey
and Lotter and delivered by Hankey at the Plant Science for Conservation Conference held
at Dublin University in July 2002, comment was made that the aloe had the same habitat
requirements as the exotic pine plantations and this had resulted in both loss of
populations and fragmentation. The lack of gene-flow between populations is conceived as a
long term threat to the survival of this species. Aloe albida is classified as endangered
on the IUCN Red Data List and is listed on Appendix 1 of CITES.
This
threatened plant needs to be grown at a high altitude and MPB therefore targeted the Wits
Botanical Garden to propagate the species and create a seed orchard. The concept is that
this ex situ produced seed will be taken back to the plant’s natural habitat and
broadcast into suitable niches in the grasslands. Populations that are now locally extinct
will be recreated in this way, weak populations will be reinforced and new populations
established in suitable habitat where the plant may historically have existed.
Introduction
into the wild by seed is a more natural process, allowing natural selection to continue
and it means that fungi and other pathogens, which can easily be transported on a fully
grown plant or in the soil that comes with it, will not accidentally be introduced into
the areas where an attempt is being made to re-establish populations.
This
co-operative conservation project also intends offering ongoing advice to land managers
concerning, amongst other aspects, the ideal time of year to burn firebreaks in sensitive
areas. The creation of corridors has been recommended to allow effective gene-flow between
populations, through the removal of strips of plantation to facilitate free movement of
insect pollinators between isolated populations.
Pollination
at the Wits Garden has to be effected by hand as the pollinator is absent from Gauteng. A
small camelhair paintbrush is used twice daily to effect pollination during the flowering
season which is in January and February, with sporadic flowering continuing into March.
The stigma of an individual flower becomes receptive only after the anthers have ripened
and the pollen been dispersed – to ensure cross- pollination. Hand pollination twice
a day ensures that all the ripe anthers and receptive stigmas are reached. This policy has
resulted in an increase in seed set and, according to Hankey, during the next flowering
season pollination may well be effected three times daily.
The plant
produces seed in April and May and the seed which is inclined to be heavily parasitised is
sprayed with a pesticide that has cypermethrin as its active ingredient. The thin papery
capsule drops its seeds within a day and seed has to be collected on a daily basis so that
it is not lost. All the seed is sown in October annually and there are well over 200
plants in the seed orchard, at present. Next year enough seed will be produced to allow
seed to be stored in air tight containers with sachets of silica gel to ensure that it
stays dry, after it has been treated with sulphur against the possibility of insect or
fungal attack. The longevity of the seed is unknown and this will be monitored with time.
The Wits
Garden has therefore established a substantial gene pool of propagation material from
mother stock provided by MPB from various localities. Although MPB retains ownership of
the material and will administer its distribution, the plants will be held at the Garden
where they can be closely monitored and propagation continued.
Khadia beswickii
The fleshy rootstock of various members of this genus, which belongs to the
family Mesembryan¬themaceae, is used as a fermentation agent in traditional beer making
and is commonly called the Khadi Root. Khadia beswickii is endemic to the Heidelberg area
of Gauteng where it is being threatened by expanding informal housing settlements. Nature
conservation (DACEL) is concerned about its long term future and has given the Wits Garden
material from the wild population so that the plants can be propagated to act as an ex
situ repository of genetic material, in case the natural population is wiped out in the
near future. Nature conservation is continuing the search for other populations in the
vicinity.
Thompson
Mutshinyalo (then with the Wits Garden) went to collect the seeds with Michele Pfab of
DACEL and initiated the propagation work at Wits. He has subsequently been transferred to
the Pretoria National Botanical Garden on being promoted to senior horticulturist and has
taken most of the material with him, as he has decided to research propagation methods on
K. beswickii as part of his B.Tech degree in Horticulture with Technikon SA.
Mutshinyalo
has found that the plant can be propagated from seed, stem cuttings or by means of
division. He is also believed to be the first person to succeed in getting the leaf of a
Mesembryanthemaceae species to root. He said that leaf cuttings could produce roots within
two weeks but did not develop a growing crown. He commented that this was a good sign of
strong callus development and had initiated the use of tissue culture – the results
of which were still pending.
He said
propagation from seed had to be done between September and March in a well drained growth
medium, covered by small granules of silica sand. He experienced a high germination rate
in pure washed river sand but the growth rate was very slow, whereas if the seed was sown
in a mixture of sand and peat based potting soil, the growth rate was fairly fast.
Stem
cuttings taken at the right time of year have often produced a 90-98% positive result.
Mutshinyalo currently believes that stem cuttings and seed are the most effective and
efficient ways of propagating this rare succulent plant. He has found that K. beswickii is
very susceptible to red spider and leaf scale.
Aloe peglerae
This peculiar stunted aloe, sometimes called the Red-hot Poker Aloe, is unique
in appearance when it is in flower and is found mainly on the Magaliesberg and
Witwatersberg, from Pretoria westwards to Rustenberg and southwards to Krugersdorp –
in both the North West Province and Gauteng. It is localised near densely populated areas
and has become critically rare largely because of habitat degradation but also because of
collection.
The Wits
Garden is working in conjunction with Gauteng’s DACEL, with Pfab once again serving
as the liaison person, to propagate plants from seed and create a seed orchard in the
Garden. The seed from this crop is earmarked for distribution to the horticultural
industry to try to alleviate the pressure on seed in the wild which is being extensively
collected.
The mother
plants propagated from seed provided to the Garden by DACEL from six sites on the
Magaliesberg will remain the property of DACEL and be held at the Garden over the long
term. This stock is genetically pure and essentially represents wild collected plants.
This ex situ source of genetic material at the Garden may be required at a future date if
a re-introduction programme becomes necessary. Seedlings propagated from the mother stock
will, however, eventually also be for sale to the nursery industry.
Aloe
peglerae is pollinated by sunbirds of which there are plenty in the Wits Garden. The seed
orchard now comprises 100 plants. According to Hankey there should be a substantial
seedset in 2003 after flowering in July and August and the first seed crop will be able to
be harvested. Up until now, there has only been sporadic flowering from the plants that
were planted out in open ground in 2000. This ex situ (not wild collected) seed will be
made available for impartial distribution to the horticultural industry, once DACEL has
established a system. The sale of the seed and plants will also allow the Wits Garden to
recover its costs.
-----
The Cities
for Climate Protection Programme implemented at Potchefstroom
Report
by Guillaume Nel and Hendriko Veldman of Potchefstroom City Council, and Esmé Snyman and
Johan G Nel of the Centre for Environmental Management, University of Potchefstroom
The
Potchefstroom City Council joined the Cities for Climate Protection (CCP) Programme of the
International Council for Local Environmental Initiatives (ICLEI) in 2001. The CCP
Programme is a performance-orientated campaign that offers local governments a framework
for developing a strategic agenda and projects to reduce global warming and air pollution
emissions, with the added benefit of improving the living conditions of local communities.
The CCP Programme empowers local governments to reduce greenhouse gas (GHG) emissions.
A number of
gases known as greenhouse gases, including carbon dioxide (CO2), methane (CH4) and nitrous
oxide (N2O) are transparent to incoming short wave radiation, but resist outgoing long
wave radiation. If the concentration of these gases begins to multiply in the troposphere,
it can trap the outgoing terrestrial radiation, resulting in potential global warming,
called the greenhouse effect. The greenhouse effect is not only of interest to
environmentalists and academics but is of importance to society because of the drastic
effects that global warming will have on water, food and energy supply.
The CCP
Programme provides local governments with a milestone framework, helps them to identify
the GHG emissions for their councils and communities, sets a reduction goal and develops
and implements an action plan to reach the proposed target.
The
milestones are the following:
*
to conduct a GHG
emissions inventory of current council and community activity and a forecast of GHG
emissions growth in the future;
*
to establish a GHG
emissions reduction goal;
*
to develop a local
action plan;
*
to implement the local
action plan; and
*
to monitor and report
on the implementation of the local action plan.
Strategy followed in
Potchefstroom
An interdepartmental CCP Implementation Committee was formed to guide the
implementation process, since it was argued that unless all relevant directorates gave
their co-operation, no progress would be made. The experience of Potchefstroom suggests
that it is possibly easier to achieve co-operation in a city of intermediate size than in
a larger city, because on the one hand, fewer people are involved in the process and the
divisions between depart¬ments are not as clearly defined as in larger cities. On the
other hand, cities of intermediate size have an advantage over smaller cities and towns in
that they have sufficient resources and the necessary infrastructure to implement such a
programme successfully.
One of the
challenges is to get mayors and councillors enthusiastic about sustainability issues in
view of other pressing socio-political and socio-economic issues. One possible strategy to
elicit the co-operation of decision makers at local level is to combine programmes that
aim to achieve improvements in environmental management performance with opportunities to
save costs, create jobs, transfer skills and reduce poverty.
An important
contributing factor to the progress made in Potchefstroom is that the CCP Programme has
the political support of the executive mayor of Potchefstroom, Councillor Satish Roopa.
Being well aware of the importance of environmental issues, he established a Mayoral
Environmental Advisory Committee to inform the Council about the implications of all
activities impacting on the environment. The enthusiasm of the executive mayor has also
resulted in his participation in global events related to the Programme.
Projects related to the
Potchefstroom CCP Programme
The City of Potchefstroom has identified a number of projects that are aimed at
reducing its contribution to GHG emissions. Some of the projects ensure the improvement in
energy efficiencies of various facilities, while others ensure reductions in GHG levels by
means of CO2 sequestration, as well as reductions in emissions of CO2
equivalents by means of methane recovery. Some of these GHG reduction projects have been
concluded, while others are ongoing and new projects are being investigated and planned.
Upgrading of
streetlights
Two projects
have been identified to improve the energy efficiency of street lighting in the city. The
first project entailed the replacement of outdated light emitter technologies with more
energy efficient emitters in the city’s main thoroughfares. The second project
focused on making street lighting in residential areas more efficient. The latter is a
pilot project aimed at verifying social acceptance of the new technologies.
Thoroughfares:
A total of over seven thousand 200W incandescent streetlights has been upgraded with 125W
Mercury Vapour (MV) and 70W High Pressure Sodium (HPS) light emitters, respectively, in
all of the thoroughfares and in most of the residential areas in Potchefstroom. With MV
light emitters, an average energy saving of 23% has been achieved, while HPS light
emitters yield an average energy saving of 50,5%. In monetary terms, savings in energy
bills amount to an average annual saving of R84 762,65, while a saving of 334 300kg of CO2
is achieved. Currently 99% of all streetlights in thoroughfares have been replaced with
more efficient light emitters. Only 640 incandescent streetlights are still operational in
the City of Potchefstroom. The other lights have been retrofitted with 241 HPS light
emitters, 7 093 MV light emitters, over five hundred 250W MV at the taxi ranks and fourty
seven 400W light emitters on the highways.
Pilot study
– residential area: The city engineers were reluctant to replace existing 200W
incandescent or 125W MV light emitters with 70W HPS light emitters in residential areas,
as they argued that HPS emitters have an unacceptable colour rendering index – the
true colour of objects is not rendered. It is generally argued that people prefer white
lights in residential areas as they enhance recognition of colour. It is also argued that
the monochromatic nature of HPS lamps inhibits perception of the three-dimensional
properties of objects, making it difficult to recognise facial features. It was
there¬fore argued that retrofitting of inefficient light emitters in residential areas
needed to be done with circumspection, because of possible public opposition. It was
decided to identify a pilot project to test social acceptance of the more efficient HPS
light emitter technologies.
A
residential area was identified for a pilot project to replace 200W incandescent
streetlights with 70W HPS light emitters. One hundred and ten streetlights were replaced
at a cost of R65 700, excluding labour. A saving of 1 765 kWh per month has been achieved.
The projected annual savings in CO2 amounts to 18 000kg. If the outcome of the
evaluation is positive, further upgrading of residential streetlights will be done. A
further 1 330 incandescent streetlights will be upgraded with 70W HPS light emitters at a
cost of R65 per streetlight.
The
estimated additional energy saving will be 16,5 kWh per streetlight per month. The total
amount of CO2 saved annually as a result of upgrading of inefficient street
light emitters amounts to 362 103kg. In monetary terms the savings are R91 759 per year.
Retrofitting at the airport
In 2001 and 2002, the airport runway and taxiway were retrofitted with energy saving light
emitters. Actual energy saving in the first year was 58 251 kWh or R11 921 with a saving
of 48 614kg of CO2 per year.
Deployment
of a wind turbine at the airport is under investigation to reduce reliance on fossil based
energy even further.
Energy efficiency in
new municipal buildings
The design specifications of the new council chambers were audited against the
South African Energy and Demand Efficiency Standard (SAEDES). SAEDES is an energy
efficiency guideline for new and existing commercial buildings. The purpose of SAEDES is
to reduce the energy consumption and/or demand of buildings. Following the SAEDES audit,
modifications to design specifications were made to ensure that the new building was 100%
in conformance with SAEDES requirements. These modifications have achieved an annual
saving of 14 000kg of CO2 or R2 670 per year. In future all new council buildings will
conform to the SAEDES requirements. (See article on page 30 of this issue for more
detail.)
Recovering methane from the sewage treatment plant
The recovery of methane from the sewage treatment plant is the biggest contributor to the
GHG reduction programme in Potchefstroom. Methane is recovered from the sewage works to
curtail emissions into the atmosphere. This recovered energy source is used to incinerate
solid screenings from the inlet works. The incinerator used previously was fired by
diesel. Generation of methane is controlled to ensure that just enough methane is
generated to meet the needs of the incinerator. As incineration demand increases, more
methane will be generated under controlled conditions. As a result of improved control
over methane generation, significantly less methane is generated when compared to the
previous situation (see Table 1).
The CO2
equivalence of methane (CH4) is a CH4 to CO2 ratio of
1:21. The total improvement in GHG efficiencies that are attributed to upgrades made at
the sewage treatment works amounts to a saving of the equivalent of 16 304 tonnes of CO2
per year.
The
following parameters were also considered when the total contribution to improved
performance in GHG emissions was calculated:
*
contribution of CO2
generated by the sewage treatment process;
*
CO2
generated as a result of methane combustion;
*
improved efficiencies
due to incineration of sewage screenings using methane instead of diesel as fuel; and
*
increased energy
demand by the aerators to control methane production.
This project
elegantly combines financial savings with improvements in environmental performance, as
well as replacing fossil fuel with a sustainable energy source.
Tree planting aimed at sequestrating CO2 from the atmosphere
The City of Potchefstroom has embarked on a tree planting campaign in the poorer suburbs
of the city to enhance the leafy character of the city. A total number of 4 405 trees has
been planted since 1996 and a total of 14 208kg of CO2 has been sequestrated. A
CO2 sequestration model was developed and was endorsed by ICLEI.
Total improvements
The total improvement in GHG reduction achieved by the City of Potchefstroom is
listed in Table 2 and in Figure 1. The total reduction in CO2 emitted by the
city amounts to 12 616 tonnes per year or a reduction of 39, 8% as measured against the
baseline footprint of 1995.
Conclusion and next phase
Adoption and implementation of the Cities for Climate Protection programme by the City of
Potchefstroom has so far resulted in a 39,8% reduction of its CO2 footprint.
Should the CO2 be traded internationally at the conservative price of US$5,00
per ton, the city could generate an additional income of US$47 221,5 per year. In addition
to that, improved energy efficiencies in the city amount to a saving of US$65 000 per year
that could be utilised for socio-economic development projects.
The combined
results of improvements in environmental performance and financial savings has been met
with enthusiastic approval by political decision makers and city officials, to the extent
that environmental performance is now a fixed agenda point at council meetings. City
decision makers have also launched other sustainability and environmental performance
projects as a direct result of the successes achieved by the CCP programme.
Improvements
in energy efficiencies have been the catalyst in the transformation of the City of
Potchefstroom into a green city. Experience in the City has shown that improvements in
energy efficiencies may be achieved very cost effectively, while the return on investment
makes such projects financially viable.
The City
Council is already expanding its environmental projects to include closure of unsanitary
landfill practices and replacement with sanitary landfill practises, upgrading of the
wastewater treatment works, insurance of legal compliance by all the city’s
operations, following a legal compliance audit that has been conducted. Numerous
environmental projects will be launched under the banner of the Integrated Environmental
Plan – a sectoral plan in terms of the Integrated Development Planning (IDP) process.
-----
New council chambers claim green
building status
The new
council chambers for the Potchefstroom local authority, designed as an annexe to the
existing council offices and rates hall, are proclaimed by the city as “100% green”
and indeed as “the first totally green building in South Africa”. This label
simply denotes the building’s compliance with the draft South African Energy Demand
and Efficiency Standards (SAEDES) developed by the Department of Minerals and Energy in
consultation with the CSIR’s Green Buildings for Africa (GBA) programme. While the
council’s care and endeavour to create a ‘green’ building must be
commended, it should also be acknowledged that this is essentially a conventional
building, employing conventional electrical and mechanical systems, designed to optimise
energy efficiency.
Architect
Kirsten Boshoff from Studio Nouveau explains that the chambers were designed initially
without specific consideration of green principles. The building is linked to the existing
council offices but is, in effect, a separate facility, with its own systems and services.
It is designed to accommodate the auditorium – which can seat 70 councillors and 80
guests – for private and public council meetings, as well as a number of subsidiary
meeting rooms and service functions – a kitchen and ablution facilities.
The design
was put on hold when, in view of Potchefstroom’s participation in the Cities for
Climate Change Programme (see page 26), the city’s mayor called for a re-assessment
of the plans and the need to take account of green building principles.
Through
Professor LJ Grobler, president of the SA Association of Energy Engineers and currently
lecturing on energy efficiency in commercial buildings at Potchefstroom University’s
School for Mechanical and Materials Engineering, the School was appointed to evaluate the
design in terms of the draft SAEDES standard. The evaluation team from the School worked
with the professional consultants and with the electrical and mechanical contractors
through construction, with the aim of establishing a building that would achieve 100%
energy efficiency according to SAEDES.
This
appointment paralleled the work undertaken by Energy Cybernetics, a Potchefstroom based
company that has strong links with the School of Mechanical and Materials Engineering, in
the wider SAEDES pilot project. When GBA was commissioned by the DME to pilot the draft
SAEDES standard, it in turn appointed Energy Cybernetics to evaluate the application of
the draft standard in selected new and existing buildings, in order to assess its
workability and its effectiveness as a measure of energy efficiency. The new council
chambers in Potchefstroom was one of the buildings in the pilot programme and is the first
of the new buildings assessed that complies 100% with the SAEDES standard.
In the
council chambers project, the evaluation took account of the design of the building
envelope, the electrical systems for lighting and water heating, and the heating,
ventilation and air conditioning systems – from pumps and piping, to operations and
controls, to maintenance requirements over time. Changes recommended to meet the SAEDES
standard were made only where practical and economically viable.
Boshoff
admits that he was at first wary of the design review and what its implications might be,
but it became clear that no major redesign was required. Some adjustments had to be made
and certain new elements incorporated.
The building
had been conceived originally in clay facebrick and one of the changes required was that
all external walls should be cavity walls. The specification of 230mm brickwork was
replaced by 280mm, with a 50mm cavity to improve the insulation afforded by the building
envelope.
The
proportion of glazing to brick¬work in the envelope was considered acceptable and no
double-glazing was necessary. The north façade of the building is fully glazed but this
face is shaded by a portico which was seen to provide adequate protection against
excessive interior heat build-up from solar radiation. The auditorium itself, a double
volume space in the centre of the building, is entirely enclosed.
Initially,
there was a call for additional insulation to the domed concrete roof of the auditorium.
However, the client requested changes to the ceiling in this space and these overcame the
need for any further insulation. In a section of the building where a storeroom is tucked
under the raised floor of the auditorium, there was also a requirement for additional
insulation to be in¬stal¬led in order to reduce the transfer of heat through the floor.
Thus the
changes to the structure were minimal. Boshoff says that good design, in principle, should
automatically take account of climate and orientation and seek to build in passive
controls, as far as possible, to create a comfortable in¬terior climate. “The
difference now,” he says, “with developments like SAEDES, is that such
efficiencies – whether built-in or mechanical – can be measured.”
Other steps
taken in the interests of creating a green building included the specification of certain
materials. Floor finishes in natural stone, for example, have the advantage of promoting
heat absorption in the floor during winter months, and the added green advantage that the
material can be recycled. However, the latter principle was not generally ap¬plied in the
specification of materials. Consideration of the source of the stone, or those of other,
manufactured materials, their transportation to site and so on, do not form part of the
SAEDES evaluation.
The
installation of dual flush toilets in the ablution facilities and low-flow taps, which
incorporate an adjustable valve to limit water flow, are other green measures implemented
– to control water consumption.
According to
Boshoff, the changes made did not add substantially to the cost of construction.
Energy
efficiency consultant, Christo van der Merwe, who is currently involved in doctoral
studies at the School of Mechanical and Materials Engineering and who is also part of the
Energy Cybernetics team, says that SAEDES allows for flexibility in respect of budget
limitations and basic practicalities. The overall aim is to establish a workable solution
that will produce an energy-efficient building that suits its purpose and the client’s
needs.
According to
Van der Merwe, the standard is structured to take account of the type of building, its
function and the climate in which it is located. It deals with the building envelope and
mechanical and electrical engineering systems. He explains that SAEDES presents a dual
standard which is at one level prescriptive – identifying ideal energy demand and
efficiency levels, and at the other a performance standard – acknowledging that
costs, availability, or other such factors may influence decisions on the implementation
of energy efficiency measures in the final building. This dual standard is intended to
allow for architectural and engineering flexibility. The performance measures of
compliance may be met in any number of different ways and the system allows that
opportunities to optimise energy efficiency may be compromised by other practical factors.
“As
well as providing input to the professional team,” says Van der Merwe, “we were
involved on site with the electrical and mechanical contractors, to ensure that the energy
efficiency measures agreed to could be implemented. Where problems arose, solutions were
sought with the contractors at monthly site meetings.”
For example,
it was noted in the initial assessment that the efficiency of the air conditioning system
could be improved. The fresh-air fan in the system specified was one that would run at
constant speed, which increases electricity demand unnecessarily. “However,” Van
der Merwe explains, “the option of introducing a variable speed motor to the
specified system, meant not only an extra cost but also that the client would lose any
guarantee on the system. Clearly it was most practical to go with the system as it is
available.”
The
application of SAEDES allows for this sort of compromise since it is designed to seek the
most practical solution. It does, however, force the electrical and mechanical engineers,
as well as architects and others involved in design and construction, to consider energy
efficiency, to look for the most energy efficient options and to record the reasons why
such options are not implemented, if that should be the case. Over time, as demand for
energy efficient systems increases, it can be anticipated that manufacturers will also
take up this challenge.
A further
aspect of SAEDES is that it calls for ongoing evaluations on a regular, proposed annual,
basis so that adjustments can be made with any changes in a building’s function, and
systems can be upgraded if new technologies become available and prove appropriate.
Other
buildings in the broader SAEDES pilot programme included Mutual Park in Cape Town and the
Mechanical Engineering and Administration buildings at the University of Pretoria –
as the three existing buildings. New projects included the international terminal building
at Cape Town International Airport and the Cape Town International Convention Centre. With
regard to the airport terminal, Neil Oliver from GBA says that the SAEDES assessment took
the form of a design evaluation, as the building was already under construction. At the
CTICC only a prescriptive evaluation was performed; its implementation and an evaluation
of the relative performance of the building should be undertaken once the convention
centre is operational.
Based on the
practical evaluations of the applicability of the draft standard in this pilot study, GBA
has reported back to the DME on the programme. According to Oliver, the intention is to
establish an energy efficiency standard under the National Standards of South Africa (NSSA
– formerly the SABS). The DME has recently made a submission to NSSA in this regard
and the next step is for NSSA to convene a specialist task team to review the SAEDES
draft, in light of the pilot application report, and to formalise the energy efficiency
standard. It is expected that this new standard will soon become part of the national
standards framework.
Professional Team
Architects: Studio Nouveau
Quantity surveyors: McLachlan Du Plooy NW
(Pty) Ltd
Consulting structural engineers: BKS (Pty) Ltd
Consulting civil engineers: BKS (Pty) Ltd
Consulting electrical & mechanical engineers: Deltaplan
Mechanical engineer: Deltaplan
Main contractor: Tronkon
-----
Asbestos removal in buildings
An
accidental find of old and disintegrating asbestos ceiling insulation during the recent
conversion and refurbishment of a double-storey building in Bree Street, Cape Town, meant
that contractors, Gordon Verhoef & Krause, had to ensure its safe removal and
disposal, in line with the new Asbestos Regulations. Leigh Darroll spoke to Anton Krause
at GV&K about this process and the ramifications of the Asbestos Regulations for the
broader building industry.
Krause
reports a growing demand for asbestos inspection and removal or for advice on asbestos
risks in buildings from commercial and industrial property owners and even in the
residential market. He sees this as a result not only of the new regulations, which impose
a legal obligation on property owners and employers to eliminate asbestos risks in the
workplace, but also of the high profile that asbestos litigation has seen in recent
months.
Asbestos
containing materials were used in many older buildings – dating from the 1950s and
’60s or earlier – asbestos cement roof sheeting, ceiling boards and building
panels, for example, as well as dry walling, ceiling insulation and lagging on pipes and
other components, particularly in industrial water heating systems. Asbestos pipe lagging
is a serious problem in older public and institutional buildings – hospitals,
prisons, schools – as well as in hotels, office buildings and factories. Asbestos was
even used in washers in plumbing systems and in plant pots. Vinyl floor tiles and vinyl
sheeting also contain a proportion of asbestos, although the manufacture of these
products, like asbestos cement products, has now been outlawed in South Africa.
Krause
points out that the regulations only require asbestos to be removed where it presents a
health hazard. This was the case in the Bree Street project because the material was old
and friable and because it would be disturbed by the refurbishment work under way. In
installations where the material is intact – for example, in ceiling panels or roof
sheets that have not deteriorated – it simply needs to be noted and the potential
risk managed.
The Asbestos
Regulations 2001 were promulgated under the Occupational Health & Safety Act (OHSA),
1993, and published in February 2002. The regulations derive from the earlier Guidelines
on Management of Asbestos Related Problems, which were drawn up by an interdepartmental
task team – involving the Departments of Labour, Health, Minerals & Energy,
Environmental Affairs and Tourism, and Water Affairs and Forestry – and which address
the wide ranging problems arising from asbestos mining, through transport, to materials
manufacturing, installations, cleaning or maintenance, removal and disposal. The
regulations deal with the control and prevention of exposure to asbestos in the work
environment. As part of the OHSA, they pertain to the health and safety of anyone involved
in working asbestos as well as those in any way at risk in their places of work. This
article confines itself to dealing with the regulations only as they relate to the
management or removal of asbestos containing materials in buildings.
An inventory and risk
assessment
The first requirement of the regulations is that property owners must prepare
an inventory of asbestos or asbestos containing materials in their buildings. The presence
of these materials has to be documented and located on a plan of the building. As Krause
points out, such an inventory would have prevented the accidental encounter in the Bree
Street project and appropriate steps could have been taken in advance of the refurbishment
work beginning. As it was, the new owners of the building had not inherited any such
inventory and willingly agreed to the additional time and costs that would be incurred to
remove the asbestos.
Where
buildings are tenanted rather than owner occupied, the owner of the building is obliged to
make an asbestos inventory available to the tenants. Similarly, where construction or
refurbishment work is to be carried out, contractors are entitled to call for a copy of
the asbestos inventory before tendering on the project. A property owner that does not
prepare an inventory can be charged with negligence in terms of the OHSA.
Ideally, the
inventory should be prepared by an Approved Asbestos Inspection Authority (AIA), working
in collaboration with health and safety representatives where appropriate. The Directorate
of Occupational Health and Safety at the Department of Labour (DoL) maintains a register
of AIAs. The condition of the materials must be examined regularly so that any risk that
may arise can be addressed.
Where there
is a risk that anyone working in the building may be exposed to asbestos dust, an
assessment of the exposure risk must be conducted and the environment must be reassessed
at regular intervals – at least every two years – to ensure that the asbestos
hazard is controlled. The onus is on the employer to ensure that a proper assessment is
conducted. An air-monitoring programme should be implemented and, as a specialist
programme, this should be conducted by an AIA or by an occupational hygienist registered
with the SA Institute of Occupational Hygienists. The AIA is accountable for the
monitoring process and for the validity and accuracy of all measurements.
The
occupational exposure limit (OEL) for airborne asbestos is currently 0,2 fibres per
millilitre of air over a four-hour working period. Obviously, the concentration of
airborne asbestos in the workplace should be nil, or at least below the OEL. Where
asbestos concentration levels cannot be contained below this limit – in working,
cutting or removing asbestos, for example – approved equipment, work processes and
protective measures have to be employed.
Asbestos removal and disposal
Only asbestos contractors registered with the DoL may undertake demolition work where
asbestos materials are involved and the removal of those materials. GV&K is a
registered asbestos contractor, having begun the process of acquiring the prescribed
equipment and training specialist work teams when the Asbestos Regulations were being
drafted.
Where
registered asbestos contractors are appointed to a project, they are required to submit a
work plan, already signed by an AIA, to the DoL for approval before work can proceed. The
Department has prepared guidelines for such work plans, which are available to registered
contractors.
The work
plan requires, amongst other things, that the level of asbestos fibres in the air must be
assessed prior to removal work beginning, and at four-hour intervals during the course of
work. This air monitoring procedure enables the contractor to track exposure levels and to
take action to limit them as far as possible.
Wet removal
methods, using specialised vacuum equipment, are pre¬fera¬ble as they reduce the amount
of asbestos dust in the air and hence the risk. The use of compressed air to clean away
asbestos or asbestos dust is prohibited. The cleared asbestos materials have to be double
bagged and the bags clearly labelled before disposal.
Ideally, the
work will be carried out when the building is unoccupied. In the Bree Street project,
asbestos removal was done over the weekends. Even though the building itself was empty
during the refurbishment contract, weekend work reduced the risk to people in neighbouring
buildings.
The work
area has to be isolated and sealed off with plastic sheeting or a similar material that
will close all air passageways between the work area and its surrounds. There are strict
requirements in respect of personal protective clothing and respiratory equipment and
these items cannot be removed from the contaminated site except when sealed in impermeable
containers to be transferred for washing or repair.
The
containment of the site and the need to eliminate any risk of transferring asbestos fibres
or dust outside of it, also require the provision of portable showers on site, with ‘dirty’
change rooms located before the showers and ‘clean’ change rooms after them, in
a one-way exit. Separate storage lockers have to be provided for used protective clothing
and for the personal clothing of the work team.
GV&K
used a team of 12 men for the asbestos removal task in the Bree Street project. Krause
explains that the company’s asbestos removal teams are trained by AIAs. They are
fully informed of the risks of the work so that they understand the need to follow
prescribed procedures and can take appropriate remedial action when necessary. In terms of
the regulations, all such employees have to be medically assessed on a regular basis.
Training updates are required whenever new equipment becomes available or new work methods
are introduced.
As a
hazardous waste substance, asbestos has to be disposed of by specialist waste contractors
and can only be dumped at hazardous waste sites. GV&K subcontracts asbestos disposal
to a specialist waste contractor.
Record keeping
Record keeping is emphasised in the regulations. Asbestos inventories must be
kept for 40 years, records of maintenance and control measures for three years, and
assessments and air monitoring records for 40 years. Records of employee training must be
kept for the duration of employment and medical records of all personnel involved in any
asbestos related work must be kept for 40 years.
On asbestos cement
products
Although asbestos cement building materials are reportedly no longer
manufactured in South Africa, these products were widely used historically and asbestos
cement roof sheeting is apparently still imported from Zimbabwe. These products are
specifically addressed in the Asbestos Regulations.
Anyone
working with asbestos cement products has to take special precautions to avoid accidents
and to prevent the release of asbestos into the environment. Hand or power tools that do
not generate unnecessary dust must be used and anyone cutting asbestos cement products
must wear an approved respirator.
Asbestos
cement materials should be painted or otherwise coated to prevent release of the fibres
and inhibit growth of lichen and moss which can accelerate the deterioration of the
material.
Dry
brushing, scraping, sanding and abrasive cleaning techniques are prohibited. Roof cleaning
with high-pressure water jets is permitted only with a hooded hose that prevents dispersal
of the contaminated water. Water polluted with asbestos fibres must be filtered and the
residue disposed of safely.
-----
Environmental award for eco-landscaping
This year
the DaimlerChrysler Environmental Award was won by the head office site in Pretoria West.
The site was selected from all of DaimlerChrysler’s office and factory sites
world-wide. The Award was made in the ‘non-productive category’. Carol Knoll
spoke to contractor Dan Barwick of Contour Landscapes on a visit to the site and to Roy
Trendler of Sunkloof Nursery who was responsible for the design and supplied the plants.
There has been a marked increase in wildlife diversity on site since the eco-landscaping
programme was implemented some eighteen months ago.
Roy Trendler
is well known for his eco-landscaping projects – projects that are designed to
attract wildlife into man-made landscapes. He maintains in general terms that, ideally,
four different habitat types need to be created artificially in the corporate landscape,
urban park or garden or on the golf course to encourage a large spectrum of different
insect, bird, reptile, amphibian and small mammal species.
These four
habitat types comprise a so called ‘exclusion area’ which should be a densely
planted section, the equivalent of a wilderness area in conservation terms: a stretch that
is not frequented by people so that the shier birds and animals can find refuge. Secondly,
an ‘open grassland area’ is required and this could comprise an expanse of mowed
lawn which will attract bolder bird species and those with longer legs that need runways
for take off, including a belt of long veld grass which will serve to feed seed-eating
birds.
There should
be a ‘canopy zone’ – a treed area under which there is human activity and
bird life is unlikely to be at the lower levels but will thrive in the tree canopies.
Trendler advocates that large invasive trees should not be ruthlessly hacked out of
gardens, but ring barked so that they will only die over time, once newly planted
indigenous trees have had time to mature. Even when the old trees are dead they will
afford protection to the indigenous saplings, support bird’s nests and provide
roosting spots. The last of the four habitat types is the ‘wetland area’ –
open water and a belt of marshland. This will attract the richest and most varied
wildlife.
At the
DaimlerChrysler site, the necessary compromise was reached to accommodate both humans (1
200 people work at the head office) and animals and to make the site aesthetically
acceptable. Mani¬cured areas have been retained and more natural areas with appeal for
wildlife have been kept largely to the southern side of the two dams on site, bordering on
the Hennops River. The exclusion zone falls between the dams and the river and there are
dense plantings of appropriate indigenous trees to enlarge the extent of natural growth
adjacent to the river, and nesting logs have been carefully positioned in the existing
riverine trees.
According to
Trendler, primary nesters, such as barbets, prefer to undertake the process of hollowing
out the logs themselves and the provision of solid sisal logs or sections of tree trunks
from species such as the soft wooded Syringa (which needs to be eradicated over the longer
period as it is a listed category 3 invader) are appropriate for these bird species.
Secondary nesters such as starlings will only nest in logs that have already been hollowed
out.
Trendler
advocates that garden refuse or debris in the form of stones, dead wood and other organic
matter should not be removed from site. Large piles of chopped up timber, that Working for
Water were asked to leave behind after their clean-up along this section of the Hennops,
are in evidence in the exclusion zone at DaimlerChrysler, as they play a vital ecological
role, providing habitat for myriads of insect species, reptiles and small mammals. These
piles of rocks and wood also provide natural nesting sites for birds which nest at ground
level, such as the Spotted Eagle Owl.
Working for
Water’s teams have removed large stands of Black Locust (Robinia psuedoacacia) and
White Poplar (Populus alba) and other thirsty invaders along this part of the Hennops, and
have been in to do follow-up work.
There is an
interesting jogging path or walkway which runs along the southern periphery of both dams
on the DaimlerChrysler site, providing a view over the marginal plantings and across the
open water. The pathway has been planted with plugs of the exotic groundcover, Phyla
nodiflora, commonly called Daisy Lawn. This prostrate species is clearly enormously hardy
as it grows with ease on this highly compacted pathway, which the DaimlerChrysler
employees use extensively during lunch hour, but the plant has no evident invasive
properties. Trendler says that they (he and Dirk Neiteler of Sunkloof, who was largely
responsible for the plant choices) tried to avoid planting lawn in areas close to the
water, as particularly the exotic Kikuyu but also the indigenous Cynodon dactylon
varieties are inclined to encroach into the water. The Daisy Lawn can be mowed with a
cylindrical mower to a low height, gives good coverage and is easily maintained.
The dense
band of supplementary indigenous planting between the pathway and the existing riverine
vegetation is largely locally indigenous and includes Combretum erythrophyllum – the
River Bushwillow which is the most dominant species growing along this stretch of the
Hennops, Salix mucronata (Cape Willow), Celtis africana (White Stinkwood), Diospyros
lycioides (Blue¬bush), Leucosidea sericea (Ouhout), Rhamnus prinoides (Glossy-leaf),
Grewia occidentalis (Cross-berry), Ehretia rigida (Deurmekaarbos), Halleria lucida (Tree
Fuchsia), Buddleja saligna and auriculata – although the latter species is not
locally indigenous, Trendler comments that it is an excellent plant for attracting
butterflies. The small trees were planted just before winter and there were unfortunately
some mortalities but this is not evident as the planting is so dense.
Contour
Landscapes was originally chosen for the job of rehabilitating the farm dams on the site
because of Dan Barwick’s previous experience with dam construction. Landscape
architect Alan Rosendal mapped the dams with the islands which were already in existence.
The large exotic Salix babylonica (Weeping Willows) were retained on the islands because
they were the only appropriate nesting sites for herons and egrets. The three original
farm dams which were being eroded by wave action and crab activity were converted into two
larger dams. The dams which draw water out of the Hennops by means of a canal and pipe
feed are used for the irrigation of the landscaping at DaimlerChrysler. They also serve
aesthetic purposes at the entrance to the head office, as well as attracting diverse
birdlife.
Additionally,
the dams function to improve water quality and the water that is returned to the Hennops
is much cleaner than the water which enters the dams. The water from the river which has a
high e coli count is initially fed into a filtration pond planted with reeds and bulrushes
to remove nitrates from the water. Sediment settles in this pond and then the water is fed
over an aeration weir into the first of the two large dams. The water is gravity fed from
one dam to the other and finally re-enters the river over a spillway.
All exotic
trees within 75m of the river have been removed because of their tendency to use large
quantities of water when it is available and DaimlerChrysler have put in place a five year
plan to remove all exotics from their 65ha site and to replace these with indigenous
plantings. Although expanses of water consumptive Kikuyu lawn have been retained, it is
intended that this will be replaced with indigenous lawn over time, and the edges are well
maintained to stop the Kikuyu from encroaching into the marginal plantings.
At the start
of the rehabilitation of the dams, Contour Landscapes removed 7000m3 of sludge which had
built up on the bottoms of the old farm dams and brought in 6 000m3 of rip-rap to line the
dams and guard against further erosion. The rip-rap was placed by hand. Some of the rock
was quarried on a site adjacent to the western of the two dams and this quarried area is
now being rehabilitated into reed¬beds. Agricultural lime was added to the bases of the
dams so that the pH of the water was conducive to plant growth. None of the embankments of
the dams are steeper than 1:3. The dams were stocked with 7 000 Mocambiquan Tilapia.
Barwick says that it is believed that 40% of fingerlings are depleted by fish-eating
waterfowl within the first month after stocking. The population of indigenous Tilapia
seems to have stabilised over time and the exotic carp and barbel that have come in from
the river are gradually being fished out.
When the
refurbishment of the dams was completed, Sunkloof Nursery won the tender for the design
and supply of indigenous plant material around the dams and be¬cause of budget
constraints, large quantities of the plants were supplied in plug form for the marginal
and other plantings. Contour Landscapes won the tender for the installation and
maintenance of the planting. Barwick comments on the excellent growth rate of these plugs
over an 18 month period on this very cold site and in the base of hard, infertile churt
(decomposed dolomite) which was used to line the embankments of the dam. The marsh plants
for the marginal plantings included varieties of sedge and wetland grasses such as
Schoenoplectus corymbosus, Cyperus papyrus, Cyperus alternifolius, Juncus effusus and
krausii and Isolepis costata (previously Scirpus); along with the bulrush, Typha capensis
and the Phragmites australis reed; and interspersed with colourful marsh plants such as
Hesperantha coccinea (Crimson Flag), various Crinum species (River and Vlei Lilies),
Zantedeschia spp (Arum Lilies), Kniphofia uvaria (one of the marshland red hot pokers) and
the water loving perennial, Gomphostigma virgatum (Otterbossie). The Crocosmias
(indigenous Crocus species) which were planted a little away from the embankments of the
dam have largely been eaten by the resident porcupines, of which there appear to be a fair
number.
Two otter
dens or, more correctly, holts were built into the embankment of the western dam which is
further away from regular human activity. Trendler describes the holts as being 1m2 of
space dug out in the bank of the dam, lined with brick, while two pipes at water level
provide the otters with access to the holt (see drawing). Barwick comments that there have
been sitings of otter around the dam and signs of their presence there in the form of
remnant shells of crabs that they have eaten. Areas of river sand on the edge of the water
are kept clear of marginal vegetation to allow leguans access to the water, and these
reptiles are often sited.
Rocks and
dead trees have been positioned in the dams which are relatively shallow to serve as
perches for fish-eating birds, and a portion of the embankment of the eastern dam has been
left bare to encourage bee-eaters to hollow-out the burrows that serve as their nests.
Barwick comments that this has not as yet been utilised by the birds and probably needs to
be built up slightly higher to become functional.
According to
Barwick, the most common birds around the dams are Sacred Ibis, Whitefaced Duck, various
Cormorant species and Pied Kingfisher, while Grant Fairley (also of Countour Landscapes)
says that Countour has recently implemented a bird, reptile and mammal checklist on site
to monitor wildlife populations. He comments that some interesting bird sitings have been
the Green-backed Heron, Blackcrowned Night Heron, Hamerkop, African Black Duck, Wood
Sandpiper, Giant, Malachite and Woodland Kingfisher and the African Grey Hornbill.
West of the
western dam is an area which has been planted with a variety of veld grasses, either
plugged or seeded, which is attracting seed-eating birds. Species such as Melinus repens
(Natal Red Top), Miscanthus capensis (Daba Grass), Eragrostis curvula (Weeping Love
Grass), Themeda triandra (Rooigras) and Hyparrhenia hirta (Common Thatching Grass) have
been used.
Countour
Landscapes has instituted an organic waste management operation on the DaimlerChrysler
site. All garden waste including grass clippings, prunings, dead leaves and flowers and
the invasive plants that are being removed on an ongoing basis are carted to a recycling
area where they are processed. According to Fairley, the first step is to chip or shred
the material and then to compost it for a minimum period of eight weeks. Following this
the material is sieved to separate the fine material from the coarser. The coarser
material is then re-applied to the landscape in the form of mulch, while the finer
material is composted further, ensuring that temperatures reached during the composting
process are high enough to destroy most of the weed seeds. Barwick comments that this
recycling process is not only environmentally sound but reduces the need to buy-in organic
material for soil amelioration and reduces maintenance costs as a result.
Barwick gave
credit to the recently retired site services manager at the head office site, Barry
Styles, for his continued support of the effort to turn the garden into a nature friendly
landscape. He added that the newly appointed manager, Cornelius Jonker, was clearly also
very much in favour of the eco-landscaping programme. |
