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Frequently Asked Questions about SCB’s investment in carbon offsets at the Baviaanskloof Megareserve, South Africa

by Paul Beier

Who owns the land? What kind of land is it?

Paul Beier points at the lower slopes where SCB’s investment will restore subtropical thicket in Baviaanskloof.

The thicket areas to be restored were degraded by conversion of thicket to livestock pastures; browsing by goats was the main cause of degradation. These degraded lands are now part of the Baviaanskloof Megareserve, located in the Cape Floristic Kingdom, the most threatened of the world’s 5 floristic kingdoms, with a land area less than 5% of any other floristic kingdom and plant endemism of 68%. The Baviaanskloof Megareserve is important because it is the largest area protecting intact swaths of this floristic kingdom, including elevational gradients from the ocean into interior mountains, spanning almost every biome in the floristic kingdom. UNESCO designated Baviaanskloof as a World Heritage Site because of its importance in conserving 5 of the 7 Cape Floristic biomes, including large scale ecological and evolutionary processes such as herbivory by megaherbivores, disturbance regimes, and response to climate change. Most of the Baviaanskloof has been untouched by humans for millennia due to its rugged terrain, thick vegetation, and dangerous mammals. The Eastern Cape Parks Board owns and manages the Megareserve; the Parks Board has acquired many lowland areas (including the areas to be restored) because these areas are critical to protecting the rivers that provide connectivity to the conserved landscape, as well as high-quality water for human use. No people were involuntarily expropriated from the land where our restoration project is to occur. Most project workers are being recruited from several small villages with high unemployment rates within the Megareserve.

Who is running the restoration project?

The restoration effort is run and funded by a poverty eradication program of the government of South Africa, namely the Working for Woodlands Program. As the name of the program implies, it is intended to put people to work in projects that improve the ecological integrity of degraded woodlands. As a subsidiary of the Working-for-Water Program, implicit goals include increased resilience to alien plant invaders, increased water quantity and water quality in South Africa. This particular effort on the Baviaanskloof Megareserve is one of many projects in the Working for Water program, and is being carried out collaboratively with the Eastern Cape Parks Board and other partners.

Will the project really alleviate poverty?
Most project workers are being recruited from several small villages with high unemployment rates within the Megareserve. Outstanding workers are being trained to become managers and founders of nurseries and restoration projects elsewhere.

Most unskilled workers are recruited and trained from the impoverished communities in and around the Megareserve. The Megareserve is also engaged in an ambitious riparian wetland restoration project (funded by WWF). Between these two efforts, there is at least a decade of work available in the Megareserve. Although senior staff on the Baviaanskloof project are educated persons from outside the Megareserve, the senior staff persons are aggressively identifying outstanding local workers and developing their skills to become managers and founders of nurseries and restoration projects elsewhere. In my brief visit to a small portion of the Eastern Cape, I was astounded at the massive invasion of riparian areas, upland flats, and steep slopes by a variety of exotic plant species. South Africa needs to rehabilitate hundred of thousands of hectares blighted by invasive plants and habitat degradation. Over the past 10 years, South Africa has created many new protected areas, and massively expanded many others. One paper at the SCB meetings documented substantial economic growth at 19 Eastern Cape communities near new parks, so we can expect marginally profitable farms to continue to be replaced by nature tourism. Thus restoration-related industries can expect several decades of economically-viable activity. 

How much carbon will be stored per hectare?
Estimates of carbon storage are based on thousands of samples of plant tissues from all major species in subtropical thicket. To avoid overstating the amount of carbon offset, SCB is purchasing only the carbon to be stored in the dominant and best-studied plant species, elephant bush (Portulacaria afra).

The estimates of carbon storage are scientifically rigorous and very conservative. I visited a facility with several railroad container bins containing hundreds of labeled bags of clipped, dried vegetation from plots at various elevations and aspects. Each bag represents the carbon of a particular stratum (height above or below ground) of a particular plant on a particular plot. The dried weights of each plant and soil sample have been used to generate curves of above-ground carbon as a function of plant diameter and height for various slopes, aspects, and elevations. Data are particularly rich for Portulacaria afra (spekboom, elephant bush), the dominant plant in some forms of the subtropical thicket biome, contributing up to 70% of the canopy in some stands. Spekboom stores two-thirds of its carbon in soil and litter; both the living tissues and litter are highly fire-resistant. Fortunately, some local farmers restored some areas to spekboom over the past 30 years, and scientists have sampled these sites to directly estimate the 30-year trajectory of carbon storage. Although this empirical time series is available only for some aspects and slopes, these data provide a valuable adjunct to estimates based on plant diameter and height. For purposes of the SCB contract, we estimate carbon storage per hectare based solely on spekboom. This is thus a conservative estimate of the actual amount of carbon likely to be stored by multiple species. Basing the estimate on spekboom alone is appropriate because spekboom will be the first species planted, and it is the only species for which detailed multifactorial trials have been conducted to maximize survival of outplanted cuttings.

The thick succulent stems of spekboom readily sprout when a freshly-cut branch is simply inserted into soil. I visited a large site where fully-replicated multifactorial trials are suggesting the optimal size of cutting, density of planting, clumpiness of planting, and soil preparation for both survival and growth of cuttings. In another set of 75 plots, one plot was planted each week near a weather station to determine optimal season for planting, and how weather affects survival. This is not a slapdash effort!

In a worst-case scenario, spekboom may be the only species to re-establish on some sites. The differential in carbon pools between intact and pristine thicket varies depending on the thicket type and the severity of degradation.  There are 112 thicket types and each one varies in terms of percent cover of spekboom. Also, the longer the time since degradation, the greater the C leakage from the soil. Spekboom should store 4t C/ha/y, or about 10-15 tonnes CO2e/ha per year.  This is currently selling at $5/tonne = $50-$75 per ha per year.

Total tonnage stored also depends on how many hectares are planted and maintained by our dollars. The planting costs in initial trials have been about R5,000/ha ($700/ha) but Mike Powell (chief technical advisor for Working for Water on this project) estimates that the cost will get down to about R1,500/ha ($200/ha).

How do you know you won’t end up with a spekboom monoculture instead of restored subtropical thicket with its full plant diversity?

The 30-year old plots (above) include other native plants that followed the spekboom plantings. Because the project would like to sell additional biodiversity benefits for restored subtropical thicket, they are committed to monitoring and learning how to recruit other species, and learning which species need assistance to recolonize a site. In an ongoing experiment, spekboom plants are being infected with mistletoe to attract birds to the mistletoe seeds, in the hope that the birds will defecate viable seeds of other plants into a spekboom stand. It is hoped that low-cost measures like this can kick-start the process of assembling a fully-restored thicket. Plans and greenhouse experiments are underway to restore some canopy-emergent plants expected to need assistance.

So SCB is paying for the minimum amount of carbon that will be stored in spekboom over 30 years – the actual carbon may well be several times this amount. Does SCB get to sell the excess tons of carbon on the world market?

Dear questioner, you understand these issues so well that you are cordially invited to join our committee! So you also know that, in addition to excess carbon tonnage, our restored hectares will also generate increased yields of high-quality water that may also be marketable in the future. And there is already an emerging market in biodiversity credits that should be willing to pay for restored subtropical thicket once the project can demonstrate that biodiversity benchmarks have been reached. However, SCB’s contract allows Working for Water or Eastern Cape Parks Board to retain rights to these profits. Why? First, the agencies took a gamble when they decided to invest over 30 times SCB’s investment just to get the project to the point where it seemed an attractive investment to SCB. We want to reward that sort of risk-taking! Second, we want the local agencies to have an incentive to do more than the minimum. While I have full confidence in the good faith of today’s managers, profit would help motivate managers in 2038 to add value to the effort. Finally, as one of the first biodiversity-community-carbon projects likely to show tangible results, this project will be watched by others around the world. We’d like them to become fabulously rich, so that others will follow their example!

How can I learn more about carbon offsets and climate change?

There is a lot of great information available on the internet. As of mid-2007, the most useful source of information about triple-benefit projects is the Climate, Community, & Biodiversity Alliance (

I’ve heard that carbon offsets are nothing more than a “license to pollute” – a meaningless feel-good fig-leaf that allows us to continue our addiction to fossil fuels. Why is SCB dignifying this practice?

The subtropical thicket on this slope has been degraded by decades of goat browsing, but is now protected in the Baviannskloof Megareserve. SCB dollars will restore the thicket on these slopes. SCB gets credit for new carbon stored on the site. Eastern Cape Parks retains rights to additional biodiversity credits that may accrue.

Wow, these questions are getting hard! There is some merit to this criticism, in that re-storing carbon should rightfully be the last course of action among the admonitions to “reduce, replace, and re-store.” SCB is looking for ways to reduce the amount of we emit. Because jet fuel to bring members to our global meeting accounts for about 95% of our impact, the only way to make a large reduction would be to reduce the frequency of our global meeting. The Board is thinking seriously about whether face-to-face meetings to build our global community are so important that they justify a decision to offset, rather than avoid, these emissions. At its July 2007 meeting, the SCB Board had a tie vote (8-8) on this issue. There are good arguments on both sides, and the issue will come up again at future  meetings. The next-biggest reduction could occur by holding the global meetings only near major airline hubs such as New York, Johannesburg, and Beijing, avoiding the fuel needed for connector flights to meeting sites like Duluth, Port Elizabeth, or Katmandu. We fully agree that offsets must be part of a more comprehensive effort that ultimately must include a transition away from fossil fuels. This will require coordinated action by all nations and industries. Thus it is appropriate that climate change is the number one priority of the new policy office that SCB established in 2007. Critics of offsets are spot-on when they argue that offsets are bad when they are used as an excuse to duck the hard decisions. But until those hard decisions are made, we insist that offsets are both real (they really do take carbon out of the atmosphere!) and good (far better than emitting carbon without any offset!). 

More importantly, 20-30% of GHG emissions come from land-use change and deforestation. Degradation of nearly a million hectares of Subtropical thicket has released vast amounts of carbon from the natural landscape’s carbon pools. We have an opportunity and obligation to return this carbon to the landscape for GHG reduction as well as all the other ecosystem services that will follow.

Does this project mean I (as an SCB member) can stop worrying about my responsibility for greenhouse gas emissions?

No! In addition to your travel to SCB meetings, you generate greenhouse gases through your household consumption, the activities of your employer, the activities of every organization to which you belong, and the activities of your local and national governments. Until you get each of these entities to offset their impacts, you are not off the hook! You may want to start with yourself: on the internet, you can find carbon calculators to estimate your footprint, and suggestions on how to reduce, replace, and restore your personal and household emissions. Each of your organizations has a board that listens to the wishes of its members – let them know you expect action. Better yet, volunteer to serve a committee to help them do so (yeah, it’s hard, but it is rewarding, and even an ecologist like me who’s forgotten the molecular weight of carbon can do it!) You can also put pressure on your employer – start with their social responsibility office if they have one. They are more responsive than you think. Indeed, large US corporations wanting to improve their images were primarily responsible for getting GW Bush to stop stonewalling on climate change. Finally, your elected representatives respond to your votes, letters, phone calls, and especially personal meetings; their staff are important too.

OK, I’m taking responsibility for my carbon footprint. I’ve “reduced” by downsizing my house, moving close to work, and trading my car for a bicycle. I’ve “replaced” dirty electricity with solar panels and installed passive solar heating in my home. To “re-store” my residual carbon emissions, can I make an annual investment in the Baviaanskloof project?

Yes, of course! For now, please donate through SCB. As soon as SCB has finalized details, you will seea link to the left that will allow you to donate to Baviaanskloof.

Can I visit the actual site where SCB dollars are restoring subtropical thicket (of course, I’ll swim and walk there to avoid emitting carbon)?

Please do! By the time you arrive, there may be a signboard to announce the location. But it is easy to find along the main east-west road through the Baviaanskloof Megareserve. If you are not walking, you’ll need a high-clearance 2WD vehicle from the east, and any 2WD from the west. The site is at the confluence of the Baviaanskloof and Kouga Rivers (see Map), about 5 km west of the delightful Rooihoek Campground. From the rise on the road northeast of the confluence, you can also see the Apieskloof canyon running towards you. Can you see the lower slopes from river level to about 50 m above river level with little vegetation? Those are the places! What, you say those lower slopes are covered with dense thicket? Hooray, it must be 2017 and the project is fabulously succeeding! For a truly low-carbon visit, use Google earth to go to  24o 23’ 24.634” E,  33o 40’ 10.014S”


Map. SCB’s restoration site is in Priority Area #5.