In Search for the Silver Bullet: Mitigating Climate Change through Oil-Palm Agroforestry

By Baruani Mshale

This investigative review compares oil palm agroforestry, monoculture oil-palm and soybean oil production using four parameters: biodiesel production, carbon sequestration, food security and biodiversity conservation. Oil-palm agroforestry promises multiple benefits including: displacing petrodiesel use; requires ten-times less land area compared to soybean; positively affect local food security; has no carbon debt; and result to significantly less effects on biodiversity conservation. Oil-palm agroforestry’s positive impacts are largely due to its need for a significantly smaller land area and the combination of palm-trees and food crops on the same land. This article further emphasizes that impacts of biofuel production depend on several factors such as choice of biofuel feedstock, history of land use, location of biofuel feedstock plantation and cultivation systems. Therefore using case studies to generalize at the global level might be flawed. Local level silver bullets are already there, but searching for a global silver bullet might be detrimental to the whole process.


There is a growing consensus among nations that in order to avoid dangerous anthropogenic interference of the climate system, there is an urgent need to reduce both emissions and concentrations of GHGs in the atmosphere (IPCC, 2007; Stern Review, 2007). Much of the GHG emissions over the past 150 years are a result of human activities in pursuit of economic development (IPCC, 2007; Stern Review, 2007). Implementing mitigation actions is costly and if there are no regulations or incentives to limit emissions, it is likely that no reduction in emissions will be achieved (Stern Review, 2007). The search is still on in finding the best approach that will yield greater economic returns and achieve environmental goals sustainably. The world is searching for a “silver bullet”.

A famous economist – Tinbergen – shared Nobel Prize Award in 1969 for his work on economic policy that can be summarized as “one stone can not kill two birds” meaning that a single policy can not achieve two or more clearly separate goals. Yet, present-day decision makers at various levels are arguing for win-win policy strategies in the climate change issue. For instance the UN REDD program became “REDD + +” with the additional two-plus-signs representing biodiversity conservation and improving livelihoods, respectively ( This makes one wonder: Are present-time policy makers ignoring or want to disprove Tinbergen’s rule? Is there a silver bullet for the climate issue? Is this silver bullet at the local or international level? Is it even worth trying to find a silver bullet? This article provides some insights into these questions using the case of oil-palm agroforestry in the Rufiji River delta in Tanzania (1).

Making the case for oil-palm agroforestry

Agroforestry is defined as “a collective name for land-use systems and technologies, where woody perennials (trees, shrubs, palms, bamboos, etc.) are deliberately used on the same land management unit as agricultural crops and/or animals, either in some form of spatial arrangement or temporal sequence” (ICRAF, 1993). Oil-palm agroforestry combines food crop farming and palm-oil trees on the same land.

The African Green Oil Limited has applied for a land-lease to the Tanzania Investment Center (TIC) for more than 10,000 hectares of land in the Rufiji river delta in south-east Tanzania for oil-palm plantation. TIC has the role of overseeing that all investments in the country contribute to rural development. African Green Oil Limited has been granted a land lease for 250 hectares as a trial investment and the area will be increased depending on their performance. The company aims at producing palm-oil for sell to different buyers including biofuel producers.

Company owners use mechanized tillage and plant palm trees and then allow local people to plant food crops in between palm trees. Land tilling is the most time and money consuming farming activity among local farmers, therefore aims at making farming easier to farmers. In this arrangement, local people are expected to abandon their current food-crop farms. Furthermore the company promised and has already employed a few local people in its various activities. From its investment returns, the company plans to contribute in improving social services such as building schools, road construction and health centers. Local people in the seven villages neighboring the company’s plantation cultivate cashew-nuts as their main cash crop. Therefore, local farmers are expected to have more time and resources to work on their cashew plantations since they will not spend time and resources tilling land for food crop farming. Therefore cashew-nut yields are expected to increase and therefore increase locals’ income. Such an arrangement promises benefits spanning from local to global level and from environmental to socio-economic benefits. If this arrangement succeeds, will it imply that oil-palm agroforestry was that silver-bullet being searched for? Can findings from this particular project be applied elsewhere?

Benefits of the oil-palm agroforestry in the Rufiji River delta
This article compares the production of biodiesel from monoculture oil-palm, oil-palm agroforestry and soybean plantations. I use four parameters in the comparison including biodiesel yield, carbon sequestration/emissions, food production and biodiversity conservation.

Bio-diesel production:

Palm-oil can be used to produce bio-diesel and is already available commercially. Table 1 shows that, although current soybean plantation area is about ten-times larger than area under oil-palm plantation, the two feedstock crops produce about the same total amount of global oil (Barison, 2007). This is because oil-palm has higher oil productivity than soybean (Table 1) at 3.68 tons/ha/yr compared to 0.36 tons/ha/yr, respectively. Using information from table 1, reveal that, the 92.10 million hectares under soybean plantation would have produced 338.93 million tones of oil if they were under palm oil plantations but only produced 33.16 million tones of soybean oil.


In terms of revenues, prices for oil-palm and soybean oil are not very different, trading at US $ 790 and $ 840 per ton, respectively (The Daily Star, 04/17/09). If all soybean plantations were converted to oil-palm plantations, revenue gains would increase by around ten times. Furthermore, while establishment costs for both feedstocks are not very different because they involve clearing almost the same types of tropical rainforests, over time maintenance costs will significantly decrease for oil-palm compared to soybean since there is no annual replanting costs for palm-oil because palm trees are perennial. Therefore, significant revenues are missed out when cultivating soybeans as compared to oil-palm.

Carbon sequestration:

Oil-palm agroforestry is likely to have a net sequestration effect. Palm-oil trees are perennial woody trees while soybeans are herbaceous annual crops. Over time palm-oil plantations sequester significantly more carbon than soybean plantations. Fargione et al. (2008) calculated a per hectare carbon debt for different biofuels that shows no significant different between soybean and oil-palm carbon debts: 737 Mg CO2/ha and 702 Mg CO2/ha, respectively. This is misleading because it does not include how much land has already been converted to each biofuel feedstock plantation. This article expands on Fargione et al.’s analysis by calculating aggregate carbon debt using current total land area under each of the two feedstocks. Soybean plantations are ten times in size compared to oil-palm plantations (Table 1).

Using Fargione et al.’s per hectare carbon debts to calculate total historical carbon debt for the two crops. Each per hectare carbon debt is multiplied by the total land area under each crop (table 1).

Soybean: 737 Mg CO2/ha x 92.10 million hectares = 67,877.7 million Mg CO2
Oil palm: 720 Mg CO2/ha x 9.17 million hectares = 6,437.34 million Mg CO2

Therefore in producing the same amount of oil (table 1), soybean has incurred a carbon debt that is ten times more than that of oil-palm.

Aggregating Fargione et al.’s repayment rates by factoring-in total land converted for each of the two oil crops plantations gives aggregate annual repayment rates of:

Soybean: repayment rate 0.9 Mg CO2/ha/yr X 92.10 million ha = 82.89 million Mg CO2/yr
Oilpalm: repayment rate 7.1 Mg CO2/ha/yr X 9.2 million ha = 65.32 million Mg CO2/yr

Using the above total historical carbon debt and aggregate annual repayment rates to calculate repayment period gives:

Soybean: 67,877.7 million Mg CO2 divided by 82.89 million Mg CO2/yr = 818 years
Oilpalm: 6,437.34 million Mg CO2 divided by 65.32 million Mg CO2/yr = 99 years

This article concludes that it will take 818 years for soybean to repay its total historical carbon debt while it will take 99 years for oilpalm to repay its total historical carbon debt. This analysis improves on Fargione et al.’s calculations by considering how much land is currently under each of the two major crops. This correction matters because the land under soybean plantations globally is ten times larger than oilpalm plantations. Calculating repayment period without considering how much land has already been converted to each crop’s plantation underestimates the repayment time.

Adopting Fargione et al.’s methods for calculating the carbon debt, this article finds that oil-palm agroforestry have no carbon debt. This is because the soil and vegetation carbon emitted when converting coastal forests to oil-palm agro-forestry will be offset in reforesting abandoned croplands when local farmers abandon their food crop farms and plant food crops in between palm trees under agroforestry practices.

Food production:

Biofuel production partly account for recent regional and global food shortages in various ways: through competing for resources with food production such as water, land, capital and agricultural labor; food-crop biofuel feedstocks such as corn reduced amount of food available for human consumption; and price increase of food-crop feedstocks made it expensive for the world’s poor to compete with richer biofuel feedstock buyers (FAO, 2008). However, in the Rufiji River delta, a different experience is reported or expected. Oil-palm agroforestry combines palm trees and food crops farming thus not affecting food productivity. Even more, company owners till the land and allow farmers to plant their food crops in between palm trees. In this way farmers can plant larger areas compared to their traditional farming practices since they are no longer incurring the cost and time for tilling their own farms. Therefore food productivity is likely to increase ensuring food security.

Biodiversity conservation:

Conversion of tropical rainforests for monoculture biofuel feedstock cultivation results into loss of important habitats for tropical biodiversity (Casson, 2003). Compared to oil-palm, the loss of critical habitats due to soybean plantations has been ten times that of oil palm since soybean requires ten times more land to produce the same amount of oil as oil-palm. Oil-palm agroforestry in the Rufiji River delta promises even more positive impacts on biodiversity conservation. Abandoned croplands by local farmers will be left to reforest and therefore provide habitats for coastal forest biodiversity. Furthermore, since about 90% of coastal forests in Tanzania had already been cleared due to illegal logging and charcoal production, oil-palm agroforestry will not result to massive loss of critical habitats compared to habitat loss in Malaysia, Indonesia and Brazil.

Other benefits:

Reforestation in the abandoned crop lands can provide important non-timber forest products that sustain local livelihoods. Furthermore, reforested abandoned cropland can participate in the clean development mechanism (CDM) as aforestation projects and therefore providing locals with additional revenues from the sell of carbon credits. However the decision by local farmers to abandon their traditional crop-lands is not influenced by prospects of economic returns only, some people have cultural and historical attachment to their farmlands such that they may not participate in this arrangement.

Table 2 below summarizes the above impacts of the two feedstock crops and farming systems.



Oil-palm agroforestry has the potential of sequestering atmospheric CO2, increase food production, contribute in avoiding loss of biodiversity, and reduce CO2 emissions by displacing fossil fuels. If all area under soybean was converted to oil-palm agroforestry plantation, revenues would have increased ten times and there will be no carbon debt. Some of these benefits are local while others are global. Caution should be taken when using these findings to argue for or against oil-palm agroforestry since this is a very context specific case of oil palm-agroforestry. This article further emphasizes that impacts of biofuel production depend on several factors such as choice of biofuel feedstock, history of land use, location of biofuel feedstock plantation and cultivation systems.

Is Tinbergen wrong? The obsession with policy makers in trying to find the silver bullet solution to development and environmental challenges at the global level may be detrimental to the whole process. Whereas palm-oil production in Malaysia has resulted to serious loss of biodiversity and increased GHG emissions, the same biofuel feedstock have very different impacts in the Rufiji river delta in Tanzania. Therefore using either of the two cases to argue for a global position on oil-palm production will be wrong. Silver bullet solutions may exist at very local scales and in very specific contexts. These local level solutions should be encouraged where they work but should not be used for generalization. Tinbergen might be right that we can not find that “global silver bullet” but he might be wrong since there is evidence of “local silver bullets.”

(1) I participated as the lead research assistant in a feasibility study on large scale biofuel production in Tanzania. This study was conducted between June and September 2009. The study assessed the feasibility from an interdisciplinary perspective whereby the team included researchers from three universities in Tanzania and over seven disciplines such as law, economics, engineering, chemical engineering, marketing, forestry, urban planning, environment and agriculture. The Rufiji River delta area was one of the areas studied. Several biofuel feedstock crops were analyzed including oil-palm, sugarcane, and jatropha. More information about the study is available at


Basiron, J. 2007. Palm oil production through sustainable plantations. Eur. J. Lipid Science and Technology Vol. No 107: 289-295

Casson, A. 2003. Oil Palms, Soybeans and Critical Habitat Loss. A Review Prepared for the WWF Forest Conversion Initiative available at accessed on 04/16/2009

Fargione, J., J. Hill, D. Tilman, S. Polasky, and P. Hawthorne. 2008 Land clearing and the biofuel carbon debt. Science 319:1235-1238.

ICRAF, 1993. International Centre for Research in Agroforestry: Annual Report 1993. Nairobi, Kenya. pp 208.

IPCC, 2007: Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [B. Metz, O.R. Davidson, P.R. Bosch, R. Dave, L.A. Meyer (eds)], Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Available online:

J. Tinbergen, On the Theory of Economic Policy. Amsterdam: North Holland, 1952

Nicholas Stern. The Economics of Climate Change: The Stern Review. Cambridge University Press 2007 available online at

Oil World Annual Report 2008 available at

“Edible Oil Prices Rise Again” The Daily Star Newspaper of April 17, 2009 available at accessed on 04/17/09

“The State of Food and Agriculture, 2008. Biofuels: prospects, risks and opportunities” Food and Agriculture Organization of the United Nations, Rome, 2008. Available at Accessed on 04/16/09


4 Responses so far »

  1. 1

    mrred said,

    Love this blog I’ll be back when I have more time.

  2. 2

    Hi! Really good information, I have bookmarked your site, perhaps you would like to take a look at as we have some information you may find usefull in the members area – Keep up the Good Work!

  3. 3

    Ben Phalan said,

    This article, and especially table 2, is nonsense. Taking oil palm agroforestry vs. oil palm monoculture with similar overall yields, there is just as much likelihood that one will replace habitats important for biodiversity as another. Whether or not either system results in net carbon emissions and biodiversity loss depends heavily on what land use is replaced (forest? wetland? abandoned farmland?), not whether the palm trees are underplanted with cassava or not.

    Oil palm agroforestry is not eligible for CDM credits, and NTFP provision would likely be as high in monoculture as in a system with integrated annuals.

    It seems unlikely that oil yields per hectare would be as high in a mixed system as in a monoculture; if it was to be the case, the food crop yields would likely be low as you’d need to avoid planting close the root zone of each palm, and the crops would also be shaded.

    In conclusion, Tinbergen was more right than you think!

  4. 4

    Great news posts here. But it will be a great honour for me if you can spend just a little of your valuable times to give a comment on my Indonesia-news Blog.
    thanks alot

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