Emily Fitzherbert

How will oil palm expansion affect biodiversity

Oil palm is one of the worlds most rapidly increasing crops. We assess its contribution to tropical deforestation and review its biodiversity value. Oil palm has replaced large areas of forest in Southeast Asia, but land-cover change statistics alone do not allow an assessment of where it has driven forest clearance and where it has simply followed it. Oil palm plantations support much fewer species than do forests and often also fewer than other tree crops. Further negative impacts include habitat fragmentation and pollution, including greenhouse gas emissions. With rising demand for vegetable oils and biofuels, and strong overlap between areas suitable for oil palm and those of most importance for biodiversity, substantial biodiversity losses will only be averted if future oil palm expansion is managed to avoid deforestation.

Biofuel plantations on forested lands: double jeopardy for biodiversity and climate

The growing demand for biofuels is promoting the expansion of a number of agricultural commodities, including oil palm (Elaeis guineensis). Oil-palm plantations cover over 13 million ha, primarily in Southeast Asia, where they have directly or indirectly replaced tropical rainforest. We explored the impact of the spread of oil-palm plantations on greenhouse gas emission and biodiversity. We assessed changes in carbon stocks with changing land use and compared this with the amount of fossil-fuel carbon emission avoided through its replacement by biofuel carbon. We estimated it would take between 75 and 93 years for the carbon emissions saved through use of biofuel to compensate for the carbon lost through forest conversion, depending on how the forest was cleared. If the original habitat was peatland, carbon balance would take more than 600 years. Conversely, planting oil palms on degraded grassland would lead to a net removal of carbon within 10 years. These estimates have associated uncertainty, but their magnitude and relative proportions seem credible. We carried out a meta-analysis of published faunal studies that compared forest with oil palm. We found that plantations supported species-poor communities containing few forest species. Because no published data on flora were available, we present results from our sampling of plants in oil palm and forest plots in Indonesia. Although the species richness of pteridophytes was higher in plantations, they held few forest species. Trees, lianas, epiphytic orchids, and indigenous palms were wholly absent from oil-palm plantations. The majority of individual plants and animals in oil-palm plantations belonged to a small number of generalist species of low conservation concern. As countries strive to meet obligations to reduce carbon emissions under one international agreement (Kyoto Protocol), they may not only fail to meet their obligations under another (Convention on Biological Diversity) but may actually hasten global climate change. Reducing deforestation is likely to represent a more effective climate-change mitigation strategy than converting forest for biofuel production, and it may help nations meet their international commitments to reduce biodiversity loss.

Seasonal food insecurity and perceived social support in rural Tanzania

OBJECTIVES To examine whether the occurrence of seasonal food insecurity was related to ethnicity, household wealth and perceived social support, and to assess whether social support was more efficacious in protecting against food insecurity in wealthier households. Secondary objectives were to assess the association between past food insecurity, current dietary intake and perceived health. DESIGN, SETTING AND SUBJECTS A sample of 208 randomly selected mothers from two ethnic groups living in the same villages in rural Tanzania participated in a cross-sectional survey. RESULTS Food insecurity was highly prevalent in this area, particularly among the poorer ethnic group. Half of ethnically Sukuma households fell into the most food-secure category, compared with only 20% of ethnically Pimbwe households. Among both groups, measures of household wealth and social support were strongly associated with food security. Interestingly, social support appeared to be more effective among the wealthier ethnic group/community. Past food insecurity was also related to current indicators of dietary intake and womens self-perceptions of health. CONCLUSION Greater social support is associated with food security, suggesting that it may protect against the occurrence of seasonal food insecurity. Social support also interacts with wealth to offer greater protection against food insecurity, suggesting that increasing wealth at the community level may influence food insecurity through both direct and indirect means. Seasonal food insecurity also appears to have lasting effects that likely create and reinforce poverty.

Conservation Value of Multiple-Use Areas in East Africa

Despite wide agreement that strictly protected areas (World Conservation Union categories I-III) are the best strategy for conserving biodiversity, they are limited in extent and exclude many species of key conservation importance. In contrast, multiple-use management areas (categories IV-VI), comprising >60% of the worlds protected-area network, are often considered of little value to biodiversity conservation, particularly in Africa, where they typically contain few charismatic large mammals. We sampled small mammals, amphibians, birds, butterflies, and trees at 41 sites along a four-step gradient of increasing human activity and decreasing conservation protection, from a well-protected Tanzanian national park to nonintensive agricultural land. Although preliminary, our results indicate that species richness of these five taxa did not decline along this gradient, but different management areas, occupying areas of largely similar habitat, hosted distinct communities of each taxon. Differences in species composition in the absence of manifest differences in species richness highlight the importance of developing landscape-scale conservation strategies and the danger of using either a limited suite of indicator taxa or umbrella species as surrogates for biodiversity. Although strictly protected areas perform a unique and vital conservation service in East Africa by protecting large mammals, areas that allow varied resource extraction activities still possess vital and complementary conservation value.

Tigers, markets and palm oil: market potential for conservation

AbstractIncreasing demand for cooking oil and biofuels has made palm oil, > 80% of which is grown in South-east Asia, the dominant globally traded vegetable oil. However, this region is host to some of the world?s most biodiverse and threatened tropical forests. Strategic engagement with commercial operations is increasingly recognized to be an essential part of the solution for raising funds for conservation initiatives, raising consumer consciousness and potentially stemming environmental degradation. Linking market incentives towards conservation is also of critical importance because it is becoming widely recognized that conservation needs to begin to address the wider countryside (outside protected areas) where human?wildlife interactions are frequent and impacts are large. Using the Sumatran tiger Panthera tigris sumatraeas both a threatened species in its own right and emblematic for wider species diversity, we show that western consumers are willing to pay a significant premium for products using palm oil grown in a manner that reduces impacts on such species. Results suggest that the price premium associated with a ?tiger-friendly? accreditation may provide a useful additional tool to raise conservation funds and, within the right institutional context, serve as an inducement to address the problem of habitat and species loss.

Conservation in oil-palm landscapes

A recent letter proposes managing oil-palm (Elaeis guineensis) plantations as agroforestry systems, to reduce biodiversity impacts (Bhagwat & Willis 2008). We suggest that conservation efforts should continue to focus instead on preventing deforestation, even if this necessitates monospecific plantations. Our arguments are based on evidence that (1) agroforestry is not a viable outlet for the economic forces driving oil-palm expansion, (2) oil palm is an unsuitable candidate for high-yield agroforestry, and (3) a biodiversity-yield trade-off is likely, such that high-yield systems will have low biodiversity and low-yield systems will conserve far fewer species than natural forests and require more area (read forest clearance) to meet any level of demand for palm oil. Oil-palm expansion is driven by large companies and smallholders responding to global demand for palm oil (Fitzherbert et al. 2008). Prices are expected to remain high, which will continue to provide an incentive for the conversion of less-productive landcovers. Low-yield systems are simply not competitive. Oil-palm yields are very low when they are shaded by other trees because of competition for light and nutrients (Corley & Tinker 2003). Furthermore, harvesting of fruits is inefficient where palms are widely spaced and where dense understory vegetation is permitted to develop. Where the aim of smallholders is to produce palm oil, agroforestry is typically replaced by monospecific systems. Systems where crops such as cassava (Manihot esculenta) are intercropped with immature oil palms can be described as agroforestry, but provide no appreciable biodiversity benefits (Cheyns & Rafflegeau 2005). The conservation value of croplands depends on whether they can support enough biodiversity to compensate for the greater area they occupy relative to the highest yield option (Green et al. 2005). Increasing the biodiversity value of oil palm sufficiently is likely to involve too large a yield penalty. The term agroforestry encompasses a wide range of agronomic systems, from low yield to high yield and from biodiversity rich to biodiversity poor, and therefore there should be no assumption that it is necessarily good for biodiversity. Best are complex agroforests with native understory and noncrop species of canopy trees (Schroth et al. 2004). In these systems competition can be expected to cause lower yields than from less diverse systems, whose biomass is dominated by crop plants. Indeed, growing oil palm under canopy trees results in low yields, and even then is unlikely to provide habitat for many of the species of most conservation concern (Scales & Marsden 2008). Bhagwat and Willis argue that agroforestry can act as a benign matrix for species dispersal. For many species, persistence might be better enhanced by enlarging or maintaining areas of natural forest while intensifying production on converted land rather than encouraging agroforestry that would require more forest clearance for any palm-oil production target. Neither is it clear that oil-palm– based agroforestry will be a better poverty reduction tool than monospecific plantations. A better solution could be coordination of development and conservation efforts. Alongside efforts by conservation organizations to conserve forests, development organizations could work to improve smallholders’ abilities to enhance yields, find employment, and escape poverty through better access to credit, improved planting material, fertilizers, information, and markets (Cheyns & Rafflegeau 2005). What other solutions do we suggest? Protecting natural forests remains the best hope for biodiversity in new and established regions of oil-palm cultivation (Koh & Wilcove 2008). In our opinion conservation organizations in tropical forest countries are correct to focus their resources primarily on forest protection: improving the effectiveness of existing reserves, developing new approaches, such as conservation concessions, and reducing the impacts of logging. Palm-oil producers can help by adhering to the Principles and Criteria of the Roundtable on Sustainable Palm Oil (RSPO 2007), especially by avoiding the conversion of forests, including remnants, that can have substantial biodiversity value and provide pest-control benefits (Koh 2008). If forests were better protected, palm-oil demand could be met by maximizing yields on unforested land. This does not preclude efforts by producers to reduce pollution, encourage native plants, and raise