Establishing the evidence base for maintaining biodiversity and ecosystem function in the oil palm landscapes of South East Asia

Abstract

The conversion of natural forest to oil palm plantation is a major current threat to the conservation of biodiversity in South East Asia. Most animal taxa decrease in both species richness and abundance on conversion of forest to oil palm, and there is usually a severe loss of forest species. The extent of loss varies significantly across both different taxa and different microhabitats within the oil palm habitat. The principal driver of this loss in diversity is probably the biological and physical simplification of the habitat, but there is little direct evidence for this. The conservation of forest species requires the preservation of large reserves of intact forest, but we must not lose sight of the importance of conserving biodiversity and ecosystem processes within the oil palm habitat itself. We urgently need to carry out research that will establish whether maintaining diversity supports economically and ecologically important processes. There is some evidence that both landscape and local complexity can have positive impacts on biodiversity in the oil palm habitat. By intelligent manipulation of habitat complexity, it could be possible to enhance not only the number of species that can live in oil palm plantations but also their contribution to the healthy functioning of this exceptionally important and widespread landscape.

Functional structure of ant and termite assemblages in old growth forest, logged forest and oil palm plantation in Malaysian Borneo

“…The consistently strong negative response of all termite groups, may lead to a decline in decomposition rates. The only study to consider this to date (Foster et al 2011), shows that leaf litter breakdown remains constant along a similar habitat disturbance gradient, and thus does not support this hypothesis. However, leaf litter may not be representative of the functioning of the whole system, because termites feed on a range of organic material, and leaves may only be a small part of that system (Eggleton et al 1997).…”

“…Furthermore, leaf litter is consumed by a wide range of other invertebrates. In addition, the majority of decomposition in oil palm plantations is conducted by only a single termite species (Macrotermes gilvus) (Foster et al 2011) indicating low levels of functional redundancy, and high vulnerability of ecosystem functioning to species loss.…”

Conclusion: applying South East Asia Rainforest Research Programme science to land-use management policy and practice in a changing landscape and climate

“…The SAFE Project thus involves and potentially integrates the breadth of science covered by SEARRP and directly addresses some of the key needs identified by Foster et al [10] regarding the ecosystem functioning of part-forest, part-oil palm landscapes (see above). In their article on the Sabah Biodiversity Experiment, Hector et al [12], by comparing a regenerating forest 22 years after selective logging with primary forest, demonstrate the scale of total carbon gain (100 tonnes of carbon per hectare or 40% of primary rainforest values) and biodiversity and other ecosystem services that could be obtained if enrichment planting is employed.…”

“…This means that there may be advantages from the point of view of regional biodiversity of having a larger number of small fragments within oil palm landscapes rather than a small number of larger fragments, though the long-term viability of small fragments in terms of ecological functioning is questionable and remains untested. Foster et al [10] quantify for different taxa the substantial losses in species richness associated with oil palm conversion, but they also explore how local and landscape complexity might not only enhance biodiversity within a part-forest, part-oil palm landscape, but also support ecosystem functioning and ecosystem services within such landscapes. They argue that ecologists first need to provide robust scientific evidence for this and then use such evidence to persuade policy-makers and the palm oil industry to design and adopt oil palm landscapes that will function in a healthier and more sustainable way.…”

Management of Legume as Land Cover Crop and Empty Bunch for the Nitrogen Efficiency in Inceptisols at Oil-Palm Plantation

“…Indonesia and Malaysia are the largest producers, and oil palm cultivation is rapidly expanding in areas such as Thailand, Nigeria and Colombia. Palm oil is the most widely used vegetable oil in the world and of huge importance as a biofuel feedstock (William et al 2011).…”