Capitalising on a mass fruiting event to assess the long-term sustainability of rainforest remnants.

The requirement to feed a rapidly increasingly human population whilst maintaining ecosystem services and reducing biodiversity losses has led to an urgent need to design more sustainable agricultural landscapes. This is particularly relevant in SE Asia where oil palm plantations are replacing hyper-diverse tropical rainforest. Current policies for the sustainable cultivation of oil palm (an important source of edible vegetable oil) require the retention of rainforest fragments within plantations. However, the assumption that these forest fragments can continue to support high biodiversity, maintain their viability, and regenerate over time has not previously been tested. Thus one of the primary criteria for sustainability is essentially untested, and forms the basis of this proposal.

SE Asian rainforests are unique in being dominated by Dipterocarpaceae trees which reproduce irregularly (at intervals from 1 to many years) but synchronously in mass fruiting events. One of these unpredictable mass fruiting events has recently been initiated on Borneo, and provides a rare opportunity to study dipterocarp reproduction in rainforest fragments. Dipterocarp trees are a vital component of rainforest ecosystems in SE Asia, and hence any changes that affect dipterocarps are likely to have considerable knock-on impacts for rainforest biodiversity. Our recent data show an absence of dipterocarp seedlings in small forest fragments even when mature dipterocarps are present, raising a serious concern of reproductive failure of dipterocarps in fragments. The recently-initiated mass fruiting event provides us with an opportunity to explore potential mechanisms leading to reproductive failure and/or recruitment failure in forest remnants. The main objective of this project is to: (1) examine how forest fragmentation affects dipterocarp reproduction, (2) relate reproductive rates to biotic and abiotic changes arising from forest fragmentation (altered microclimates, habitat quality, predation), and (3) assess whether dipterocarp species are equally sensitive to impacts of forest fragmentation.

The proposed work will provide the first investigation of the long-term viability of forest remnants in tropical agricultural landscapes. The project will address fundamental questions about reproduction in dipterocarp trees under altered abiotic and biotic conditions, as well as producing results of considerable practical value for policy makers. It will form the basis for new research in future focussed on understanding the impacts of habitat degradation and fragmentation on biodiversity, and contribute to scientific evidence to inform the debate on developing effective conservation and sustainability strategies.

The research outputs of this project will benefit government agencies, NGOs, conservation practitioners, the oil palm industry and other agricultural commodities in SE Asia who are responsible for managing conservation in tropical agricultural landscapes. Retaining 'High conservation value' (HCV) forest within agricultural matrices is a key component of certification standards for oil palm, and the ability of dipterocarp trees to regenerate in these fragments is fundamental to determining the persistence of forest (and its associated biodiversity) within agricultural landscapes. Our project will provide crucial evidence for informing conservation strategies in SE Asia and we have planned a series of activities which will ensure that our findings are delivered to beneficiaries in an understandable and usable format.

1. Research users and their requirements
Demand for palm oil is expected to continue to increase rapidly over the forthcoming years. Oil palm plantations already put pressure on the remaining areas of undeveloped tropical forest. Thus there is an urgent need for more rigorous assessment of the effectiveness of mitigation strategies designed to limit the impacts of tropical forest modification, including retaining forest patches in plantations. Our project is designed to test whether forest patches within oil palm plantations are able to regenerate and we have a plan to develop a network of the stakeholders for knowledge exchange.

2. Methods to engage end-users for maximum impact
We will make full use of our project partners and their extensive stakeholder networks to engage end-users. The PDRA on the project (JML) has extensive experience of knowledge exchange with relevant stakeholder groups. The research team has recently established an "oil palm research-policy partnership network" of relevant stakeholders in SE Asia that we will utilise to communicate the findings of the project through workshops and "science-for-policy" report communications with funding provided for the network by the British Foreign and Commonwealth Office (see SEARRP letter of support). Members of the team regularly participate in Roundtable for Sustainable Palm Oil (RSPO) events, and this provides a platform for ensuring the findings of the project directly inform policy on conservation strategies for sustainable palm oil. We will publish the outputs of our study in peer-reviewed journals and discuss with stakeholders the most useful way of disseminating our findings of greatest relevance (e.g. reports on specific topics) and work with stakeholders to produce documents explaining the implications of these findings for biodiversity conservation, sustainable forestry and oil palm management. We intend to publicise our key findings in appropriate press outlets, via University of York press officers, and through websites such as the sustainable palm oil platform (http://www.sustainablepalmoil.org/), which is a hub for policy-relevant research outputs related to oil palm sustainability.