Southeast Asian forests: past, present, and future
Establishing a genomic library for Southeast Asian trees for biodiversity analysis, conservation, and timber authentication.
Nowhere are the challenges posed by climate change more daunting than in tropical forests, and nowhere are these challenges more pressing than in Southeast Asian (i.e. Indo-Pacific) forests. As part of the Garfield Weston-funded, Global Tree Seed Bank project, the DNA from species representing all tree genera known to occur in Southeast Asia will be sequenced for a large number of nuclear regions and their complete plastid genome. These regions will be analysed to infer evolutionary relationships, model past impacts (including climate change and other disturbances) on extant tropical forests, and improve our predictive capabilities to better inform their conservation.
A key element of Kew’s conservation work is to establish the Millennium Seed Bank (MSB) as the global repository for tree seeds: the Global Tree Seed Bank is vital in the fight to conserve the increasing number of threatened trees globally. The MSB currently holds seed from around 11,000 tree and shrub species, more than any other seed bank in the world. The establishment of the Global Tree Seed Bank has been facilitated by generous funding from the Garfield Weston Foundation which will enable a further 3,000 tree species to be banked. Given Kew’s long track record in documenting and researching the diversity of Southeast Asian trees, it is ideally placed to conduct the critically important research outlined in this project.
Why Southeast Asian forests?
Most tree species are concentrated in tropical latitudes. The Indo-Pacific region is as rich as the Neotropics, with each region harbouring about 22,000 tree species according to the latest estimates. Although tree species diversity is similar in these two regions, the level of threat they face is in sharp contrast. Southeast Asian forests have the highest deforestation rates of all tropical regions and are particularly vulnerable to disturbance (e.g. fires). In part, this is because Southeast Asian forests are understood to be in a refugial stage, i.e. ever since the Quaternary glaciations they have seen their extent and biodiversity drastically reduced.
Past, present, and future: How did we get here? Where to now?
In the face of climate change and other forms of environmental disturbance, species must adapt or go extinct. Alternatively they can shift their geographic distribution, that is, migrate to avoid habitat loss and eventual extinction. Modelling the fate of biodiversity requires an understanding of past evolutionary processes responsible for the diversity patterns observed at present. If we are to adequately assess the effects that present-day anthropogenic disturbance and climate change are having on biodiversity, it is vital we inform future models with the outcomes of past events (such as glaciations).
The information stored in genomes is a record of past history and can allow us to unravel the evolutionary processes that have resulted in extant biodiversity patterns. Traditionally, evolutionary relationships and processes have been inferred using just a few genes. Nowadays, novel high-throughput sequencing technologies, in combination with innovative computational advances, allow us to broaden the scale of our approach and improve its accuracy. The aim of this project is to provide unprecedented amounts of novel genomic data, and therefore deep insights into the past, present and future of Southeast Asian trees.
- Generate genomic data of at least one representative species of all genera of Southeast Asian trees.
- Establish a genomic reference collection with potential for use in timber authentication, trade regulation, and customs control.
- Reconstruct the phylogenetic relationships of SE Asian trees to explore patterns and timescale of diversification, and extinction using community phylogenetic metrics, correlating this with conservation status, traits (including seed traits) and environmental change data.
- Protocols and genomic data for over 1,000 genera (for the reconstruction of the plant tree of life).
- New trait-based insights into extinction risks with the aim of extending species conservation thinking and informing conservation planning.
- A reference collection of DNA sequence data of species found in the timber trade to support Kew’s authentication services.
Garfield Weston Foundation
Achard, F., Eva, H.D, Stibig, H-J., Mayaux, P., Gallego, J., Richards, T. & Malingreau, J-P. (2002)
Determination of deforestation rates of the World’s humid tropical forests
Science 297: 999–1002
Ashton, P. (2015)
On the Forests of Tropical Asia. Lest the Memory Fade
Royal Botanic Gardens, Kew
Cannon, C.H., Morley, R.J. & Bush, A.B.G. (2009)
The current refugial rainforests of Sundaland are unrepresentative of their biogeographic past and highly vulnerable to disturbance
Feeley, K.J., Rehm, E.M. & Machovina B. (2012)
The responses of tropical forest species to global climate change: acclimate, adapt, migrate or go extinct?
Frontiers of Biogeography4(2):69–84
Slik, J.W.F. et al. (2015)
An estimate of the number of tropical tree species