Sabah (Borneo)

The Sabah biodiversity experiment was established in the tropical rainforests of Southeast Asia in 2002 and a second replant took place in 2010. The experiment lies near the Royal Society's Danum Valley research station in Sabah, in the Malaysian part of Borneo. Set within a larger area of previously logged land, the station is an ideal place to study the effects of forests loss. By systematically re-growing the lost forest, scientists can determine how biodiversity is contributing to ecosystem services.

The Sabah experiment is a field-scale forest rehabilitation project and tree biodiversity experiment that looks into the effects of tree diversity on timber production, carbon sequestration, and other ecosystem processes such as erosion prevention in replanted areas. Special attention is paid to the Dipterocarpaceae family, which contains the main timber tree species of South-East Asia. Selectively logged forests in the Sabah region are usually restored using enrichment planting: seedlings of dipterocarps (and a small number of other species) are planted along cleared lines cut into the selectively logged forest vegetation.

Aerial view with plots

In the Sabah Biodiversity Experiment, the biodiversity of the enrichment-planted seedlings is manipulated. Seedlings of 16 native Dipterocarpaceae canopy tree species were planted along lines cut into the existing matrix of vegetation left over from selective logging. A total of 124 plots has been established in 2 blocks, following a randomized block design.
The core of the project is a set of 96 plots that form a gradient in enrichment-planted dipterocarp species richness. In each of the 2 blocks: a monoculture for each of the 16 study species, 16 different 4-species mixtures (2 and 4 genera), and 16 plots with all 16 species were planted. In each block, 6 control plots have not been planted.
The remaining 16 plots form a sub-experiment to look at the effects of the frequency with which climbing plants (lianas) are removed during forest restoration. These plots were also planted with all 16 species, but will receive enhanced climber cutting.

The 2 blocks with the 124 plots and the enrichment-planting lines within a plot

Site characteristics

location Sabah
former land use selectively logged production forest
altitude 102 m
soil type orthic acrisol
area 500 ha
no of plots 124
plot size 200 m x 200 m
no of trees planted c. 100 000
planting date two cohorts: 2003 and 2011
diversity variables species richness
genera richness
diversity gradient 1, 4, 16 sp.
2, 4 genera
size species pool 16 species of 5 different genera
species pool Dipterocarpus conformis, Dryobalanops lanceolata, Hopea sangal, H. ferruginea, Parashorea malaanonan, P. tomentella, Shorea johorensis, S. gibbosa, S. argentifolia, S. faguetiana, S. leprosula, S. macrophylla, S. macroptera, S. ovalis, S. parvifolia, S. beccariana
contact person Andrew Hector

The experiment is an attempt to transfer ideas and methods developed with model systems to a real-world setting. The effects of planting (planted plots vs. control plots), tree species richness (1, 4, 16 sp. planted), and frequency of liana removal on the ecosystems properties, processes, and functioning will be investigated.

Extra information
Send an e-mail to the contact person, visit the experiment's own website, or explore the publications:

  • Cesarz S, Craven D, Auge H, Bruelheide H, Castagneyrol B, Gutknecht J, Hector A, Jactel H, Koricheva J, Messier C, Muys B, Brien MJO, Paquette A, Ponette Q, Potvin C, Reich PB, Scherer-Lorenzen M, Smith AR, Verheyen K, Eisenhauer N (2022) Tree diversity effects on soil microbial biomass and respiration are context dependent across forest diversity experiments. Global Ecology and Biogeography 31:872-885 -
  • Messier C, Bauhus J, Sousa-Silva R, Auge H, Baeten L, Barsoum N, Bruelheide H, Caldwell B, Cavender-Bares J, Dhiedt E, Eisenhauer N, Ganade G, Gravel D, Guillemot J, Hall JS, Hector A, Hérault B, Jactel H, Koricheva J, Kreft H, Mereu S, Muys B, Nock CA, Paquette A, Parker JD, Perring MP, Ponette Q, Potvin C, Reich PB, Scherer-Lorenzen M, Schnabel F, Verheyen K, Weih M, Wollni M, Zemp DC (2021) For the sake of resilience and multifunctionality, let's diversify planted forests! Conservation Letters e12829 -
  • Wu J, Chen B, Reynolds G, Xie J, O'Brien M J, Liang S and Hector A (2020) Monitoring tropical forest degradation and restoration with satellite remote sensing: A test using Sabah Biodiversity Experiment. Advances in Ecological Research 62: 117-146 -
  • O'Brien M J, Philipson C D, Reynolds G, Dzulkifli D, Snaddon J L, Ong R, Hector A (2019) Positive effects of liana cutting on seedlings are reduced during El Niño-induced drought. Journal of Applied Ecology -
  • Grossman JJ, Vanhellemont M, Barsoum N, Bauhus J, Bruelheide H, Castagneyrol B, Cavender-Bares J, Eisenhauer N, Ferlian O, Gravel D, Hector A, Jactel H, Kreft H, Mereu S, Messier C, Muys B, Nock C, Paquette A, Parker J, Perring MP, Ponette Q, Reich PB, Schuldt A, Staab M, Weih M, Zemp DC, Scherer-Lorenzen M, Verheyen K (2018) Synthesis and future research directions linking tree diversity to growth, survival, and damage in a global network of tree diversity experiments. Environmental and Experimental Botany - doi: 10.1016/j.envexpbot.2017.12.015
  • O'Brien M J, Reynolds G, Ong R, Hector A (2017) Resistance of tropical seedlings to drought is mediated by neighbourhood diversity. Nature Ecology & Evolution 1: 1643-1648 - doi: 10.1038/s41559-017-0326-0
  • Granados A, Brodie J F, Bernard H, O'Brien M J (2017) Defaunation and habitat disturbance interact synergistically to alter seedling recruitment. Ecological Applications 27: 2092-2101 -
  • O'Brien M J, Ong R C, Reynolds G (2017) Intra-annual plasticity of growth mediates drought resilience over multiple years in tropical seedling communities. Global Change Biology 23: 4235-4244 -
  • Tuck SL, O'Brien MJ, Philipson CD, Saner P, Tanadini M, Dzulkifli D, Godfray HCJ, Godoong E, Nilus R, Ong RC, Schmid B, Sinun W, Snaddon JL, Snoep M, Tangki H, Tay J, Ulok P, Wai YS, Weilenmann M, Reynolds G, Hector A (2016) The value of biodiversity for the functioning of tropical forests: insurance effects during the first decade of the Sabah biodiversity experiment. Proceedings of the Royal Society B 283: 20161451 - doi: 10.1098/rspb.2016.1451
  • Brearley F Q, Saner P, Uchida A, Burslem D F R P, Hector A, Nilus R, Scholes J, Egli S (2016) Testing the importance of a common ectomycorrhizal network for dipterocarp seedling growth and survival in tropical forests of Borneo. Plant Diversity & Distributions 9: 563-576 -
  • Ang C C, O'Brien M J, Ng K K S, Lee P C, Hector A, Schmid B, Shimizu K K (2016) Genetic diversity of two tropical tree species of the Dipterocarpaceae following logging and restoration in Borneo: High genetic diversity in plots with high species diversity. Plant Ecology & Diversity 9: 459-469 -
  • Saner P, Philipson C D, Peters S, Keller F, Bigler L, Turnbull L A, Hector A (2016). Growth rates and relative change in non-structural carbohydrates of dipterocarp seedlings in response to light acclimation. Plant Ecology & Diversity 9: 491-504 -
  • O'Brien M J, Burslem D F R P, Caduff A, Tay J, Hector A (2015) Contrasting nonstructural carbohydrate dynamics of tropical tree seedlings under water deficit and variability. New Phytologist 205: 1083-1094 -
  • O'Brien M J, Leuzinger S, Philipson C D, Tay J, Hector A (2014) Drought survival of tropical tree seedlings enhanced by non-structural carbohydrate levels. Nature Climate Change 4: 710-714 -
  • Philipson C D, Dent D H, O'Brien M J, Chamagne J, Dzulkifli D, Nilus R, Philips S, Reynolds G, Saner P, Hector A (2014) A trait-based trade-off between growth and mortality: evidence from 15 tropical tree species in using size-specific relative growth rates. Ecology & Evolution 4: 3675-3688 -
  • O'Brien M J, Philipson C D, Tay J, Hector A (2013) The influence of variable rainfall frequency on germination and early growth of shade-tolerant dipterocarp seedlings in borneo. PloS One 8: e70287 - doi:10.1371/journal.pone.0070287
  • Saner P, Loh YY, Ong RC, Hector A. (2012) Carbon stocks and fluxes in tropical lowland Dipterocarp rainforests in Sabah, Malaysian Borneo. PLoS ONE, doi: 10.1371/journal.pone.0029642
  • Turnbull LA, Philipson C, Purves DW, Atkinson RL, Cunniff J, Goodenough A, Hautier Y, Houghton J, Marthews TR, Osborne CP, Paul-Victor C, Rose KE, Saner P, Taylor SH, Woodward FI, Hector A, Rees M. (2012) Plant growth rates and seed size: a re-evaluation. Ecology, 93: 1283-1289.
  • Paine C E T, Stenflo M, Philipson C, Bagchi R, Saner P, Hector A (2012) Differential growth responses in seedlings of ten species of Dipterocarpaceae to experimental shading and defoliation. Journal of Tropical Ecology 28: 377-384
  • Philipson C D, Saner P, Marthews T R, Nilus R, Reynolds G, Turnbull L A, Hector A (2011) Light-based regeneration niches: evidence from 21 Dipterocarp species using size-specific RGRs. Biotropica 44(5): 627-636 -
  • Hector A, Philipson C, Saner P, Chamagne J, Dzulkifli D, O'Brien M, Snaddon JL, Ulok P, Weilenmann M, Reynolds G, Godfray HCJ (2011) The Sabah Biodiversity Experiment: a long-term test of the role of tree diversity in restoring tropical forest structure and functioning. Philosophical Transactions of the Royal Society B 366: 3303-3315 - doi: 10.1098/rstb.2011.0094
  • Saner P, Philipson C, Ong R C, Majalap N, Egli S, Hector A (2010) Positive effects of ectomycorrhizal colonization on growth of seedlings of a tropical tree across a range of forest floor light conditions. Plant and Soil 338(1-2): 411-421 - doi:10.1007/s11104-010-0555-3
  • Hautier Y, Saner P, Philipson C, Bagchi R, Ong R C, Hector A (2010) Effects of seed predators of different body size on seed mortality in Bornean logged forest. PloS One 5(7): e11651 - doi:10.1371/journal.pone.0011651
  • Saner P, Lim R, Burla B, Ong R C, Scherer-Lorenzen M, Hector A (2009) Reduced soil respiration in gaps in logged lowland dipterocarp forests. Forest Ecology and Management 258: 2007-2012 -

Understorey inventory in one of the plots