Sabah (Borneo)

The Sabah biodiversity experiment was established in the tropical rainforests of Southeast Asia 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:

  • 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 (in press) 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, 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
  • 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
  • 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

Understorey inventory in one of the plots