Forest Research
We study the botanical composition, structure and dynamics of the forest through a number of ongoing research projects. A total 317 species of plant have been identified in the Sabangau Forest, of which 222 are trees, and samples of leaves, flowers and fruits have been collected for storage at the CIMTROP Herbarium. Each species has been assigned both a Latin name and a variety of local names from different areas. In this way we have built up a comprehensive inventory of peat-swamp forest botanical composition and this inventory is used as a baseline to support other research projects, including studies of primate feeding ecology and behaviour; forest regeneration, succession and restoration; and assessing biodiversity at remote monitoring sites.
We have established six 0.4 ha permanent tree plots within the Natural Laboratory, set up along a gradient of increasing peat depth. Each plot is divided into two sub-plots: the first measuring 0.15 ha in area, with all trees greater than 6 cm diameter at breast height (dbh) tagged; and the second measuring 0.25 ha in area, with all trees greater than 20 cm dbh tagged. In both sub-plots all lianas and figs greater than 3 cm diameter that are rooted in the plot are tagged. These plots were established in 2001 and measurements of dbh and basal area are made biennally in odd-numbered years. These data are used to identify changes in biomass, size-distributions, tree density and species composition over time, identify species growth and mortality rates, and address other forestry questions. Overall, they demonstrate an increase in biomass since the cessation of illegal logging.
These same plots are also monitored for reproductive phenology. Around 2,400 trees are checked each month to record whether they have immature fruits, mature fruits, flower buds, open flowers, young leaves or none of the above. These data are used by the primate behaviour researchers to compare with primate activity and feeding patterns, reproduction and other behavioural variables; identify times for fruit collection by the Nursery Project; and answer questions on tree reproductive behaviour, synchronicity, dispersal, development and growth. We also address forest productivity through the use of forty 1 m square litterfall traps set up inside the forest and in the restoration zone. All vegetative parts that fall into the traps are collected, dried, separated into type and weighed twice a month. Data collected since 2005 show huge peaks in litterfall during periods of intense haze from forest fires, indicating great stress experienced by trees at these times.
We study natural regeneration and succession resulting from a variety of different disturbance types by measuring tree, sapling and seedling growth in fixed plots. These plots have been set up perpendicular to illegal logging canals, logging skids and logging railways, as well as in undisturbed forest and burnt forest, and are re-measured every two years to provide a long-term record of regeneration.
We have established six 0.4 ha permanent tree plots within the Natural Laboratory, set up along a gradient of increasing peat depth. Each plot is divided into two sub-plots: the first measuring 0.15 ha in area, with all trees greater than 6 cm diameter at breast height (dbh) tagged; and the second measuring 0.25 ha in area, with all trees greater than 20 cm dbh tagged. In both sub-plots all lianas and figs greater than 3 cm diameter that are rooted in the plot are tagged. These plots were established in 2001 and measurements of dbh and basal area are made biennally in odd-numbered years. These data are used to identify changes in biomass, size-distributions, tree density and species composition over time, identify species growth and mortality rates, and address other forestry questions. Overall, they demonstrate an increase in biomass since the cessation of illegal logging.
These same plots are also monitored for reproductive phenology. Around 2,400 trees are checked each month to record whether they have immature fruits, mature fruits, flower buds, open flowers, young leaves or none of the above. These data are used by the primate behaviour researchers to compare with primate activity and feeding patterns, reproduction and other behavioural variables; identify times for fruit collection by the Nursery Project; and answer questions on tree reproductive behaviour, synchronicity, dispersal, development and growth. We also address forest productivity through the use of forty 1 m square litterfall traps set up inside the forest and in the restoration zone. All vegetative parts that fall into the traps are collected, dried, separated into type and weighed twice a month. Data collected since 2005 show huge peaks in litterfall during periods of intense haze from forest fires, indicating great stress experienced by trees at these times.
We study natural regeneration and succession resulting from a variety of different disturbance types by measuring tree, sapling and seedling growth in fixed plots. These plots have been set up perpendicular to illegal logging canals, logging skids and logging railways, as well as in undisturbed forest and burnt forest, and are re-measured every two years to provide a long-term record of regeneration.
