Nutrients and wood density in coarse root, trunk and branches in Bornean tree species

Carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) concentrations in woody tissue and bark, and wood density, were quantified for ten common Bornean tree species. The study took advantage of the ongoing logging in August 2014, sampling trees felled in the logging sites (near D Matrix, exact locations of the sampled trees not recorded). Each tree species had three replicates. The diameter of the sampled trees ranged from 12 cm to 44 cm. Sampled trees had no visible damage (e.g. no insect damage, chlorotic leaves and bent stems). The species IDs of the sampled trees were confirmed at the herbarium of the Forest Research Centre in Sepilok, Sandakan. Several points along the length of the tree were sampled: coarse root; trunk bottom, trunk middle and trunk top (highest point of the main stem); and the lowest branch of the tree, from branch bottom, branch middle and branch tip. The sampled components were cut directly after felling using a chainsaw. The samples were then transported to the chemistry laboratory of the Forest Research Centre in Sepilok, Sandakan. Bark (both the outer bark and phloem) was separated from the wood, except for the trunk top and branch tip samples, where the bark layer was too thin. Wood samples were divided into sapwood and heartwood if possible, based on a distinguishable colour difference after mechanical sanding. Sapwood and heartwood for most branch and coarse root samples were not separated due to the absence of colour boundary, but they probably consists mostly of sapwood. For chemical analyses, all samples were oven dried at 50°C to constant weight for five days and ground with a Thomas Wiley Mill to pass through a 100-mush (212-μm) sieve. Each sample was digested following the sulphuric acid-hydrogen peroxide-lithium sulphate digest procedure for vegetation described in Allen (1989). Phosphorus in the digest was determined using the molybdenum-blue method described in Anderson and Ingram (1993) and read at 880 nm on a spectrophotometer (HITACHI UV-VIS, Tokyo, Japan), while K, Ca and Mg contents were measured on an atomic absorption spectrophotometer (GBC Scientific Equipment, Victoria, Australia). Total C and N contents (as total element contents) were determined by a dry combustion method at 900°C using an Elementar Vario Max CN analyzer (Elementar Analysensysteme, Hanau, Germany). Analysis protocols are described in more detail in Majalap and Chu (1992). Wood density was quantified for trunk bottom and trunk middle samples. A strip, running through the wood disk slightly off centre, proportionally covering both sapwood and heartwood, was cut, and three (minimum of two, maximum of five, depending on the lenght of the strip) cubes (tangent ~20 mm × axial ~20 mm × radial ~20 mm length, exact dimensions recorded) were cut for wood density measurements, following the procedure ISO 3131:1975 (E) Wood -- Determination of Density for Physical and Mechanical Tests. Wood density was defined as the oven-dry mass per unit volume of fresh wood cube. Dry mass was measured after oven drying the samples at 103±2°C until the dry mass was stabilised. References: Allen, S. E. (1989). Chemical analysis of ecological materials (2nd ed.). Oxford, England; Boston; Blackwell Scientific Publications. Anderson, J. M., & Ingram, J. S. I. (1993). Tropical soil biology and fertility: a handbook of methods (2nd ed.). Wallingford, UK: C.A.B. International. Majalap, N., & Chu, N. H. (1992). Laboratory Manual for Chemical Analysis. Sandakan, Sabah, Malaysia: Forest Research Centre, Sabah Forestry Department.

Authors

• Inagawa, Takeshi — University of Oxford
• Riutta, Terhi — University of Oxford, Imperial College London
• Malhi, Yadvinder — University of Oxford
• Majalap, Noreen — Sabah Forest Research Centre
• Nilus, Reuben — Sabah Forest Research Centre
• Josue, James — Sabah Forest Research Centre

Keywords

• wood traits
• bark
• sapwood
• heartwood
• coarse root
• branch
• carbon
• nitrogen
• phosphorus
• potassium
• calcium
• magnesium
• wood specific gravity
• nutrient cycling
• wood resorption
• wood density

Funders

• Sime Darby Foundation (SAFE Core data)
• Joint Japan/World Bank Graduate Scholarship Program (JJ/WBGSP) (JJ/WBGSP)
• European Research Council Advanced Investigator Grant, GEM-TRAIT (Grant number 321131)
• NERC Human-Modified Tropical Forests Programme: Biodiversity And Land-use Impacts on tropical ecosystem function (BALI) Project (NE/K016369/1)

Permits

• Research — Sabah Biodiversity Centre (SABC) (JKM/MBS.1000-2/2 (187))

Worksheets

Files

• Inagawa_TreeComponentData_Nutrients_WoodDensity_SAFEdatabase_2023-07-10.xlsx

Taxa

32 GBIF taxa, 0 sequence-derived taxa.