Large contribution of recent photosynthate to soil respiration in tropical dipterocarp forest revealed by girdling

The research site is one of the existing intensive carbon plots (Tower Plot) at the SAFE Project Experimental area. The area where the plot is located will be converted into oil palm plantation during 2015-2017 (for commercial purposes, not for research). The overarching aim of the project is to assess how the termination of the transport of sugars and defoliation alter forest ecosystem functioning and structure.The aim of the project is: 1. To quantify the contribution of photosynthate supply to soil respiration: via the contribution of roots and soil microbial communities utilising root-derived carbon. 2. To assess whether there is a relationship between root respiration and tree species. To address these aims, we girdled trees in one half of the plot (0.5 ha), leaving the other half (0.5 ha) as a control. In girdling, a strip of bark (including cambium and phloem) was removed from around the trunk, with the aim of stopping the transport of sugars from the foliage into the roots and soil. The transport of sugars stop immediately, allowing us to quantify their role in the root and soil processes. The girdled trees will gradually defoliate and die due to the carbon starvation of the roots. We wish to emphasise that these trees would have been felled anyway during the conversion to oil palm - this project is not causing any additional deforestation. The processes measured are: - CO2 fluxes from soil measured with portable chambers from which a gas sample is drawn and analysed in the field with a portable instrument (CO2) - Changes in tree circumference monitored with automatic dendrometer bands. - Terrestrial laser scanning (T-lidar), non-destructive method to quantify the 3D structure of the forest stand.Pre-girdling data of all processes will be collected, starting at least two months before the girdling. The girdling took place in early 2016, and the monitoring continued for twelve months afterwards.

Authors

• Nottingham, Andrew — University of Edinburgh, University of Leeds
• Cheeseman, Alexander — James Cook University, Universtiy of Exeter
• Riutta, Terhi — University of Oxford, Imperial College London
• Doughty, Christopher — Northern Arizona University
• Telford, Elizabeth — University of Edinburgh
• Huasco, Walter Huaraca — University of Oxford
• Svátek, Martin — Mendel University
• Kvasnica, Jakub — Mendel Universtiy
• Majalap, Noreen — Forest Research Centre
• Malhi, Yadvinder — University of Oxford
• Meir, Patrick — University of Edinburgh, Australian National University
• Teh, Yit Arn — Newcastle University

Keywords

• Girdling
• Licor
• Carbon
• Tree
• Mortality

Funders

• NERC, the Ministry of Education, Youth and Sports of the Czech Republic (NE/K01627X/1, NE/G018278/1, INTER-TRANSFER LTT19018)

Permits

• Research — Sabah Biodiversity Council (JKM/MBS.1000-2/2 JLD.4 (3))

Worksheets

Files

• BALI_Nottingham_Girdling_Data_2021_rev.xlsx

Taxa

108 GBIF taxa, 0 sequence-derived taxa.