Accurate quantification of below-ground biomass (BGB) of woody vegetation is critical to understanding ecosystem function and potential for climate change mitigation from sequestration of biomass carbon. We compiled 2054 measurements of planted and natural individual tree and shrub biomass from across different regions of Australia (arid shrublands to tropical rainforests) to develop allometric models for prediction of BGB. We found that the relationship between BGB and stem diameter was generic, with a simple power-law model having a BGB prediction efficiency of 72-93% for four broad plant functional types: (i) shrubs and Acacia trees, (ii) multi-stemmed mallee eucalypts, (iii) other trees of relatively high wood density, and; (iv) a species of relatively low wood density, Pinus radiata D. Don. There was little improvement in accuracy of model prediction by including variables (e.g. climatic characteristics, stand age or management) in addition to stem diameter alone. We further assessed the generality of the plant functional type models across 11 contrasting stands where data from whole-plot excavation of BGB were available. The efficiency of model prediction of stand-based BGB was 93%, with a mean absolute prediction error of only 6.5%, and with no improvements In validation results when species-specific models were applied. Given the high prediction performance of the generalised models, we suggest that additional costs associated with the development of new species-specific models for estimating BGB are only warranted when gains in accuracy of stand-based predictions are justifiable, such as for a high-biomass stand comprising only one or two dominant species. However, generic models based on plant functional type should not be applied where stands are dominated by species that are unusual in their morphology and unlikely to conform to the generalised plant functional group models.
1.CSIRO Agr, GPOB 1700, Canberra, ACT 2601, Australia 2.CSIRO Land & Water, GPOB 1700, Canberra, ACT 2601, Australia 3.Univ Queensland, Sch Earth & Environm Sci, St Lucia, Qld 4072, Australia 4.Fdn Res Biodivers, Ctr Synth & Anal Biodivers, Technopole Arbois,Rue Louis Philibert, Aix En Provence, France 5.Curtin Univ, Ctr Crop & Dis Management, Dept Environm & Agr, Perth, WA 6102, Australia 6.Farm Woods, POB 385, Augusta, WA 6290, Australia 7.Murdoch Univ, Sch Environm Sci, 90 South St, Murdoch, WA 6150, Australia 8.Univ Sunshine Coast, Dept Agr & Fisheries, Sippy Downs, Qld 4556, Australia 9.Western Sydney Univ, Hawkesbury Inst Environm, Locked Bag 1797, Penrith, NSW 2751, Australia 10.CSIRO Agr, Private Bag 10, Clayton, Vic 3169, Australia 11.CSIRO Land & Water, Private Bag 10, Clayton, Vic 3169, Australia 12.CSIRO Agr, Private Bag 12, Hobart, Tas 7001, Australia 13.CSIRO Land & Water, Private Bag 12, Hobart, Tas 7001, Australia 14.Univ Sunshine Coast, Sippy Downs, Qld 4556, Australia 15.Threshold Environm Pty Ltd, POB 1124, Albany, WA 6331, Australia 16.Univ Western Australia, Ctr Excellence Nat Resource Management, 1 Foreshore House, Albany, WA 6330, Australia 17.DAFWA, 444 Albany Hwy, Albany, WA 6330, Australia 18.Dept Agr & Food Western Australia, Private Mail Bag 50, Esperance, WA 6450, Australia 19.Fares Rural Pty Ltd, POB 57, Perth, WA 6872, Australia 20.Colo Consulting, Parramatta, NSW 2777, Australia 21.CSIRO Land & Water, 47-67 Maunds Rd, Atherton, Qld 4883, Australia 22.Queensland Dept Sci Informat Technol Innovat & Ar, Mt Coot Tha Rd, Toowong, Qld 4066, Australia 23.Dept Environm Water & Nat Resources, GPOB 1047, Adelaide, SA 5001, Australia
Recommended Citation:
Paul, Keryn I.,Larmour, John,Specht, Alison,et al. Testing the generality of below-ground biomass allometry across plant functional types[J]. FOREST ECOLOGY AND MANAGEMENT,2019-01-01,432:102-114