Allometric models for biomass, nutrients and carbon stock in Excoecaria agallocha of the Sundarbans, Bangladesh

Abstract

Allometric relationships between easily measurable independent variables like diameter at breast height (DBH) and total height (TH) and biomass of leaf, branch, bark, stem without bark, and total above-ground biomass of Excoecaria agallocha L. were tested. Similarly, relationships between independent variables (DBH and HT); and nutrients (N, P and K) and carbon content in total above-ground biomass were also evaluated. The best fit allometric models were selected by considering the values of parameter of estimation of the models such as R2, CV, Rmse, MSerror, Sa, S, and Akaike’s information criterion corrected (AICc). The selected allometric models were Log Biomass = 0.9256 Log DBH2- 2.133; Log biomass = 1.1656 Log DBH2- 1.7047;Log biomass = 1.0824 Log DBH2 biomass = 1.0927 Log DBH2- 1.7568; Log - 1.0275; Log biomass = 1.0996 Log DBH2- 0.8572 respectively for eaf, branch, bark, stem without bark and total aboveground biomass. Whereas the selected allometric models for nitrogen, phosphorus, potassium and carbon were Log N = 1.0972 Log DBH2- 3.0845; Log P = 1.0947 Log DBH2- 5.6790; Log K =1.0990 Log DBH2- 3.0370; Log C = 1.1 Log DBH2- 1.1937 respectively. Highest concentration of nitrogen (16.07 mg/g) and phosphorus (0.05 mg/g) was observed in leaf, while higher concentration (45.95–48.60 %) of carbon was observed in stem and bigger branches. The findings of this study are firsthand information for forest managers and conservation workers for sustainable management of E. agallocha in the Sundarbans of Bangladesh. Keywords Allometry _ Biomass _ Carbon _ Excoecaria agalloch _ Nutrients _ Sundarbans