Contents lists available at ScienceDirect Forest Ecology and Management journal homepage: www.elsevier.com/locate/foreco Allometric relationships of stem volume and stand level carbon stocks at varying stand density in Swietenia macrophylla King plantations, Bangladesh Md. Nabiul Islam Khan a,b, ⁎ , Mithun Chandra Shil a , Md. Salim Azad a,c , Md. Nazmus Sadath a,d , S.M. Feroz a , Abdus Subhan Mollick a a Forestry and Wood Technology Discipline, Khulna University, Khulna 9208, Bangladesh b Laboratory of Systems Ecology and Resource Management, Faculté des Sciences, Université Libre de Bruxelles – ULB, Campus de la Plaine, Avenue F.D. Roosevelt 50, CPI 264/1, B-1050 Bruxelles, Belgium c Graduate School of Agriculture, Kyoto University, 606-8501, Japan d Forest and Nature Conservation Policy, Georg August University, Goettingen, Germany ARTICLE INFO Keywords: Aboveground biomass Belowground biomass Mahogany Basal area Self-thinning ABSTRACT Estimation of biomass carbon per unit area of forests or woodlands is of great concern to ecologists and forest managers considering global climate change scenarios. In the framework of this study, we intend to develop allometric models to predict stem volume and stand level carbon stocks in monoculture mahogany (Swietenia macrophylla King) plantations. It was also investigated that how stand density would influence stem volume allometric equations as well as carbon stocks per unit area. Results show that the two-variable model having less than 3% mean prediction errors (MPEs) is suitable for stem volume allometric equation, and two-variable or combined-variable models having less than 2% MPEs are equally suitable for allometric equations of stand level carbon stocks. It was also found that in S. macrophylla, stem volume allometric equations are not significantly influenced by stand density. We found that mean tree carbon (kg tree -1 ) in S. macrophylla decreases at a rate of -1.58 with increasing stand density and stand level carbon stocks (Mg ha -1 ) decreases at a rate of -0.58 with increasing stand density (trees ha -1 ). The biomass carbon stocks (aboveground + belowground) in S. macro- phylla varried between 34.4 and 351.9 Mg ha -1 having a mean of 120.2 Mg ha -1 . The allometric equations of stand level carbon stocks show influence of density, which is particularly prominent in the one-variable models, in contrast to the two- or combined-variable models. High precision estimate of stand level carbon stocks can be obtained using stand basal area multiplied by mean or maximum tree height. Our work also has implications on stand density management and the use of allometric equations in estimation of stem volume and carbon stocks. 1. Introduction Gradual rise in atmospheric carbon dioxide (CO 2 ) and widespread concern about global climate change has led to interest in reducing emissions of CO 2 . It has been predicted that the average global tem- perature will increase by 2–4 °C by the year 2050 (Anderson and Bows, 2011). Combustion of fossil fuel and deforestation are the two main sources of CO 2 emission to the atmosphere (Woodwell et al., 1983; Detwiler and Hall, 1988). Climate change has been one of the major environmental issues in Bangladesh. Forestry sector is in the forefront of these issues as the country has only 2.52 million ha of forest land characterized with a high deforestation and forest degradation rate (Sadath et al., 2013). Carbon sequestration is a mechanism of capturing atmospheric CO 2 by storing it in the green plants through photosynthesis (Suwa et al., 2006; Khan et al., 2007). It has been re- cognized as a way to slow down the accumulation of CO 2 in atmosphere usually through combustion of fossil fuels. Although any living creature releases CO 2 through respiration and short living plants re-release CO 2 back to atmosphere after death and decomposition, trees however permanently store CO 2 in the form of wood in particular, thus forests serve as carbon reservoir on earth playing an important role in miti- gating global climate change (Dixon et al., 1994; Stinson and Freedman, 2001; Adame et al., 2013). Reducing Emissions from Deforestation and Forest Degradation (REDD+) is a key in recent international climate agreements and relatively cost-effective option for mitigating climate change (Gardner et al., 2012). Here, the strategic aim is to maintain terrestrial carbon storage through financial incentives or carbon pay- ments (Alongi, 2011) for forest conservation (Donato et al., 2011). https://doi.org/10.1016/j.foreco.2018.09.002 Received 23 June 2018; Received in revised form 3 September 2018; Accepted 3 September 2018 ⁎ Corresponding author at: Forestry and Wood Technology Discipline, Khulna University, Khulna 9208, Bangladesh. E-mail addresses: nabiulkhan@gmail.com, mnikhan@fwt.ku.ac.bd (Md. Nabiul Islam Khan). Forest Ecology and Management 430 (2018) 639–648 0378-1127/ © 2018 Elsevier B.V. All rights reserved. T