Allometric Models to Estimate Carbon Content in Arecaceae Based on Seven Species of Neotropical Palms

Abstract

Abstract We present allometric models to estimate total carbon content and above ground carbon (AGC) for the family Arecaceae, and for 7 abundant neotropical palm species (the canopy species Socratea exorrhiza and Iriartea deltoidea , the sub-canopy palm Euterpe precatoria , and the understory species Asterogyne martiana , Prestoea decurrens , Geonoma interrupta and Chamaedorea tepejilote ). The study was done in the tropical rainforests of the Caribbean slope of Costa Rica. We harvested 87 individuals of a wide range of sizes, and divided them into roots, stems, and leaves, weight their fresh and dry biomass, calculated the carbon content, tissue density, leaf area, and shoot:root ratios (based on biomass and carbon content). The general palm model estimating total carbon content accounted for 92% of the variation and had diameter at breast height, stem height, and dry mass fraction as predictor variables. We generated a similar model to estimate AGC, which included the same variables and explained 91% of the variation. We compared our AGC model with two models used to estimate palm carbon content: Goldman et al. (2013)´s and Chave et al. (2014)´s models and found a range of R 2 values ​​of 0.87 to 0.91. Understory palm allometry was centered around biomass allocation, whereas sub-canopy and canopy species were associated with traits related to palm size (mainly DBH, total height, and leaf area). The efficiency the allometric models depends on species identity, sample size, and size range.