Estimation of the dry leaf biomass of Lippia graveolens Kunth in southeastern Coahuila

Abstract

Oregano is a non-timber forest resource of commercial importance, considered as a culinary and aromatic species that is used in the semi-arid areas of Coahuila, with a yield of more than 700 t per year and representing a productive option for the rural sector. With the purpose of quantifying the resource and helping regulate its use, the allometric relationships of individuals of oregano collected in 20 natural populations distributed in the municipalities of General Cepeda, Parras de la Fuente and Ramos Arizpe, Coahuila were determined, so as to select a model that estimates the dry leaf biomass (DLF) of the plant. Based on a destructive sampling, 706 plants were analyzed; their total height (TH), the larger diameter (LD) and smaller diameter (SD) of the bush, the mean diameter (MD) of the crown and the dry leaf biomass (DLB) were calculated. The variables most related to the DLB were selected with Pearson’s correlation test and utilized to adjust 10 regression models according to the PROC MODEL procedure. The model of Schumacher-Hall DLB = 0.00599(MD)^1.935454(TH)^0.256803 was used for recording R²_adj values above (0.80), as well as the lowest value for the root mean square error (RMSE, 0.304), considering the significance of its parameters (p≤ 0.0001); based on this, a double-entry table estimating the DLB of the plants was developed.