DOI: 10.20350/digitalcsic/17705
title: Quantification of aboveground and belowground biomass and associated organic carbon in two olive cultivars (Arbosana and Picual) grown at high density
title: Cuantificación de la biomasa aérea y subterránea y del carbono orgánico asociado en dos cultivares de olivo (Arbosana y Picual) cultivados a alta densidad

description: [Description of methods used for collection/generation of data] In this study, two methodologies (destructive and non-destructive) were developed and tested to quantify aboveground and belowground biomass, and their carbon content, in 7.5-year-old trees of two widely cultivated olive cultivars (Arbosana and Picual), at field and under Mediterranean climate conditions.
description: [Methods for processing the data] Differences between levels of the evaluated factors for the different measured variables were assessed using the parametric ANOVA or t-student test depending on the number of levels for the three evaluated factors (two and more than two respectively), after checking that the data met the normality, homogeneity of variances, randomness and independence hypotheses. When the assumptions of normality were not met, the non-parametric Kruskal Wallis test or the Mann-Whitney U test was carried out. Once parametric or non-parametric tests were applied, the mean values of the different levels were separated using Tukey’s post-hoc multiple comparisons test with a significance level of 5%. In those cases where the hypothesis of homogeneity of variances was not met, the Games-Howell method was applied.
description: [EN] Accurate quantification of biomass production and carbon accumulation in olive orchards is crucial for optimizing their agronomic management and assessing their potential to mitigate climate change negative impacts. In this study, two methodologies (destructive and non-destructive) were developed and tested to quantify aboveground and belowground biomass, and their carbon content, in 7.5-year-old trees of two widely cultivated olive cultivars (Arbosana and Picual), at field and under Mediterranean climate conditions. Picual accumulated more biomass (36.5 kg tree⁻¹) than Arbosana (27.5 kg tree⁻¹), mainly due to a greater investment in components like trunk and non-primary branches. Conversely, Arbosana allocated more biomass to leaves. In both cultivars, around 60% of the root biomass was at the top 25 cm of soil, and over 55% was concentrated in the root ball. Weighted average carbon concentration was 47% in aboveground biomass and 42% in roots. At the orchard scale, soil was the main organic carbon pool, around 76 t C ha-1, compared to 13-16 t C ha-1 in the total olive tree biomass. Average annual carbon accumulation rate in olive biomass ranged from 1.68 t C ha-1 yr-1 (Arbosana) to 2.16 t C ha-1 yr-1 (Picual), within the range of C fixation rates in Mediterranean agroecosystems. Destructive sampling captured cultivar differences in biomass and C content more accurately, whereas non-destructive method proved more suitable and accessible for large-scale use. These results help integrate biomass and C content data into olive genotype selection and management strategies, to increase carbon sequestration and sustainability of olive grove systems.
description: [ES] La cuantificación precisa de la producción de biomasa y la acumulación de carbono en los olivares es fundamental para optimizar su manejo agronómico y evaluar su potencial para mitigar los efectos negativos del cambio climático. En este estudio se desarrollaron y evaluaron dos metodologías (destructiva y no destructiva) para cuantificar la biomasa aérea y subterránea, así como su contenido de carbono, en árboles de 7,5 años de edad de dos cultivares de olivo ampliamente cultivados (Arbosana y Picual), en condiciones de campo y bajo clima mediterráneo. Picual acumuló una mayor biomasa (36,5 kg árbol⁻¹) que Arbosana (27,5 kg árbol⁻¹), principalmente debido a una mayor inversión en componentes como el tronco y las ramas no primarias. Por el contrario, Arbosana asignó más biomasa a las hojas. En ambos cultivares, aproximadamente el 60 % de la biomasa radicular se encontró en los primeros 25 cm del suelo, y más del 55 % se concentró en el cepellón. La concentración promedio ponderada de carbono fue del 47 % en la biomasa aérea y del 42 % en las raíces. A escala de plantación, el suelo representó el principal reservorio de carbono orgánico, con alrededor de 76 t C ha⁻¹, en comparación con 13–16 t C ha⁻¹ en la biomasa total del olivo. La tasa media anual de acumulación de carbono en la biomasa del olivo varió entre 1,68 t C ha⁻¹ año⁻¹ (Arbosana) y 2,16 t C ha⁻¹ año⁻¹ (Picual), dentro del rango de tasas de fijación de carbono reportadas para los agroecosistemas mediterráneos. El muestreo destructivo permitió captar con mayor precisión las diferencias entre cultivares en biomasa y contenido de carbono, mientras que el método no destructivo resultó más adecuado y accesible para su aplicación a gran escala. Estos resultados contribuyen a integrar los datos de biomasa y contenido de carbono en la selección de genotipos de olivo y en las estrategias de manejo, con el fin de incrementar el secuestro de carbono y la sostenibilidad de los sistemas olivareros.