Abstract

LOZANO-BOTACHE, Luis Alfredo; MELO-CRUZ, Omar Aubrelio  and  LOZANO-CASTELLANOS, Luisa Fernanda. The diametric growth of Anacardium excelsum is affected by local climatic variation in Tolima, Colombia. Bol. Cient. Mus. Hist. Nat. Univ. Caldas [online]. 2025, vol.29, n.2, pp.13-32.  Epub Apr 14, 2026. ISSN 0123-3068.  https://doi.org/10.17151/bccm.2025.29.2.1.

Anacardium excelsum is a commercially valuable species found in Colombia's tropical dry forests (bs-T), which are highly vulnerable to climate variability and further impacted by deforestation, habitat fragmentation and overexploitation of timber resources. Assessing its diameter growth provides insight into how it responds to such fluctuations. This study analysed the annual current increment (ACI) in the diameter of 23 individuals over 11 years in two permanent plots measuring 40 x 50 m. These plots were located in minimally disturbed bs-T remnants in the northern department of Tolima, in the municipalities of Alvarado and Venadillo. A Climate Anomaly Index (CAI) was developed based on a mathematical model grounded in IDEAM methodologies, integrating temperature and precipitation anomalies. Data were obtained from the SISDHIM (IDEAM), hydrological models (CHAC and HEC-HMS) and the NASA POWER viewer. The ACI was calculated from annual diameters and its relationship with the CAI was assessed using the unweighted pair group method with arithmetic mean (UPGMA) to identify patterns of interannual similarity and clusters of periods with comparable responses. Initial diameters ranged from 11.33 to 112.3 cm, and the species exhibited an average growth rate of 0.84 cm per year, with greater increments observed in the medium and large diameter ranges. The CAI exhibited a significant ENSO influence, with precipitation anomalies reaching +20% during La Niña and −30% during El Niño, while temperature anomalies were more moderate at −1 to +0.5 °C. The CAI responded proportionally to these anomalies, showing greater growth in wet years and reductions in dry periods with no evidence of zero diameter growth. UPGMA analysis revealed recurrent response patterns to the climatic regime, confirming that A. excelsum diameter growth is primarily conditioned by fluctuations in water availability. This methodology effectively characterised this relationship, providing key information for management and conservation strategies in the context of climate change.

Keywords : arboreal growth; climatic anomaly; climate variability; El Niño-Southern Oscillation (ENSO); tropical dry forest.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )