LEAF FALL AND LEAF LITTER DECOMPOSITION OF Juglans neotropica DIELS (1906) (JUGLANDACEAE) IN AN ANDEAN MOUNTAIN FOREST, PIJAO (QUINDÍO), COLOMBIA

Leaf fall and leaf litter decomposition of Juglans neotropica Diels (1906) were analyzed in two forests: mature intervened forest (BMI) and young successional forest (BSJ) in the natural reserve ''El Árbol de la Cheta'', Pijao (Quindío), Colombia. Litterfall was assessed in 32 permanent plots of 0.0625 m² for 12 months; leaf litter decomposition was determined through the use of buried litter bags during six months. The total litter fall in the BMI was 48.5 kg/ha¹/year¹, and 50.9 kg/ha¹/year¹ in the BSJ. Biomass in the BMI was dominated by fruits (50.3%), and by leaf fraction in the BSJ (44.5%). Finally, there was no significant difference in litterfall between sampling sites (U = 1,108 p > 0.05). In the process of decomposition, the litter lost more than 50% of its initial weight in 90 days in the BMI, while in the BSJ it lost 46.39%. Litter decomposition was fit to a linear model with average values of k (año-1) of 1.76 in the BMI, and 1.74 in the BSJ, with an adjustment of 96.34% in the BMI, and 98.33% in the BSJ. The time required to decompose 99% of the litter was 2.6 years for the two sites. Rapid weight loss is consistent with the concentration of N (5.29%) and the C/N relation (8.37%) of the litter.