Variación de rasgos de madera en bosque seco tropical a través de un gradiente de sequía en Colombia

Abstract

The dry forest in Colombia es an ecosystem that presents extreme environmental conditions, like frequent and extreme droughts, where the woody species have developed adaptations that allow them fight with these conditions. These adaptations are associate in a big percent, to the functional strategies and the wood's anatomical traits. The wood's anatomical traits fulfill important functions inside the tree like: transversal and longitudinal transport of water and nutrients, water 's storage and investment in support tissues, affecting the growth and survival of the plant. We studied the anatomical traits and the functional strategies of the wood in dry forest species and their variations through of a drought gradient. Were described eleven (11) wood's anatomical traits in sixty (60) species present in five (5) permanent plots, the microscopic description was doing in histological mounts by means of optical microscopy, following the lineaments of IAWA Committe. The majority of the functional traits presented a correlate with the drought gradient (annual precipitation and precipitation in the most dry months), between these six (6) have a positive relation, vessels length (R2= 0,086 y R2= 0,322), rays length (R2= 0,086 y R2= 0,263), rays width (R2= 0,095, y R2= 0,074), fibers thickness (R2= 0,064 y R2= 0,143), wood density (R2= 0,131 y R2= 0,209 ) and fibers length (R2= 0,343 y R2= 0,435); and two (2) have a negative relation with the gradient, pits diameter (R2= -0,086 y R2= -0,109), and moisture content (R2= -0,013 y R2= -0,117). The tolerance and evasion functional strategies present too a correlation with the drought gradient (R2= 0,211, R2= 0,241 y R2= 0,071, R2= 0,119 respectively). The results show that the wood features play an important role as a functional strategy for evasion or tolerance of plants to drought.