Estructura y composición de la vegetación ribereña de la barranca del río Tembembe, Morelos, México

Abstract

Structure and composition of the riparian vegetation of the middle-upper basin of the Tembembe river, in the state of Morelos, was analyzed. Height, diameter at breast height, crown area and taxonomic identity of each individual having a DBH 1 cm were recorded in 23 quadrats of 100 m2 each. A total of 74 species and 516 individuals were found. Mean density was 2,148 ind. ha-1, mean basal area was 88.39 m2 ha-1, and mean height (of individuals with DBH 20 cm) w as 10.5 m. Classification analysis allowed the discrimination of three communities whose distribution was associated to the altitudinal gradient: the first (G1) in the upper part (1,700 - 1,650 m a.s.l.) was dominated by species (like Alnus acuminata) having a holartic affinity; the second (G2) at an  intermediate altitude (1,640 - 1,340 m a.s.l.) was dominated by Trema micrantha; and the third (G3) in the lower portion (1,210 - 1,110 m a.s.l.) dominated by species (like Daphnopsis salicifolia) having a tropical affinity. Diversity, density and crown cover did not differ among them, but mean basal area was largest in the highest and lowest communities than in the intermediate one. Mean height of the tree layer decreased with altitude. This study contributes to the knowledge of the riparian vegetation in Morelos state and provides basic ecological information for future restoration programs of the riparian vegetation of the Tembembe river