Post-cultivation Secondary Succession in a Venezuelan Lower Montane Rain Forest

Since tropical rain forests are widely threatened by conversion to agriculture, even within protected areas, an understanding of recovery processes is important for restoration of forest ecosystems and thus conservation of their biodiversity. Secondary succession following land clearance and crop cultivation was studied in a lower montane rain forest in a protected area of the Venezuelan Cordillera de la Costa Central. Forest recovery was studied using a chronosequence of eight 20 × 20 m plots which represented four forest types ca.10 year-old Secondary Forest, ca. 20 year-old Secondary Forest, ca. 35 year-old (uncultivated) secondary forest and mature forest. Species richness and structural complexity increased during succession, with the oldest secondary forest having a physiognomy comparable to the mature forest. Species diversity was lower in the secondary forests than the mature forest, and their floristic composition was distinct. Four phases are hypothesized to occur in the succession process, each with a distinctive species assemblage: initial colonisation by non-woody vegetation; establishment and canopy closure by short-lived small-seeded woody pioneer species; replacement by longer-lived secondary species; and gradual replacement by mature forest large-seeded climax species. Full recovery of the forests in the protected area is likely to take many years, although it may be assisted through conservation management measures.