Introduction of native tree species into degraded Cerrado vegetation

Abstract

Experimental restoration using tree seedlings is a common strategy for accelerating succession on degraded post-agricultural land formerly occupied by Cerrado vegetation. Seedling growth in degraded tropical lands is constrained by various factors. The goal of this study was to evaluate the seedling growth and survival of seven native tree species used to accelerate forest recovery in a gully area with stressful environmental conditions. The experimental design involved fenced and unfenced blocks, presence and absence of fertilization and use of an adhesive to prevent ant herbivory (four treatments with four replicates). Seedlings were planted in December 2006 and collection of data on seedling basal diameter, height, mortality and herbivory started on January 24th 2007 and continued every three months, until final data collection on January 31st 2009 (9 measurement dates). Overall seedling survival was 38 % and protecting seedlings did not influence growth, but seedlings grew faster in response to the addition of fertilizer containing N, P and K. The use of the adhesive Tanglefoot to exclude leaf cutter ants had no influence on growth. Fencing reduced seedling mortality, but combining fencing with Tanglefoot did not. Nutrient availability limits seedling growth and survival in the gully. Direct planting of seedlings of native trees may accelerate succession in degraded Cerrado lands subject to interventions that overcome constraints on seedling growth and survival.