Effect of landscape and stand variables on tree species diversity in the understory of Pinus taeda plantations in Misiones province

Abstract

Forest plantations are within the most important productive activities in Misiones, Argentina. Afforestations are strongly criticized under the idea that are green deserts, non suitable as habitat for native fauna. The aim of the present study was to evaluate the regeneration of native tree species in the understory of Pinus taeda plantations and the influence of stand and landscape variables in the northwest of Misiones, Argentina. Plantations presenting different ages, previous land uses and landscape contexts were sampled. A total of 91 native tree species were found in the forest understory, and the most abundant were animal-dispersed tree species. The native tree composition of plantations understory was different from that of native forest. The similarity analysis revealed that old plantations were more similar to native forest than to young plantations. The canonical correspondence analysis (CCA) showed that previous land use was the variable with more influence on the understory composition, followed by the basal area and the distance to the native forest at the time of planting. Wind-dispersed and pioneer species were more associated with short distances to the native forest and lower basal area; whereas animal-dispersed and shade tolerant species were related to high basal area and previous land use. Results support the idea that forest plantations may represent a suitable environment for the development of native plants.