Early Plant Succession after Cutting and Burning in the Upper Rio Negro Region of the Amazon Basin

Abstract

Changes in vegetation structure, species composition [Cecropia ficifolia, Vismia lauriformis, Solanum stramoniifolium, Clidemia sericea, Borreria latifolia, Eupatorium cerasifolium, Panicum laxum] and species dominance were studied over the first 22 mo. of succession after the cutting and burning of several mature tierra firme (i.e., non-flooded) forest sites in southern Venezuela in the upper Rio Negro region of the Amazon Basin. To explain the observed succession, additional field investigations were undertaken. Population densities were low during the 1st months of succession because of the low density of propagules and because the low rainfall during this time was not favorable for seedling germination or establishment. The rapid increase in plant density after about the 4th mo. occurred because the early colonizers had then begun to produce, and disperse locally, large numbers of seeds. There were 6 distinct microhabitat types present on the sites after burning. Most species tested showed distinct microhabitat preferences.