Late Quaternary vegetation, climate and fire history from the tropical mountain region of Morro de Itapeva, SE Brazil

Abstract

Late Quaternary paleoenvironments have been interpreted from a 35,000 yr B.P. pollen and charcoal record from Morro de Itapeva (22°47′S, 45°32′W, 1850 m a.s.l.) in the SE Brazilian highlands. Changes in taxa composition and elevational shifts in high elevation grassland (campos de altitude), Araucaria forest, cloud forest and Atlantic rain forest, all of which can be found in the study area today, indicate climatic changes in the past. Expanded high elevation grasslands, absence of Araucaria forest, cloud forest and Atlantic rain forest during the recorded last glacial period (ca. 35,000–17,000 yr B.P.) suggest a climate markedly cooler and drier than today. Development of a Sphagnum peat bog, rare presence of Araucaria forest taxa and existence of a narrow cloud forest and rain forest belt at lower elevations during the late glacial period (17,000-ca. 10,000 yr B.P.) indicate a change to a cool and somewhat moister climates. During the early Holocene cloud forest developed close to the study site, reflecting a warm and moist climate on the east facing slopes, but a drier climate on the highland plateau, evidenced by the rare presence of Araucaria and Podocarpus. Only during the late Holocene moisture increases in the highlands, suggested by the higher frequency of Araucaria and Podocarpus. Fires were more frequent during the last glacial than during the Holocene.