Plant succession in a forest on the Lower Northeast Slope of Serra Geral, Rio Grande do Sul, and Holocene palaeoenvironments, Southern Brazil

Abstract

The study of plant succession provides information on vegetation dynamics of a region and, therefore, improves our understanding of the natural trends of present ecosystems. With this objective, plant succession based on palynology of a sediment profile in a swamp forest was studied on the Lower Northeast Slope of Serra Geral, Rio Grande do Sul. Samples were treated with HCl, HF, KOH and acetolysis; slides were mounted in glycerol-jelly. For each sample a minimum of 500 grains of pollen + pteridophyte and bryophyte spores was counted and other palynomorphs were counted in parallel. Tilia and Tilia Graph software were used to construct percentage and concentration diagrams, with three 14C datings. The results show a local water reservoir in the beginning of the Holocene (± 9800 yrs. BP), creating a herbaceous plant marsh by hydrosere. The initial colonization of the marsh by trees occurred about 8800 yrs. BP, with tropical species from the Coastal Plain migrating in an east-west direction. Afterwards, there was a dry phase between 7000-5000 yrs. BP. The second appearance of regional tree species began at about 5000 yrs. BP, resulting in the present forest and in the west-east migration of tropical species from interior lowlands, like this one, to re-colonize the coast after the last marine regression.

New insights into vegetation, climate and fire history of southern Brazil revealed by a 40,000 year environmental record from the State Park Serra do Tabuleiro

“…A pollen profile from São Francisco de Paula, on the eastern plateau of southernmost Brazil (Serra Geral), indicates that temperature and moisture increased at the beginning of the Holocene (Leonhardt and Lorscheitter 2010). The pollen record from Serra Velha on the lower slope of the Serra Geral about 330 km south of the Ciama 2 site shows the occurrence of Atlantic rainforest taxa at about 8800 and 5000 B.P., indicating the migration of tropical species from east to west since the early Holocene (Leal and Lorscheitter 2007). However, Behling (1995) demonstrated for the highlands of Santa Catarina state that Campos vegetation continued to prevail until ca.…”

“…along the coastal plain and valleys of Rio Grande do Sul. More recently, Leal and Lorscheitter (2007) propose the occurrence of some Atlantic rainforest species in Serra Velha on the lower slopes of the Serra Geral, Rio Grande do Sul since 8800 B.P. However, with the exception of Behling et al (2004), who reported environmental changes over a time frame of 42840 B.P.…”

Fungos, criptógamas e outros palinomorfos holocênicos (7908±30 anos AP-atual) da Planície Costeira sul-catarinense, Brasil

“…Para o sul do Brasil, nas últimas décadas, estes regimes climáticos têm sido discutidos em diversos trabalhos de palinologia do Quaternário, tais como: Behling (1993Behling ( , 1995Behling ( , 1998Behling ( , 2002; Neves (1991Neves ( , 1998; Neves & Lorscheitter (1992, 1995a, 1995b; Behling et al ( , 2004Behling et al ( , 2007; De Oliveira et al (2005); Leal & Lorscheitter (2007) e Macedo et al (2010), dentre outros.…”

Grãos de pólen de angiospermas do Holoceno (7908±30 anos AP-atual) da Planície Costeira sul-catarinense, Brasil

“…Para o sul do Brasil, os regimes climáticos do Quaterná-rio têm sido discutidos em diversos trabalhos de palinologia: Behling (1993Behling ( , 1995Behling ( , 1998Behling ( , 2002; Neves (1991Neves ( , 1998; Neves & Lorscheitter (1992, 1995a, 1995b, 1996; Behling et al ( , 2004Behling et al ( , 2007; De Oliveira et al (2005); Leal & Lorscheitter (2007) e Macedo et al (2010).…”