Short term fluctuations and succession trends in tropical floodplain vegetation measured by correspondence analysis

Abstract

The aim of this work was to study the aquatic macrophytes community development to distinguish the fluctuations from succession trends at different temporal and spatial scales in the Upper Paraná River floodplain. The samples were collected quarterly from May 2000 to March 2002 in seven lakes with different degrees of connectivity from the main river channel and analyzed by between-class correspondence analysis. It was difficult to establish any pattern of community development at local scale but at a higher level of organization, disconnected lakes were characterized by fluctuation of the floristic composition. Connected lakes showed a straight trajectory, indicating that succession was occurring at these sites. Probably the income of propagules and diaspores from the river into connected lakes was the driving force of the observed change in community composition.<br>Trabalhos sobre sucessão ecológica foram realizados principalmente com ecologia vegetal de plantas terrestres, onde a maioria das teorias foram concebidas. Poucos estudos abordam a vegetação de áreas alagáveis especialmente no Brasil. Este trabalho investigou o desenvolvimento da comunidade de macrófitas aquáticas tentando distinguir flutuações populacionais de tendências sucessionais em diferentes escalas temporal e espacial na planície de inundação do Alto Rio Paraná. As amostras foram coletadas a cada três meses, de maio de 2000 a março de 2002, em 7 lagoas com diferentes graus de conectividade com a calha principal dos rios, e analisadas pela análise de correspondência (CA) entre-classes. Foi difícil estabelecer qualquer padrão de desenvolvimento da comunidade sob uma escala local, mas em uma escala mais ampla, as lagoas desconectadas foram caracterizadas pela flutuação da composição florística. As lagoas conectadas apresentaram uma trajetória retilínea no diagrama da CA, indicando que a sucessão estava ocorrendo nestes locais. Provavelmente, o aporte de propágulos e diásporos para as lagoas conectadas vindos do rio é a causa da alteração na composição da comunidade

Structure of aquatic vegetation of a large lake, western border of the Brazilian Pantanal

“…The structure of the habitat, natural dynamics of aquatic vegetation and species composition of Baía do Castelo seems to be influenced by the variation in water levels, at least during the sampling period, which promotes spatial segregation, most likely due to competition and/or habitat preference. Generally, these plants can be arranged depending on the degree of connectivity with the river, time of the year, interaction among species and depth of water bodies, as described for floodplains elsewhere (Santos and Thomaz, 2007;Thomaz et al, 2007;Boschilia et al, 2008;Pitelli et al, 2008;Mormul et al, 2010;Bornette and Puijalon, 2011;Ferreira et al, 2011). Pityrogramma calomelanos, L. nervosa, I. alba, C. podantha, P. acuminatum, R. novemnervia and Ludwigia leptocarpa had higher correlation with the floating meadows, where the plants are not submerged, just their roots are constantly in water.…”

“…Some populations of aquatic plants enhance their development in shallower environments, although the reduction in water levels limits the occurrence or increases mortality of other species adapted to higher depths (Santos and Esteves, 2004;Pitelli et al, 2008). On the other hand, macrophyte assemblages in floodplains are more heterogeneous in shallow environments (Santos and Thomaz, 2007). This occurs probably because many species are persistent in marshy environments due to their highly competitive ability and are seasonally depleted during the drought, allowing the coexistence of many species of similar habits between the wet and dry periods (Junk et al, 1989;Boschilia et al, 2008).…”

“…The duration and amplitude of water levels might determine the species composition in Baía do Castelo as described elsewhere (Santos and Thomaz, 2007;Boschilia et al, 2008), however the role of fluctuations in water levels in the composition of these aquatic macrophyte assemblages is still unclear. Although we made a single sampling expedition, data reported here are of great value for understanding the patterns of distribution and cover of aquatic macrophytes in the Pantanal.…”

“…In seasonally flooded areas, the flood pulse is especially important for these ecosystems (Junk et al, 1989(Junk et al, , 2006, because it causes changes in richness and composition of aquatic macrophytes (Maltchik et al, 2007;Santos and Thomaz, 2007;Pitelli et al, 2008;Thomaz et al, 2009;Mormul et al, 2010;Ferreira et al, 2011). The distribution and establishment of aquatic macrophytes in wetlands are mostly determined by abiotic variables such as depth, water current, velocity and its physical and chemical characteristics, solar radiation, turbidity, connectivity to other water bodies and distance from the shore (Frey, 1995;Pott and Pott, 2003;Fortney et al, 2004;Neiff et al, 2005;Santos and Thomaz, 2007;Boschilia et al, 2008;Franklin et al, 2008;Pitelli et al, 2008;Santos and Thomaz, 2008;Mormul et al, 2010;Bornette and Puijalon, 2011;Ferreira et al, 2011).…”

Dinámica estacional de la vegetación litoral en el complejo lagunar inundable Zapatosa, Colombia

“…Plant communities in tropical seasonally flooded wetlands and floodplain lakes have been thoroughly studied for Northern Australia (Casanova & Brock, 2000;Finlayson, 2005;Warfe et al, 2011), india (Unni, 1971;Middleton, 1999;van der Valk, Middleton, Williams, Mason, & Davis, 1993), and Africa (Rees, 1978;Müller & Deil, 2005). in tropical and subtropical South America studies on the different aspects of the flooding cycles and their effect on aquatic vegetation were carried out in the Orinoco floodplains of Venezuelan (Castroviejo & López, 1985;Rial, 2000;2006), the Amazon (Junk, 1970;1986;Junk & Piedade, 1993;Ferreira, Piedade, Wittmann, & Franco, 2010;Piedade et al, 2010), the Pantanal (Do Prado, Heckman, & Martins, 1994;Frey, 1995;Fortney et al, 2004;Pott & Pott, 2004;Kufner, Scremin-Dias, & GuglieriCaporal, 2011;Pott, Pott, Lima, Moreira, & Oliveira, 2011), coastal Brazil (Rolon, Lacerda, Maltchik, & Guadagnin, 2008), and particularly the Paraná due to increasing river impoundments (e.g., Franceschi, Torres, Prado, & Lewis, 2000;Murphy et al, 2003;Thomaz, Souza, & Bini, 2003;Santos & Thomaz, 2007;Sabattini & Lallana, 2008;Santos & Thomaz, 2008;Padial et al, 2009;Sousa, Thomaz, & Murphy, 2011).…”