A First Quantitative Census of Vascular Epiphytes in Rain forests of Colombian Amazonia

Abstract

Epiphytism in Colombian Amazonia was described by counting vascular epiphytes in thirty 0.025-ha (5 · 50 m) plots, well-distributed over the main landscape units in the middle Caqueta´area of Colombian Amazonia. Each plot was directly adjacent to a 0.1-ha plot at which the species composition of trees and lianas (diameter at breast height (DBH) ‡ 2.5 cm) had been recorded 3 years earlier. The purpose of the study was to explore abundance, diversity, and distribution of epiphytes between the principal landscape units. A total of 6129 individual vascular epiphytes were recorded belonging to 27 families, 73 genera, and 213 species (which included 59 morpho-species). Araceae, Orchidaceae, and Bromeliaceae were the most speciose and abundant families. A total of 2763 phorophytes were registered, 1701 (62%) of which with DBH ‡ 2.5 cm. About 40-60% of the woody plants with DBH ‡ 2.5 cm carried epiphytes, which points at low phorophyte limitation throughout all landscapes. Epiphytism was concentrated on stem bases. Just as trees, epiphyte species assemblages were well associated with the main landscapes. Contrary to trees, however, epiphyte abundance and diversity (species richness, Fisher's alpha index) hardly differed between the landscapes. This calls for caution when explanations for distribution and dynamics of tree species are extrapolated to growth forms with a totally different ecology.

Floristic composition and community structure of epiphytic angiosperms in a terra firme forest in central Amazonia

“…The relevance of Araceae to the epiphytic community recorded in the present study confirms the results obtained by other authors in different regions of the extra-Brazilian Amazon, where this family contributed the greatest diversity of species (Balslev et al 1998;Rudas & Pietro 1998;Vasco 2002;Arévalo & Betancur 2004;Benavides et al 2005;, as well as a study in the Brazilian Amazon (Pos & Sleegers 2010). The high abundance of Araceae recorded in the present survey is also similar to results found in studies in the Venezuelan Amazon, where this family contributed 47% of specimens sampled (Nieder et al 2000), which represented 43.3% of total abundance and in the Colombian Amazon, where Araceae contributed 58.8% of specimens and 76% of the epiphytic biomass of the sampled site (Benavides et al 2006).…”

“…Philodendron had the highest generic diversity and abundance in the present study, a result that is consistent with those obtained by Nieder et al (2000) and Benavides et al (2005;. The representativeness of Philodendron is also cited in other Brazilian forest formations.…”

“…Furthermore, in many regions, it is uncommon for members of this family to present epiphytism. Nonetheless, the diversity of the family recorded in the present study is similar to results found by Benavides et al (2005) in the Colombian Amazon, where the authors recorded 16 species and 418 individuals, classifying them as holoepiphytes or hemiepiphytes. However, in the present study specimens from Melastomataceae were classified as accidental or facultative epiphytes, as these occurrences can be dispersive accidents with successful germination, and thus, merely examples of colonization of a epiphytic habitat, as these plants are usually terrestrial (trees, shrubs and lianas).…”

“…The number of epiphytic species recorded exceeds those cited in some studies in locations such as the Venezuelan Amazon Nieder et al 2000;Schmit-Neuerburg 2002) and the Colombian Amazon (Vasco 2002;Benavides et al 2006;. However, the epiphytic richness of the Urucu area was lower than that recorded in other forests in the extra-Brazilian Amazon (Baslev et al 1998;Arévalo & Betáncur 2004;Kreft et al 2004;Benavides et al 2005), as well as studies in the Brazilian Amazon (Ribeiro et al 1999). The different methods used to quantify epiphytic flora, such as the size variation in the sample areas, the inclusion or exclusion of some epiphytic taxa, or differences in the criteria used to define AD -absolute density; Npi -Number of phorophytic individuals occupied by epiphytic species i; Spi -number of phorophytic species occupied by epiphytic species i; RFi -relative frequency on phorophytic individuals; RFj -relative frequency of specific phorophytes; IVe -epiphytic importance value.…”

“…In the Amazon biome lack of information is even greater, although in the extra-Brazilian Amazon stand out studies by Baslev et al (1998), , Nieder et al (2000), Nieder et al (2000), SchmitNeuerburg (2002), Vasco (2002), Arévalo & Betáncur (2004), Kreft et al (2004) and Benavides et al (2005;. In the Brazilian Amazon we can cite studies by Silva et al (1995), Ribeiro et al (1999), Sousa & Wanderley (2007), Pos & Sleegers (2010), Medeiros & Jardim (2011) and Quaresma & Jardim (2012).…”