Grupos funcionales alimentarios de macroinvertebrados acuáticos en el río Gaira, Colombia

Abstract

Functional feeding groups of macroinvertebrates in Gaira river, Colombia. Tropical rivers are frequently described on their biodiversity but few studies have considered the ecological value of this richness in their food webs. We determined the trophic structure of aquatic macroinvertebrate communities (expressed in the richness and abundance of taxa and biomass proportions of different functional feeding groups) at the level of the river, stretch and microhabitats (functional units-UFs). We evaluated the spatial and temporal variation of these descriptors during wet and dry events, and selected three sites associated with different altitudinal belts. We reported 109 taxa, with 11 167 individuals who contributed 107.11g of biomass. Density of macroinvertebrates was favored with increasing height, and biomass showed the opposite pattern (K-W=10.1, d.f.=1, p<0.05), due to the addition of large crustaceans (Macrobrachium), and the taxa diversity was higher in the middle stretch of the river (H'=3.16). The Gaira stream runs through a mid-sized river basin, for this reason we found mainly bedrock (epilithon=50.5%), gravel and sand (43.7%). The functional unit with more habitat and food resources that contains a higher abundance of leaf litter macroinvertebrates was foliage followed by epilithon, fine sediment and gravel-sand (K-W=25.3, d.f.=3, p<0.05). The biomass values of these organisms were higher in leaves followed by gravel-sands, epilithon and sediment (K-W=15.3, d.f.=3, p<0.05). Autochthonous biomass input by different functional feeding groups can be considered very low, but they define the functionality of the stream, being represented almost exclusively by shredders (Macrobrachium, 73%), present only in the lower reaches, followed by shredder Leptonema with 15%, located mostly in the upper reaches and predatory stoneflies of the genus Anacroneuria to 6.56%, which dominated in the middle stretch of stream. Excluding Macrobrachium from the analysis, there was dominance of Anacroneuria in the lower reaches. Between rainfall and drought events, biomass of functional feeding groups was higher in rain (W=10.1, d.f.=1, p<0.05), favoring the growth of decapods, but the abundance was much higher during drought events.

The role of the hydrological cycle on the temporal patterns of macroinvertebrate assemblages in an Andean foothill stream in Colombia

“…The identification of organisms was performed to the lowest taxonomic level possible using the keys of Edmonson (1959), Hungerford and Matsuda (1960), Edmunds (1976), Wiggins (1977), Correa (used 1980), McCafferty (1981, Álvarez (1982), Arango (1983), Bedoya (1984), Machado (1989), Domínguez and Peters (1992), Spangler and Santiago (1992), Domínguez et al (1994), Merritt and Cummins (1996), Aristizábal (2002), Posada and Roldán (2003) and Manzo (2005). The assignment of functional groups for most taxa was based on Merritt and Cummins (1996), Tomanova et al (2006), Mathuriau et al (2008), Chará et al (2010), Rodríguez-Barrios et al (2011) and Ramírez and Gutiérrez-Fonseca (2014). Studies on Neotropical rivers were preferred because the life histories of many taxa differ from their counterparts in temperate regions.…”

“…In Colombia, studies on macroinvertebrate assemblages focus on issues such as the taxonomic diversity and/or their role as indicators of water quality (Roldan, 1988;Álvarez, 2005;Álvarez et al, 2006). Additional important contributions have focused on the trophic structure (Gutiérrez, 2006;Chará et al, 2010;Rodríguez-Barrios et al, 2011;Ramírez and Gutierrez-Fonseca, 2014) or drift phenomena (Rodríguez-Barrios et al, 2007;Aguirre-Pabón et al, 2012). The studies of Blanco (2003) and Longo et al (2010) were among the few whose goal was to understand the dynamics of macroinvertebrate communities in the Colombian Andes and its relationship with the hydrological cycle.…”

Estructura trófica de los invertebrados acuáticos asociados a Egeria densa (Planch. 1849) en el lago de Tota (Boyacá-Colombia)

“…Los cálculos muestran una conectancia dirigida de 0,13 y una densidad de conexiones de 2,95. aquellos que se alimentan de más de un nivel trófico. Según Sánchez-Carmona et al (2012), constituyen un factor fuertemente estabilizador en las redes alimentarias, en este caso, el hemíptero: Corixidae, puede consumir diferentes recursos que incluyen detritus, perifiton y pequeños insectos de cuerpo blando (Martin, 1969;Tomanova y Usseglio-Polatera, 2007), y el quironómido Ablabesyia sp., en algunos estudios considerado como depredador (Blanco-Belmonte, 1990;Rodríguez-Barrios et al, 2011;Rivera et al, 2013) y en otros como colector-recolector (Chará-Serna et al, 2010). Este tipo de consideraciones muestra la alta plasticidad que exhiben algunos taxones neotropicales en sus hábitos alimenticios, que muestran tendencias a la omnivoría, característica que les facilita adaptarse a las condiciones fluctuantes del trópico (Tomanova et al, 2006;Chará-Serna et al, 2010;Guzmán-Soto y Tamaris-Turizo, 2014).…”

Assigning functional feeding groups to aquatic arthropods in a Neotropical mountain river

“…In the rivers of the Sierra Nevada de Santa Marta, Trichoptera are represented by one Sh-Dt genus (Phylloicus), 2 genera cataloged as Ft (Leptonema and Smicridea) and a Pr (Atopsyche). The orders Plecoptera and Megaloptera are each represented by just one genus of Pr (Tamaris-Turizo et al 2007, Rodríguez-Barrios et al 2011, Guzmán-Soto & Tamaris-Turizo 2014, Granados-Martínez et al 2016. Additionally, some groups (e.g.…”