Are Algae Relevant to the Detritus-Based Food Web in Tank-Bromeliads?

Abstract

We assessed the occurrence of algae in five species of tank-bromeliads found in contrasting environmental sites in a Neotropical, primary rainforest around the Nouragues Research Station, French Guiana. The distributions of both algal abundance and biomass were examined based on physical parameters, the morphological characteristics of bromeliad species and with regard to the structure of other aquatic microbial communities held in the tanks. Algae were retrieved in all of the bromeliad species with mean densities ranging from ∼102 to 104 cells/mL. Their biomass was positively correlated to light exposure and bacterial biomass. Algae represented a tiny component of the detrital food web in shaded bromeliads but accounted for up to 30 percent of the living microbial carbon in the tanks of Catopsis berteroniana, located in a highly exposed area. Thus, while nutrient supplies are believed to originate from wind-borne particles and trapped insects (i.e., allochtonous organic matter), our results indicate that primary producers (i.e., autochtonous organic matter) are present in this insectivorous bromeliad. Using a 24-h incubation of size-fractionated and manipulated samples from this plant, we evaluated the impact of mosquito foraging on algae, other microorganisms and rotifers. The prey assemblages were greatly altered by the predation of mosquito larvae. Grazing losses indicated that the dominant algal taxon, Bumilleriopsis sp., like protozoa and rotifers, is a significant part of the diet of mosquito larvae. We conclude that algae are a relevant functional community of the aquatic food web in C. berteroniana and might form the basis of a complementary non-detrital food web.

Bromeliad tanks are unique habitats for microbial communities involved in methane turnover

“…Diverse communities of macro-and microorganisms inhabit these tanks and are responsible for the breakdown of tank organic matter, the release of plantavailable nutrients (Ngai and Srivastava 2006) and the emission of substantial amounts of CH 4 (Martinson et al 2010) and CO 2 (Atwood et al 2013). Tank bromeliads were used as natural model systems to study food web structures (Kitching 2001;Srivastava 2006;Srivastava et al 2008;Brouard et al 2011), animal richness (Richardson 1999), activity and distribution of (aquatic) invertebrates (Carrias et al 2001;Marino et al 2013) and microorganisms (Carmo et al 2014). Many different bacteria and archaea, which are commonly found in soils, were also detected in Ecuadorian and Costa Rican tank bromeliad slurries (Goffredi et al 2011a(Goffredi et al , 2011bMartinson et al 2010).…”

Algae in phytotelmata from Caatinga: first record of the genus Rhopalosolen Fott (Chlorophyta) for Brazil

“…Bromeliads were usually exposed to the sun, which naturally contributed for high value of that variable. Recent studies demonstrate that high sun exposure is an essential factor for the presence of algae in tank bromeliads (Brouard et al 2011, Marino et al 2011, Carrias et al 2014). ).…”

“…As an example, a few studies demonstrated that algae may be an alternative energy source for some bromeliad food webs (Brouard et al 2011, Farjalla et al 2016. Other studies have shown that different algal communities may be found in different plants that are near in the same area (Carrias et al 2014), which may be related to plant architecture (Marino et al 2011) and the exposure to sun (Sophia et al 2004, Brouard et al 2011, Carrias et al 2014, Farjalla et al 2016.…”

“…As an example, a few studies demonstrated that algae may be an alternative energy source for some bromeliad food webs (Brouard et al 2011, Farjalla et al 2016. Other studies have shown that different algal communities may be found in different plants that are near in the same area (Carrias et al 2014), which may be related to plant architecture (Marino et al 2011) and the exposure to sun (Sophia et al 2004, Brouard et al 2011, Carrias et al 2014, Farjalla et al 2016. Among the main algal groups occurring in Brazilian phytotelmata are the diatoms (Lyra 1971(Lyra , 1976, coccoid green algae (Nogueira 1991), dinoflagellates (Ramos et al 2016) and desmids (Sophia 1999, Sophia et al 2004, Ramos et al 2011.…”

Aquatic invertebrates associated with bromeliads in Atlantic Forest fragments

“…Bromeliads in neotropical forests serve as habitats for bacteria (Haubrich et al 2009), algae (Brouard et al 2011), fungi (Sophia 1999), protozoa (Foissner et al 2003), arthropods and anuran amphibians (Benzing 1990, Silva et al 2011. Some invertebrates, such as oligochaetes and ostracods, spend their entire lives inside the cisterns of bromeliads (Montero et al 2010, Pinto & Jocqué 2013, while others are only found in such habitats in immature forms, mainly beetles and flies (Mestre et al 2001).…”