Aquatic macroinvertebrates associated with Eichhornia azurea (Swartz) Kunth and relationships with abiotic factors in marginal lentic ecosystems (São Paulo, Brazil)

Abstract

Marginal lakes are characterised by their having high biological diversity due to the presence of aquatic macrophytes in their coastal zones, providing habitats for refuge and food for animal community members. Among the fauna components associated with macrophytes, aquatic macroinvertebrates are important because they are an energy source for predators and fish. In six lakes and two different seasons (March and August 2009), the ecological attributes of aquatic macroinvertebrate community associated with Eichhornia azurea were compared and the controlling environmental factors were identified. Since the attributes of macroinvertebrate community are strictly associated with abiotic variables of each distinct habitat, our hypothesis was that each site associated with the same floating aquatic macrophyte (E. azurea) should have a typical composition and density of organisms. We identified 50 taxa of macroinvertebrates, with greater taxa richness for aquatic insects (37 taxa) divided into eight orders; the order Diptera being the most abundant in the two study periods. On the other hand, higher values of total taxa richness were recorded in August. Dissolved oxygen and pH presented the greatest number of significant positive correlations with the different taxa. The animals most frequently collected in the six lakes in March and August 2009 were Hirudinea, Oligochaeta, Hydrachnidae, Conchostraca, Ostracoda, Noteridae, Ceratopogonidae, Chironomidae, Culicidae, Caenidae, Pleidae, Aeshnidae, Libellulidae, Coenagrionidae and Nematoda. Only densities of Trichoptera, Ostracoda and Conchostraca presented the highest significant differences between lakes in both study periods and considering the composition of macroinvertebrates no significant differences were registered for macroinvertebrate composition.Keywords: phytofauna, aquatic macrophyte, marginal lakes. Macroinvertebrados aquáticos associados à Eichhornia azurea (Swartz) Kunth e suas relações com as variáveis abióticas em ecossistemas lênticos marginais (São Paulo, Brasil) ResumoLagoas marginais são caracterizadas por apresentar elevada diversidade biológica, devido à presença de macrófitas aquáticas nas suas zonas litorâneas, constituindo habitats de refúgio e alimento para comunidades associadas. Entre os seus integrantes, destacam-se os macroinvertebrados aquáticos, fonte de energia para predadores e ictiofauna. Em seis lagoas e em duas épocas distintas (março e agosto de 2009), os atributos ecológicos da comunidade de macroinvertebrados aquáticos associados à Eichhornia azurea foram comparados, identificando-se os fatores ambientais controladores. Uma vez que os atributos da comunidade de macroinvertebrados estão estritamente associados às variáveis abióticas de cada habitat distinto, nossa hipótese era de que cada local com a presença da mesma macrófita aquática flutuante (E. azurea) deveria ter uma típica composição e densidade de organismos. Foram identificados 50 taxa de macroinvertebrados, com maior riqueza registrada para os insetos aquáticos (37 ...

Benthic macrofauna and the limnological parameters of a first-order stream in Atlantic Forest of Brazilian Northeast

“…The dominance pattern of macroinvertebrates found in this study is commonly observed in others studies, which the class Insecta has a higher frequency and the family Chironomidae with greater abundance (Giuliatti and Carvalho, 2009;Silva and Henry, 2013).…”

“…Their use in aquatic environmental impact assessments becomes frequent due to the great potential bioindicator and can be classified in three main groups (sensitive, tolerant or resistant) related to tolerance of adverse conditions (Goulart and Callisto, 2003;Holt and Miller, 2010). Therefore, they are considered important for the structure and functioning of aquatic ecosystems and their composition may be related to abiotic conditions influencing the structuring and distribution of individuals (Ribeiro and Uieda, 2005;Silva and Henry, 2013).…”

Coleoptera associated with macrophytes of the genus Salvinia in four oxbow lakes in two river basins in southeast Brazil

“…This is in contradiction with a report by Silva and Henry (2013) that the richness and abundance of macroinvertebrates associated with Eichhornia azurea were greater in the period when the river-lake connectivity was higher; they explained this in terms of the probable influence of the flood pulse, which would favor greater heterogeneity of habitats for the community. Fulan et al (2011) recorded that Lake Cavalos, despite being small and isolated, has a considerable density of fish, which can prey on Odonata larvae.…”

“…Boneto et al (2011) observed that the greatest number of hydrophilids was found in stands of Eichhornia azurea (blue water hyacinth) in Lake Cascalho in the Upper Paraná River basin (MS, Brazil), while Moretti et al (2003) recorded the largest number of dytiscids on Pontederia lanceolata in Coqueiro Bay, Poconé Swamp (MT, Brazil). Silva and Henry (2013), in a comparative study of the macroinvertebrate phytofauna associated with Eichhornia azurea in 6 oxbow lakes on the Parapanema River, identified Dytiscidae, Noteridae and Hydrophilidae, at both the larval and adult stage, noterid larvae being the most abundant. Many species in the families Dytiscidae and Noteridae are known to associate with aquatic plants possessing aerenchyma, using them for oviposition and pupation, while those in other families, such as Hydrophilidae and Scirtidae, use aquatic macrophytes possibly as a source of food, given that most of these species are herbivorous (Benetti and Cueto, 2004).…”

Macroinvertebrados aquáticos associados às raízes de Eichhornia azuera (Swarts) Kunth (Pontederiaceae) em uma lagoa marginal no Pantanal, MS

“…Macró tas nas regiões litorâneas desempenham importante papel ecológico na estruturação da comunidade de macroinvertebrados associados (WALKER et al, 2013), proporcionando, além de local para deposição de ovos e refúgio contra predadores, fonte indireta de alimento para raspadores, que utilizam o biofilme que se adere às paredes do vegetal, e direta para as espécies minadoras e fragmentadoras (VILLANUEVA; TROCHINE, 2005), que utilizam o tecido vegetal como fonte de alimento (NEWMAN, 1991). A complexidade da estrutura morfológica e alta produção de biomassa desses vegetais são fatores que in uenciam na estruturação da comunidade de macroinvertebrados aquáticos, alterando a abundância e a riqueza faunística através de maior ou menor disponibilidade de habitats (DIBBLE; THOMAZ, 2006) e também pela alteração das características abióticas da água, como por exemplo, pH e oxigênio (SILVA;HENRY, 2013). Eichhornia azurea é uma macró ta aquática enraizada com folhas utuantes, que apresenta ampla distribuição nos ecossistemas de água doce das Américas e é popularmente conhecida como aguapé ou camalote (POTT; POTT, 2000).…”