Feeding diversity in macroinvertebrate communities: A contribution to estimate the ecological status in shallow waters

Abstract

The feeding diversity of subtidal samples of macroinvertebrates from Ria Formosa was estimated with Shannon Wiener information index and complementary evenness. The results were compared with other commonly used methodologies under the European water framework directive, such as diversity indices, AMBI and ITI.Assuming that in a healthy environment all feeding groups are present, and that no group clearly dominates, the feeding diversity is expected to be maximal and the evenness feeding diversity will be close to 1. In degraded environments some feeding groups might be absent or having low relative abundance, and generally with one or two groups dominating the community. In this way the evenness feeding diversity index would measure deviations from expected values due to a degradation of the environment. Although confirmation of this approach needs to be tested in other shallow waters, the results obtained show interesting features.To each of the 297 species belonging to the Ria Formosa data matrix a feeding group was assigned, among six groups: surface deposit feeders, sub surface deposit feeders, herbivores, suspension feeders and suspension/deposit feeders (species which have the two feeding modes depending on food availability). The carnivorous, parasites, omnivorous and scavengers were all grouped together, forming the sixth group. Most of the stations of Ria Formosa showed high feeding diversity, which could correspond to a good or high ecological status (ES) except at one location, that occasionally showed low feeding diversity. This poor condition was essentially due to low water renewal and extreme environmental variation of some parameters, such as salinity. At some locations an intermediate feeding diversity was observed mainly due to natural accumulation of organic matter. Other commonly used indices also point out to the same tendencies. 2We propose the evenness feeding diversity estimate approach as a practical and apparently robust method to estimate the ES of shallow waters, which can be used together with other common indicators.This approach has also the advantage of showing low sensibility to small samples and to low taxonomic identification effort.

Relationship between space distribution of the benthic macroinvertebrates community and trophic state in a Neotropical reservoir (Itupararanga, Brazil)

“…Many works demonstrate that benthic macroinvertebrates community can also be altered in response to anthropogenic environmental changes, as land uses (Miserendino et al 2011), riparian forest impacts and effluents loading (Baptista et al 2007, Couceiro et al 2007, Gamito & Furtado 2009, Sharma & Rawat 2009 and also by pollution by industrial effluents (Moreno & Callisto 2006). Several taxa from benthic macroinvertebrates community and a wide range of biological indexes and metrics have been widely employed as environmental indicators (Bode et al 2002, Mandaville 2002, Fusari & Fonseca-Gessner 2006, Baptista et al 2007, Baptista 2008, Angradi et al 2009).…”

The importance of habitat-type for defining the reference conditions and the ecological quality status based on benthic invertebrates: The Ria Formosa coastal lagoon (Southern Portugal) case study

“…In sandy bare bottoms, the opposite occurs; there is a lower number of species but a dominance of suspension-feeders (Gamito, 2008;Gamito and Furtado, 2009). In this habitat, the diversity decreases but the AMBI values also decrease and consequently the reference values for EQS evaluation must be different.…”

“…As described in the methodological approach, for significant groups the 95 percentile values were adopted regarding Margalef and ShannonWiener indices; while the AMBI reference values were adjusted to better reflect the expected community composition at shallow coastal lagoons habitats. In general, it was observed that an important proportion of the communities across all habitats at the lagoon was constituted by tolerant species (ecological group EG III) (Figure 4), which are more adapted to the natural environmental fluctuations in the lagoon (Gamito and Furtado, 2009). At muddier sediment habitats (H2 and H4) there was no clear dominance of sensitive species (EG I and EG II) over the remaining groups, and as expected, the presence of opportunistic species (EG IV and V) was of considerable importance; even at seagrass beds (H2) were EG I and II were very well represented.…”

Biological Monitoring of Harnoi Stream Water Quality, Abbottabad, North Pakistan

“…Technol. Dev., 35 (3): 98-109, 2016 some feeding groups might be absent or having low relative abundance and, generally, with one or two groups dominating the community (Gamito and Furtado, 2009).…”