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

Author(s)

de Souza Beghelli, Frederico Guilherme ^[1] ; Alves dos Santos, Andre Cordeiro ^[1] ; Urso-Guimaraes, Maria Virginia ^[1] ; Calijuri, Maria do Carmo ^[2]

Affiliation

^[1] Univ Fed Sao Carlos UFSCar, Dept Biol, Sorocaba, SP - Brazil

^[2] Univ Sao Paulo, Dept Hidraul & Saneamento, Escola Engn Sao Carlos, Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Biota Neotropica; v. 12, n. 4, p. 114-124, OCT-DEC 2012.
• Web of Science Citations: 7

Abstract

The purpose of this work was to verify the benthic macroinvertebrates community responses through environmental factors along a headwater tropical reservoir. Samplings were taken with a Van-Veen grab along the reservoir in littoral and profundal regions and in the headwater, next to the dam and the middle of the reservoir. Samples were taken during both wet and dry seasons. Dissolved oxygen concentrations, electric conductivity, temperature and pH near the sediment have been performed in situ, at every sampling station by using a multiprobe and Secchi disc. Total water phosphorus and chlorophyll a concentrations were analyzed to determine the trophic state index. Sediment's organic matter, total phosphorus, nitrogen concentrations and granulometric composition were measured. In order to verify which environmental variables would have more influence over the benthic macroinvertebrates community, a canonical correspondence analysis (CCA) was performed. The total number of recorded taxa was 28. Among them, the family Chironomidae (Diptera) was the richest group (19 taxa). It can be proposed that the benthic macroinvertebrates community may be influenced by environmental conditions such as nutrient and organic matter availability, as well as dissolved oxygen concentration. Macroinvertebrates are adequate bioindicators of water quality due to their sensibility to environmental changes mentioned before. Chironomus sp, Limnodrilus hoffmeisteri and Branchiura sowerbyi comprises a group that can be considered bio-indicators of eutrophic conditions. A second group can be considered as indicator of mesotrophic conditions. The presence of two or more members from that group which comprises Tanytarsini spp, Fissimentum sp, Pelomus sp and Goeldichironomus sp, like predominant taxa, may indicates mesotrophic conditions. (AU)

• FAPESP's process: 08/55636-9 - Contribution to carbon cycle in Itupararanga reservoir as subsidy for sustainability in Sorocaba watershed, São Paulo, Brazil
• Grantee: Maria do Carmo Calijuri
• Support Opportunities: Research Projects - Thematic Grants