EFFECTS OF ADDING LOGS IN IMPACTED NEOTROPICAL STREAMS ON THE COMMUNITY OF AQUATIC MACROINVERTEBRATES
Conserving lotic environments is important for both biodiversity protection and the functioning of human societies. However, these environments are constantly under threat. Streams are significant lotic environments and highly dependent on riparian vegetation for their natural operation. To function properly, they require services provided by riparian forests, with the supply of logs being one such service. Logs are associated with environmental improvement in streams through interactions with water flow, sediment, and the promotion of greater environmental heterogeneity and availability of ecological niches. Stream restoration processes often focus on restoring riparian vegetation. However, since it can take decades for this vegetation to grow sufficiently to provide logs, adding logs to streams becomes an interesting tactic to meet this need. This study aims to assess whether the addition of logs to streams, a common practice abroad, enhances environmental quality. Macroinvertebrates are used as bioindicators along with abiotic data. The study involves manipulating sections of two streams in Itatinga, SP, Brazil, by adding eucalyptus logs and comparing these sections to those immediately upstream and downstream. In the manipulated section, there was observed greater diversity of channel types, increased presence of structures serving as shelter, and higher levels of dissolved oxygen. Downstream, there was observed lower electrical conductivity of the water. Although the analysis of bioindicators is not yet complete, the results obtained so far indicate environmental enrichment in the presence of logs.