Indicadores ecológicos da ictiofauna em lagos da Amazônia: uma revisão sistemática

Abstract

The biggest river basin in the world is the Amazon basin, which has a vast number of aquatic ecosystems and an enormous extension that allows for a rich and diverse ichthyofauna. In this context, this article analyzed the foundation of scientific knowledge that states the understanding of the ichthyofauna’s organization in Amazonian lakes based on ecological indicators (abundance, richness, diversity, evenness, and dominance). From 2004 to 2023, a systematic review of the scientific literature was carried out, encompassing publications in English, Spanish, and Portuguese that reported on ecological indicators used to examine the structure of the ichthyofauna in Amazonian lakes. In order to achieve this, dissertations and these were sought in CAPES electronic databases, along with scientific articles in major indexed electronic databases: Web of Science®, SCOPUS®, and Google Scholar®. For data analysis, descriptive statistics and the one-way ANOVA test between the ecological indicators and the hydrological period were applied, with the assistance of the PAST 4.3 program. A total of 24 publications were systematically analyzed in this study, due to their direct relation to the structure of the ichthyofauna in the Amazonian lakes: one (4.2%) was obtained from the CAPES database, another (4.2%) from Web of Science®, four (16.7%) from SCOPUS®, and eighteen (75.0%) from Google Scholar®. Within the CAPES database, approximately 95% of the previously published theses and dissertations, published prior to the Sucupira platform, were inaccessible for information retrieval. The one-way ANOVA test did not reveal any significant differences in the estimates of ecological index values across the evaluated hydrological periods in the systematic review studies. Two decades of scientific publications indicate the lack of comprehensive studies aimed at understanding the structure of ichthyofauna in lacustrine environments. There’s also a possibility that existing studies have not been published in scientific journals. The majority of these publications are concentrated in the state of Amazonas, highlighting an uneven distribution of publications within the Amazonian states. Even though the statistical analysis does not clearly indicate the influence of the hydrological cycle on changes in the structure of ichthyofauna in Amazonian lakes, it is important to highlight that the analyzed publications do suggest that ecological indices are dependent on the hydrological period. The systematization of studies on ecological indicators shows the need to foster more research projects on the structure of ichthyofauna in Amazonian lakes, enhancing the understanding of these environments' functioning, which could turn in conservation efforts and/or monitoring actions for the Amazonian lakes.