VIEGAS, V. M.; http://lattes.cnpq.br/0839420675131214; VIEGAS, Victor de Medeiros.
Abstract:
Water scarcity is one, if not the greatest, of the problems faced by the human population and
also by the biodiversity of the Brazilian semiarid. Paraiba's wild is one of the many
Northeastern mesoregions that have suffered from poor rainfall distribution over the past
decade. The meiofauna study emerges as a tool to analyze the ecological impacts caused by
rainfall variations. Thus, the present research aims to understand how the drought process of
the region caused impacts on the structural composition and diversity of the meiofaunistic
community of Boqueirão do Cais, municipality of Cuité / PB. Two collections were
performed in 2019, one in the rainy season (May) and one in the dry season (October). The
sediment was obtained along the left bank of the dam at 4 different points, with 3 replicates
each, totaling 24 samples in both seasons. In the laboratory, the particle size of each collection
point was analyzed for local sediment analysis. The organisms were separated from the
sediment by the washing process following the methodology of Elmgren (1976). The results
were compared with past data before the region drought period and showed the highest
occurrence of gravel in the rainy season sediment, probably originating from the water flow of
the Jacu and Campo Comprido rivers. In the dry season, fine sand was predominant.
Regarding biotic factors, MDS showed significant differences between seasons, but
similarities between their points. We found 8 taxa in the rainy season and 9 taxa in the dry
season. Nauplios, Rotiferos and Tardigrada were exclusive to our work, the mites and
Polychaeta taxa were not registered. Nematoda was well represented in both seasons, with
higher occurrence in the rainy season. In the dry season, Turbellaria, Nematoda and
Copepoda, respectively, occurred in greater numbers. Also noteworthy is the increase in
occurrence, density and abundance of the Rotifer group also in the dry season. The Diversity
and Equity Indexes, as well as the other results, show that there was an increase in diversity
and the structural reestablishment of the meiofaunistic community after the drought process.