Invertebrados de banhados com entornos preservados e impactados na Região de campos de barba-de-bode, Rio Grande do Sul, Brasil

Abstract

The wetlands are characterized by the presence of permanent or temporary water table without flow and abundance of organic matter, which offers an ecosystem suitable for the occurrence of a great diversity of animal and vegetal groups. However, the biodiversity of these environments is directly affected by agriculture and livestock, being commonly used as a basis for irrigation in agriculture, besides offering a rich diversity of plants for feeding in livestock. Invertebrate groups are of great importance to the food chain of these environments, and as these organisms are affected the impact extends throughout the food chain. For the present study, twenty-two plots with different degrees of impact and preservation were chosen in their surroundings, aiming to perform a survey of invertebrates that occur in plains of the bearded field region, to the northwest of the Rio Grande do Sul State, with the objective of verifying how the degradation of the environmental matrices of these areas can affect the abundance and local richness of the invertebrate community. In the data collection, 4,873 invertebrates were identified from 90 táxon, classified mostly at the family level. We used several methods of comparison between the environments and it was verified that in environments characterized as impacted, because they present a matrix of environment transformed in agriculture, the richness increases gradually according to the increase of the size of the plots.