Oligochaeta (Annelida: Clitellata) em córregos de baixa ordem do Parque Estadual de Campos do Jordão (São Paulo, Brasil)

Abstract

This study aims to survey species and to better understand the spatial distribution of the Class Oligochaeta in low order streams at Campos do Jordão State Park (PECJ) in the state of São Paulo, Brazil. For this purpose, three aspects were examined and presented as chapters in this dissertation: 1) a survey of the variety of Oligochaeta; 2) spatial and temporal distribution of Oligochaeta species; 3) mesoscale distribution (mesohabitats) of Oligochaeta species. Samples of the fauna were collected between May 2005 and May 2006 in stretches of Galharada, Campo do Meio and Serrote streams using a Surber sampler. In general, our results indicate that: 1) despite the peculiar characteristics of PECJ’s low order streams, the Oligochaeta fauna was considered quite rich; 2) the use of fine techniques in sample processing resulted in satisfactory sample coverage, making this use necessary for surveys of Oligochaeta species in environmental conservation areas; 3) apparently, the main factors influencing the Oligochaeta community composition are hydrological processes in the streams and food intake; 4) Tubificidae species showed greater affinity for non-flowing habitats with organic debris, while Naididae species showed greater affinity for flowing habitats where vegetable debris are retained. Our findings point to the importance of maintaining preserved areas for the conservation of biodiversity, as any alteration to these environments may cause drastic losses in the communities’ composition.