Longitudinal dynamic of Pitangueiras stream, Barretos/SP and effects of human activities on spatial and temporal distribution of aquatic macrophytes community

Abstract

The spatial and temporal dynamic of rivers depend on their interaction with watershed and regional hydrology flutuantion. This dynamic may be interrupted due to human activities, that changes the compartments and communities along the longitudinal gradient of river. Several characteristics of aquatic environment are related to occurrence and distribution of macrophytes. The water bodies pollution may cause a "Descontinuum" of the spatial and temporal distribution of macrophytes community. In lotic environment to understand the influence of the human activity, abiotic and biotic factors on the distribution of macrophytes is necessary approach the environment characteristics under different special scales. The Pitangueiras stream (Barretos, São Paulo State) receives domestic, industrial and livestock effluent. Therefore, the aim of this work will be to known the compartments and understanding the dynamic of connected process from source to mouth of Pitangueiras stream and evaluate the effects of human activities on the structure and distribution of aquatic macrophytes, considering a multispatial approach (in regional, site and spot scale). Three samples units (UA´s) with 200 m each will be determined: one UA near of Pitangueiras stream source, one at intermediate part of stream (about 20 km downstream from the source) and one UA near of Pardo river. In the UA´s will be determined the macrophytes presence or absence, margin slope measures, incident radiation and depth measurements, canopy opening in the stream, light attenuation coefficient and limnological variables. It is hoped that the results of this work to understand the longitudinal dynamic of Pitangueiras stream and the effects of inlet of fertilizer and wastewater on the structure and spatial and temporal distribution of aquatic macrophytes. (AU)