ROLE OF VEGETATION INDUCING SEDIMENTATION IN AN ARTIFICIAL EARTH CHANNEL

Abstract

The biogeomorphic role of vegetation has been explored in different contexts with advances in the understanding of sedimentation and hydrodynamic changes in channels and riparian zones. However, it is yet to be better established regarding their role in small earth-derived canals water gullies, the development of these issues, and canal users. These cases present some ambiguity based on the presence of vegetation with both a positive filtering role and a negative role due to competition for water resources. This study verified whether vegetation development has more prominent role as reducer of the transport of suspended sediments along the artificial channel than the natural river system, focusing on the role of vegetation as a filter of the sedimentary load. We monitored the scenario in terms of vegetation growth by gathering statistically related data on discharge, flow velocity, and turbidity. Our results indicate the main influence of the natural channel flow since the vegetation was the main element of the artificial system. The vegetation, functioning as a sediment filter in the rainy season, is removed in the dry season due to lower flows and evapotranspiration. We understand that vegetation should be addressed as part of the channel management process, providing users with favorable turbidity indices and lower risks of structures breaking, as well as the formation of extenders of fluvial and riparian habitats in the rainy season.

Keywords:
Biogeomorphic Succession; Anthropogeomorphology; Artificial Open Channels; Sedimentation; Hydrogeomorphology