Restriction of Effective Catchment Area by Anthropogenic Elements in a Small Semi-Arid Basin: Preliminary Approaches.

How to analyse fluvial systems with successive interruption elements? The sediment transport dynamics of bedload in non-perennial fluvial systems influenced by various anthropogenic structures have significant potential to experience diverse interferences. Based on this premise, the present study utilises the concept of landscape connectivity, focusing on its structural aspect, to analyse the physical coupling of landscape sections, which becomes more evident in semi-arid fluvial systems with episodic behaviour.This view looks at places that help a lot with a certain outlet using the idea of Effective Catchment Area. This way helps to know watershed behavior by looking at flow events in the channel and the keeping or stopping capacity of the basins. The area chosen for this study is the Riacho Grande watershed, which comes from the lower Piancó River. The basin has water crossings, big dams, and simple dams put here and there throughout its size. The methods used are desk activities using remote sensing tools to find and sort the kinds of human-made structures, then field activities that helped check and grasp the impacts of each type of structure. The findings indicate the extent to which many dams, constructed haphazardly and without any government or water management supervision, extend from the headwater regions to areas near where the main channel of the Piancó River confluences with it. Because these structures interrupt flow, each segment downstream can momentarily function as a fresh source of sediment. In this regard, it raises considerations for long-term effects over decades and how the fluvial system will compensate in terms of either new sediment source areas or reduced capacity to transport sediment due to the constraint on its primary vector for transport (water).