Influence of catchment processes on fluvial morphology and river habitats

Abstract

Influence of catchment processes on fluvial morphology and river habitatsFluvial morphology is conditioned by three basic elements: flow regime, sediment yield and valley characteristics. These elements are controlled by factors operating at different spatial and time scales, within and outside of the basin. Moreover, the great influence of human activities has to be considered as they presently constitute one of the main hydromorphological factors. This paper synthesises the effects of different variables on fluvial morphology and structures the review around the three basic elements mentioned above with examples from the Iberian Peninsula rivers. Understanding the factors that affect channel morphology is of primary importance for assessing river habitat condition, considering that river reach characteristics are the result of the interaction between upstream and downstream catchment and local conditions. Finally, fluvial geomorphology is a key element in river ecosystems that creates geodiversity and heterogeneity of fluvial forms at different spatial scales (i.e., river habitats) and should be considered part of our natural heritage and a valuable natural element itself.

Análisis multi-temporal de los cambios geomorfológicos y de la cubierta vegetal en un cauce extenso de gravas: el río Cinca, Aragón (España)

“…registrado en las últimas décadas. La dificultad se encuentra en conseguir identificar y valorar las causas de los cambios observados, factores que pueden ser globales, de cuenca y locales, así como una combinación de todos ellos (Ibisate et al, 2011).…”

Landscape Reading for Alpine Rivers: A Case Study from the river Biya

“…The appearance and shape of a natural river result from complex morphological processes and interactions, majorly influenced by geological factors and climatic and hydrological controls (Mahala 2020, Castro and Thorne 2019, Stepinski and Stepinski 2005. These boundary conditions define sediment dynamics and determine the interactions between a river and its surrounding topography (Ibisate et al 2011). Therefore, a profound understanding of a river's geological history is of utmost importance.…”

Bank and point bar morphodynamics in the Lower Jingjiang Reach of the Yangtze River in response to the Three Gorges Project

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