From hydraulics to hydro-morpho-biodynamics: Changes in fluvial studies in the last 50 years

Highlight
• Needed ingredients of rivers are water, sediments and vegetation.
• What we want to know about rivers (science) is not always the same of what we need to do on them (engineering).
• Water-, sediments- and vegetation-dynamics are dealt with, but not altogether explained, by a variety of disciplines.
• River-control, -management and -restoration are the historical 3 phases of river engineering.
• A reasonable mix of holistic and reductionistic approach is the desirable way for both river-science and -engineering.

Large engineering works, devoted to either flood protection or water resources utilization, have been independently built for many centuries with almost exclusive attention to the hydraulic and structural behavior of each single plant. In the last hundred years, however, more comprehensive river management criteria have been developed to prevent disasters and to optimize civil, agricultural and industrial uses. But only since a few decades the impact of human intervention on the fluvial environment is being jointly taken into consideration from the hydrological, morphological and biological point-of-view. The paper discusses the manifold aspects of this recent phase of development, stressing the need for a balanced mix of scientific and practical requirements, of the various disciplines involved and, ultimately, between a reductionist and a holistic approach to the understanding of the river dynamics.