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“Reflections on Rivers: Some Reminiscences and Results from Forty Years of River Research” is the title of a talk given by Jacob Bendix, professor of geography and the environment, Maxwell School of Citizenship and Public Affairs at Syracuse University, for 2024’s Gould Lecture. Professor Bendix summarized the talk as an attempt to illustrate some of the complex ways in which rivers interact with their surrounding environment. 

Professor Bendix took a narrative approach, following the development of some of his own thinking and specific examples focus on rivers, riparian vegetation, and wildfire in California. Starting from his academic history in fluvial geomorphology, geomorphology, and his interest in the interaction between vegetation and landforms, Professor Bendix talked about an early project to try to determine if summer storms affected erosion along a streambank. Talking with locals, he learned that the stream was intentionally plowed out to deliver more rain downstream. A fuller picture emerged, and it was both these factors that could have caused the extra erosion.

A recurring point is understanding the rivers and then trying to see how that environment and associated vegetation are affected by fire and how frequently, as different vegetation affects the soils differently, in direct and indirect ways. For example, fire burns chaparral directly but then the chaparral secretes a hydrophobic layer in the subsurface when burned. This hydrophobic layer prevents the soils from absorbing heavy rains and leads to more landslides, which lead in turn to the growth of different types of vegetation.   

In another study, where the riparian vegetation burned approximately every 75 years, Professor Bendix observed that most species resprouted except the dominant species, leading to compositional change of the vegetation around the river. Surprisingly, distance from the stream seemed irrelevant and led to the conclusion that fire homogenizes the vegetation around the river. The study was periodic and could not contain the entire lifecycle of all the vegetation and changes of the drainage basin and the climate. Time must therefore be considered in a study — the duration to achieve various levels of vegetation growth and the timing of observations relative to growth and fire (re-)occurrence.

To paraphrase Professor Bendix, it is the interactions of many things in the cycle that cause the changes we can only see in brief flashes of time.

Professor Bendix earned degrees in geography from the universities of California–Berkeley, Wisconsin–Madison, and Georgia, with employment in between as a bookseller, house painter, and wildland firefighter, before teaching two years at Georgia and 29
years at Syracuse University. His research interests focus on the often overlapping realms of fluvial geomorphology, riparian ecology, and pyrogeography.