How vegetation controls the shape of rivers

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A Sudbury professor has published findings of his study on how vegetation affects the stability and shape of rivers.

Dr. Alessandro Ielpi is an associate professor of sedimentology at the Vale Living with Lakes Centre on Ramsey Lake and the Harquail School of Earth Sciences at Laurentian University in Sudbury.

He published a paper called The impact of vegetation on meandering rivers in the earth and environment section of an online journal called Nature Reviews on Tuesday in collaboration with three professors from two other universities, Stanford and Dalhousie.

The study examines "how vegetation along banks helps rivers bend" and how it relates to flood control.

"To understand how vegetation - or its absence - influences the shape of river channels, Dr. Ielpi and colleagues have canoed through thickly vegetated watersheds, have crossed on foot through barren deserts looking for otherworldly ephemeral streams, and have even looked at the surface of other planets like Mars, where the deposits of billions-year-old meanders are visible through its thin atmosphere," Laurentian University said in a news release.

"Their results demonstrate that although river meanders can form without vegetation, the latter reinforces channel banks, modulating floods and restraining erosion."

Ielpi said the results will help "predict how rivers will behave in a near future if vegetation is continually removed from watersheds through wildfires, aggressive timber harvesting, or urbanization."

"This paper is an example of the scientific, social, and environmental relevance of the study of earth sciences on a planetary and interplanetary scale," Dr. Douglas Tinkam, director of Harquail School of Earth Sciences, said in the news release.

"The authors have published a work that will help scientists and governments to better understand and predict river behaviour, offering valuable research that could help prevent or mitigate flood damage."

Dr. Tammy Eger, Laurentian's vice-president of research, said the study "underscores the importance of international collaborations in scientific discoveries which highlight the healing power of nature."