AUTHOR=Hein T. , Infante D. M. , Schinegger R. , Schoelynck J. , Weigelhofer G. TITLE=Editorial: Challenges and Innovative Solutions in River Sciences JOURNAL=Frontiers in Environmental Science VOLUME=9 YEAR=2021 URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2021.655473 DOI=10.3389/fenvs.2021.655473 ISSN=2296-665X