National Socio-Environmental Synthesis Center (SESYNC)
1 Park Place, Suite 300
Annapolis, MD 21401
Title: Changing Nutrients, Changing Rivers
Seminar presented by Dr. Carles Ibáñez, Agrifood Research Institute & SESYNC
Abstract: Eutrophication—the excessive enrichment of a body of water with nutrients such as nitrogen (N) and phosphorus (P)—is Earth's most widespread problem for water quality. Growing evidence suggests a global trend toward reversing eutrophication. However, in rivers and estuaries of developed countries and in lakes of emerging economies, the ongoing reduction in nutrient inputs—termed reoligotrophication—is much larger for P than for N. Although the rapid emergence of this phenomenon has hindered detailed monitoring of the ecological effects, a few studies have documented an abrupt shift from green to clear waters and consequently from phytoplankton to macrophytes as dominant primary producers in response to reoligotrophication in rivers and estuaries. However, the improvement in water quality due to P decline does not imply a return to pristine ecological conditions, because high N:P ratios trigger undesirable changes in the ecosystem.
Bio: Dr. Carles Ibáñez is a Senior Researcher at the Department of Marine & Continental Waters of IRTA and former Head of the Department of Aquatic Ecosystems from 2005–2017. He holds a PhD in Biology from the University of Barcelona and completed a postdoc in the Laboratory of Fluvial System Ecology of CNRS (France). He has 30 years of research experience in the field of aquatic, coastal, and wetland ecology, as well as sustainable management of water resources and environmental management, with close to 100 papers published in peer-reviewed international journals. He has been a member of the Advisory Council of Sustainable Use of Water of the Government of Catalonia, and is currently a member of the Advisory Council for Sustainable Development of the same government. He is also a member of the Group of Experts on Climate Change of Catalonia, as well as of the Global Research Alliance on Agricultural Greenhouse Gases. He served as an expert reviewer of the Fifth IPCC Report on Climate Change 2013: Impacts, Adaptation, and Vulnerability (Working Group II), and he is an Associate Editor of the Journal Estuaries & Coasts.