Boom and bust carbon-nitrogen dynamics during reforestation

Gabriel G. Katul received his B.E. degree in 1988 at the American University of Beirut (Beirut, Lebanon), his M.S. degree in 1990 at Oregon State University (Corvallis, OR) and his Ph.D degree in 1993 at the University of California in Davis (Davis, CA).  He currently holds a distinguished Professorship in Hydrology and Micrometeorology at the Department of Civil and Environmental Engineering at Duke University (Durham, NC).   He was a visiting fellow at University of Virginia (USA) in 1997, the Commonwealth Science and Industrial Research Organization (Australia) in 2002, the University of Helsinki (Finland) in 2009,  the FulBright-Italy Distinguished Fellow at Politecnico di Torino (Italy) in 2010, the École polytechnique fédérale de Lausanne (Switzerland) in 2013,  Nagoya University (Japan) in 2014, University of Helsinki (Finland) in 2017, the Karlsruher Institute for Technology (Germany) in 2017, Princeton University (USA) in 2020, and CzechGlobe (Brno - Czech Republic) in 2023. He received several honorary awards, including the inspirational teaching award by the students of the School of the Environment at Duke University (in 1994 and 1996), an honorary certificate by La Seccion de Agrofisica de la Sociedad Cubana de Fisica in Habana (in 1998), the Macelwane medal and became thereafter a fellow of the American Geophysical Union (in 2002), the editor’s citation for excellence in refereeing from the American Geophysical Union (in 2008), the Hydrologic Science Award from the American Geophysical Union (in 2012), the John Dalton medal from the European Geosciences Union (in 2018), the Outstanding Achievements in Biometeorology Award from the American Meteorological Society (in 2021) and later became an elected fellow of the American Meteorological Society (in 2024), and the recipient of the American Meteorological Society hydrologic science medal (in 2025).  Katul was elected to the National Academy of Engineering (in 2023) for his contributions in eco-hydrology and environmental fluid mechanics.  He served as the Secretary General for the Hydrologic Science Section at the American Geophysical Union (2006-2008).  His research focuses on micro-meteorology and near-surface hydrology with emphasis on heat, momentum, carbon dioxide, water vapor, ozone, particulate matter (including aerosols, pollen, and seeds) and water transport in the soil-plant-atmosphere system as well as their implications to a plethora of hydrological, ecological, atmospheric and climate change related problems.

Richter’s research and teaching links soils with ecosystems and the wider environment, most recently Earth scientists’ Critical Zone.  He focuses on how humanity is transforming Earth’s soils from natural to human-natural systems, specifically how land-uses alter soil processes and properties on time scales of decades, centuries, and millennia.  Richter's book, Understanding Soil Change (Cambridge University Press), co-authored with his former PhD student Daniel Markewitz (Professor at University of Georgia), explores a legacy of soil change across the Southern Piedmont of North America, from the acidic soils of primary hardwood forests that covered the region until 1800, through the marked transformations affected by long-cultivated cotton, to contemporary soils of rapidly growing and intensively managed pine forests.  Richter and colleagues work to expand the concept of soil as the full biogeochemical weathering system of the Earth’s crust, ie, the Earth’s belowground Critical Zone, which can be tens of meters deep.  The research examines decadal to millennial changes in the chemistry and cycling of soil C, N, P, Ca, K, Mg, and trace elements B, Fe, Mn, Cu, Be, Zr, and Zn across full soil profiles as deep at 30-m.  Since 1988, Richter has worked at and directed the Long-Term Calhoun Soil-Ecosystem Experiment (LTSE) in the Piedmont of South Carolina, a collaborative study with the USDA Forest Service that quantifies how soils form as natural bodies and are transformed by human action, and a study that has grown to become an international model for such long-term soil and ecosystem studies.  In 2005, Richter and students initiated the first comprehensive international inventory project of the world’s LTSEs, using an advanced-format website that has networked metadata from 250 LTSEs.  The LTSEs project has held three workshops at Duke University, NCSU's Center for Environmental Farming Systems, and the USDA Forest Service's Calhoun Experimental Forest and Coweeta Hydrologic Laboratory, hosting representatives from Africa, Asia, Australia, Europe, and the Americas.  Richter's 60-year old Long Term Calhoun Soil and Ecosystem Experiment is linked to similar experiments and platforms around the world via the ‘Long-Term Soil-Ecosystem Experiments Global Inventory’, assembled by Dan Richter, Pete Smith, and Mike Hofmockel."He is an active member of the International Commission on Stratigraphy’s Working Group on the Anthropocene.  Richter has written in the peer-reviewed literature about all of these projects, and in November 2014 his soils research at the Calhoun and his soils teaching were featured in Science magazine.