The virtual European Geosciences Union (EGU) general assembly 2021 was started from April 19 to 30, 2021 (CEST). The virtual conference (vEGU21) was held at the virtual conference centre using BigBlueButton (BBB) online live video presentations and discussions with live chat. The theme of this conference focused on “Engage·Discover·Inspire”.

Professor Jun Niu from the College of Water Resources and Civil Engineering in China Agricultural University, Associate Professor Noel Aloysius from the University of Missouri as well as Professor B. Sivakumar from the Indian Institute of Technology Bombay, jointly convened the HS2.1.4 Session (Hydrological processes in agricultural lands under changing environments). A total of 16 abstracts and 14 online materials were received in the Session, which were from University of California, Wageningen University, University of Waterloo, University of Montpellier, Stockholm University, Czech Technical University, University of Missouri, University of Natural Resources and Life Sciences, Aalto University, Austrian Research Center Forests, University of Hohenheim, Universiti Putra Malaysia, Centre d’Etudes Spatiales de la Biosphère, as well as China Agricultural University and Guangzhou University.

The HS2.1.4 Session was held on April 26 from 9:00-10:30 (CEST). The presenters were required to upload their presentation materials (Slides, Poster, etc.) 24 hours before the Session’s start, and the EGUHost will display the materials according to the sequence arranged by the convener when presenters making live video reports. Fourteen professors or scholars from 11 countries including China, Canada, the United States of America, Austria, the Czech Republic, Finland, France, Germany, the Netherlands, Sweden, and Malaysia gave presentations. The content of the meeting covered hydrological functioning of irrigated maize crops in southwestern France, hydrological response mechanisms of California’s largest lake, changes of Mulberry-based fish ponds in the Guangdong-Hong Kong-Macao Greater Bay Area, changing balance between the flow regime and the agricultural practices in the Mekong delta, response of the nitrogen and phosphorus use efficiencies to climate change, effects of agricultural conservation practices on the local water cycle, soil moisture dynamics in agricultural landscapes under varying weather patterns, response of crop evapotranspiration under increased carbon dioxide, discrepancies and uncertainties of soil content sensors, effects of the use of drainage-/infiltration systems in the uplands of the Netherlands, impact of winter soil processes on nutrient leaching in cold region agroecosystems, response of groundwater level and water balance to controlled drainage in future scenarios, runoff response after heavy rainfall events in a small watershed, historical and projected future hydroclimatic risk on yield in the irrigated rice paddies of Malaysia, showing the latest research progress on hydrological processes in agricultural lands under changing environments from different perspectives. Dehai Liao, a graduate student from the College of Water Resources and Civil Engineering, conducted an online report about the response of crop water consumption in the northwest agricultural region under future scenarios. After the oral report, Professor Jun Niu made a summary of the presentations, and then all the participants conducted more in-depth discussions through the chatbox, and formed 226 discussion records eventually, through the frequent online interactions.