![enter image description here][1] **Summary of Changes from v7 (2023) to v8 (2024)** * Expansion of introduction in Ch. 1 * New map and discussion of global cropland areas added to Ch. 2 * New soil moisture time lapse video added to Section 3.1.2 * New video added to help with soil water retention calculation in Ch. 3 problem set * New video of soil swelling added to Section 4.6 * Changes made to simplify/clarify problems 3 and 4 in Ch. 4 problem set * New video demonstrating soil water balance calculations added to Ch. 5 problem set * New video demonstrating Green-Ampt infiltration calculations added to Ch. 6 problem set * Switched WEPP runoff and erosion problem in Ch. 7 to use WEPPcloud * New “fly-through” video of pore scale solute transport added to Ch. 9 introduction * New video on hydrodynamic dispersion added to Section 9.1.3 * Change to soil textural class in problem 1 of Ch. 10 problem set * Replaced “stomates” with “stomata” throughout Ch. 11 * New video of stoma opening and closing added to Section 11.1 * Added information on water vapor feedback effect in Section 12.4 **Acknowledgements** The development of this textbook was supported in part by the Wise Oklahoma State University Library Open Textbook Initiative and the Oklahoma State Regents for Higher Education Open Educational Resources grant program. The first version of the textbook was begun during the author’s sabbatical at China Agricultural University in 2016, hosted by Dr. Tusheng Ren. Valuable contributions to this book have been made by Jingnuo Dong, Briana Wyatt, and other students and colleagues. Cover Image: Rain and shine near Chilcott, Somerset, UK. Photo by Edmund Shaw. Licensed for reuse CC BY-SA 2.0. Version: 8 Date: January 11, 2024 **About the author** Tyson Ochsner grew up near Chattanooga, Oklahoma, USA, in a farming family, whose history is partly described here ([link][2]). He earned a B.S. in Environmental Science at Oklahoma State University in 1998. He then studied Soil Science and Water Resources under Dr. Robert Horton at Iowa State University earning a M.S. in 2000 and a Ph.D. in 2003. From 2003 through 2008, he worked as a soil scientist for the USDA Agricultural Research Service Soil and Water Management Research Unit in St. Paul, Minnesota, led by Dr. John Baker. Since 2008 he has been a faculty member in the department of Plant and Soil Sciences at Oklahoma State University. The mission of his research and teaching program is to help people better understand and appreciate the soil, the soil water balance, and the surface energy balance so that we can more wisely manage and conserve the land and water with which we have been entrusted. A primary focus of his research has been on multi-scale soil moisture monitoring and improved utilization of soil moisture data in agriculture, meteorology, environmental modeling, and drought adaptation. To learn more about his program, please visit [http://soilphysics.okstate.edu/][3]. A number of educational videos relevant to the content in this book are available at the Oklahoma State University Soil Physics Group YouTube Channel ([link][4]). Tyson and his wife, Stephanie, have six children: Audrey McIntyre (and her husband Taos McIntyre), Isaac, Annelise, Eli, Jameson, and Abel. You can read about one of their family adventures at this blog ([link][5]). [1]: https://files.osf.io/v1/resources/z4rbt/providers/osfstorage/61e8299bbc925b074ed4c59c?mode=render [2]: http://www.ochsnersinamerica.com/ [3]: http://soilphysics.okstate.edu/ [4]: https://www.youtube.com/channel/UC1hb8hm8lzqt21G0OD-i78Q/videos [5]: https://seveninchina.wordpress.com/