Dr. Mark Nelson is Chairman of the Institute of Ecotechnics, head of Wastewater Gardens International and has worked for several decades in closed ecological system research, bioregenerative space life support, ecological engineering, restoration of damaged ecosystems, desert agriculture and wastewater recycling. Dr. Nelson was a member of the eight person “biospherian” crew for the first two year Biosphere 2 closure experiment, 1991-1993. The project included pioneering regenerative agriculture and waste and water recycling. In the 1970s, he planted an organic fruit orchard at Synergia Ranch, Santa Fe NM and has helped manage its organic fruit and vegetable farm for decades. Mark is an Associate Editor of Life Sciences in Space Research. His books include “Pushing Our Limits: Insights from Biosphere 2” (2018) and “The Wastewater Gardener: Preserving the Planet One Flush at a Time” (2014). A second edition of “Life Under Glass: Crucial Lessons in Planetary Stewardship” written by Mark and two fellow biospherians was just published by Synergetic Press.