Before revision: On land The use of swales has been popularized as a rainwater-harvesting and soil-conservation strategy by Bill Mollison (1928-2016) , David Holmgren (1955- ) , and other advocates of permaculture.
After revision: On land The use of swales has been popularized as a rainwater-harvesting and soil-conservation strategy by Bill Mollison , David Holmgren , and other advocates of permaculture.