In addition to his research activities, Landolt has been involved in numerous botany and nature conservation associations and commissions, such as Pro Natura (formerly the Swiss League for the Protection of Nature), the Zurich and Swiss Botanical Societies, the Naturforschende Gesellschaft in Zürich, the Swiss Greina Foundation for the Conservation of Alpine Rivers, the Sihlwald Nature Conservation Foundation, and the Sitatunga Foundation for Nature Conservation.