The second green revolution: Innovative urban agriculture's contribution to food security and sustainability - A review

Since 2010, advances in scientific knowledge and innovative agricultural technology have revitalized urban agriculture (UA) into innovative urban agriculture (IUA). The continuous intensification of IUA could lead to a Second Green Revolution, which aims to meet the current and future food demand. Here, we review the emerging IUA practices and estimate the contribution of IUA to food security and environmental sustainability by limitedly comparing scientific literature and actual data of eighteen practitioners worldwide. The currently most productive IUA practice can produce up to 140 kg vegetables per m(2)/year. Various scales of IUA potentially contribute to global food security by supporting local food supply, strengthening the food value chain, and applying more sustainable practices than conventional agriculture. Further comprehensive life cycle assessments of IUA are needed, especially in developing countries, to prevent an increase of the environmental burden and to balance the interests of people, planet, and profit.