Regenerative, semiclosed systems: A priority for twenty-first-century agriculture

This overview draws attention to several reasons to encourage the design of new agronomic systems, shifting from conventional open or leaky systems to more closed, regenerative systems: Current systems cause over consumption of environmental resources, contribute to climate change, rely on increasingly expensive fossil fuel, and result in environmental (e.g., groundwater) contamination. Moreover, the agronomic-urban interface is growing, as are markets for ecologically friendly produce, the need for low-input farming systems in low-income regions, and disenchantment with the subsidization of conventional agriculture. There is reasonable biological and economic evidence to support advocacy for a shift to regenerative systems. Such a shift presents challenges-for example, although higher labor input enhances community well-being and rural social capital, it is costly. It also offers opportunities-for example, to adapt technologies to monitor and minimize wastage. Shifting to semiclosed systems would be accelerated by (a) routine life cycle analysis and costing; (b) calculation of the full costs to society of farm inputs such as pesticides; (c) food labeling and standards that draw attention to energy and other inputs; (d) government grants supporting the transition to semiclosed systems; (e) changing priorities for agronomic research; and (f) greater engagement of urban societies in agriculture through recreation and philanthropy.