Service crop management to maximize crop water supply and improve agroecosystem resilience: A review

Service crops (commonly known as cover crops) are plants grown in agroecosystems for the ecosystem services they provide rather than a harvestable product. One such service they provide is that of increased crop water supply. By reducing evaporative water loss and increasing soil water storage, storage capacity, and the successive crop's ability to access stored water, service crops may be used to increase agroecosystem resiliency to seasonal water deficits and so improve crop yields. In many instances, however, these benefits are not realized. This is more likely a consequence of suboptimal management, or management tailored to provide other services, rather than the ultimate capacity of service crops to contribute to agroecosystem resilience. After reviewing the literature, we propose that service crop polycultures-in contrast with monocultures-have the greatest potential to provide this service, and that, if properly managed, a grass/legume/taproot service crop mixture could maximize multifunctionality while also offsetting the challenges associated with the component species when grown in monoculture.