Seeding or planting to revegetate the world's degraded land: systematic review and experimentation to address methodological issues

Abstract

Revegetation is key to achieve the goals of the UN Decade on Ecosystem Restoration. For many situations and plant species, selecting direct seeding or planting can define revegetation success. However, there is no clarity about when one method should be preferred over the other, partly driven by methodological difficulties that preclude avoiding bias during experimentation. To move the debate forward, (1) we propose a systematic review of the studies that compare seeding and planting, including how they have handled bias; and (2) we describe an ongoing experiment that tests different ways to handle bias when comparing seeding with planting.