Forest restoration has resulted in approximately 300 million ha of restored forests until today. During the second decade of the twenty-first century several international initiatives have sprung up which aim to add 350 million ha of restored forest by 2030. The paper reviews the development of the forest restoration frontier. It tracks trends of the increase of restored forests, emphasizing developments since the second half of the last century. It equally reviews past and ongoing policies, programs, and projects to restore forests. Available data show how the area of restored forests has progressively increased since the 1960s. There are three major objectives to restoring forest: (1) to produce forest products (timber and other products) or spaces for recreation, (2) to produce regulatory ecosystem services (sequestered carbon, erosion control) and (3) to achieve improvement of rural livelihoods. The emphasis on each of these objectives has changed over time and each objective implied different policies and arrangements, involvement of actors and use of technology and know-how. The large international programs and projects since the beginning of the twenty-first century promote forest restoration for biodiversity conservation, regulatory ecosystem services and improving wellbeing of resident populations. Some of the findings related to the development of the forest restoration frontier since the mid-twentieth century suggest that some of the ambitious goals may be unrealistic and result in unwanted outcomes.
Keywords: Biodiversity; Community forestry; Ecosystem services; Forest products; Land cover change; Plantations.
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