A systems approach framework for evaluating tree restoration interventions for social and ecological outcomes in rural tropical landscapes

Fifteen essential science advances needed for effective restoration of the world's forest landscapes

There has never been a more pressing and opportune time for science and practice to collaborate towards restoration of the world's forests. Multiple uncertainties remain for achieving successful, long-term forest landscape restoration (FLR). In this article, we use expert knowledge and literature review to identify knowledge gaps that need closing to advance restoration practice, as an introduction to a landmark theme issue on FLR and the UN Decade on Ecosystem Restoration. Aligned with an Adaptive Management Cycle for FLR, we identify 15 essential science advances required to facilitate FLR success for nature and people. They highlight that the greatest science challenges lie in the conceptualization, planning and assessment stages of restoration, which require an evidence base for why, where and how to restore, at realistic scales. FLR and underlying sciences are complex, requiring spatially explicit approaches across disciplines and sectors, considering multiple objectives, drivers and trade-offs critical for decision-making and financing. The developing tropics are a priority region, where scientists must work with stakeholders across the Adaptive Management Cycle. Clearly communicated scientific evidence for action at the outset of restoration planning will enable donors, decision makers and implementers to develop informed objectives, realistic targets and processes for accountability. This article paves the way for 19 further articles in this theme issue, with author contributions from across the world. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.

Realizing the potential of restoration science

Restoration science is growing fast. The restoration of habitats is increasingly part of the discussion over how to tackle the challenges of climate change, biodiversity loss and rural development. With this increasing role and attendant visibility, restoration science has seen increasing controversy. Here I describe six aspects of robust restoration science that should be kept in mind to help realize its potential: do data-driven studies; focus on robust results; improve reproducibility; contextualize the results; give attention to economics; consider the wider goals of restoration. Realizing the potential of restoration science, via robust scientific studies, will provide society with the knowledge and tools to make better choices about which habitats to restore and where. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.