Global change solutions must embrace biodiverse multifunctional planted forests

Abstract

Forests and global changeNatural forests are important habitats for most of the terrestrial biodiversity (plants, animals, microbes, and others) and reservoirs of carbon sequestration that underpin human well-being through the provision of numerous ecosystem services (FAO and UNEP, 2020;Cabon et al., 2022;Malhi et al., 2022). Since 1990, a substantial amount of natural forest has been degraded and even cleared (at a decreasing rate of loss), whereas the area of planted forests has increased by 123 million hectares (FAO, 2020). Human activities and grazing animal disturbances have severely damaged the stability of global natural forest ecosystems (Seidl et al., 2017;Canelles et al., 2021;Lapola et al., 2023). However, pest and pathogen attacks can further decrease biodiversity and stand structural complexity, and alter demographic processes of already human-altered natural forests, thereby negatively impacting overall ecosystem multifunctionality under increasing impacts of global change (Seidl et al., 2017;Canelles et al., 2021). As such, the ability of human-altered natural forest ecosystems to mitigate global warming through carbon sequestration and to maintain a stable provision of many other ecosystem services is threatened by the rise in frequency and severity of wildfires, storms, heat events, floods and droughts (Corlett, 2016; Curtis et al., 2018;Bowd et al., 2019;Lapola et al., 2023). Thus, in response to these impacts, people are planting trees for several different socio-ecological reasons such as forest-based market demands, biodiversity conservation, increasing ecosystem services, improving environmental conditions, promoting socioeconomic conditions, conserving cultural and spiritual values, and legislative requirements (