Land use is central to addressing sustainability issues, including biodiversity conservation, climate change,
food security, poverty alleviation, and sustainable energy. In this paper, we synthesize knowledge accumulated in land system science, the integrated study of terrestrial social-ecological systems, into 10 hard
truths that have strong, general, empirical support. These facts help to explain the challenges of achieving
sustainability in land use and thus also point toward solutions. The 10 facts are as follows: 1) Meanings and
values of the land are socially constructed and contested; 2) land systems exhibit complex behaviors with
abrupt, hard-to-predict changes; 3) irreversible changes and path dependence are common features of
land systems; 4) some land uses have a small footprint but very large impacts; 5) drivers and impacts of
land-use change are globally interconnected and spill over to distant locations; 6) humanity lives on a used
planet where all land provides benefits to societies; 7) land-use change usually entails trade-offs between
different benefits—”win-wins” are thus rare; 8) land tenure and land-use claims are often unclear, overlapping, and contested; 9) the benefits and burdens from land are unequally distributed, and 10) land users
have multiple, sometimes conflicting, ideas of what social and environmental justice entails. The facts have
implications for governance but do not provide fixed answers. Instead, they constitute a set of core principles that can guide scientists, policymakers, and practitioners toward meeting sustainability challenges
in land use.
