Global alternatives of natural vegetation cover.

Abstract

Preserving and restoring terrestrial ecosystems is essential to preventing the decline of life on Earth. To guide global conservation efforts, we present a detailed counterfactual map showing Earth's natural tree, short vegetation, and bare ground cover. This map accounts for environmental filtering along with realistic scenarios of fire frequency and wildlife herbivory. The most likely scenario suggests 43% (5669 ± 74 Mha) of land could support trees, 39% (5183 ± 86 Mha) shrubs and grasses, and 18% (2352 ± 59 Mha) bare ground. Adjustments in fire and herbivory could shift a minimum of 675 Mha of land, stressing the importance of considering alternative outcomes when restoring a landscape. Our findings also suggest that adjustments in fire frequency and wildlife herbivory could have a greater impact on natural vegetation than expected climate changes by 2050, highlighting decision-makers' responsibility to guide conservation and restoration toward a sustainable and biodiverse future.