Domain-specific alliances

Our estimated safe ESB is that around 50–60% of global land surface should be in largely intact, natural condition to halt species extinction, secure biosphere contributions to climate regulation, and stabilise regional water cycles.

from 6–15% in some landscapes (eg, riparian ecosystems, agricultural landscapes with high crop diversity) to 50% in others (eg, in sloping landscapes, or landscapes where erosion or natural hazards are frequent).

The exact area, quality, and spatial configuration required varies by contribution and location, and thus could not be estimated on a global scale, necessitating local translation, assessment of local context, demand for specific NCP, and application of best practices.

10% of natural or semi-natural habitat per km2 is a sharper threshold, below which evidence suggests that many NCP would almost no longer be provided.

safe boundary of at least 20–25% of natural or semi-natural habitat per km2 in human-modified lands (ie, urban and agro-ecosystems) is needed to support both Earth-system NCP and local NCP, in addition to the functions provided by largely intact lands.

human-modified ecosystems, we systematically analysed six critical NCP at local scales

The amount of intact natural land as of 2018 was around 15% below this ESB, but could be increased through restoring degraded ecosystems or previously converted ecosystems,102,103,106102.Strassburg, BBN ∙ Iribarrem, A ∙ Beyer, HL ∙ et al.Global priority areas for ecosystem restorationNature. 2020; 586:724-729CrossrefScopus (536)PubMedGoogle Scholar103.Jung, M ∙ Arnell, A ∙ de Lamo, X ∙ et al.Areas of global importance for conserving terrestrial biodiversity, carbon and waterNat Ecol Evol. 2021; 5:1499-1509CrossrefScopus (162)PubMedGoogle Scholar106.Wolff, S ∙ Schrammeijer, EA ∙ Schulp, CJE ∙ et al.Meeting global land restoration and protection targets: what would the world look like in 2050?Glob Environ Change. 2018; 52:259-272CrossrefScopus (72)Google Scholar with conservation efforts distributed across all ecoregions.

A justice approach, by contrast, requires at least boundaries that minimise significant harm to human health and wellbeing and to other species (panel 2) while ensuring access to necessary resources and services.

this is now quantifying this this safe space but for the first time also doing it for justice so measuring the maximum allowed 00:15:33 of significant harm to people and the key take home here is the following in the outer ring here the red and green you see the safe boundary definitions 00:15:45 the blue lines are the assessment of justice so not surprisingly if we care about people the safe bound is about the stability of the planet but if we care about avoiding significant harm to hundreds of millions of people across 00:15:58 the world the climate boundary shrinks from 1.5 down to one degree