Mapping the planet’s critical areas for biodiversity and nature’s contributions to people

The paper addresses how to jointly meet global biodiversity, climate, and sustainable development commitments by identifying places where nature’s contributions to people (NCP) and terrestrial biodiversity co-occur, and where these priorities intersect with pressures for economic development. Rapid ecosystem transformation and climate change are diminishing biodiversity and NCP, even as nations commit to conserving at least 30% of lands and waters by 2030 (Global Biodiversity Framework) and some propose conserving 50% of land (“Half-Earth”). The study’s purpose is to map global priorities for safeguarding multiple NCP alongside terrestrial vertebrate biodiversity and to quantify how much and which land is required to achieve these targets. It also evaluates potential conflicts by overlaying priority areas with development potential (agriculture, energy, mining, oil and gas, urban expansion) and assesses the extent to which current protected areas and OECMs already cover these priorities.

The study builds on prior global efforts to identify biodiversity hotspots and assess the sufficiency of protected area networks for biodiversity representation, as well as recent global modeling of NCP and irrecoverable carbon stocks. It integrates strands of literature on spatial conservation prioritization, minimum-area targets for safeguarding biodiversity, and development pressure mapping across sectors (e.g., renewable energy, fossil fuels, mining, and agriculture). The authors note that, while biodiversity representation in protected areas has been widely studied, joint prioritization of NCP and species, and their overlap with development potential, has been less explored at a global scale.

• Scope and features: The analysis jointly prioritizes ten NCP and terrestrial biodiversity (area of habitat, AOH) for 26,709 vertebrate species (10,774 birds; 5,219 mammals; 4,462 reptiles; 6,254 amphibians). NCP include: vulnerable ecosystem carbon storage (global benefit) and nine locally/regionally realized NCP—coastal risk reduction, flood regulation, sediment retention, nitrogen retention for water quality, crop pollination, fodder production for livestock (including grazing), fuelwood production, timber production, and access to nature. NCP values are realized as benefits and, where possible, weighted by beneficiaries (e.g., downstream populations, people protected from coastal storms, or within one hour travel of nature).
• NCP modeling: Vulnerable carbon mapped as above- and below-ground carbon likely lost in a typical disturbance; coastal protection, sediment retention, nitrogen retention, and pollination modeled with InVEST adapted for global application; fodder, timber, and fuelwood with Co$ting Nature v3; access to nature estimated as population within one hour of natural/semi-natural habitats over a friction surface. NCP attributed to natural and semi-natural land cover (excluding urban/developed and unvegetated classes); Antarctica excluded.
• Biodiversity data (AOH): Species ranges derived from IUCN/BirdLife polygons filtered to extant range, rasterized at ~1 km (Eckert IV), refined by species-specific habitat associations (matched to ESA 2018 land cover) and elevational limits (WorldClim/SRTM). For birds, seasonal ranges were processed separately. AOH aims to better approximate actual occurrence than EOO.
• Spatial optimization: Minimum set reserve selection using linear programming with prioritizr (R) and Gurobi. Targets for NCP set across 19 levels (5–95% in 5% increments). Species representation targets set as a function of AOH area: 10–100% targets (with a cap of 1,000,000 km² for wide-ranging species), ensuring both restricted-range and wide-ranging species are represented; species targets were held constant across scenarios. Objective minimized total selected area (used in place of minimum cost due to cost data limitations). Due to computational limits (20M+ planning units, 26k+ features), contiguity constraints were not used.
• Resolutions and masking: NCP-only optimizations run globally at up to 2 km resolution; combined NCP+species optimizations at 10 km, then masked to natural/semi-natural habitat at 2 km to align with NCP-only outputs and better identify habitat providing NCP.
• Protected areas/OECMs: WDPA and WDOECM used to quantify coverage of prioritized areas and to run scenarios with PAs/OECMs “locked-in” to assess additional land needed beyond current conservation estate (marine areas excluded; data cleaned and reprojected to equal-area CRS).
• Development pressure: Overlaid prioritized areas with Development Potential Indices (DPIs) for 14 sector layers (renewable energy types, oil and gas, mining types, commercial agriculture) and a derived Urban Pressure Index. DPIs standardized by country (z-scores) and classified into six pressure categories; a composite map identified locations of high/very high development potential and sector-specific overlaps.
• Analyses: Computed land area needed to reach NCP and species targets under different scenarios, quantified overlap with PAs/OECMs, and measured overlap with high development potential by sector and across continents/biomes.

• Area needed for joint goals: Conserving 44% of global land (excluding Antarctica) could provide 90% of current NCP and meet minimum representation targets for 26,709 terrestrial vertebrate species, if spatially optimized and coordinated. Locking in current PAs/OECMs increases the requirement to 49% of global land to achieve the same targets.
• NCP-only: Achieving 90% of NCP without species targets would require 36% of global land. There is substantial spatial overlap between NCP and biodiversity priorities, enabling synergies.
• Coverage by existing conservation: Only 18% of prioritized areas for NCP and biodiversity are currently protected (WDPA/OECM). Achieving 90% of NCP plus species targets would require conserving or sustainably managing an additional 34% of land beyond current PAs/OECMs (total 49%).
• Development conflicts: 37% of prioritized areas have high development potential in at least one of five sectors, equivalent to 16% of global land area. Only 11% of such overlapping areas are currently protected, indicating elevated risk of conflict. • Sector overlaps with prioritized areas: Renewable energy overlaps 10% of prioritized areas (≈4% of global land); agriculture 7% (≈3% global); mining 6% (≈3% global); oil and gas 5% (≈2% global); urban expansion also contributes to overlaps.
• Geographic patterns: Priority areas include species-rich and high-NCP regions such as the Amazon and Congo basins, Papua New Guinea/Indonesia, southeastern Australia, the Himalayas, Andes, New Zealand, eastern Madagascar, Caribbean islands, Central American montane regions, western India, parts of Oceania, western Europe, and the Yangtze basin. Some arid and high-latitude regions are highlighted mainly by species targets rather than NCP.
• Continental/country patterns of overlap with development: Overlap between prioritized areas and high development potential spans 31% of Oceania’s land, 25% South America, 23% Europe, 20% North America, 17% Africa, and 11% each in Australia and Asia. Countries with more than half their land in globally prioritized areas with high development potential include Gambia (63%), Ireland (60%), and Jamaica (53%).
• Implications for 30% target: If optimally allocated, conserving 30% of land could represent areas supplying 65% of current NCP while meeting species targets; when current PAs/OECMs are locked in, 30% would supply only 45% of NCP while meeting species targets.

The analysis demonstrates that substantial synergies are possible between conserving biodiversity and maintaining NCP, with optimized configurations enabling 90% of current NCP provision alongside meeting species representation targets on approximately 44% of land. However, existing protected areas/OECMs are insufficiently placed to achieve these joint goals efficiently; locking them in raises area requirements to 49%. These results support global commitments such as conserving at least 30% of land by 2030 and provide quantitative evidence relevant to proposals advocating conservation of half the Earth. A major challenge is the significant overlap between globally prioritized areas and high development potential, particularly for renewable energy and agriculture. This highlights the need for integrated, cross-sectoral planning to site development (e.g., renewables, agriculture, urban growth) on previously converted or degraded lands to minimize conflicts and to design projects that maintain or enhance NCP. Aligning conservation with development requires coordination across scales: while the priorities are globally identified, implementation must incorporate national and local information on feasibility, costs, governance, and the rights and preferences of Indigenous peoples and local communities. The study further shows that meeting an area-based 30% target does not guarantee safeguarding a commensurate share of NCP under current PA/OECM configurations (about 45% of NCP), underscoring the importance of strategic placement. The findings thus address the central research question by quantifying how much and where land conservation is needed to jointly meet NCP and biodiversity goals, while revealing where development pressures may jeopardize these outcomes and where planning could mitigate trade-offs.

This work provides the most comprehensive global integration to date of NCP, terrestrial vertebrate biodiversity (AOH), and multi-sector development potential to identify priority areas for conservation and sustainable management. It shows that strategically conserving about 44% of land can maintain 90% of current NCP and meet species representation targets, with current PAs/OECMs requiring expansion or complementary measures to reach these goals. The results support international targets (e.g., conserving at least 30% by 2030) and inform the case for more ambitious conservation. Future research should: incorporate additional taxa (e.g., plants, invertebrates), marine and freshwater priorities; include ecological processes (connectivity, traits, evolutionary history) and genetic diversity; improve NCP modeling and beneficiary data; use higher spatial resolutions and contiguity constraints as computational capacity grows; and account for climate, population, and consumption changes to anticipate shifting NCP demand and species distributions. Continued development of development-pressure datasets and scenario analyses will further refine where conservation and development can be most compatible.

• Data scope: Biodiversity limited to terrestrial vertebrates; plants and invertebrates not included. NCP set excludes some services and assumes low/no NCP in sparsely vegetated and heavily modified landscapes, potentially underrepresenting benefits in deserts or agro-ecosystems.
• Representation targets: Species targets are minimums based on AOH area and do not incorporate connectivity, species traits, ecological interactions, evolutionary processes, ecosystem representation, or genetic diversity.
• Spatial and computational constraints: Combined NCP+species optimizations run at 10 km and masked to 2 km; contiguity constraints were not applied; results may include fragmented priority selections and may differ at finer resolutions.
• Development pressure estimates: DPIs/UPI reflect suitability and macro-scale patterns; they may over- or under-estimate actual future development due to shifting demands, policies, and economic conditions.
• Protected area configuration: Lock-in scenarios reflect current PA/OECM placement, which may be biased and suboptimal relative to joint NCP-biodiversity objectives.
• Generalization: Global results provide a strategic starting point; implementation requires local data on feasibility, costs, governance, and respect for Indigenous and local community rights and preferences.