Excessive and destructive accumulation of water from abnormal, prolonged periods of above-average precipitation or from the rising of waterways that impact communities, livelihoods, ecosystems, and infrastructure.

Icon

Protect Grasslands & Savannas

Image
Image
Boreal grassland
Coming Soon
On
Summary

This solution focuses on the legal protection of grassland and savanna ecosystems through the establishment of protected areas (PAs), which are managed with the primary goal of conserving nature and land tenure for Indigenous peoples. These protections reduce grassland degradation, which preserves carbon stored in soils and vegetation and enables continued carbon sequestration by healthy grasslands.

This solution only includes non-coastal grasslands and savannas on mineral soils in areas that do not naturally support forests. Salt marshes are included in the Protect Coastal Wetlands solution, grasslands on peat soils are included in the Protect Peatlands solution, grasslands that are the product of deforestation are included in the Restore Forests solution, and grasslands that have been converted to other uses are included in the Restore Grasslands and Savannas solution.

Description for Social and Search
The Protect Grasslands & Savannas solution is coming soon.
Overview

Grasslands, also called steppes (Europe and Asia), pampas (South America), and prairies (North America), are ecosystems dominated by herbaceous plants that have relatively low tree or shrub cover. Savannas are ecosystems characterized by low-density tree cover that allows for a grass subcanopy (Bardgett et al., 2021; Parente et al., 2024). Grasslands and savannas span arid to mesic climates from the tropics to the tundra; many depend on periodic fires and grazing by large herbivores. The dataset used to define grassland extent for this analysis classifies areas with sparse vegetation, including some deserts and tundra, as grasslands (Parente et al., 2024), but excludes planted and intensively managed livestock pastures. Hereafter we refer to all of these ecosystems, including savannas, as “grasslands.” 

Historically, grasslands covered up to 40% of global land area, depending on the definition used (Bardgett et al., 2021; Parente et al., 2024; Suttie et al., 2005). An estimated 46% of temperate grasslands and 24% of tropical grasslands have been converted to cropland or lost to afforestation or development (Hoekstra et al., 2004). Nearly half of remaining grasslands are estimated to be degraded due to over- or undergrazing, woody plant encroachment, climate change, invasive species, addition of fertilizers or legumes for forage production, and changing fire regimes (Bardgett et al., 2021; Briggs et al., 2005; Gang et al., 2014; Ratajczak et al., 2012). 

Grasslands store carbon primarily in soils and below-ground biomass (Bai & Cotrufo, 2022). A large fraction of the carbon that grasses take up is allocated to root growth, which over time is incorporated into soil organic matter (Bai & Cotrufo, 2022). When native vegetation is removed and land is tilled to convert grasslands to croplands, carbon from biomass and soils is lost as CO₂.  

Estimates of total carbon stocks in grasslands range from 388–1,257 Gt CO₂‑eq (Conant et al., 2017; Goldstein et al., 2020; Poeplau, 2021). Soil carbon generally persists over long timescales and takes decades to rebuild, with one study estimating that 132 Gt CO₂‑eq in grasslands is vulnerable to loss, and that 25 Gt CO₂‑eq of that would be irrecoverable over a 30-year timeframe (Goldstein et al., 2020). Our analysis did not quantify the impacts of grazing or woody plant encroachment on grassland carbon stocks, which can be mixed, though grazing is discussed further in the Improve Livestock Grazing solution (Barger et al., 2011; Conant et al., 2017; Jackson et al., 2002; Stanley et al., 2024). 

Long-term legal protection of grasslands through PAs and Indigenous peoples’ land tenure reduces conversion and therefore avoids conversion-related pulses of GHG emissions from plowing soils and removing biomass. We consider grasslands to be protected if they are 1) formally designated as PAs (UNEP-WCMC and IUCN, 2024), or 2) mapped as Indigenous peoples’ lands (IPLs) by Garnett et al. (2018) (Appendix). PAs vary in their allowed uses, ranging from strict wilderness preserves to sustainable-use areas that allow for some natural resource extraction; all levels were included in this analysis (UNEP-WCMC and IUCN, 2024). 

IPLs and PAs reduce, but do not eliminate, ecosystem loss (Baragwanath et al., 2020; Blackman & Viet 2018; Li et al., 2024; McNicol et al., 2023; Sze et al. 2022; Wolf et al., 2023; Wade et al., 2020). Improving management to further reduce land use change within PAs and ensure ecologically appropriate grazing and fire regimes is a critical component of grassland protection (Jones et al., 2018; Meng et al., 2023; Vijay et al., 2018; Visconti et al., 2019; Watson et al., 2014). Additionally, market-based strategies and other policies can complement legal protection by reducing incentives for grassland conversion (e.g., Garett et al., 2019; Golub et al., 2021; Heilmayr et al., 2020; Lambin et al., 2018; Levy et al., 2023; Macdonald et al., 2024; Marin et al., 2022; Villoria et al., 2022; West et al., 2023). Our analyses are based on legal protection because the effectiveness of market-based strategies is difficult to quantify, but these strategies will be further discussed in an additional appendix (coming soon).

Adams, V. M., Iacona, G. D., & Possingham, H. P. (2019). Weighing the benefits of expanding protected areas versus managing existing ones. Nature Sustainability2(5), 404–411. https://doi.org/10.1038/s41893-019-0275-5

Ahlering, M., Fargione, J., & Parton, W. (2016). Potential carbon dioxide emission reductions from avoided grassland conversion in the northern Great Plains. Ecosphere7(12), Article e01625. https://doi.org/10.1002/ecs2.1625

Asamoah, E. F., Beaumont, L. J., & Maina, J. M. (2021). Climate and land-use changes reduce the benefits of terrestrial protected areas. Nature Climate Change11(12), 1105–1110. https://doi.org/10.1038/s41558-021-01223-2

Bai, Y., & Cotrufo, M. F. (2022). Grassland soil carbon sequestration: Current understanding, challenges, and solutions. Science377(6606), 603–608. Link to source: https://doi.org/10.1126/science.abo2380

Baragwanath, K., & Bayi, E. (2020). Collective property rights reduce deforestation in the Brazilian Amazon. Proceedings of the National Academy of Sciences117(34), 20495–20502. https://doi.org/10.1073/pnas.1917874117

Bardgett, R. D., Bullock, J. M., Lavorel, S., Manning, P., Schaffner, U., Ostle, N., Chomel, M., Durigan, G., L. Fry, E., Johnson, D., Lavallee, J. M., Le Provost, G., Luo, S., Png, K., Sankaran, M., Hou, X., Zhou, H., Ma, L., Ren, W., … Shi, H. (2021). Combating global grassland degradation. Nature Reviews Earth & Environment2(10), 720–735. https://doi.org/10.1038/s43017-021-00207-2

Barger, N. N., Archer, S. R., Campbell, J. L., Huang, C., Morton, J. A., & Knapp, A. K. (2011). Woody plant proliferation in North American drylands: A synthesis of impacts on ecosystem carbon balance. Journal of Geophysical Research: Biogeosciences116(G4), Article G00K07. https://doi.org/10.1029/2010JG001506

Barnes, M. D., Glew, L., Wyborn, C., & Craigie, I. D. (2018). Prevent perverse outcomes from global protected area policy. Nature Ecology & Evolution2(5), 759–762. https://doi.org/10.1038/s41559-018-0501-y

Bengtsson, J., Bullock, J. M., Egoh, B., Everson, C., Everson, T., O’Connor, T., O’Farrell, P. J., Smith, H. G., & Lindborg, R. (2019). Grasslands—More important for ecosystem services than you might think. Ecosphere10(2), Article e02582. https://doi.org/10.1002/ecs2.2582

Berg, A., & McColl, K. A. (2021). No projected global drylands expansion under greenhouse warming. Nature Climate Change11(4), 331–337. https://doi.org/10.1038/s41558-021-01007-8

Blackman, A., & Veit, P. (2018). Titled Amazon Indigenous communities cut forest carbon emissions. Ecological Economics153, 56–67. https://doi.org/10.1016/j.ecolecon.2018.06.016

Briggs, J. M., Knapp, A. K., Blair, J. M., Heisler, J. L., Hoch, G. A., Lett, M. S., & McCarron, J. K. (2005). An ecosystem in transition: Causes and consequences of the conversion of mesic grassland to shrubland. BioScience55(3), 243–254. https://doi.org/10.1641/0006-3568(2005)055[0243:AEITCA]2.0.CO;2

Bruner, A. G., Gullison, R. E., & Balmford, A. (2004). Financial costs and shortfalls of managing and expanding Protected-Area systems in developing countries. BioScience54(12), 1119–1126. https://doi.org/10.1641/0006-3568(2004)054[1119:FCASOM]2.0.CO;2

Carbutt, C., Henwood, W. D., & Gilfedder, L. A. (2017). Global plight of native temperate grasslands: Going, going, gone? Biodiversity and Conservation26(12), 2911–2932. https://doi.org/10.1007/s10531-017-1398-5

Chang, J., Ciais, P., Gasser, T., Smith, P., Herrero, M., Havlík, P., Obersteiner, M., Guenet, B., Goll, D. S., Li, W., Naipal, V., Peng, S., Qiu, C., Tian, H., Viovy, N., Yue, C., & Zhu, D. (2021). Climate warming from managed grasslands cancels the cooling effect of carbon sinks in sparsely grazed and natural grasslands. Nature Communications12(1), Article 118. https://doi.org/10.1038/s41467-020-20406-7

Conant, R. T., Cerri, C. E. P., Osborne, B. B., & Paustian, K. (2017). Grassland management impacts on soil carbon stocks: A new synthesis. Ecological Applications27(2), 662–668. https://doi.org/10.1002/eap.1473

Craine, J. M., Ocheltree, T. W., Nippert, J. B., Towne, E. G., Skibbe, A. M., Kembel, S. W., & Fargione, J. E. (2013). Global diversity of drought tolerance and grassland climate-change resilience. Nature Climate Change3(1), 63–67. https://doi.org/10.1038/nclimate1634

Dinerstein, E., Joshi, A. R., Hahn, N. R., Lee, A. T. L., Vynne, C., Burkart, K., Asner, G. P., Beckham, C., Ceballos, G., Cuthbert, R., Dirzo, R., Fankem, O., Hertel, S., Li, B. V., Mellin, H., Pharand-Deschênes, F., Olson, D., Pandav, B., Peres, C. A., … Zolli, A. (2024). Conservation Imperatives: Securing the last unprotected terrestrial sites harboring irreplaceable biodiversity. Frontiers in Science2. https://doi.org/10.3389/fsci.2024.1349350

Feng, S., & Fu, Q. (2013). Expansion of global drylands under a warming climate. Atmospheric Chemistry and Physics13(19), 10081–10094. https://doi.org/10.5194/acp-13-10081-2013

Gang, C., Zhou, W., Chen, Y., Wang, Z., Sun, Z., Li, J., Qi, J., & Odeh, I. (2014). Quantitative assessment of the contributions of climate change and human activities on global grassland degradation. Environmental Earth Sciences72(11), 4273–4282. https://doi.org/10.1007/s12665-014-3322-6

Garnett, S. T., Burgess, N. D., Fa, J. E., Fernández-Llamazares, Á., Molnár, Z., Robinson, C. J., Watson, J. E. M., Zander, K. K., Austin, B., Brondizio, E. S., Collier, N. F., Duncan, T., Ellis, E., Geyle, H., Jackson, M. V., Jonas, H., Malmer, P., McGowan, B., Sivongxay, A., & Leiper, I. (2018). A spatial overview of the global importance of Indigenous lands for conservation. Nature Sustainability1(7), 369–374. https://doi.org/10.1038/s41893-018-0100-6

Garrett, R. D., Levy, S., Carlson, K. M., Gardner, T. A., Godar, J., Clapp, J., Dauvergne, P., Heilmayr, R., le Polain de Waroux, Y., Ayre, B., Barr, R., Døvre, B., Gibbs, H. K., Hall, S., Lake, S., Milder, J. C., Rausch, L. L., Rivero, R., Rueda, X., … Villoria, N. (2019). Criteria for effective zero-deforestation commitments. Global Environmental Change54, 135–147. https://doi.org/10.1016/j.gloenvcha.2018.11.003

Goldstein, A., Turner, W. R., Spawn, S. A., Anderson-Teixeira, K. J., Cook-Patton, S., Fargione, J., Gibbs, H. K., Griscom, B., Hewson, J. H., Howard, J. F., Ledezma, J. C., Page, S., Koh, L. P., Rockström, J., Sanderman, J., & Hole, D. G. (2020). Protecting irrecoverable carbon in Earth’s ecosystems. Nature Climate Change10(4), 287–295. https://doi.org/10.1038/s41558-020-0738-8

Golub, A., Herrera, D., Leslie, G., Pietracci, B., & Lubowski, R. (2021). A real options framework for reducing emissions from deforestation: Reconciling short-term incentives with long-term benefits from conservation and agricultural intensification. Ecosystem Services49, Article 101275. https://doi.org/10.1016/j.ecoser.2021.101275

Graham, V., Geldmann, J., Adams, V. M., Negret, P. J., Sinovas, P., & Chang, H.-C. (2021). Southeast Asian protected areas are effective in conserving forest cover and forest carbon stocks compared to unprotected areas. Scientific Reports11(1), Article 23760. https://doi.org/10.1038/s41598-021-03188-w

Grasslands, Rangelands, Savannahs and Shrublands (GRaSS) Alliance. (2023). Valuing Grasslands: Critical ecosystems for nature, climate, and people [Discussion paper]. Link to source: https://www.birdlife.org/wp-content/uploads/2023/12/Valuing-Grasslands-Report-Dec-2023.pdf

Griscom, B. W., Adams, J., Ellis, P. W., Houghton, R. A., Lomax, G., Miteva, D. A., Schlesinger, W. H., Shoch, D., Siikamäki, J. V., Smith, P., Woodbury, P., Zganjar, C., Blackman, A., Campari, J., Conant, R. T., Delgado, C., Elias, P., Gopalakrishna, T., Hamsik, M. R., … Fargione, J. (2017). Natural climate solutions. Proceedings of the National Academy of Sciences114(44), 11645–11650. https://doi.org/10.1073/pnas.1710465114

Heilmayr, R., Rausch, L. L., Munger, J., & Gibbs, H. K. (2020). Brazil’s Amazon Soy Moratorium reduced deforestation. Nature Food1(12), 801–810. https://doi.org/10.1038/s43016-020-00194-5

Hoekstra, J. M., Boucher, T. M., Ricketts, T. H., & Roberts, C. (2005). Confronting a biome crisis: Global disparities of habitat loss and protection. Ecology Letters8(1), 23–29. https://doi.org/10.1111/j.1461-0248.2004.00686.x

Huang, J., Yu, H., Guan, X., Wang, G., & Guo, R. (2016). Accelerated dryland expansion under climate change. Nature Climate Change6(2), 166–171. https://doi.org/10.1038/nclimate2837

Huang, X., Ibrahim, M. M., Luo, Y., Jiang, L., Chen, J., & Hou, E. (2024). Land use change alters soil organic carbon: Constrained global patterns and predictors. Earth’s Future12(5), Article e2023EF004254. https://doi.org/10.1029/2023EF004254

IPCC Task Force on National Greenhouse Gas Inventories. (2019). Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories (Calvo Buendia, E., Tanabe, K., Kranjc, A., Baasansuren, J., Fukuda, M., Ngarize S., Osako, A., Pyrozhenko, Y., Shermanau, P. and Federici, S., Eds.). Intergovernmental Panel on Climate Change. Link to source: https://www.ipcc-nggip.iges.or.jp/public/2019rf/pdf/0_Overview/19R_V0_00_Cover_Foreword_Preface_Dedication.pdf 

Isbell, F., Craven, D., Connolly, J., Loreau, M., Schmid, B., Beierkuhnlein, C., Bezemer, T. M., Bonin, C., Bruelheide, H., de Luca, E., Ebeling, A., Griffin, J. N., Guo, Q., Hautier, Y., Hector, A., Jentsch, A., Kreyling, J., Lanta, V., Manning, P., … Eisenhauer, N. (2015). Biodiversity increases the resistance of ecosystem productivity to climate extremes. Nature526(7574), 574–577. https://doi.org/10.1038/nature15374

Jackson, R. B., Banner, J. L., Jobbágy, E. G., Pockman, W. T., & Wall, D. H. (2002). Ecosystem carbon loss with woody plant invasion of grasslands. Nature418(6898), 623–626. https://doi.org/10.1038/nature00910

Jones, K. R., Venter, O., Fuller, R. A., Allan, J. R., Maxwell, S. L., Negret, P. J., & Watson, J. E. M. (2018). One-third of global protected land is under intense human pressure. Science360(6390), 788–791. https://doi.org/10.1126/science.aap9565

Kachler, J., Benra, F., Bolliger, R., Isaac, R., Bonn, A., & Felipe-Lucia, M. R. (2023). Can we have it all? The role of grassland conservation in supporting forage production and plant diversity. Landscape Ecology38(12), 4451–4465. https://doi.org/10.1007/s10980-023-01729-4

Kemp, D. R., Guodong, H., Xiangyang, H., Michalk, D. L., Fujiang, H., Jianping, W., & Yingjun, Z. (2013). Innovative grassland management systems for environmental and livelihood benefits. Proceedings of the National Academy of Sciences110(21), 8369–8374. https://doi.org/10.1073/pnas.1208063110

Kim, J. H., Jobbágy, E. G., & Jackson, R. B. (2016). Trade-offs in water and carbon ecosystem services with land-use changes in grasslands. Ecological Applications26(6), 1633–1644. https://doi.org/10.1890/15-0863.1

Knapp, A. K., Chen, A., Griffin-Nolan, R. J., Baur, L. E., Carroll, C. J. W., Gray, J. E., Hoffman, A. M., Li, X., Post, A. K., Slette, I. J., Collins, S. L., Luo, Y., & Smith, M. D. (2020). Resolving the Dust Bowl paradox of grassland responses to extreme drought. Proceedings of the National Academy of Sciences117(36), 22249–22255. https://doi.org/10.1073/pnas.1922030117

Lambin, E. F., Gibbs, H. K., Heilmayr, R., Carlson, K. M., Fleck, L. C., Garrett, R. D., le Polain de Waroux, Y., McDermott, C. L., McLaughlin, D., Newton, P., Nolte, C., Pacheco, P., Rausch, L. L., Streck, C., Thorlakson, T., & Walker, N. F. (2018). The role of supply-chain initiatives in reducing deforestation. Nature Climate Change8(2), 109–116. https://doi.org/10.1038/s41558-017-0061-1

Lefcheck, J. S., Byrnes, J. E. K., Isbell, F., Gamfeldt, L., Griffin, J. N., Eisenhauer, N., Hensel, M. J. S., Hector, A., Cardinale, B. J., & Duffy, J. E. (2015). Biodiversity enhances ecosystem multifunctionality across trophic levels and habitats. Nature Communications6(1), Article 6936. https://doi.org/10.1038/ncomms7936

Levy, S. A., Cammelli, F., Munger, J., Gibbs, H. K., & Garrett, R. D. (2023). Deforestation in the Brazilian Amazon could be halved by scaling up the implementation of zero-deforestation cattle commitments. Global Environmental Change80, Article 102671. https://doi.org/10.1016/j.gloenvcha.2023.102671

Li, G., Fang, C., Watson, J. E. M., Sun, S., Qi, W., Wang, Z., & Liu, J. (2024). Mixed effectiveness of global protected areas in resisting habitat loss. Nature Communications15(1), Article 8389. https://doi.org/10.1038/s41467-024-52693-9

Li, J., Huang, L., Cao, W., Wang, J., Fan, J., Xu, X., & Tian, H. (2023). Benefits, potential and risks of China’s grassland ecosystem conservation and restoration. Science of The Total Environment905, Article 167413. https://doi.org/10.1016/j.scitotenv.2023.167413

Liechti, K., & Biber, J.-P. (2016). Pastoralism in Europe: Characteristics and challenges of highland-lowland transhumance. Revue Scientifique Et Technique (International Office of Epizootics)35(2), 561–575. https://doi.org/10.20506/rst.35.2.2541

Macdonald, K., Diprose, R., Grabs, J., Schleifer, P., Alger, J., Bahruddin, Brandao, J., Cashore, B., Chandra, A., Cisneros, P., Delgado, D., Garrett, R., & Hopkinson, W. (2024). Jurisdictional approaches to sustainable agro-commodity governance: The state of knowledge and future research directions. Earth System Governance22, Article 100227. https://doi.org/10.1016/j.esg.2024.100227

Marin, F. R., Zanon, A. J., Monzon, J. P., Andrade, J. F., Silva, E. H. F. M., Richter, G. L., Antolin, L. A. S., Ribeiro, B. S. M. R., Ribas, G. G., Battisti, R., Heinemann, A. B., & Grassini, P. (2022). Protecting the Amazon forest and reducing global warming via agricultural intensification. Nature Sustainability5, 1018–1026. https://doi.org/10.1038/s41893-022-00968-8

McNicol, I. M., Keane, A., Burgess, N. D., Bowers, S. J., Mitchard, E. T. A., & Ryan, C. M. (2023). Protected areas reduce deforestation and degradation and enhance woody growth across African woodlands. Communications Earth & Environment4(1), Article 392. https://doi.org/10.1038/s43247-023-01053-4

Meng, Z., Dong, J., Ellis, E. C., Metternicht, G., Qin, Y., Song, X.-P., Löfqvist, S., Garrett, R. D., Jia, X., & Xiao, X. (2023). Post-2020 biodiversity framework challenged by cropland expansion in protected areas. Nature Sustainability6(7), 758–768. https://doi.org/10.1038/s41893-023-01093-w

Michalk, D. L., Kemp, D. R., Badgery, W. B., Wu, J., Zhang, Y., & Thomassin, P. J. (2019). Sustainability and future food security—A global perspective for livestock production. Land Degradation & Development30(5), 561–573. https://doi.org/10.1002/ldr.3217

Nabuurs, G.-J., Mrabet, R., Hatab, A. A., Bustamante, M., Clark, H., Havlík, P., House, J. I., Mbow, C., Ninan, K. N., Popp, A., Roe, S., Sohngen, B., & Towprayoon, S. (2022). Agriculture, forestry and other land uses (AFOLU). In P. R. Shukla, J. Skea, R. Slade, A. Al Khourdajie, R. van Diemen, D. McCollum, M. Pathak, S. Some, P. Vyas, R. Fradera, M. Belkacemi, A. Hasija, G. Lisboa, S. Luz, & J. Malley (Eds.), Climate change 2022: Mitigation of climate change. Contribution of working group III to the sixth assessment report of the intergovernmental panel on climate change (pp. 747–860). Cambridge University Press. Link to source: https://doi.org/10.1017/9781009157926.009

Nugent, D. T., Baker-Gabb, D. J., Green, P., Ostendorf, B., Dawlings, F., Clarke, R. H., & Morgan, J. W. (2022). Multi-scale habitat selection by a cryptic, critically endangered grassland bird—The Plains-wanderer (Pedionomus torquatus): Implications for habitat management and conservation. Austral Ecology47(3), 698–712. https://doi.org/10.1111/aec.13157

Olson, D. M., Dinerstein, E., Wikramanayake, E. D., Burgess, N. D., Powell, G. V. N., Underwood, E. C., D’amico, J. A., Itoua, I., Strand, H. E., Morrison, J. C., Loucks, C. J., Allnutt, T. F., Ricketts, T. H., Kura, Y., Lamoreux, J. F., Wettengel, W. W., Hedao, P., & Kassem, K. R. (2001). Terrestrial ecoregions of the world: A new map of life on Earth: A new global map of terrestrial ecoregions provides an innovative tool for conserving biodiversity. BioScience51(11), 933–938. https://doi.org/10.1641/0006-3568(2001)051[0933:TEOTWA]2.0.CO;2

Parente, L., Sloat, L., Mesquita, V., Consoli, D., Stanimirova, R., Hengl, T., Bonannella, C., Teles, N., Wheeler, I., Hunter, M., Ehrmann, S., Ferreira, L., Mattos, A. P., Oliveira, B., Meyer, C., Şahin, M., Witjes, M., Fritz, S., Malek, Z., & Stolle, F. (2024a). Annual 30-m maps of global grassland class and extent (2000–2022) based on spatiotemporal Machine Learning. Scientific Data11(1), Article 1303. https://doi.org/10.1038/s41597-024-04139-6

Parente, L., Sloat, L., Mesquita, V., Consoli, D., Stanimirova, R., Hengl, T., Bonannella, C., Teles, N., Wheeler, I., Hunter, M., Ehrmann, S., Ferreira, L., Mattos, A. P., Oliveira, B., Meyer, C., Şahin, M., Witjes, M., Fritz, S., Malek, Ž., & Stolle, F. (2024b). Global Pasture Watch—Annual grassland class and extent maps at 30-m spatial resolution (2000—2022) (Version v1) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.13890417

Pelser, A., Redelinghuys, N., & Kernan, A.-L. (2015). Protected Areas and ecosystem services—Integrating grassland conservation with human well-being in South Africa. In Biodiversity in Ecosystems—Linking Structure and Function. IntechOpen. https://doi.org/10.5772/59015

Petermann, J. S., & Buzhdygan, O. Y. (2021). Grassland biodiversity. Current Biology31(19), R1195–R1201. https://doi.org/10.1016/j.cub.2021.06.060

Poeplau, C. (2021). Grassland soil organic carbon stocks along management intensity and warming gradients. Grass and Forage Science76(2), 186–195. https://doi.org/10.1111/gfs.12537

Poggio, L., de Sousa, L. M., Batjes, N. H., Heuvelink, G. B. M., Kempen, B., Ribeiro, E., & Rossiter, D. (2021). SoilGrids 2.0: Producing soil information for the globe with quantified spatial uncertainty. SOIL7(1), 217–240. https://doi.org/10.5194/soil-7-217-2021

Ratajczak, Z., Nippert, J. B., & Collins, S. L. (2012). Woody encroachment decreases diversity across North American grasslands and savannas. Ecology93(4), 697–703. https://doi.org/10.1890/11-1199.1

Resare Sahlin, K., Gordon, L. J., Lindborg, R., Piipponen, J., Van Rysselberge, P., Rouet-Leduc, J., & Röös, E. (2024). An exploration of biodiversity limits to grazing ruminant milk and meat production. Nature Sustainability7(9), 1160–1170. https://doi.org/10.1038/s41893-024-01398-4

Saura, S., Bertzky, B., Bastin, L., Battistella, L., Mandrici, A., & Dubois, G. (2019). Global trends in protected area connectivity from 2010 to 2018. Biological Conservation238, Article 108183. https://doi.org/10.1016/j.biocon.2019.07.028

Sloat, L., Balehegn, M., & Johnson, P. (2025, May 2). Grasslands Are Some of Earth’s Most Underrated Ecosystems. World Resources Institute. https://www.wri.org/insights/grassland-benefits

Smith, M. D., Wilkins, K. D., Holdrege, M. C., Wilfahrt, P., Collins, S. L., Knapp, A. K., Sala, O. E., Dukes, J. S., Phillips, R. P., Yahdjian, L., Gherardi, L. A., Ohlert, T., Beier, C., Fraser, L. H., Jentsch, A., Loik, M. E., Maestre, F. T., Power, S. A., Yu, Q., … Zuo, X. (2024). Extreme drought impacts have been underestimated in grasslands and shrublands globally. Proceedings of the National Academy of Sciences121(4), Article e2309881120. https://doi.org/10.1073/pnas.2309881120

Spawn, S. A., Sullivan, C. C., Lark, T. J., & Gibbs, H. K. (2020). Harmonized global maps of above and belowground biomass carbon density in the year 2010. Scientific Data7(1), Article 112. https://doi.org/10.1038/s41597-020-0444-4

Stanley, P. L., Wilson, C., Patterson, E., Machmuller, M. B., & Cotrufo, M. F. (2024). Ruminating on soil carbon: Applying current understanding to inform grazing management. Global Change Biology30(3), Article e17223. https://doi.org/10.1111/gcb.17223

Su, X., Han, W., Liu, G., Zhang, Y., & Lu, H. (2019). Substantial gaps between the protection of biodiversity hotspots in alpine grasslands and the effectiveness of protected areas on the Qinghai-Tibetan Plateau, China. Agriculture, Ecosystems & Environment278, 15–23. https://doi.org/10.1016/j.agee.2019.03.013

Suttie, J. M., Reynolds, S. G., & Batello, C. (Eds.). (2005). Grasslands of the world (Vol. 34). Food and Agriculture Organization of the United Nations. Link to source: https://www.fao.org/4/y8344e/y8344e00.htm 

Sze, J. S., Carrasco, L. R., Childs, D., & Edwards, D. P. (2021). Reduced deforestation and degradation in Indigenous Lands pan-tropically. Nature Sustainability5(2), 123–130. https://doi.org/10.1038/s41893-021-00815-2

United Nations Environment Programme World Conservation Monitoring Centre, & International Union for Conservation of Nature. (2024). Protected planet: The world database on protected areas (WDPA) and world database on other effective area-based conservation measures (WD-OECM) [Data set]. Retrieved November 2024, from https://www.protectedplanet.net

Vijay, V., Fisher, J. R. B., & Armsworth, P. R. (2022). Co-benefits for terrestrial biodiversity and ecosystem services available from contrasting land protection policies in the contiguous United States. Conservation Letters15(5), Article e12907. https://doi.org/10.1111/conl.12907

Villoria, N., Garrett, R., Gollnow, F., & Carlson, K. (2022). Leakage does not fully offset soy supply-chain efforts to reduce deforestation in Brazil. Nature Communications13(1), Article 5476. https://doi.org/10.1038/s41467-022-33213-z

Visconti, P., Butchart, S. H. M., Brooks, T. M., Langhammer, P. F., Marnewick, D., Vergara, S., Yanosky, A., & Watson, J. E. M. (2019). Protected area targets post-2020. Science364(6437), 239–241. https://doi.org/10.1126/science.aav6886

Wade, C. M., Austin, K. G., Cajka, J., Lapidus, D., Everett, K. H., Galperin, D., Maynard, R., & Sobel, A. (2020). What is threatening forests in Protected Areas? A global assessment of deforestation in Protected Areas, 2001–2018. Forests11(5), Article 539. https://doi.org/10.3390/f11050539

Waldron, A., Adams, V., Allan, J., Arnell, A., Asner, G., Atkinson, S., Baccini, A., Baillie, J. E. M., Balmford, A., Beau, J. A., Brander, L., Brondizio, E., Bruner, A., Burgess, N., Burkart, K., Butchart, S., Button, R., Carrasco, R., Cheung, W., … Zhang, Y. P. (2020). Protecting 30% of the planet for nature: Costs, benefits and economic implications [Working paper]. International Institute for Applied Systems Analysis. Link to source: https://pure.iiasa.ac.at/id/eprint/16560/1/Waldron_Report_FINAL_sml.pdf

Ward, M., Saura, S., Williams, B., Ramírez-Delgado, J. P., Arafeh-Dalmau, N., Allan, J. R., Venter, O., Dubois, G., & Watson, J. E. M. (2020). Just ten percent of the global terrestrial protected area network is structurally connected via intact land. Nature Communications11(1), Article 4563. https://doi.org/10.1038/s41467-020-18457-x

Watson, J. E. M., Dudley, N., Segan, D. B., & Hockings, M. (2014). The performance and potential of protected areas. Nature515(7525), 67–73. https://doi.org/10.1038/nature13947

West, T. A. P., Wunder, S., Sills, E. O., Börner, J., Rifai, S. W., Neidermeier, A. N., Frey, G. P., & Kontoleon, A. (2023). Action needed to make carbon offsets from forest conservation work for climate change mitigation. Science381(6660), 873–877. https://doi.org/10.1126/science.ade3535

Williams, M., Reay, D., & Smith, P. (2023). Avoiding emissions versus creating sinks—Effectiveness and attractiveness to climate finance. Global Change Biology29(8), 2046–2049. https://doi.org/10.1111/gcb.16598

Wolf, C., Levi, T., Ripple, W. J., Zárrate-Charry, D. A., & Betts, M. G. (2021). A forest loss report card for the world’s protected areas. Nature Ecology & Evolution5(4), 520–529. https://doi.org/10.1038/s41559-021-01389-0

Yao, J., Liu, H., Huang, J., Gao, Z., Wang, G., Li, D., Yu, H., & Chen, X. (2020). Accelerated dryland expansion regulates future variability in dryland gross primary production. Nature Communications11(1), Article 1665. https://doi.org/10.1038/s41467-020-15515-2

Yu, Q., Xu, C., Wu, H., Ke, Y., Zuo, X., Luo, W., Ren, H., Gu, Q., Wang, H., Ma, W., Knapp, A. K., Collins, S. L., Rudgers, J. A., Luo, Y., Hautier, Y., Wang, C., Wang, Z., Jiang, Y., Han, G., … Han, X. (2025). Contrasting drought sensitivity of Eurasian and North American grasslands. Nature639(8053), 114–118. https://doi.org/10.1038/s41586-024-08478-7

Zhu, K., Chiariello, N. R., Tobeck, T., Fukami, T., & Field, C. B. (2016). Nonlinear, interacting responses to climate limit grassland production under global change. Proceedings of the National Academy of Sciences113(38), 10589–10594. https://doi.org/10.1073/pnas.1606734113

Zhu, K., Song, Y., Lesage, J. C., Luong, J. C., Bartolome, J. W., Chiariello, N. R., Dudney, J., Field, C. B., Hallett, L. M., Hammond, M., Harrison, S. P., Hayes, G. F., Hobbs, R. J., Holl, K. D., Hopkinson, P., Larios, L., Loik, M. E., & Prugh, L. R. (2024). Rapid shifts in grassland communities driven by climate change. Nature Ecology & Evolution8(12), 2252–2264. https://doi.org/10.1038/s41559-024-02552-z

Credits

Lead Fellow

  • Avery Driscoll

Contributors

  • Ruthie Burrows, Ph.D.

  • James Gerber, Ph.D.

  • Daniel Jasper

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • Hannah Henkin

  • Ted Otte

  • Christina Richardson, Ph.D.

  • Christina Swanson, Ph.D.

  • Paul C. West, Ph.D.

Effectiveness

We estimated that protecting 1 ha of grasslands avoids 0.06–0.90 t CO₂‑eq/yr, with emissions reductions tending to be higher in boreal and temperate regions than tropical and subtropical regions (100-yr GWP; Table 1a–d; Appendix).

We estimated effectiveness as the avoided emissions attributable to the reduction in grassland conversion conferred by protection (Equation 1; Appendix), assuming that converted grasslands are used as croplands due to data constraints. Although some grasslands are converted to intensively managed pastures or urban development, we assumed that the total land area converted to infrastructure is relatively small and emissions associated with conversion to planted pastures are comparable to those from conversion to cropland.

We aggregated estimates of avoided grassland conversion attributable to PAs from Li et al. (2024) to the biome level (Grassland lossavoided), then multiplied the result by the total emissions over 30 years from 1 ha of grassland converted to cropland. These emissions include the change in biomass and soil carbon on conversion to cropland (Carbonemissions), 30 years of lost carbon sequestration potential (Carbonuptake), and nitrous oxide emissions associated with soil carbon loss, which is a small component of total emissions (see Appendix for details; Chang et al. 2021; Huang et al., 2024; Intergovernmental Panel on Climate Change 2019; Poggio et al., 2021; Spawn et al., 2020).

left_text_column_width

Equation 1.

\[Effectiveness=(Grassland\text{ }loss_{avoided} \times (Carbon_{emissions} + Carbon_{uptake})

The effectiveness of grassland protection as defined here reflects only a small percentage of the carbon stored in grassland because we accounted for the likelihood that the grassland would be converted without protection. Grassland protection is particularly impactful for areas at high risk of conversion.

left_text_column_width

Table 1a–d. Effectiveness of grassland protection at avoiding emissions and sequestering carbon. Regional differences in values are driven by variation in carbon stocks, baseline rates of grassland conversion, and the effectiveness of PAs at reducing conversion.

Unit: t CO₂‑eq (100-yr basis)/ha/yr

Estimate 0.90

Unit: t CO₂‑eq (100-yr basis)/ha/yr

Estimate 0.54

Unit: t CO₂‑eq (100-yr basis)/ha/yr

Estimate 0.13

Unit: t CO₂‑eq (100-yr basis)/ha/yr

Estimate 0.06
Left Text Column Width
Cost

The costs of grassland protection include up-front costs of land acquisition and ongoing costs of management and enforcement. The market price of land reflects the opportunity cost of not using the land for other purposes, such as agriculture or urban development. Data related to the costs of grassland protection are very limited. 

We estimated that grassland protection provides a net cost savings of approximately US$0.53/ha/yr, or US$1.58/t CO₂‑eq avoided (Table 2). This estimate reflects global averages rather than regionally specific values, and some data are not specific to grasslands. Costs and revenues are highly variable across regions, depending on the costs of land and enforcement and the potential for tourism. 

Dienerstein et al. (2024) estimated the initial cost of establishing a PA for 60 high-biodiversity ecoregions. Amongst the 20 regions that contain grasslands, the median acquisition cost was US$897/ha, which we amortized over 30 years. Costs of PA maintenance were estimated at US$9–17/ha/yr (Bruner et al., 2004; Waldron et al., 2020), though these estimates were not specific to grasslands. Additionally, these estimates reflect the costs of effective enforcement and management, but many existing PAs lack adequate funds for effective enforcement (Adams et al., 2019; Barnes et al., 2018; Burner et al., 2004). 

Protecting grasslands can generate revenue through increased tourism. Waldron et al. (2020) estimated that, across all ecosystems, tourism revenues directly attributable to PA establishment were US$43 ha/yr, not including downstream revenues from industries that benefit from increased tourism. Inclusion of a tourism multiplier would substantially increase the estimated economic benefits of grassland protection.

left_text_column_width

Table 2. Cost per unit of climate impact for grassland protection. Negative value indicates cost savings.

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

median -1.58
Left Text Column Width
Learning Curve

A learning curve is defined here as falling costs with increased adoption. The costs of grassland protection do not fall with increasing adoption, so there is no learning curve for this solution.

left_text_column_width
Speed of Action

The term speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is separate from the speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Protect Grasslands is an EMERGENCY BRAKE climate solution. It reduces pulses of emissions from the conversion of grasslands, offering the potential to deliver a more rapid impact than gradual and delayed solutions. Because emergency brake solutions can deliver their climate benefits quickly, they can help accelerate our efforts to address dangerous levels of climate change. For this reason, they are a high priority.

left_text_column_width
Caveats

Permanence, or the durability of stored carbon, is a caveat for emissions avoidance through grassland protection that is not addressed in this analysis. Protected grasslands could be converted to agricultural uses or other development if legal protections are reversed or inadequately enforced, resulting in the loss of stored carbon. Many PAs allow for some human uses, and PA management that is not tailored to grazing needs, fire dependency, or woody plant encroachment can reduce carbon stocks within PAs (Barger et al., 2011; Chang et al., 2021; Conant et al, 2017; Jackson et al., 2002; Kemp et al., 2013; Popleau et al., 2011). Climate change is also causing widespread degradation of grasslands, including reductions in vegetation productivity that may reduce carbon storage over the long term even in the absence of additional disturbance (Chang et al., 2021; Gang et al., 2014; Li et al., 2023; Zhu et al., 2016). Climate change and aridification may also cause expansion of grassland extent (Berg & McColl, 2021; Feng & Fu, 2014; Huang et al., 2016), with mixed but overall negative impacts on terrestrial carbon uptake (Yao et al., 2020).

Additionality, or the degree to which emissions reductions are above and beyond a baseline, is another important caveat for emissions avoidance through ecosystem protection (Ahlering et al., 2016; Williams et al., 2023). In this analysis, additionality was addressed by using baseline rates of grassland conversion in calculating effectiveness. Evaluating additionality is challenging and remains an active area of research.

left_text_column_width
Current Adoption

A total of 555 Mha of grasslands (excluding grasslands on peat soils, grasslands that are also coastal wetlands, and grasslands created through deforestation) are currently located within PAs, and an additional 832 Mha are located on IPLs not classified as PAs (Table 3e). That means that ~48% of grasslands are under some form of protection globally, with 6% in strict PAs, 13% in non-strict PAs, and 29% on IPLs that are not also PAs. As of 2023, tropical regions had the largest extent of protected grasslands (583 Mha), followed by boreal regions (339 Mha), and subtropical regions (293 Mha). In temperate regions, only 24% of grasslands (172 Mha) were under any form of protection (Table 3a–d).

left_text_column_width

Table 3a–e. Grassland under protection by biome (circa 2023). Estimates are provided for three different forms of protection: “strict” protection, including IUCN classes I and II; “non-strict” protection, including all other IUCN categories; and IPLs outside of PAs. Regional values may not sum to global totals due to rounding.

Unit: ha protected

Strict PAs 52,564,000
Non-strict PAs 82,447,000
IPLs 203,579,000

Unit: ha protected

Strict PAs 30,242,000
Non-strict PAs 51,033,000
IPLs 90,973,000

Unit: ha protected

Strict PAs 31,949,000
Non-strict PAs 83,745,000
IPLs 177,301,000

Unit: ha protected

Strict PAs 56,233,000
Non-strict PAs 166,356,000
IPLs 359,997,000

Unit: ha protected

Strict PAs 170,988,000
Non-strict PAs 383,581,000
IPLs 831,850,000
Left Text Column Width
Adoption Trend

We calculated the annual rate of new grassland protection based on the year of PA establishment for areas established in 2000–2020. The median annual increase in grassland protection was 8.1 Mha (mean 11.4 Mha; Table 4e). This represents a roughly 1.5%/yr increase in grasslands within PAs, or protection of an additional 0.3%/yr of total global grasslands. 

Grassland protection has proceeded more quickly in tropical regions (median increase of 4.0 Mha/yr) than in other climate zones (median increases of 1.2–1.6 Mha/yr) (Table 4a–d). Although the global rate of grassland protection fluctuates from year to year, the median rate has remained stable in recent decades at 10.2 Mha/yr from 2000–2009 and 10.4 Mha/yr from 2010–2020. 

left_text_column_width

Table 4a–e. Adoption trend for grassland protection in PAs of any IUCN class (2000–2020). The 25th and 75th percentiles reflect only interannual variance (ha grassland protected/yr). IPLs are not included in this analysis due to a lack of data.

Unit: ha grassland protected/yr

25th percentile 659,000
median (50th percentile) 1,338,000
mean 2,152,000
75th percentile 3,007,000

Unit: ha grassland protected/yr

25th percentile 692,000
median (50th percentile) 1,178,000
mean 1,728,000
75th percentile 1,715,000

Unit: ha grassland protected/yr

25th percentile 940,000
median (50th percentile) 1,580,000
mean 2,791,000
75th percentile 3,226,000

Unit: ha grassland protected/yr

25th percentile 2,628,000
median (50th percentile) 4,044,000
mean 4,711,000
75th percentile 5,774,000

Unit: ha grassland protected/yr

25th percentile 4,919,000
median (50th percentile) 8,140,000
mean 11,382,000
75th percentile 13,722,000
Left Text Column Width
Adoption Ceiling

Including grasslands that are currently protected, we estimated that there are approximately 2,891 Mha of natural grasslands that are not counted in a different solution (Table 5e). This ceiling includes 1,505 Mha that are not currently under any form of protection. This includes 533 Mha of eligible grasslands in boreal regions, 723 Mha in temperate regions, 626 Mha in the subtropics, and 1,008 Mha in the tropics (Table 5a–d). 

To develop these estimates, we relied on the global grassland map from Parente et al. (2024), excluded areas that were included in the Protect ForestsProtect Peatlands, and Protect Coastal Wetlands solutions, and excluded areas that were historically forested according to the Terrestrial Ecoregions of The World dataset (Olson et al., 2001; Appendix). While it is not socially, politically, or economically realistic that all remaining grasslands could be protected, these values represent the technical upper limit to adoption of this solution.

left_text_column_width

Table 5a–e. Adoption ceiling: upper limit for adoption of legal protection of grasslands by biome. Values may not sum to global totals due to rounding. 

Unit: ha protected

Estimate 533,033,000

Unit: ha protected

Estimate 723,429,000

Unit: ha protected

Estimate 626,474,000

Unit: ha protected

Estimate 1,008,375,000

Unit: ha protected

Estimate 2,891,311,000
Left Text Column Width
Achievable Adoption

We assigned a low achievable level of a minimum of 50% of grasslands in each climate zone (Table 6a–e). For boreal and tropical regions, in which 64% and 58%, respectively, of grasslands are already protected, we assume no change in PA (Table 6a, d). For temperate areas, the low achievable target reflects an increase of 189 Mha, or more than a doubling of the current PA extent (Table 6b). In subtropical zones, this target reflects an additional 20 Mha under protection (Table 6c). We assigned a high achievable level of 70% of grasslands in each climate zone, reflecting an additional 637 Mha of protected grasslands globally, or a 46% increase in the current PA extent (Table 6a–e).

left_text_column_width

Table 6a–e. Range of achievable adoption of grassland protection by biome.

Unit: ha protected

Current Adoption 338,590,000
Achievable – Low 338,590,000
Achievable – High 373,123,000
Adoption ceiling 533,033,000

Unit: ha protected

Current Adoption 172,248,000
Achievable – Low 361,715,000
Achievable – High 506,400,000
Adoption ceiling 723,429,000

Unit: ha protected

Current Adoption 292,995,000
Achievable – Low 313,237,000
Achievable – High 438,532,000
Adoption ceiling 626,474,000

Unit: ha protected

Current Adoption 582,586,000
Achievable – Low 582,586,000
Achievable – High 705,863,000
Adoption ceiling 1,008,375,000

Unit: ha protected

Current Adoption 1,386,419,000
Achievable – Low 1,596,128,000
Achievable – High 2,023,918,000
Adoption ceiling 2,891,311,000
Left Text Column Width

We estimated that PAs currently reduce GHG emissions from grassland conversion by 0.468 Gt CO₂‑eq/yr (Table 7a–e). Achievable levels of grassland protection have the potential to reduce emissions 0.572–0.704 Gt CO₂‑eq/yr, with a technical upper bound of 1.006 Gt CO₂‑eq/yr (Table 7a–e). This indicates that further emissions reductions of 0.105–0.237 Gt CO₂‑eq/yr are achievable. For these benefits to be realized, grazing, fire, and woody plant management must be responsive to local grassland needs and compatible with the maintenance of carbon stocks. The solutions Improve Livestock Grazing and Deploy Silvopasture address the climate impacts of some aspects of grassland management.

Few other sources explicitly quantify the climate impacts of grassland protection, but the available data are roughly aligned with our estimates of additional mitigation potential. The Intergovernmental Panel on Climate Change estimated that avoided conversion of grasslands to croplands could reduce emissions by 0.03–0.7 Gt CO₂‑eq/yr (Nabuurs et al., 2022). Griscom et al. (2017) estimated that avoided grassland conversion could save 0.12 Gt CO₂‑eq/yr emissions from soil carbon only (not counting loss of vegetation, sequestration potential, or nitrous oxide), though their analysis did not account for current protection and relied on older estimates of grassland conversion. 

left_text_column_width

Table 7a–e. Climate impact at different levels of adoption.

Unit: GtCO₂‑eq/yr, 100-year basis

Current Adoption 0.305
Achievable – Low 0.305
Achievable – High 0.336
Adoption Ceiling 0.481

Unit: GtCO₂‑eq/yr, 100-year basis

Current Adoption 0.093
Achievable – Low 0.195
Achievable – High 0.273
Adoption Ceiling 0.390

Unit: GtCO₂‑eq/yr, 100-year basis

Current Adoption 0.037
Achievable – Low 0.039
Achievable – High 0.055
Adoption Ceiling 0.078

Unit: GtCO₂‑eq/yr, 100-year basis

Current Adoption 0.033
Achievable – Low 0.033
Achievable – High 0.040
Adoption Ceiling 0.057

Unit: GtCO₂‑eq/yr, 100-year basis

Current Adoption 0.468
Achievable – Low 0.572
Achievable – High 0.704
Adoption Ceiling 1.006
Left Text Column Width
Additional Benefits

Floods

Grassland plants often have deep root systems, leading to high soil carbon stocks (Sloat et al., 2025). These roots can absorb water and reduce discharge into surrounding water bodies during periods of excessive rain (GRaSS, 2024).

Droughts

Different grassland plant species respond differently to drought. Differences in precipitation seasonality due to drought may allow some grass species to dominate over others (Knapp et al., 2020). Evidence suggests that higher species diversity can enhance grassland resilience to drought (Smith et al., 2024; Yu et al., 2025).  Additionally, the deep root systems of grassland plants contribute to the drought resilience of these ecosystems (Sloat et al., 2025). More resilient, biodiverse grasslands are associated with greater ecosystem stability and productivity, and can maintain ecosystem services during periods of extreme weather, such as drought (Isbell et al, 2015; Lefcheck et al., 2015).

Income and Work

Grasslands are an important source of income for surrounding communities through tourism and other ecosystem services (Bengtsson et al., 2019). Protecting grasslands sustains the long-term health of the ecosystem, which is especially important for subsistence livelihoods that depend on intact landscapes for incomes (Pelser, 2015). Sources of income that are directly generated from grasslands include: meat, milk, wool, and leather and thatching materials to make brooms, hats, and baskets (GRaSS, 2024; Pelser, 2015). People living near grasslands often rely on grazing livestock for food and income (GRaSS, 2024, Kemp 2013, Su et al., 2019). Grasslands in China support the livelihoods of about 16 million people, many of whom live in poverty (Kemp et al., 2013). The Qinghai-Tibetan Plateau is especially important for grazing livestock (Su et al., 2019). Evidence has shown that declines in grassland productivity are also linked to declines in income (Kemp et al., 2013).

Food Security

Grasslands can contribute to food security by providing food for livestock and supporting pollinators for nearby agriculture (Sloat et al., 2025). Grassland-based grazing systems are important sources of food for populations in low and middle-income countries, particularly in Oceania, Latin America, the Caribbean, the Middle East, North Africa, and sub-Saharan Africa (Resare Sahlin et al., 2023). Grasslands can support the food security of smallholder farmers and pastoralists in these regions by providing meat and milk (GRaSS, 2024; Michalk, 2018). 

Equality

Grasslands are central to many cultures, and grassland protection can support shared cultural and spiritual values for many populations. They can be sources of identity for people living in or near grassland ecosystems who have strong connections with the land (Bengtsson et al., 2019, GRaSS, 2024). For example, in Mongolia grasslands sustain horses, which are central to the cultural identities and livelihoods of communities, particularly nomadic populations (Kemp et al., 2014). Grasslands can also be an important source of shared identity for pastoralists who move herds to graze based on seasonal cycles during the year (Liechti & Biber, 2016).

Nature Protection

Many grasslands are biodiversity hot spots (Petermann & Buzhdygan, 2021; Su et al., 2019). Numerous plant and animal species are endemic to grasslands, meaning they have limited habitat ranges and can easily become endangered with habitat degradation (Sloat et al., 2025). In Germany, grasslands in PAs were found to have higher plant diversity than in non-PAs (Kachler et al., 2023). Grasslands are important habitats for bird species that rely on them for breeding grounds (GRaSS, 2024; Nugent et al., 2022).

Land Resources

The unique, deep root structures of some grassland plants can improve soil stability and reduce soil erosion (Bengtsson et al., 2019; GRaSS, 2024; Kemp et al., 2013).

Water Resources

Grasslands can regulate water flows and water storage. The root systems can help rainwater reach deep underground, recharging groundwater stores (Bengtsson et al., 2019; GRaSS, 2024).

left_text_column_width
Risks

Relying on grassland protection as an emissions reduction strategy can be undermined if ecosystem conversion that is not allowed inside a PA simply takes place outside of it instead (Aherling et al., 2016; Asamoah et al., 2021). If such leakage leads to conversion of ecosystems that have higher carbon stocks, such as forests, peatlands, or coastal wetlands, total emissions may increase. Combining grassland protection with policies to reduce incentives for ecosystem conversion can help avoid leakage.

left_text_column_width
Interactions with Other Solutions

Reinforcing

PAs often include multiple ecosystems. Grassland protection will likely lead to protection of other ecosystems within the same areas, and the health of nearby ecosystems is improved by the services provided by intact grasslands. 

left_text_column_width

These solutions reduce pressure to convert grasslands to agricultural use, easing the expansion of PAs.

left_text_column_width

Restored grasslands need protection to reduce the risk of future disturbance, and the health of protected grasslands can be improved through the restoration of adjacent degraded grasslands.

left_text_column_width

Grazing by large herbivores is critical for the health of many grasslands, and healthy grasslands are needed to support restoration of large herbivores.

left_text_column_width

Competing

Additional crop deployment can increase demand for agricultural land, reducing the grassland area available for protection. 

left_text_column_width

Grassland protection may reduce land availability for renewable energy infrastructure.

left_text_column_width
Dashboard

Solution Basics

ha of grassland or savanna protected

t CO₂-eq (100-yr)/unit/yr
0.9
units
Current 3.386×10⁸ 03.386×10⁸3.731×10⁸
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.305 0.3050.336
US$ per t CO₂-eq
-2
Emergency Brake

CO₂,  N₂O

Solution Basics

ha of grassland or savanna protected

t CO₂-eq (100-yr)/unit/yr
0.54
units
Current 1.722×10⁸ 03.617×10⁸5.064×10⁸
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.093 0.1950.273
US$ per t CO₂-eq
-2
Emergency Brake

CO₂,  N₂O

Solution Basics

ha of grassland or savanna protected

t CO₂-eq (100-yr)/unit/yr
0.13
units
Current 2.93×10⁸ 03.132×10⁸4.385×10⁸
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.037 0.0390.055
US$ per t CO₂-eq
-2
Emergency Brake

CO₂,  N₂O

Solution Basics

ha of grassland or savanna protected

t CO₂-eq (100-yr)/unit/yr
0.06
units
Current 5.826×10⁸ 05.826×10⁸7.059×10⁸
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.033 0.0330.04
US$ per t CO₂-eq
-2
Emergency Brake

CO₂,  N₂O

Trade-offs

Establishment of PAs may limit local access to grasslands for grazing or other forms of income generation, although effective management plans should account for the grazing needs of the protected grassland. Second, allocation of budgetary resources to PA establishment may divert resources from maintenance and enforcement of existing PAs. Finally, protection of grasslands may reduce land availability for renewable energy infrastructure, such as solar and wind power.

left_text_column_width
Action Word
Protect
Solution Title
Grasslands & Savannas
Classification
Highly Recommended
Lawmakers and Policymakers
  • Set scalable targets (across both biogeographic and administrative levels) for grassland protections, including outcomes-based reporting, indicators for the rate of progress, goals for inclusivity, and measurements for enforcement efficacy; incorporate these targets into national climate plans and multilateral agreements.
  • Ensure public procurement uses products and supply chains that do not disrupt PAs and grasslands; ensure public development projects do not disturb PAs and grasslands.
  • Grant Indigenous communities full property rights and autonomy and support them in monitoring, managing, and enforcing PAs; adhere to principles of free, prior, and informed consent when engaging with Indigenous communities and lands.
  • Manage fire, biodiversity, and grazing in protected grasslands in accordance with ecological needs, learning from and working with Indigenous communities.
  • Ensure PAs don’t displace, violate rights, or reduce access to vital resources for local and Indigenous communities.
  • Expand regulatory, legal, and technical support for privately protected grasslands.
  • When expanding PAs, acquire relevant adjacent properties first, if possible, to increase connectivity and reduce costs; grant restored grasslands protected status.
  • Invest in PA infrastructure, monitoring, management, and enforcement mechanisms.
  • Ban or restrict overgrazing and extractive harvesting while allowing for sustainable use of PAs from Indigenous and local communities; compensate herders for lost grazing lands, if necessary.
  • Ensure PAs are adequately financed and, if applicable, provide financing for low- and middle-income countries and communities for grassland protections.
  • Ensure incentives and/or compensation for reducing livestock or protecting grasslands are evenly distributed with particular attention to low- and middle-income farmers and communities.
  • Use financial incentives such as subsidies, tax breaks, payments for ecosystem services (PES), and debt-for-nature swaps to protect grasslands from development.
  • Remove harmful subsidies for agricultural, grazing, mining, and other resource extraction.
  • Use co-management, community-governed, land-trust, and/or privately protected models to expand PAs, increase connectivity, and engage communities; ensure a participatory approach to designating and managing PAs.
  • Use real-time monitoring, ground-level sensors, and satellite data to enforce protections, ensuring adequate baseline data are gathered if possible.
  • Ensure budgets adequately split financing between expanding PAs and managing PAs; prioritize quality management of existing PAs before expanding new designations except in cases where nonprotected land conversion presents the most serious risks to people, the climate, or biodiversity.
  • Conduct proactive land-use planning to avoid roads and other development projects that may interfere with PAs or incentivize development.
  • Create processes for legal grievances, dispute resolution, and restitution.
  • Create programs that educate the public on PA regulations, the benefits of the regulations, and how to use grassland resources sustainably.
  • Join, support, or create certification and independent audit schemes to monitor effectiveness and identify necessary improvements in management.
Practitioners
  • Set scalable targets (across both biogeographic and administrative levels) for grassland protection, including outcomes-based reporting, indicators for the rate of progress, goals for inclusivity, and measurements for enforcement efficacy; advocate to incorporate these targets into national climate plans and multilateral agreements.
  • Improve monitoring and evaluation standards for grassland ecologies and the impacts from animal agriculture.
  • Ensure incentives and/or compensation for reducing livestock or protecting grasslands are evenly distributed with particular attention to low- and middle-income farmers and communities.
  • Ensure PAs are adequately financed and, if applicable, provide financing for low- and middle-income countries and communities for grassland protections.
  • When expanding PAs, acquire relevant adjacent properties first, if possible, to increase connectivity and reduce costs.
  • Use financial incentives such as subsidies, tax breaks, PES, and debt-for-nature swaps to protect grasslands from development.
  • Empower local communities to manage grasslands and ensure a participatory approach to designating and managing PAs.
  • Use co-management, community-governed, land-trust, and/or privately-protected models to expand PAs, increase connectivity, and engage communities.
  • Ban or restrict overgrazing and extractive harvesting while allowing sustainable use of PAs by Indigenous and local communities; compensate herders for lost grazing lands if necessary.
  • Use real-time monitoring, ground-level sensors, and satellite data to enforce protections, ensuring adequate baseline data are gathered if possible.
  • Ensure budgets adequately split financing between expanding PAs and managing PAs; prioritize quality management of existing PAs before expanding new designations - except in cases where non-protected land conversion presents the most serious risk to people, the climate, or biodiversity.
  • Create education programs that educate the public on PA regulations, the benefits of the regulations, and how to use grassland resources sustainably.
  • Join, support, or create certification and independent audit schemes to monitor effectiveness and identify necessary improvements in management.
Business Leaders
  • Ensure operations, development, and supply chains are not degrading grasslands or interfering with PA management.
  • Integrate grassland protection into net-zero strategies, if relevant.
  • Commit and adhere to minimizing irrecoverable carbon loss through development projects, supply-chain management, and general operations.
  • Help revise existing or create new high-integrity carbon markets, institutions, rules, and norms to cultivate the demand for high-quality carbon credits.
  • Only purchase carbon credits from high-integrity, verifiable carbon markets, and do not use them as replacements for decarbonizing operations or claim them as “offsets.”
  • Consider donating to established grassland protection funds in place of carbon credits.
  • Take advantage of financial incentives such as subsidies, tax breaks, and PES to grasslands from development.
  • Amplify the voices of local communities and civil society to promote robust media coverage.
  • Invest in and support Indigenous and local communities' capacity for management, legal protection, and public relations.
  • Leverage political influence to advocate for stronger grassland protection policies at national and international levels.
  • Conduct proactive land use planning to avoid roads and other development projects that may interfere with PAs.
  • Join, support, or create certification and independent audit schemes to monitor effectiveness and identify necessary improvements in management.

Further information:

Nonprofit Leaders
  • Advocate for enhanced enforcement of existing PAs and IPLs, expansion of new PAs and IPLs, and for more public investments.
  • Advocate for scalable targets (across both biogeographic and administrative levels) for grassland protections, including outcomes-based reporting, indicators for the rate of progress, goals for inclusivity, and measurements for enforcement efficacy; advocate for these goals to be incorporated into national climate plans and multilateral agreements.
  • Help manage and monitor protected grasslands using real-time monitoring, ground-based sensors, and satellite data.
  • Provide financial support for monitoring and enforcement of PAs and IPLs.
  • Help conduct proactive land-use planning to avoid infrastructure or development projects that may interfere with protected grasslands or incentivize destruction.
  • Advocate for creating legal grievance processes, dispute resolution mechanisms, and restitution procedures for violations or disagreements over PAs or IPLs.
  • Help revise existing or create new high-integrity carbon markets, institutions, rules, and norms to cultivate the demand for high-quality carbon credits.
  • Amplify the voices of local communities and civil society to promote robust media coverage.
  • Invest in and support the capacity of Indigenous and local communities for management, legal protection, and public relations.
  • Use or advocate for financial incentives such as subsidies, tax breaks, and PES to protect grasslands from development.
  • Improve monitoring and evaluation standards for grassland ecologies and the impacts from animal agriculture.
  • Help classify and map grasslands, carbon stocks, and biodiversity data and create local, national, and international standards for classification.
  • Work with insurance companies to reduce insurance premiums for properties that protect or maintain grasslands.
  • Create and manage a global database of protected grasslands, grassland loss, restoration, and management initiatives.
  • Join, support, or create certification and independent audit schemes to monitor effectiveness and identify necessary improvements in management.
  • Create programs that educate the public on PA regulations, the benefits of the regulations, and how to use grassland resources sustainably.

Further information:

Investors
  • Ensure investment portfolios do not degrade grasslands or interfere with PAs or IPLs, using data, information, and the latest technology to inform investments.
  • Consider any project that releases irrecoverable carbon loss through the destruction of ecosystems like grasslands to be high risk, avoid investments in these projects as much as possible, and divest from any companies violating this principle.
  • Invest in grassland protection, monitoring, management, and enforcement mechanisms.
  • Use financial mechanisms such as credible biodiversity offsets, payments for ecosystem services, voluntary high-integrity carbon markets, and debt-for-nature swaps to fund grassland protection.
  • Invest in and support the capacity of Indigenous and local communities for management, legal protection, and public relations.
  • Share with other investors and nongovernmental organizations data, information, and investment frameworks that successfully avoid investments that drive grassland destruction.
  • Provide favorable loans to Indigenous communities and entrepreneurs and businesses protecting grasslands.
  • Join, support, or create certification and independent audit schemes to monitor effectiveness and identify necessary improvements in management.

Further information:

Philanthropists and International Aid Agencies
  • Advocate for enhanced enforcement of existing PAs and IPLs, expansion of new PAs and IPLs, and more public investments.
  • Advocate for scalable targets (across both biogeographic and administrative levels) for grassland protections, including outcomes-based reporting, indicators for the rate of progress, goals for inclusivity, and measurements for enforcement efficacy; advocate for these goals to be incorporated into national climate plans and multilateral agreements.
  • Use or advocate for financial incentives such as subsidies, tax breaks, and PES to protect grasslands from development.
  • Help manage and monitor protected grassland, using real-time monitoring and satellite data.
  • Provide technical assistance to low- and middle-income countries and communities for grasslands protection.
  • Provide financial assistance to low- and middle-income countries and communities for grasslands protection.
  • Provide financial support to organizations and institutions developing and deploying monitoring technology and conducting grassland research.
  • Help conduct proactive land-use planning to avoid infrastructure or development projects that may interfere with protected grasslands or incentivize destruction.
  • Help revise existing or create new high-integrity carbon markets, institutions, rules, and norms to cultivate the demand for high-quality carbon credits.
  • Amplify the voices of local communities and civil society to promote robust media coverage.
  • Invest in and support Indigenous and local communities' capacity for management, legal protection, and public relations.
  • Advocate for creating legal grievance processes, dispute resolution mechanisms, and restitution procedures for violations or disagreements over PAs or IPLs.
  • Help classify and map grasslands, carbon stocks, and biodiversity data and create local, national, and international standards for classification.
  • Work with insurance companies to reduce insurance premiums for properties that protect or maintain grasslands.
  • Create and manage a global database of protected grasslands, grassland loss, restoration, and management initiatives.
  • Join, support, or create certification and independent audit schemes to monitor effectiveness and identify necessary improvements in management.
  • Create education programs that educate the public on PA regulations, the benefits of the regulations, and how to use grassland resources sustainably.

Further information:

Thought Leaders
  • Help change the narrative around grasslands by highlighting their value and benefits such as supporting human life, biodiversity, ecosystem resilience, and climate regulation.
  • Advocate for enhanced enforcement of existing PAs and IPLs, expansion of new PAs and IPLs, and public investments.
  • Advocate for scalable targets (across both biogeographic and administrative levels) for grassland protections, including outcomes-based reporting, indicators for the rate of progress, goals for inclusivity, and measurements for enforcement efficacy; advocate for these to be incorporated into national climate plans and multilateral agreements.
  • Advocate for or use financial incentives such as subsidies, tax breaks, PES, and debt-for-nature swaps to protect grasslands from development.
  • Help manage and monitor protected grasslands using real-time monitoring and satellite data.
  • Help conduct proactive land-use planning to avoid infrastructure or development projects that may interfere with protected grasslands or incentivize conversion.
  • Advocate for creating legal grievance processes, dispute resolution mechanisms, and restitution procedures for violations or disagreements over PAs or IPLs.
  • Help improve monitoring and evaluation standards for grassland ecologies and impacts from animal agriculture.
  • Help revise existing or create new high-integrity carbon and biodiversity markets, institutions, rules, and norms to cultivate the demand for high-quality carbon credits.
  • Amplify the voices of local communities and civil society to promote robust media coverage.
  • Support Indigenous and local communities' capacity for legal protection, management, and public relations.
  • Help classify and map grasslands, carbon stocks, and biodiversity data and create local, national, and international standards for classification.
  • Create and manage a global database of protected grasslands, grassland loss, restoration, and management initiatives.
  • Join, support, or create certification and independent audit schemes to monitor effectiveness and identify necessary improvements in management.
  • Create programs that educate the public on PA regulations, the benefits of the regulations, and how to use grassland resources sustainably.

Further information:

Technologists and Researchers
  • Develop standardized indicators of grassland degradation.
  • Research the ecological interactions of grasslands with other ecosystems; share data widely and include recommendations for coordinated action.
  • Assess and publish costs of PA designation, management, and evaluation.
  • Conduct comparative analysis on different types of governance models for PAs to determine impacts on climate, biodiversity, and human well-being.
  • Examine the relationship between geography and governance structures of private PAs, looking for spatial patterns and roles of various stakeholders such NGOs, businesses, and private landowners.
  • Study behavioral change mechanisms that can increase effectiveness and enforcement of PAs.
  • Improve monitoring methods using field measurements, models, satellite imagery, and GIS tools.
  • Create or improve on existing software tools that allow for dynamic planning and management of PAs by monitoring impacts on local communities, the climate, and biodiversity.
  • Create local research sites to support PAs and provide technical assistance.
  • Create tools for local communities to monitor grasslands, such as mobile apps, e-learning platforms, and mapping tools.
  • Develop supply chain tracking software for investors and businesses seeking to create sustainable portfolios and products.

Further information:

Communities, Households, and Individuals
  • Avoid developing intact grasslands and adhere to sustainable use guidelines of PAs.
  • Participate or volunteer in local grassland protection efforts; use or advocate for co-management, community-governed, land-trust, and/or privately protected models to expand PAs, increase connectivity, and allow for continued community engagement.
  • Help manage and monitor protected grasslands using real-time monitoring and satellite data.
  • Establish coordinating bodies for farmers, herders, developers, landowners, policymakers, and other stakeholders to holistically manage PAs.
  • Advocate for enhanced enforcement of existing PAs and IPLs, expansion of new PAs and IPLs, and public investments.
  • Help conduct proactive land-use planning to avoid infrastructure or development projects that may interfere with protected grasslands or incentivize destruction.
  • Advocate for creating legal grievance processes, dispute resolution mechanisms, and restitution procedures for violations or disagreements over PAs or IPLs.
  • Help revise existing or create new high-integrity carbon and biodiversity markets, institutions, rules, and norms to cultivate the demand for high-quality carbon credits.
  • Support Indigenous communities' capacity for management, legal protection and public relations.
  • Use or advocate for financial incentives such as subsidies, tax breaks, and PES to protect grasslands from development.
  • Help classify and map grasslands and create local, national, and international standards for classification.
  • Ensure PAs don’t displace, violate rights, or reduce access to vital resources for local and Indigenous communities.
  • Work with insurance companies to reduce insurance premiums for properties that protect or maintain grasslands.
  • Plant native species to help improve the local ecological balance and stabilize the soil, especially on property adjacent to PAs.
  • Use nontoxic cleaning and gardening supplies, purchase unbleached paper products, and recycle to help keep pollution and debris out of grasslands.
  • Join, support, or create certification and independent audit schemes to monitor effectiveness and identify necessary improvements in management.
  • Create programs that educate the public on PA regulations, the benefits of the regulations, and how to use grassland resources sustainably.

Further information:

Evidence Base

Consensus of effectiveness in reducing emissions and maintaining carbon removal: High

There is high scientific consensus that grassland protection reduces emissions by reducing conversion of grasslands to croplands. Grasslands have been extensively converted globally because of their utility for agricultural use, and many extant grasslands are at high risk of conversion (Carbutt et al., 2017; Gang et al., 2014). Li et al. (2024) found that PAs prevent conversion of approximately 0.35% of global grasslands per year. Although grasslands remain understudied relative to some other ecosystems, there is robust evidence that PAs and IPLs reduce forest conversion, with estimates in different regions ranging from 17–75% reductions in forest loss relative to unprotected areas (Baragwanth & Bayi, 2020; Graham et al., 2021; McNichol et al., 2023; Sze et al., 2022; Wolf et al., 2022). Additional research specific to grasslands on the effectiveness of PAs and IPLs at preventing land use change would be valuable. 

Conversion of grasslands to croplands produces emissions through the loss of soil carbon and biomass (IPCC, 2019). A recent meta-analysis based on 5,980 soil carbon measurements found that grassland conversion to croplands reduces soil carbon stocks by a global average of 23%, or almost 30 t CO₂ /ha (Huang et al., 2024), before accounting for nitrous oxide emissions (IPCC, 2019), loss of biomass carbon stocks (Spawn et al., 2020), and loss of sequestration potential (Chang et al., 2021).

Regional studies also find that grassland protection provides emissions savings. For instance, a study of grasslands in Argentina and the United States found that conversion to croplands reduced total carbon stocks, including soil and biomass, by 117 t CO₂‑eq /ha (Kim et al., 2016). Ahlering et al. (2016) conclude that protecting just 210,000 ha of unprotected grasslands in the U.S. Northern Great Plains would avoid 11.7 Mt CO₂‑eq over 20 years, with emissions savings of 51.6 t CO₂‑eq /ha protected, or 35.6 t CO₂‑eq /ha after accounting for leakage and uncertainty. 

The quantitative results presented in this assessment synthesize findings from 13 global datasets supplemented by three meta-analyses with global scopes. We recognize that geographic bias in the information underlying global data products creates bias and hope this work inspires research and data sharing on this topic in underrepresented regions.

left_text_column_width
Appendix

This analysis quantifies the emissions avoidable through legal protection of grasslands via establishment of PAs or land tenure for Indigenous peoples. We leveraged a global grassland distribution map alongside other ecosystem distribution maps, shapefiles of PAs and IPLs, available data on rates of avoided ecosystem loss attributable to PA establishment, maps of grassland carbon stocks in above- and below-ground biomass, and biome-level estimates of soil carbon loss for grasslands converted to croplands. This appendix describes the source data products and how they were integrated. 

Grassland Extent

We relied on the 30-m resolution global map of grassland extent developed by Parente et al. (2024), which classifies both “natural and semi-natural grasslands” and “managed grasslands.” This solution considers only the “natural and semi-natural grasslands” class. We first resampled the data to 1 km resolution by calculating the percent of the pixel occupied by grasslands. To avoid double counting land considered in other ecosystem protection solutions (Protect ForestsProtect Peatlands, and Protect Coastal Wetlands), we then adjusted the grassland map so that no pixel contained a value greater than 100% after summing all ecosystem types. These other ecosystems can overlap with grasslands either because they are non-exclusive (e.g., peatland soils can have grassland vegetation), or because of variable definitions (e.g., the grassland map allows up to 50% tree cover, which could be classified as a forest by other land cover maps). After adjusting for other ecosystems, we used the Terrestrial Ecoregions of the World data (Olson et al., 2001) to exclude areas of natural forest, because these areas are eligible for other solutions. 

The resultant raster of proportionate grassland coverage was converted to absolute areas, and used to calculate the total grassland area for each of four latitude bands (tropical: –23.4° to 23.4°; subtropical: –35° to –23.4° and 23.4° to 35°; temperate: –50° to –35° and 35° to 50°; boreal: <–50° and >50°). The analysis was conducted by latitude bands in order to retain some spatial variability in emissions factors and degradation rates. 

Protected Grassland Areas

We identified protected grassland areas using the World Database on Protected Areas (WDPA) (UNEP-WCMC and IUCN, 2024), which contains boundaries for each PA and additional information, including their establishment year and International Union for Conservation of Nature management category (Ia–VI, not applicable, not reported, and not assigned). The PA boundary data were converted to a raster and used to calculate the grassland area within PA boundaries for each latitude band and each PA category. To evaluate trends in adoption over time, we also aggregated protected areas by establishment year as reported in the WDPA. 

We used the maps of IPLs from Garnett et al. (2018) to identify IPLs that were not inside of established PAs. The total grassland area within IPLs was calculated according to the same process as for PAs.

Avoided Grassland Conversion

Broadly, we estimated annual, per-hectare emissions savings from grassland protection as the difference between net carbon exchange in a protected grassland and an unprotected grassland. This calculation followed Equation A1, in which the annual grassland loss avoided due to protection (%/yr) is multiplied by the 30-yr cumulative sum of emissions per hectare of grassland converted to cropland (CO₂‑eq /ha over 30 yr). 

left_text_column_width

Equation A1.

\[ Effectiveness = Grassland\text{ }loss_{avoided} \times \sum_{t=1}^{30}{Emissions} \]

The avoided grassland loss attributable to PAs was calculated from the source data for Figure 7 of Li et al. (2024), which provides the difference in habitat loss between protected areas and unprotected control areas between 2003–2019 by ecoregion. These data were filtered to only include grasslands, aggregated to latitude bands, and used to calculate annual linear rates of avoided habitat loss. Tropical and subtropical regions were not clearly distinguished, so the same rate was used for both.

Grassland Conversion Emissions

The emissions associated with grassland conversion to cropland include loss of above- and below-ground biomass carbon stocks, loss of soil carbon stocks, and loss of carbon sequestration potential. We used data on above- and below-ground biomass carbon stocks from Spawn et al. (2020) to calculate the average carbon stocks by latitude band for grassland pixels and cropland pixels. We used the 2010 ESA CCI land cover dataset for this calculation because it was the base map used to generate the biomass carbon stock dataset. The per-hectare difference between biomass carbon stocks in grasslands and croplands represents the emissions from biomass carbon stocks following grassland conversion.

We aggregated soil carbon stocks from SoilGrids 2.0 (0–30 cm depth) to latitude bands for grassland pixels from the 2015 ESA CCI land cover dataset, which was the base map used for the SoilGrids dataset (Poggio et al., 2021). To avoid capturing peatlands, which have higher C stocks, we excluded pixels with soil carbon contents >15% by mass (a slightly conservative cutoff for organic soils) prior to aggregation. We took the percent loss of soil carbon following grassland-to-cropland conversion from Table S8 of the meta-analysis by Huang et al. (2024), who also conducted their analysis by latitude band. Soil carbon losses are also associated with nitrous oxide emissions, which were calculated per the IPCC Tier 1 equations as follows using the default C:N ratio of 15:1. 

We calculated the loss of carbon sequestration potential based on estimates of grassland annual net CO₂ flux, extracted from Table S2 from Chang et al. (2021). These data include field- and model-based measurements of grassland net CO₂ flux and were used to calculate median values by latitude band.

left_text_column_width
Updated Date
Subscribe to Floods

Support Climate Action

Drawdown Delivered

Join the 85,000+ subscribers discovering how to drive meaningful climate action around the world! Every other week, you'll get expert insights, cutting-edge research, and inspiring stories.

Receive biweekly email newsletter updates from Project Drawdown. Unsubscribe at any time.