• Energy Research

This research was funded by the European Research Council (ERC Grant agreement 647038, BIODESERT), the Spanish Ministry of Science and Innovation (PID2020-116578RB-I00) and Generalitat Valenciana (CIDEGENT/2018/041), with additional support by the University of Alicante (UADIF22-74 and VIGROB22-350). F.T.M. acknowledges support from the King Abdullah University of Science and Technology (KAUST) and the KAUST Climate and Livability Initiative. D.J.E. is supported by the Hermon Slade Foundation. H.S. is supported by a María Zambrano fellowship funded by the Ministry of Universities and European Union-Next Generation plan. L.W. acknowledges support from the US National Science Foundation (EAR 1554894). B.B. and S.S. were supported by the Taylor Family–Asia Foundation Endowed Chair in Ecology and Conservation Biology. M.B. acknowledges support from a Ramón y Cajal grant from the Spanish Ministry of Science (RYC2021-031797-I). A.L. and L.K. acknowledge support from the German Research Foundation, DFG (grant CRC TRR228) and German Federal Government for Science and Education, BMBF (grants 01LL1802C and 01LC1821A). L.K. acknowledges travel funds from the Hans Merensky Foundation. A.N. and C. Branquinho acknowledge support from FCT—Fundação para a Ciência e a Tecnologia (CEECIND/02453/2018/CP1534/CT0001, PTDC/ASP-SIL/7743/2020, UIDB/00329/2020), from AdaptForGrazing project (PRR-C05-i03-I-000035) and from LTsER Montado platform (LTER_EU_PT_001). S.C.R. was supported by NASA (NNH22OB92A) and is grateful to E. Geiger, A. Howell, R. Reibold, N. Melone and M. Starbuck for field support. Any use of trade, firm or product names is for descriptive purposes only and does not imply endorsement by the US Government. We thank the landowners for granting access to the sites and many people and their institutions for supporting our fieldwork activities: L. Eloff, J. J. Jordaan, E. Mudongo, V. Mokoka, B. Mokhou, T. Maphanga, D. Thompson (SAEON), A. S. K. Frank, R. Matjea, F. Hoffmann, C. Goebel, the University of Limpopo, South African Environmental Observation Network (SAEON), the South African Military and the Scientific Services Kruger National Park. Mineral-associated organic carbon (MAOC) constitutes a major fraction of global soil carbon and is assumed less sensitive to climate than particulate organic carbon (POC) due to protection by minerals. Despite its importance for long-term carbon storage, the response of MAOC to changing climates in drylands, which cover more than 40% of the global land area, remains unexplored. Here we assess topsoil organic carbon fractions across global drylands using a standardized field survey in 326 plots from 25 countries and 6 continents. We find that soil biogeochemistry explained the majority of variation in both MAOC and POC. Both carbon fractions decreased with increases in mean annual temperature and reductions in precipitation, with MAOC responding similarly to POC. Therefore, our results suggest that ongoing climate warming and aridification may result in unforeseen carbon losses across global drylands, and that the protective role of minerals may not dampen these effects. 19 páginas total artículo.- 3 figuras.- 33 referencias y 4 figuras.- 2 tablas.- 68 referencias.- The online version contains supplementary material available and extended data is available for this paper at https://doi.org/10.1038/s41558-024-02087-y No

Increases in the abundance of woody species have been reported to affect the provisioning of ecosystem services in drylands worldwide. However, it is virtually unknown how multiple biotic and abiotic drivers, such as climate, grazing, and fire, interact to determine woody dominance across global drylands. We conducted a standardized field survey in 304 plots across 25 countries to assess how climatic features, soil properties, grazing, and fire affect woody dominance in dryland rangelands. Precipitation, temperature, and grazing were key determinants of tree and shrub dominance. The effects of grazing were determined not solely by grazing pressure but also by the dominant livestock species. Interactions between soil, climate, and grazing and differences in responses to these factors between trees and shrubs were key to understanding changes in woody dominance. Our findings suggest that projected changes in climate and grazing pressure may increase woody dominance in drylands, altering their structure and functioning.

SignificanceIdentifying species assemblages that boost the provision of multiple ecosystem functions simultaneously (multifunctionality) is crucial to undertake effective restoration actions aiming at simultaneously promoting biodiversity and high multifunctionality in a changing world. By disentangling the effect of multiple traits on multifunctionality in a litter decomposition experiment, we show that it is possible to identify the assemblages that boost multifunctionality across multiple species mixtures originating from six biomes. We found that higher evenness among dissimilar species and the functional attributes of rare species as key biodiversity attributes to enhance multifunctionality and to reduce the abundance of plant pathogens. Our study identifies those species assemblages needed to simultaneously maximize multifunctionality and limit plant disease risks in natural and managed ecosystems.

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