Biocrusts buffer against the accumulation of soilmetallic nutrients induced by warmingand rainfall reduction

The availability of metallic nutrients in dryland soils, many of which are essential for the metabolism of soil organisms and vascular plants, may be altered due to climate change-driven increases in aridity. Biocrusts, soil surface communities dominated by lichens, bryophytes and cyanobacteria, are ecosystem engineers known to exert critical functions in dryland ecosystems. However, their role in regulating metallic nutrient availability under climate change is uncertain. Here, we evaluated whether well-developed biocrusts modulate metallic nutrient availability in response to 7 years of experimental warming and rainfall reduction in a Mediterranean dryland located in southeastern Spain. We found increases in the availability of K, Mg, Zn and Na under warming and rainfall exclusion. However, the presence of a well-developed biocrust cover buffered these effects, most likely because its constituents can uptake significant quantities of available metallic nutrients. Our findings suggest that biocrusts, a biotic community prevalent in drylands, exert an important role in preserving and protecting metallic nutrients in dryland soils from leaching and erosion. Therefore, we highlight the need to protect them to mitigate undesired effects of soil degradation driven by climate change in this globally expanding biome. Eduardo Moreno-Jimenez et al. experimentally manipulate rainfall and temperature in a Mediterranean dryland to explore the association of biocrusts with essential metallic nutrients. They find that biocrusts-communities of lichens, bryophytes and cyanobacteria on the soil surface-can buffer against the effects of warming and reduced rainfall on metallic nutrient availability

Soils in warmer and less developed countries have less micronutrients globally

Soil micronutrients are capital for the delivery of ecosystem functioning and food provision worldwide. Yet, despite their importance, the global biogeography and ecological drivers of soil micronutrients remain virtually unknown, limiting our capacity to anticipate abrupt unexpected changes in soil micronutrients in the face of climate change. Here, we analyzed >1300 topsoil samples to examine the global distribution of six metallic micronutrients (Cu, Fe, Mn, Zn, Co and Ni) across all continents, climates and vegetation types. We found that warmer arid and tropical ecosystems, present in the least developed countries, sustain the lowest contents of multiple soil micronutrients. We further provide evidence that temperature increases may potentially result in abrupt and simultaneous reductions in the content of multiple soil micronutrients when a temperature threshold of 12–14°C is crossed, which may be occurring on 3% of the planet over the next century. Altogether, our findings provide fundamental understanding of the global distribution of soil micronutrients, with direct implications for the maintenance of ecosystem functioning, rangeland management and food production in the warmest and poorest regions of the planet.The sampling included in this study were supported by the European Research Council (ERC) grant 647038 (BIODESERT), the BES grant agreement No. LRB17\1019 (MUSGONET) and the Marie Skłodowska-Curie grant agreement 702057 (CLIMIFUN). We would like to thank the researchers originally involved in the BIODESERT, CLIMIFUN and MUSGONET projects for their help with samplings. E.M.-J. acknowledges the Humboldt Foundation for supporting his research stay in Germany (Fellowship for Experienced Researchers) and a project from the Spanish Ministry of Science and Innovation (PID2020-116578RB-I00). M.D.-B. is supported by a Ramón y Cajal grant (RYC2018-025483-I), a project from the Spanish Ministry of Science and Innovation (PID2020-115813RA-I00) and a project PAIDI 2020 from the Junta de Andalucía (P20_00879). E.G. is supported by the Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital de la Generalitat Valenciana, and the European Social Fund grant APOSTD/2021/188 and European Research Council (ERC) grant 647038. F.T.M. is supported by European Research Council (ERC) grant 647038 and Generalitat Valenciana grant CIDEGENT/2018/041. M.D. and T.W.C. were funded by the Marc R. Benioff Revocable Trust and in collaboration with the World Economic Forum. This article is part of the contract between ETH Zurich and University of Alicante “Mapping terrestrial ecosystem structure at the global scale”. R.O.H. is supported by the Ramón y Cajal program from the MICINN (RYC-2017 22032), a PAIDI 2020 project from the Junta de Andalucía (Ref. 20_00323) and a project from the Spanish Ministry of Science and Innovation (PID2019-106004RA-I00/AEI/10.13039/501100011033). Authors acknowledge support by the Open Access Publication Initiative of Freie Universität Berlin. Open Access funding enabled and organized by Projekt DEAL

Transplanting the leafy liverwort Herbertus hutchinsiae : A suitable conservation tool to maintain oceanic-montane liverwort-rich heath?

Thanks to the relevant landowners and managers for permission to carry out the experiments, Chris Preston for helping to obtain the liverwort distribution records and the distribution map, Gordon Rothero and Dave Horsfield for advice on choosing experimental sites and Alex Douglas for statistical advice. Juliane Geyer’s help with fieldwork was greatly appreciated. This study was made possible by a NERC PhD studentship and financial support from the Royal Botanic Garden Edinburgh and Scottish Natural Heritage.Peer reviewedPostprin

Codonoblepharonteae, a New Major Lineage among Orthotrichoideae (Orthotrichaceae, Bryophyta)

Orthotrichoideae aggregates epiphytic mosses widespread throughout temperate regions and high tropical mountains of the world. Recently, important advances have been made in elucidating its phylogenetic relationships and evolutionary patterns. Fourteen genera are currently recognized within the subfamily, which are spread over two main tribes: Orthotricheae, comprising Orthotrichinae and Lewinskyinae, and Zygodonteae. Despite the progress, some groups have received little attention, as is the case of genus Codonoblepharon. Recent studies have suggested that this genus may represent a separate lineage from Zygodonteae, in which it traditionally has been considered. Although, none of the studies were conclusive as they did not include a representative sampling of the Codonoblepharon species. This work aims to evaluate the taxonomic position of Codonoblepharon and its phylogenetic relationships within Orthotrichoideae. For this purpose, we present an updated phylogenetic tree based on four different loci, one belonging to the nuclear genome (ITS2) and the rest to the plastid genome (rps4, trnG and trnL-F). The phylogenetic reconstruction recovers all samples of Codonoblepharon in a monophyletic group, sister to the rest of the subfamily, constituting a lineage independent of the two currently recognized tribes. For this reason, we propose the new tribe Codonoblepharonteae to accommodate Codonoblepharon