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7 pags., 4 figs., 3 pags. ; The Dzyaloshinskii-Moriya interaction (DMI) is an antisymmetric exchange interaction that stabilizes chiral spin textures. It is induced by inversion symmetry breaking in noncentrosymmetric lattices or at interfaces. Recently, interfacial DMI has been found in magnetic layers adjacent to transition metals due to the spin-orbit coupling and at interfaces with graphene due to the Rashba effect. We report direct observation of strong DMI induced by chemisorption of oxygen on a ferromagnetic layer at room temperature. The sign of this DMI and its unexpectedly large magnitude—despite the low atomic number of oxygen—are derived by examining the oxygen coverage–dependent evolution of magnetic chirality. We find that DMI at the oxygen/ ferromagnet interface is comparable to those at ferromagnet/transition metal interfaces; it has enabled direct tailoring of skyrmion's winding number at room temperature via oxygen chemisorption. This result extends the understanding of the DMI, opening up opportunities for the chemisorption-related design of spin-orbitronic devices. ; This work has been supported by the NSF (DMR-1610060 and DMR-1905468) and the UC Office of the President Multicampus Research Programs and Initiatives (MRP-17- 454963). Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under contract no. DE-AC02- 05CH11231. Work at GU has been supported, in part, by SMART (2018-NE-2861), one of seven centers of nCORE, a Semiconductor Research Corporation program, sponsored by the National Institute of Standards and Technology (NIST). A.M. and M.A.G.B. acknowledge support from MINECO (Spain) under the project no. MAT2017-87072-C4-2-P and from Comunidad de Madrid under the project no. S2018/NMT4321. The Jülich team acknowledges financial support from the DARPA TEE program through grant MIPR (# HR0011831554) from the DOI, the European Union H2020-INFRAEDI-2018-1 program (grant no. 824143, project "MaX— Materials at the exascale"), the Deutsche Forschungsgemeinschaft (DFG) through SPP 2137 "Skyrmionics" (project BL 444/16), the Collaborative Research Centers SFB 1238 (project C01), and computing resources at the supercomputers JURECA at Juelich Supercomputing Centre and JARA-HPC from RWTH Aachen University (projects jias1f and jara0197). R.L.C., A.K.S., and R.W. acknowledge financial support from the European Union via an International Marie Curie Fellowship (grant no. 748006). H.D. acknowledges the support of the National Key R&D Program of China (grant no. 2017YFA0303202) and the National Natural Science Foundation of China (grant nos. 11734006 and 51571109). E.G.M. acknowledges support from MINECO (Spain) under grants MAT2014-52477 and FIS2017-82415-R and from MECD (Spain) under grant PRX17/00557

A need for multi-functional assessment tools evaluating trade-offs and co-benefits for various types of Nature-Based Solutions (NBS) has been increasingly identified in recent years. Methodologically, concepts for a tool are presented which include quantifying the demand and potential for NBS to enhance ecosystem service (ES) provision, and linking ESs to readily quantifiable and legislatively-relevant environmental quality indicators (EQIs). The objective of tool application is to identify optimal NBS placement across a diverse set of socio-environmental indicators, whilst also incorporating issues of relative location of areas of implementation and benefit accrual. Embedded within the tool is the importance of evaluating outcomes in terms of economic benefits and of sustainable development goals. The concepts are illustrated with simplified examples, relating to the case of implementing urban forestry as an exemplar NBS. By summarising the knowledge base it is demonstrated that benefits of NBS are substantially scale-dependent in two main respects; those of extent and proximity to receptors. Evaluation tools should be capable of quantifying scale-dependence. The substantive importance of these considerations and how their dynamics vary between indicators and services is illustrated graphically through schematic functions. When developed, the tool should be used as a focus for consultation and co-design to pinpoint the size of NBS necessary to achieve a sufficient level of benefit for a particular receptor. This could be measured against target levels of benefit for each indicator, distinguishing between primary intended outcomes and those co-benefits or trade-offs that are secondary or unintended.