https://research-explorer.ista.ac.at 2000-01-01T00:00+00:00 1 monthly A unified framework of direct and indirect reciprocity https://research-explorer.ista.ac.at/record/9402 Schmid, Laura ; https://orcid.org/0000-0002-6978-7329 Chatterjee, Krishnendu ; https://orcid.org/0000-0002-4561-241X Hilbe, Christian ; https://orcid.org/0000-0001-5116-955X Nowak, Martin A. 2021 Direct and indirect reciprocity are key mechanisms for the evolution of cooperation. Direct reciprocity means that individuals use their own experience to decide whether to cooperate with another person. Indirect reciprocity means that they also consider the experiences of others. Although these two mechanisms are intertwined, they are typically studied in isolation. Here, we introduce a mathematical framework that allows us to explore both kinds of reciprocity simultaneously. We show that the well-known ‘generous tit-for-tat’ strategy of direct reciprocity has a natural analogue in indirect reciprocity, which we call ‘generous scoring’. Using an equilibrium analysis, we characterize under which conditions either of the two strategies can maintain cooperation. With simulations, we additionally explore which kind of reciprocity evolves when members of a population engage in social learning to adapt to their environment. Our results draw unexpected connections between direct and indirect reciprocity while highlighting important differences regarding their evolvability. https://research-explorer.ista.ac.at/record/9402 https://research-explorer.ista.ac.at/download/9402/14496 eng Springer Nature info:eu-repo/semantics/altIdentifier/doi/10.1038/s41562-021-01114-8 info:eu-repo/semantics/altIdentifier/e-issn/2397-3374 info:eu-repo/semantics/altIdentifier/wos/000650304000002 info:eu-repo/semantics/altIdentifier/pmid/33986519 info:eu-repo/semantics/openAccess Schmid L, Chatterjee K, Hilbe C, Nowak MA. A unified framework of direct and indirect reciprocity. <i>Nature Human Behaviour</i>. 2021;5(10):1292–1302. doi:<a href="https://doi.org/10.1038/s41562-021-01114-8">10.1038/s41562-021-01114-8</a> ddc:000 A unified framework of direct and indirect reciprocity info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 Assessing spatial patterns of carbon and nutrient dynamics in catchments of complex topography https://research-explorer.ista.ac.at/record/22438 Lian, Taiqi Fatichi, Simone Stähli, Manfred Bonetti, Sara 2025 The topography of a landscape regulates the spatial distribution of water and energy fluxes, which are main drivers of vegetation and soil carbon and nutrient dynamics. Despite the recognized role of topography in mediating such processes, quantifying and predicting the spatial distribution of carbon and nutrient fluxes and stocks in highly heterogeneous landscapes remains challenging. The main limitations stem from the prevalence of largely decoupled modeling approaches which fail to concurrently account for ecohydrological and biogeochemical processes as well as the lack of adequate frameworks describing the links among topography, water and energy balances, and soil biogeochemical dynamics. Here, we extend the capabilities of the mechanistic ecohydrological model Tethys-Chloris-Biogeochemistry (T&C-BG) by including a soil carbon and nutrient routing module in the distributed model version. The newly developed T&C-BG-2D model is validated against long-term hydrological and biogeochemical measurements from the Hafren catchment in Wales (UK) and the Erlenbach catchment in the Swiss pre-Alps. The model successfully captures carbon and nutrient concentrations and dynamics in these catchments, with relative differences between simulated and observed median values of between −4% and −0.3% for dissolved organic carbon, and between 1% and 20% for ammonia. A sensitivity analysis in the Erlenbach basin suggests that elevation explains over 80% of the observed spatial patterns, followed by topographic wetness index (12.6%), aspect (2.9%), and curvature (2.1%). These findings underscore topography's critical role in shaping water, carbon, and nutrient dynamics, which cannot be reflected in plot-scale simulations neglecting spatial interactions and topographic effects. https://research-explorer.ista.ac.at/record/22438 eng American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1029/2025wr040260 info:eu-repo/semantics/altIdentifier/issn/0043-1397 info:eu-repo/semantics/altIdentifier/e-issn/1944-7973 info:eu-repo/semantics/openAccess Lian T, Fatichi S, Stähli M, Bonetti S. Assessing spatial patterns of carbon and nutrient dynamics in catchments of complex topography. <i>Water Resources Research</i>. 2025;61(10). doi:<a href="https://doi.org/10.1029/2025wr040260">10.1029/2025wr040260</a> ddc:550 Assessing spatial patterns of carbon and nutrient dynamics in catchments of complex topography info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1