{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T10:18:50Z","timestamp":1785406730280,"version":"3.56.0"},"reference-count":61,"publisher":"National Academy of Sciences","issue":"23","license":[{"start":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T00:00:00Z","timestamp":1780617600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100024950","name":"NNF | Novo Holdings","doi-asserted-by":"publisher","award":["NNF 21OC0068884"],"award-info":[{"award-number":["NNF 21OC0068884"]}],"id":[{"id":"10.13039\/501100024950","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[2026,6,9]]},"abstract":"<jats:p>\n                    To improve crop yield and resilience, it is essential to identify the steps limiting\n                    <jats:inline-formula>\n                      <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" overflow=\"scroll\">\n                        <mml:mrow>\n                          <mml:mi>C<\/mml:mi>\n                          <mml:msub>\n                            <mml:mi>O<\/mml:mi>\n                            <mml:mn>2<\/mml:mn>\n                          <\/mml:msub>\n                        <\/mml:mrow>\n                      <\/mml:math>\n                    <\/jats:inline-formula>\n                    assimilation rate in plant leaves. The combined effect of multiple traits can be resolved by mechanistic models of the underlying diffusion, biochemistry, and geometry. Yet the widely used simple serial resistance models overlook tissue geometry, and detailed anatomical models are computationally heavy and rely on parameters that are difficult to measure. Here, we develop a framework for systematic species and model comparison, and find that the necessary level of model resolution is species-specific. We apply a minimal reaction\u2013diffusion model and reduce\n                    <jats:inline-formula>\n                      <mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"inline\" overflow=\"scroll\">\n                        <mml:mrow>\n                          <mml:mi>C<\/mml:mi>\n                          <mml:msub>\n                            <mml:mi>O<\/mml:mi>\n                            <mml:mn>2<\/mml:mn>\n                          <\/mml:msub>\n                        <\/mml:mrow>\n                      <\/mml:math>\n                    <\/jats:inline-formula>\n                    fixation in leaves to two key parameters. These parameters comprise a compact phase space in which three rate-limiting regimes emerge naturally: stomatal uptake, intercellular diffusion, and intracellular processes. Mapping diverse plant species into this phase space reveals: 1) dominant colimitations by stomatal and intracellular processes, 2) an equal partition between species that require spatially resolved leaf-scale models and species where intracellular models suffice. Taken together, we present a scalable path for interpreting complex trait data and bridging between models.\n                  <\/jats:p>","DOI":"10.1073\/pnas.2609915123","type":"journal-article","created":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T18:11:32Z","timestamp":1780683092000},"update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":0,"title":["Mapping\n                    <i>CO<\/i>\n                    <sub>2<\/sub>\n                    fixation to two effective parameters: A framework toward data-informed species and model comparison"],"prefix":"10.1073","volume":"123","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-4511-6894","authenticated-orcid":false,"given":"Andreas","family":"Stillits","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/035b05819","id-type":"ROR","asserted-by":"publisher"}],"name":"Biocomplexity, Niels Bohr Institute, University of Copenhagen","place":["Copenhagen, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teresa E.","family":"Knudsen","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/035b05819","id-type":"ROR","asserted-by":"publisher"}],"name":"Biocomplexity, Niels Bohr Institute, University of Copenhagen","place":["Copenhagen, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1945-454X","authenticated-orcid":false,"given":"Ala","family":"Trusina","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/035b05819","id-type":"ROR","asserted-by":"publisher"}],"name":"Biocomplexity, Niels Bohr Institute, University of Copenhagen","place":["Copenhagen, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[2026,6,5]]},"reference":[{"key":"e_1_3_4_1_2","doi-asserted-by":"publisher","DOI":"10.1146\/annurev-arplant-042809-112206"},{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.xplc.2020.100032"},{"key":"e_1_3_4_3_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.aai8878"},{"key":"e_1_3_4_4_2","doi-asserted-by":"crossref","unstructured":"F. 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Deposited 18 March 2026."}],"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.2609915123","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T18:11:46Z","timestamp":1780683106000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/10.1073\/pnas.2609915123"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,5]]},"references-count":61,"journal-issue":{"issue":"23","published-print":{"date-parts":[[2026,6,9]]}},"alternative-id":["10.1073\/pnas.2609915123"],"URL":"https:\/\/doi.org\/10.1073\/pnas.2609915123","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,5]]},"assertion":[{"value":"2026-03-31","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-05-11","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-06-05","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e2609915123"}}