Divergent respiration–trait relationships reveal a unique economic strategy in ferns

PREMISE: ), remain scarce for ferns, and no study has systematically compared respiration-trait relationships between ferns and seed plants. METHODS: ), leaf N and P content, leaf dry mass per unit area (LMA), and leaf dry mass content (LDMC) in 19 ferns. These fern data were analyzed in comparison with seed plant data from the Glopnet data set. RESULTS: , jointly explaining 70.6% of its variation. CONCLUSIONS: The terrestrial understory ferns employ a distinct "low-cost, slow-cycling" strategy-characterized by a unique combination of low leaf construction cost (LMA) and low metabolic rates (photosynthesis and respiration), which deviates from the traditional fast-slow leaf economics spectrum. The divergent respiration-trait relationships suggest that applying trait-based models parameterized solely for seed plants to ferns may introduce uncertainty into ecosystem models. This highlights the value of incorporating fern-specific trait relationships to refine projections of the global carbon cycle.