Nitrogen use strategy drives interspecific differences in plant photosynthetic CO₂ acclimation

Abstract

Rising atmospheric CO2 concentration triggers an emergent phenomenon called plant photosynthetic acclimation to elevated CO2 (PAC). PAC is often characterized by a reduction in leaf photosynthetic capacity (Asat), which varies dramatically along the continuum of plant phylogeny. However, it remains unclear whether the mechanisms responsible for PAC are also different across plant phylogeny, especially between gymnosperms and angiosperms. Here, by compiling a dataset of 73 species, we found that although leaf Asat increased significantly from gymnosperms to angiosperms, there was no phylogenetic signal in the PAC magnitude along the phylogenetic continuum. Physio‐morphologically, leaf nitrogen concentration (Nm), photosynthetic nitrogen‐use efficiency (PNUE), and leaf mass per area (LMA) dominated PAC for 36, 29, and 8 species, respectively. However, there was no apparent difference in PAC mechanisms across major evolutionary clades, with 75% of gymnosperms and 92% of angiosperms regulated by the combination of Nm and PNUE. There was a trade‐off between Nm and PNUE in driving PAC across species, and PNUE dominated the long‐term changes and inter‐specific differences in Asat under elevated CO2. These findings indicate that nitrogen‐use strategy drives the acclimation of leaf photosynthetic capacity to elevated CO2 across terrestrial plant species.

Effects of nitrogen addition and Bothriochloa ischaemum and Lespedeza davurica mixture on plant chlorophyll fluorescence and community production in semi-arid grassland

“…The effective nitrogen input promoted the production of plant photochemical reaction enzymes and chlorophyll, and increased plant photosynthesis ( Guidi et al., 2019 ). Complementary utilization of nutrients by B.ischaemum and L.davurica in the community significantly increased the photosynthetic efficiency, but the effect of N on community AGB was counteracted due to the difference between the two species’ photosynthetic strategies ( Cui et al., 2023 ). This discrepancy may arise because the ΦPSII and qP of L.davurica were higher than B.ischaemum , and the photosynthetic center passively received more light energy under the mixture and N addition combined influence, resulting in damage to the photosynthetic apparatus ( White and Critchley, 1999 ).…”

Trait–environment relationships are timescale dependent

“…The global distribution of plant traits is predominantly influenced by evolutionary history, which shapes the legacy of traits in lineages. Simultaneously, environmental filtering plays a crucial role by selecting traits that confer advantages in specific ecological contexts (Cui et al ., 2023). However, in current trait–environment modeling, the role of phylogenetic relationships remains unexplored.…”

“Nitrogen demand, supply, and acquisition strategy control plant responses to elevated CO2at different scales”

“…Such optimal leaf nitrogen allocation responses to elevated CO2 increases photosynthetic nitrogen-use efficiency and allows increased net photosynthesis rates to be achieved through increasingly equal co-limitation of Rubisco carboxylation and electron transport for RuBP regeneration (Chen et al, 1993;Maire et al, 2012;Wang et al, 2017;Smith et al, 2019). The expected optimal leaf response to elevated CO2 has received some empirical support (Crous et al, 2010;Lee et al, 2011;Harrison et al, 2021;Dong et al, 2022b;Cui et al, 2023), though no studies have connected these patterns with concurrently measured whole-plant responses.…”