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Summary Long‐term pedogenesis leads to important changes in the availability of soil nutrients, especially nitrogen ( N ) and phosphorus ( P ). Changes in the availability of micronutrients can also occur, but are less well understood. We explored whether changes in leaf nutrient concentrations and resorption were consistent with a shift from N to P limitation of plant productivity with soil age along a > 2‐million‐year dune chronosequence in south‐western Australia. We also compared these traits among plants of contrasting nutrient‐acquisition strategies, focusing on N , P and micronutrients. The range in leaf P for individual species along the chronosequence was exceptionally large for both green (103–3000 μg P g −1 ) and senesced (19–5600 μg P g −1 ) leaves, almost equalling that found globally. From the youngest to the oldest soil, cover‐weighted mean leaf P declined from 1840 to 228 μg P g −1 , while P ‐resorption efficiency increased from 0% to 79%. All species converged towards a highly conservative P ‐use strategy on the oldest soils. Declines in cover‐weighted mean leaf N with soil age were less strong than for leaf P , ranging from 13.4 mg N g −1 on the youngest soil to 9.5 mg N g −1 on the oldest soil. However, mean leaf N ‐resorption efficiency was greatest (45%) on the youngest, N ‐poor soils. Leaf N : P ratio increased from 8 on the youngest soil to 42 on the oldest soil. Leaf zinc ( Z n) concentrations were low across all chronosequence stages, but mean Z n‐resorption efficiency was greatest (55–74%) on the youngest calcareous dunes, reflecting low Z n availability at high p H . N 2 ‐fixing species had high leaf N compared with other species. Non‐mycorrhizal species had very low leaf P and accumulated M n across all soils. We surmise that this reflects M n solubilization by organic acids released for P acquisition. Synthesis . Our results show community‐wide variation in leaf nutrient concentrations and resorption that is consistent with a shift from N to P limitation during long‐term ecosystem development. High Z n resorption on young calcareous dunes supports the possibility of micronutrient co‐limitation. High leaf M n on older dunes suggests the importance of carboxylate release for P acquisition. Our results show a strong effect of soil nutrient availability on nutrient‐use efficiency and reveal considerable differences among plants of contrasting nutrient‐acquisition strategies.
Hayes et al. (Tue,) studied this question.