Leaf phosphorus resorption is related to leaf lifespan and labile phosphorus allocation among species in a nutrient‐poor sclerophyll woodland

Internal nutrient recycling, such as leaf nutrient resorption, serves as an important strategy for plants to optimise their growth and survival on nutrient‐poor soils. Phosphorus resorption efficiency (P RE ) varies widely (20%–90%) among species living on P‐poor soils. However, the key drivers behind this local variation are poorly understood. We hypothesised that two traits would drive variation in P RE among species at a site characterised by chronically low soil P (total soil P of 84 ppm): leaf lifespan (LL) and the proportion of leaf P in ‘labile’ fractions that are easily resorbed. Labile P concentration, P labile , is comprised of inorganic phosphates and soluble phosphorylated metabolites. To test this hypothesis and gain a wider understanding of how leaf nutrient resorption varies locally, we quantified a set of related traits for 14 common woody species in a species‐rich but nutrient‐poor sclerophyll woodland community at Davies Park in the Blue Mountains, NSW, Australia. These traits were LL, P labile , green and senesced leaf N and P concentrations and P resorption efficiency (P RE ). Supporting our hypothesis, LL explained >50% variation in leaf P RE . Similarly, P RE was strongly and positively associated ( R 2 > 60%) with the allocation of green leaf P to P labile . The LL‐P RE relationship was mainly driven by lower senesced leaf P than green leaf P. The local soil P availability explained 60% variation in green leaf P. Overall, this study highlights the combination of traits leading to greater internal recycling of P, including high P RE , long LL and high allocation of leaf P to P labile , in species‐rich, nutrient‐poor ecosystems. Read the free Plain Language Summary for this article on the Journal blog.