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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 (Zn) concentrations were low across all chronosequence stages, but mean Zn‐resorption efficiency was greatest (55–74%) on the youngest calcareous dunes, reflecting low Zn availability at high pH. N₂‐fixing species had high leaf [N] compared with other species. Non‐mycorrhizal species had very low leaf [P] and accumulated Mn across all soils. We surmise that this reflects Mn 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 Zn resorption on young calcareous dunes supports the possibility of micronutrient co‐limitation. High leaf [Mn] 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.

Background Plant nutrient resorption is crucial for the efficient conservation of nutrients. However, the mechanisms through which abiotic and biotic factors control nutrient resorption remain controversial. We investigated leaf nitrogen (N) and phosphorus (P) resorption efficiency (NRE and PRE) and resorption proficiency, as well as the underlying mechanisms for each plant functional type (PFT: non-legume herbs, non-legume shrubs, and legumes) by collecting green and senescent leaves of 59 species covering 106 sites from arid and semiarid regions of northwest China. Results Legumes had much lower leaf NRE and much higher senesced leaf N than the other two PFTs; they had similar leaf PRE to non-legume shrubs. Non-legume herbs exhibited the highest leaf P resorption. Climate, particularly temperature, increased leaf N resorption in non-legume herbs; however, climate, particularly decreasing precipitation, decreased leaf P resorption in legumes. Leaf nutrient resorption in non-legume shrubs decreased with increasing soil fertility, but leaf NRE in legumes increased. Leaf traits contributed more to leaf N and P resorption than climate and soil. Senesced leaf N and P concentrations increased along the resource-conservative to resource-acquisitive strategy axis. There were strong negative relationships between leaf NRE and senesced leaf N concentration and between leaf PRE and senesced leaf P concentration, in which legumes had a lower slope than non-legumes. Conclusions These findings suggest that ecological strategies and N-fixing plant types modulate nutrient resorption. Plants with the resource-conservative strategy are highly proficient in nutrient resorption. We highlight the importance of leaf economics traits and spectrum in regulating leaf nutrient resorption in drylands in the context of global climate change, potentially modulating plant traits and community composition. The higher proficient and efficient N and P resorption of plant species suggests the crucial importance of nutrient resorption in the nutrient cycling of harsh drylands.

Nutrient resorption in plants influences nutrient availability and cycling and is a key process in biogeochemical models. Improved estimates of resorption parameters are needed for predicting long-term primary productivity and for improving such models. Currently, most models assume a value of 50% resorption for nitrogen (N) and phosphorus (P) and lack resorption data for other nutrients and for specific vegetation types. We provide global estimates of resorption efficiencies and nutrient concentrations for carbon (C), N, and P and the first global-scale estimates for essential nutrients such as potassium (K), calcium (Ca), and magnesium (Mg). We also examine leaf mass loss during senescence (LML) globally and for different plant types, thus defining a mass loss correction factor (MLCF) needed to quantify unbiased resorption values. We used a global meta-analysis of 86 studies and ∼1000 data points across climates for green and senesced leaves in six plant types: ferns, forbs, graminoids, conifers, and evergreen and deciduous woody angiosperms. In general, N and P resorption differed significantly from the commonly used global value of 50% (62.1%, 64.9%, respectively; P < 0.05). Ca, C, and Mg showed lower average resorptions of 10.9%, 23.2%, and 28.6%, respectively, while K had the highest resorption, at 70.1%. We also found that resorption of all nutrients except Ca depended on leaf nutrient-status; globally, C, N, P, K, and Mg showed a decrease in resorption with increased nutrient status. On average, global leaf mass loss was 24.2%. Overall, our resorption data differ substantially from commonly assumed values and should help improve ecological theory and biogeochemical and land-surface models.

Nutrient resorption from senescing leaves prior to litterfall is a strategy for nutrient conservation in vascular plants. However, the mechanisms through which soil fertility and/or foliar nutrient status affect nutrient resorption are not yet fully known. We used two 1,000‐m‐wide altitudinal gradients on two different bedrock types (carbonate and silicate) for analysing the interactive effects of temperature and soil chemistry on the resorption efficiency of two major nutrients, nitrogen (N) and phosphorus (P). Our objective was to assess how nutrient resorption varied across the gradients through the adaptation of individual species to changing environmental conditions rather than through changes in species composition. Both N and P resorption efficiency increased across the altitudinal gradients independent of bedrock type. The main process regulating nutrient resorption was a negative feedback to nutrient availability in the soil. The negative feedback of nutrient resorption efficiency to soil nutrient status was unrelated to total soil nutrient contents but depended on concentrations of organic N forms for nitrogen resorption efficiency (NRE) and on inorganic P forms for phosphorus resorption efficiency (PRE), respectively. While we hypothesized that the resorption of P, as a principally rock‐derived nutrient, depended on physical–chemical processes affected by soil chemistry, our results showed that microbial P mineralization was the main source of inorganic P supply to the plants. Both NRE and PRE were effective to improve the growth potential of plants, but there was no evidence of stoichiometric adaptations of N:P RE‐to‐nutrient ratio in the soil. A plain language summary is available for this article. Plain Language Summary

Background and aims How nitrogen deposition and increasing precipitation would affect leaf nutrient concentration and internal nutrient cycling of desert plants is still unclear. The aim of our study was to test the responses of leaf nutrient resorption to increasing precipitation and N enrichment in a temperate desert. Methods Green and senesced leaf nitrogen and phosphorus concentrations, and nitrogen (NRE) and phosphorus (PRE) resorption efficiency of three life-form plants (5 spring annuals, 2 summer annuals and 2 shrubs) were investigated. Results Both NRE and PRE showed remarkable variations among plant life-forms, being lowest in shrubs and highest in spring annuals, suggesting that plants may have different nutrient requiring strategies. Nitrogen addition promoted green and senesced leaf nitrogen concentrations in summer annuals and shrubs, while having no impacts on leaf phosphorus concentration, NRE and PRE. Water addition had no impacts on leaf nutrient concentration and resorption efficiency; combined nitrogen and water addition had no interactive effects. Conclusions Our results suggest that spring annuals and shrubs exhibit conservative nutrient adaptation through increasing nutrient uptake but not changing nutrient internal cycle to increasing nitrogen and water.

Aim: Trees associating with ectomycorrhizal (ECM) fungi typically occur in infertile soils and use nutrients more conservatively than arbuscular mycorrhizal (AM) trees. We hypothesized that ECM trees would have greater nutrient resorption (i.e., proportion of nutrients resorbed during leaf senescence) than AM trees. Location: Global. Methods: We synthesized nitrogen (N) and phosphorus (P) resorption data from 378 species from sub/tropical, temperate and boreal forests, including 43 studies where ECM and AM trees co-occurred, and conducted a meta-analysis. Additionally, we quantified N resorption in 45 plots varying in ECM-AM tree abundances in the temperate deciduous forests of southern Indiana, USA. Results: Overall, resorption patterns were driven primarily by mycorrhizal type, climate zone, and to a lesser degree, leaf habit. In the boreal forest, P resorption was 76% greater for ECM than AM trees (p < .05). In the sub/tropics, AM trees resorbed 30% more N than ECM trees. At the sites where AM and ECM trees co-occurred, ECM trees resorbed more N in temperate forests (15% greater; p < .001) whereas AM trees tended to resorb more N in sub/tropical forests (by 29%; p = .08). Besides, deciduous ECM trees resorbed more N (10%) and P (15%) than deciduous AM trees, while evergreen ECM and AM trees did not differ. In the deciduous forests of Indiana, where ECM and AM trees co-occurred, the relative abundance of ECM trees in a plot was positively correlated to plot-scale N resorption (R2 = .25, p = .001), indicating greater nutrient conservatism with increasing ECM-dominance. Main conclusions: Our results indicate that mycorrhizal association – in addition to other factors – is correlated with the degree to which trees recycle nutrients, with the strongest effects occurring for N resorption by temperate deciduous trees.

Background and aims Global warming is a major global issue that may affect nutrient cycling in terrestrial ecosystems. Plants usually employ the strategy of nutrient resorption to conserve resources. Over the past few decades, there has been widespread attention given to how warming affects the nutrient resorption efficiency (NuRE) in leaves. Twig is another important component of plant. The unique physiological characteristics of twig may make its NuRE response to warming different from that of leaf. However, there is insufficient knowledge regarding how warming affects NuRE in twigs. Methods We assessed the response of nutrient concentrations (nitrogen, phosphorus, potassium, calcium, and magnesium) and NuREs in leaves and twigs to warming, by using plant samples ( Cunninghamia lanceolata ) from a manipulative field warming experiment (+ 5 °C). Results The nutrient concentrations and NuREs of leaves remained unchanged under warming. In contrast, warming significantly decreased nitrogen concentration (− 13%) and increased calcium (+ 21%) and magnesium (+ 44%) concentrations in mature twigs. Warming significantly decreased NRE (− 10%), KRE (− 15%), and CaRE (− 7%), and increased MgRE (+ 12%) in twigs. It was also found that warming decreased the water content of twigs, and there were significant negative correlations between NuREs and nutrients in senesced organs. Conclusion The nutrient concentrations and NuRE of twigs are more vulnerable to warming than those of leaves. The regulation of NuRE response to warming is influenced by water and nutrients. Incorporating plant twig NuRE into nutrient cycling modeling and ecosystem productivity predictions may improve the accuracy of predictions under future warming conditions.

Nutrient resorption is a fundamental process through which plants withdraw nutrients from leaves before abscission. Nutrient resorption patterns have the potential to reflect gradients in plant nutrient limitation and to affect a suite of terrestrial ecosystem functions. Here, we used a stoichiometric approach to assess patterns in foliar resorption at a variety of scales, specifically exploring how N : P resorption ratios relate to presumed variation in N and/or P limitation and possible relationships between N : P resorption ratios and soil nutrient availability. N : P resorption ratios varied significantly at the global scale, increasing with latitude and decreasing with mean annual temperature and precipitation. In general, tropical sites (absolute latitudes < 23°26′) had N : P resorption ratios of < 1, and plants growing on highly weathered tropical soils maintained the lowest N : P resorption ratios. Resorption ratios also varied with forest age along an Amazonian forest regeneration chronosequence and among species in a diverse Costa Rican rain forest. These results suggest that variations in N : P resorption stoichiometry offer insight into nutrient cycling and limitation at a variety of spatial scales, complementing other metrics of plant nutrient biogeochemistry. The extent to which the stoichiometric flexibility of resorption will help regulate terrestrial responses to global change merits further investigation.

   Aims Investigations into the nutrient contents and changes in the stoichiometry and nutrient resorption strategies of different original forests during their development are of great significance toward the establishment of healthy, high-quality forest ecosystems. Methods A total of 24 sample plots with age gradients were established in natural Larix principis-rupprechtii forests and plantations, from which mature and senescent leaves, new branches, fine roots, and soil were collected and analyzed. The carbon (C), nitrogen (N), and phosphorus (P) contents were determined, and the stoichiometric ratios and resorption efficiencies were calculated. Results and conclusions The soil organic carbon and total nitrogen of the forests accumulated with advancing age, whereas the total phosphorus decreased because of higher consumption. Plantation trees tended to reduce the storage of nutrients in inactive plant structures to prevent nutrient loss, whereas natural forest trees maintained a stable nutrient concentration within their active organs. Plantation and natural forest trees adopted highly conservative N and P utilization strategies through improved resorption efficiencies. However, plantation forests were more conservative than their natural counterparts. The mature leaves, litter, branches, and fine roots of natural forests were influenced to a greater degree by the soil P, whereas those of plantation forests were more affected by the soil N. Nutrient concentrations within the active organs of plantation trees were more strongly dependent on soil than natural forests. We considered that natural forests likely possessed a more extensive range of strategies to deal with the variable compositions and concentrations of soil nutrients, which might strengthen their resilience against the effects of aging.

Aim Leaf nutrient resorption is a key nutrient conservation trait, which also influences nutrient cycling rates and pools. Most global biogeochemical models assume that resorption is non‐varying at a temporal scale. However, this trait can differ substantially within populations among years. We assessed the commonality of attaining proficient resorption, the factors associated with proficient resorption, as well as the variability of this trait and the factors controlling trait variability. Location Global. Time period 1965–2009. Major taxa studied Plants. Methods We compiled multi‐year nutrient resorption data from the literature, representing 50 studies, 94 unique study locations, and 141 species from 53 families and 29 orders. We used multiple linear regression to relate resorption data, as well as the variability in this trait, expressed as the coefficient of variation, to environmental factors. Results Resource availability was a key driver of resorption, with nutrient‐poor soils associated with more complete resorption and lower resorption plasticity. Nitrogen and phosphorus resorption differentially responded to some drivers, such as leaf habit, soil order and mycorrhizal status. Main conclusions Overall, environmental and biological factors representing a strong selective force for nutrient conservation, such as nutrient‐poor soil orders, semi‐arid soil moisture regimes, or lack of plant mutualists, were associated with complete resorption, whereas incomplete resorption was associated with weak selective forces, such as nutrient‐rich soil orders, or factors impeding this physiological process (e.g., drought). Inter‐annual variability in resorption was common, particularly for phosphorus. This plasticity has implications for ecosystem nutrient cycling and plant productivity, and accounting for this plasticity in dynamic models of nutrient cycling will improve predictions of nutrient limitations and productivity under future climate conditions.