20:T447,• Across species, leaf lifespan (LL) tends to be correlated with leaf mass per area (LMA). Previously we found that Australian perennial species from low-rainfall sites had c . 40% shorter LL at a given LMA than high-rainfall species. • Here we relate indices of leaf strength (work to shear, W _shear , and tissue toughness) to LL and LMA across the same suite of species. W _shear is the work required to cut a leaf with a blade; W _shear divided by leaf thickness gives tissue toughness. • Low- and high-rainfall species did not differ in their LL at a given W _shear , but dry-site species had lower W _shear at a given LMA, leading to the observed LL - LMA shift with rainfall. These patterns were driven by 50% lower tissue toughness in dry-site species. • The lower toughness was linked with high leaf N concentration, which is known to enhance water conservation during photosynthesis in low-rainfall species. Our results suggest that a significant cost of this strategy is reduced LL for a given investment in leaf tissue (LMA).21:T45b,• Associations between specific leaf area (SLA), leaf water content (LWC) and leaf thickness (LT) in 77 species were analysed to identify which of these traits gave a better indicator value of general plant resource-use strategy within the flora of central-western Argentina, in which succulent species are common. • When all species were considered together, SLA and LWC were not significantly correlated. All high-SLA tender-leafed species showed high LWC. Low SLA, however, was associated both with low LWC (sclerophyllous species) and with high LWC (succulents). When succulents were excluded, the association between SLA and LWC was significant and positive. A similar trend was found for a mixed set of nonsucculent species from other floras of the world. • In the Argentine data set, SLA and LT, but not LWC, were significantly correlated with species’ scores along a multivariate axis of plant resource-use strategy. • Because of its clearer ecological interpretation and its applicability across different floras, SLA appears to be the best candidate for inclusion in large comparative databases.22:T910,

	Year	Citations

References