Higher leaf nitrogen content is linked to tighter stomatal regulation of transpiration and more efficient water use across dryland trees.

ABSTRACT: The least-cost economic theory of photosynthesis shows that water and nitrogen are mutually substitutable resources to achieve a given carbon gain. However, vegetation in the Sahel has to cope with the dual challenge imposed by drought and nutrient-poor soils. We addressed how variation in leaf nitrogen per area (N_area ) modulates leaf oxygen and carbon isotopic composition (δ¹⁸ O, δ¹³ C), as proxies of stomatal conductance and water-use efficiency, across 34 Sahelian woody species. Dryland species exhibited diverging leaf δ¹⁸ O and δ¹³ C values, indicating large interspecific variation in time-integrated stomatal conductance and water-use efficiency. Structural equation modeling revealed that leaf N_area is a pivotal trait l

SUBMITTER: Querejeta JI 

PROVIDER: S-EPMC9542767 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature