How Nitrogen and Phosphorus Availability Change Water Use Efficiency in a Mediterranean Savanna Ecosystem

Nutrient availability, especially of nitrogen (N) and phosphorus (P), is major importance for every organism at a larger scale ecosystem functioning productivity. Changes in nutrient availability potential stoichiometric imbalance due to anthropogenic deposition might lead deficiency or alter various ways. In this study, we present 6 years (2014–2020) flux-, plant-, remote sensing data from large-scale manipulation experiment conducted Mediterranean savanna-type with an emphasis on the effects N P treatments ecosystem-scale water-use efficiency (WUE) related mechanisms. Two plots were fertilized (NT, 16.9 Ha) + (NPT, 21.5 Ha), third unfertilized plot served as control (CT). Fertilization had strong impact leaf stoichiometry only within herbaceous layer increased both NPT. Following fertilization, WUE NT NPT during peak growing season. While gross primary productivity similarly NPT, transpiration surface conductance more than The results show that higher but balanced N:P highest WUE. On average, resulted 40% area index (LAI) spring. Increased LAI reduced aerodynamic thus evaporation Despite evaporation, annual evapotranspiration by 10% (48.6 ± 28.3 kg H2O m?2), plot, while remained similar CT (?1%, ?6.7 12.2 kgH2O m?2). Potential causes could be root biomass water uptake rhizosphere priming increase P-mobilization through microbes. net exchange shifted carbon source (75.0 20.6 gC m?2) carbon-neutral [?7.0 18.5 m?2 (NT) 0.4 22.6 (NPT)]. Our show, imbalance, resulting addition (without P), increases less P, NT, which indicates content