Nutrient-limited conditions determine the responses of foliar nitrogen and phosphorus stoichiometry to nitrogen addition: A global meta-analysis

Responses of Foliar Nutrient Status and Stoichiometry to Nitrogen Addition in Different Ecosystems: A Meta‐analysis

“…It is not surprising that foliar N concentrations showed only a minor increase in tropical forests, because plant growth in tropical forests is generally not limited by N (Matson et al, ; Vitousek et al, ). The negative response of foliar P concentrations to N addition in temperate and boreal forests, but not in tropical forests, was consistent with previous studies (Campo & Dirzo, ; Deng et al, ; You et al, ), and one main cause for this is the difference in the degree of N versus P limitation among these ecosystems. Generally, temperate and boreal forests are more N limited compared to tropical forests, and the decrease in foliar P may be a result of P consumption due to N‐induced growth (Agren, ; Sardans et al, ; Vitousek et al, ).…”

“…We found that N‐induced effects on foliar N concentrations in grasslands were remarkably greater than those in forests, and a similar pattern was observed for herbaceous and woody plants (Figure ). Similar results have been reported in a previous global‐scale synthesis (You et al, ). The different N‐use efficiencies of the plant growth forms might explain this phenomenon, because woody plants have relatively higher N‐use efficiencies than those of herbaceous plants under N addition (Tian et al, ).…”

“…and N:P are the basis for understanding the effects of N addition on nutrients and have been studied extensively in both manipulative experiments (Huang et al, 2012;Lü et al, 2013) and reviews (Sardans et al, 2017;You et al, 2018;Yue et al, 2017). The results of the present study, showing a significant increase in N (20.18%) and a decrease in P concentrations (2.40%), are consistent with those of previous…”

“…Journal of Geophysical Research: Biogeosciences meta-analyses (You et al, 2018;Yuan & Chen, 2015). Apart from N and P, the significant decrease in foliar K, Ca, and Mg and increase in Al observed in this study corroborate the findings of previous local studies (Flückiger & Braun, 1998;Mo et al, 2008) and review literature at a larger scale (Lucas et al, 2011).…”

“…Nitrogen addition significantly decreased foliar P, K, Ca, and Mg but significantly increased foliar N and Al across all biomes (Figure a), indicating that N addition influences plant nutrient status. Changes in N, P, and N:P are the basis for understanding the effects of N addition on nutrients and have been studied extensively in both manipulative experiments (Huang et al, ; Lü et al, ) and reviews (Sardans et al, ; You et al, ; Yue et al, ). The results of the present study, showing a significant increase in N (20.18%) and a decrease in P concentrations (2.40%), are consistent with those of previous meta‐analyses (You et al, ; Yuan & Chen, ).…”