Figure 3: Correlation between plant δ15N and AI.
From: Aridity threshold in controlling ecosystem nitrogen cycling in arid and semi-arid grasslands
Relationship between AI and foliar δ15N (red points) and root δ15N (blue points) of six examined genera Stipa (a), Leymus (b), Cleistogenes (c), Caragana (d), Reaumuria (e) and Salsola (f). AI=0.32 was used to separate the data (dashed line) and linear regressions were performed between AI and foliar δ15N at both sides when data points were more than 3. Significant correlations were shown with solid lines. The relationship between root δ15N and AI was similar to that between foliar δ15N and AI, hence was not presented.
