Do Nitrogen Concentration and Forage Quality of the Moss Racomitrium lanuginosum Increase with Latitude?

Figure 1

(a) Map showing locations of sample sites and published material. (b) Moss % N concentration plotted against latitude. Polynomial regression line; 𝑅²=36.1%, 𝑛=27, 𝑃<.01. (c) Box plots showing median interquartile range and 95% confidence intervals of moss % N grouped against predicted regional N deposition derrived from model predictions [12]. (d) C/N ratio (log axis) of moss plotted against latitude. Regression line; 𝑅²=36.0%, 𝑛=20, 𝑃<.01. In (a), (b) and (d), circles represent 2007 samples, triangles samples from 1990s, and crosses published material (C/N data not available in published material). The dashed line at 66.56° represents the latitude of the Arctic Circle.