Appendix B. A figure showing acetylene reduction activity as a function of soil available nitrogen.
FIG. B1. Caption: (a) Coriaria arborea, (b) foliose lichen, (c) bryophyte, and (d) litter acetylene reduction activity are shown as a function of soil inorganic nitrogen availability across the Franz Josef chronosequence. As in Fig. 2, summer data are red, winter data are blue, and we have added a small random horizontal jitter to each datapoint to improve readability of overlapping data. Also as in Fig. 2, data below the minimum detection limit are displayed as half this limit, but our maximum likelihood estimates - shown in solid lines - do not make this assumption (see main text and Appendix A). Note that the units of (a) differ from (b)–(d). As in Fig. 2, the vertical axes are displayed on a logarithmic scale, but unlike Fig. 2, the horizontal axes are displayed on a linear scale. |