Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Bootstrapped values for environmental variables (30 km buffers) selected to explain the spatial density of extirpated species in the present-day landscape (cf. table 2): (a) SO2 and (b) per cent cover of ancient woodland. Values derived for each of the three study sites (cf. figure 2) are indicated on the graphs. Dashed lines show the 95% bootstrap confidence intervals.
