MIREN dataset
Vegetation composition along mountain roads has been recorded by the
MIREN network since 2007 across 18 mountain regions on 5 continents
(Haider et al. 2022). For the current study we focused on eleven
mountain regions, as the remaining seven did not offer plant cover data
both along the roadside and in the neighboring natural vegetation at the
time of analyses. These regions cover environmental gradients with
elevations ranging from 0 to 4000 m above sea level (m a.s.l) and mean
annual soil temperatures ranging from -5.8 to 27.9 °C. The studied
mountain regions were: the Argentine Andes in Argentina; the Caucasus
Mountains in Armenia; the Australian Alps in Australia; the Chilean
Andes in Chile; the Changbai Mountains in China; the Himalayas in India;
the Northern Scandes in Norway; Mount Teide in the Canary Islands
(Spain); the European Alps in Switzerland; the Rocky Mountains in
Montana (USA); the Blue Mountains in Oregon (USA). In each of these 11
regions, three roads which covered large elevational gradients, were
accessible by the local research teams, were asphalted or covered by
gravel, and were actively used by motorized traffic were selected. The
surveyed road edges were typically highly disturbed, with shallow soils
and often altered surface material due to the road construction, and
reduced vegetation cover (Müllerová et al. 2011), see Figure S1 for
examples. All surveys were first executed between 2007 and 2018,
depending on the region. Surveys are repeated every 5 years, resulting
in currently one (two regions), two (five regions) or three (four
regions) repeated surveys depending on the region.