2.1 Experimental Design
Our experiment investigated community responses to soil and climate
variation using standardized communities composed of three species:Dactylis glomerata L., Plantago lanceolata L.¸ andLotus corniculatus L. Species were selected based on wide
climatic tolerances and a global distribution, being naturalized on six
continents (Seipel et al. 2012). These species are considered
non-invasive, making them attractive for coordinated studies (Alexander
and Edwards 2010). The experimental communities represent a variety of
herbaceous lifeforms (graminoids, non-leguminous forbs, and legumes),
with limited functional overlap (Dı́az and Cabido 2001). These species
are well suited to experimental studies due to relatively short life
cycles and being readily manipulated. Consequently, these species can be
used as a common currency for plant community dynamics across
coordinated studies.
Seeds used in this study were sourced from Rieger-Hofmann in central
Germany to reduce variability in genetic origin. We partitioned the
effects of local soil from climatic effects by including a reference
substrate treatment (vermiculite mixed with 4g Osmocote fertilizer) at
each site. Vermiculite is a suitable substrate comparable to potting
soil (Wilfahrt et al. 2021). Plants used in the experiment were reared
in a greenhouse in Bayreuth, Germany for four weeks before being
transported to field sites in summer 2017 (Fig. 1 ). The selected
locations were Bayreuth, Germany (350 m a.s.l.); Fendt, Germany (550 m
a.s.l.); Graswang, Germany (850 m a.s.l.); Esterberg, Germany (1300 m
a.s.l.); Stubai, Austria (1850 m a.s.l.); and Furka, Switzerland (2440 m
a.s.l.). These locations represent a wide geographical, climatic, and
soil compositional range (Table 1 ).