10.5061/DRYAD.8Q02M
Leinaas, Hans Petter
University of Oslo
Bengtsson, Jan
Swedish University of Agricultural Sciences
Janion-Scheepers, Charlene
Stellenbosch University
Chown, Steven L.
Monash University
Stellenbosch University
Data from: Indirect effects of habitat disturbance on invasion: nutritious
litter from a grazing resistant plant favors alien over native Collembola
Dryad
dataset
2015
non-additive effects
Hypogastrura manubrialis
resource patchiness
renosterveld
2015-07-27T15:49:34Z
2015-07-27T15:49:34Z
en
https://doi.org/10.1002/ece3.1483
52799 bytes
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CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Biological invasions are major threats to biodiversity, with impacts that
may be compounded by other forms of environmental change. Observations of
high density of the invasive springtail (Collembola), Hypogastrura
manubrialis in heavily grazed renosterveld vegetation in the Western Cape,
South Africa, raised the question of whether the invasion was favored by
changes in plant litter quality associated with habitat disturbance in
this vegetation type. To examine the likely mechanisms underlying the high
abundance of H. manubrialis, cages with three types of naturally occurring
litter with different nutrient content were placed out in the area and
collected after different periods of time. Hypogastrura manubrialis was
mainly found in the nutrient-rich litter of the yellowbush (Galenia
africana), which responds positively to disturbance in the form of
overgrazing. This suggests that invasion may have been facilitated by a
positive interaction with this grazing resistant plant. By contrast,
indigenous Collembola were least abundant in yellowbush litter. Negative
correlations between high abundance of H. manubrialis and the abundance
and diversity of other species suggest that competitive interactions might
underlie low abundance of these other species at the patch level. Group
behavior enables H. manubrialis to utilize efficiently this ephemeral,
high quality resource, and might improve its competitive ability. The
results suggest that interactions among environmental change drivers may
lead to unforeseen invasion effects. H. manubrialis is not likely to be
very successful in un-grazed renosterveld, but in combination with
grazing, favoring the nutrient-rich yellowbush, it may become highly
invasive. Field manipulations are required to fully verify these
conclusions.
DRYAD_Leinaas_et_al_2015Number of Collembola in litter traps (h=4 cm, Ø =
7.5 cm) at three sampling dates after the traps were placed out in a
renosterveld vegetation in Western Cape, South Africa
South Africa
Western Cape