elongated growth and less allocation to roots than plants grown at
high light availability (Barko and Smart, 1981). On the other hand it
is not, to our knowledge, clear whether temperature has any effect
on biomass allocation in aquatic plants.
Phenotypic plasticity is also important in the success of invasive
species, because the more plastic a plant is the higher possibility
that it can establish in new habitats (Richards et al., 2006).
Phenotypic plasticity is the adaptability to environmental change
(Via et al., 1995), and phenoplastic plants are able to acclimate in
morphological or physiological traits to changes in environmental
conditions, e.g. temperature and light (Schlichting, 1986). Hence as
temperature and light change with habitats these parameters can
be important to the establishment of invasive plants in new habitats.
Therefore we can expect that more phenoplastic plants with
a broader tolerance range are more competitive in establishing in
new habitats.
In this paper we present a study on the effect of temperature
and light availability on the initial establishment in terms
of growth rate, photosynthesis and morphology of three invasive
aquatic plants in order to assess their interspecific competition.
The overall objective of our study was to determine the effects
of summer temperature and light availability on the establishment
success of plant fragments in three invasive aquatic plants
and to assess their phenotypic plasticity. Based on these results
we will compare the competitive ability of the three species following
establishment from shoots fragments. The experiment was
carried out in outdoor growth tanks, with temperatures that represent
summer mean water temperature in different climate zones,
and light availabilities to represent shallow and deeper part of
lakes.