ISSN 10674136, Russian Journal of Ecology, 2015, Vol. 46, No. 4, pp. 325–331. © Pleiades Publishing, Ltd., 2015.
Soil nitrogen is the most limiting nutrient for weeds
growth in most undisturbed ecosystems (Vitousek and
Howarth, 1991), such as grasslands, heathlands, for
ests and shrublands (Allen et al., 1998; Bytnerowicz
and Fenn, 1996). The enrichment of soil nitrogen
increases plants biomass production, but decreases the
biodiversity of ecosystems, usually causing dramatic
changes in species dominance (Dukes and Mooney,
In the past it has been proposed that limiting
resources prevented the invasion of some plant species
(Rickey and Anderson, 2004). Removal of these limit
ing factors may allow plants to invade the places where
they were previously excluded. Nitrogen is an environ
mental limiting factors in numerous ecosystems (Til
man, 1990). Once these constraints are removed from
the environment, species that formerly being limited
may increase in abundance (Rickey and Anderson,
2004). For instance, Brooks (2003) suggested the
growth of invasive plant species increased after nitro
gen was added to the soil. In addition, the invasive
Trin. benefited from higher
nitrogen, and therefore was more likely to replace the
indigenous competitor species
Loisel. in nitrogenrich environments (Rickey and
Anderson, 2004). Some other invasive plant species,
(Spreng.) King and Robinson
L. also had a more competitive advan
tage in nitrogenrich soil than in nitrogenlimited soil
(Hawkes et al., 2005).
(L.) Kuntze, which is native to
South America, is a notorious weed worldwide.
has intensively colonized in Hebei Prov
ince, China (Zhang et al. 2008). Ecological problems,
including threatens to human health and reduced
biodiversity of the native ecosystem have occurred,
since its invasion into China (Li et al., 2010).
has a very wide range of habitats and its growth
was influenced by environmental conditions such as
the light, soil moisture and salinity (Ren et al., 2008).
was shown to be more sensitive to
nitrogen application and had superior nitrogen utiliza
tion efficiency than native species (Huangfu et al.,
2010). However, rare studies have directly compared
the competitive ability between invasive and native
species at different soil nitrogen levels.
Field investigation shown that the competitive
plant species of
(L.) Beauv (Ren
et al., 2008).
have been selected as competitors in field experiments
because of their differences in growth habit and height
(Lü et al., 2011).
, an annual native
Effects of Nitrogen Addition on the Competition Between the Invasive
and Two Native Species
FengJuan Zhang, FengXin Chen, Qiao Li, HaiYun Xu, and YueYue Jia
College of Life Science, Hebei University, Baoding, Hebei, 071002 China
Received October 27, 2014
(L.) Kuntze, an invasive plant in China, has caused serious environmental and
agricultural problems. A competition experiment with and without nitrogen fertilizer under field conditions
was conducted to determine the competitive ability of the invasive plant species with two native species. The
results showed that fertilization only increase relative growth rate of
in the monoculture and the
photosynthetic rates of the invasive species when it competed with
The growth of
was inhibited, while the growth of
was promoted by competition with
Nitrogen fertilizer addition significantly decreased the positive effect and increased the negative effect on
The higher relative growth rate and net assimilation rate might give
advantage in comparison to
in the competition with
due to its greater ability to uti
lize available resources.
(L.), competitive ability, nitrogen fertilizer,
: RGR: relative growth rate; SLA: specific leaf
area; NAR: net assimilation rate,
: Net photosynthetic rate;
PPFD: photosynthetic photon flux density; CRCI: corrected
index of relative competition intensity; LWR: Leaf weight ratio;
LAR: Leaf area ratio.
The article is published in the original.