whole the world, invasive alien species are recognized among
researchers, as a large problem for biodiversity, economy
and health. This is also the case for Slovenia.
Invasive species spread easily
and are more competitive for resources then other species.
For example we have the plant species canadian Goldenrod
(Solidago canadensis) which grows faster than other
plants and gets more sun but also attract more pollinators
then other plant species. Therefore they are a threat for
more vulnerable species.
The grey squirrel is another
example, this species was first discovered in Great Britain
and nowadays strips the bark from the tree stem, so the
tree dies. This gives a lot of economical damage among forestry.
last example is the case of Ambrosius spp. in the Balkan.
This species makes a lot of pollen, which is very aggressive
outcompetes other native plants (Photo: Nejc Jogan)
are some examples of invasive species and their effects.
But how come they get such an advantages above other (related)
species. One of the explanations is that they don't have
any natural enemies anymore and they can use their energy
for other purposes then defense, like increasing growth
speed, more floral rewards, etc.
now, 42 invasive plant species are recorded for Slovenia.
They mainly are confined to human settlements and places where
they are easily transported like rivers and roads. The large
densities of invasive plant species in the southwest (Koper),
west (Nova Gorica), central Slovenia (Ljubljana and vicinity),
southeast (Novo Mesto) and north east (Maribor), which are
the largest cities and towns of Slovenia. The large stripe
in the north west is the Mura river. The places with the lowest
density of invasive species are the mountaneous parts, like
the Alps and the Sneznik.