European Red List of Vascular Plants - European Commission

The results of the assessment of CWR show that a
significant proportion of species are threatened with
extinction and that many are also likely to become
threatened in the near future unless immediate remedial
action is taken. Crop complexes that are of particular
concern include beet, brassicas, oat, lettuce and wheat.
Although a significant proportion of the species assessed
are thought to have a stable population trend, a major
concern is that for almost half of the species assessed, the
population trend is unknown, underlining our lack of
knowledge of the status of these species in the wild. More
than half of the species evaluated as threatened or Near
Threatened are in decline and are therefore in urgent need
of conservation attention. This loss of plant diversity can
occur at both taxonomic (species) and genetic level. It is
difficult, if not impossible, to quantify the loss of genetic
diversity within CWR species; however, it must be
faster than the loss of species, because there will be some
genetic erosion from the species that remain extant and
complete loss of genetic diversity from those species that
become extinct (Maxted et al. 1997c, 2003). It therefore
seems likely that virtually all CWR species are currently
suffering loss of genetic diversity to varying degrees.
Maxted et al. (1997c) estimated that 25–35% of plant
genetic diversity would be lost between the ratification
of the CBD in 1993 and the 2010 Biodiversity Target
date. Loss of any genetic diversity means that plants may
not be able to adapt to changing conditions quite so
readily in the future – in a time of ecosystem instability
this is a serious concern, since many of these species form
the basis of our future food security. Further, in terms
of the raison d’etre for singling out CWR as a specific
group of plants, it is their utility to plant breeders and the
maximum range of CWR genetic diversity that breeders
require, so any loss of diversity impacts on their potential
utility and thus their value as a natural resource.
At first sight, the level of threat in the aquatic plants
group appears low, especially compared to other species
groups bound to aquatic habitats. Aquatic animal species
are among the most threatened in Europe with 44% of
freshwater molluscs, 37% of all freshwater fish and 23% of
amphibians being threatened with extinction. The main
reason for the low percentage of threat in aquatic plants
is that they are mostly widespread and the number of
restricted endemics is low compared to the other groups.
Among aquatic plants there are species that are adapted
to survive periods without water – this is not the case
for freshwater molluscs or fishes. Some plants are also
quite mobile by using seed distribution via birds or wind.
However, it is notable that the most widespread threat
for freshwater species is water pollution, in particular
from agriculture, although this is not necessarily the most
serious threat.
6.2 Major threats to European vascular
plants
Vascular plants are subject to the same threats as any
other wild species, which, fundamentally, are caused
by the conflict between supply and demand for natural
resources (Stuart and Adams 1990). The species assessed
are therefore mainly affected by loss, degradation and/
or increased fragmentation of their habitats that result
from unsustainable human mismanagement of the
environment.
Intensified livestock farming and in particular intensive
grazing activities were identified as the major threats to
the policy species and CWR. Many of the species assessed
require a certain level of grazing to keep the habitat open
and to protect the species from the encroachment by
plants that compete more aggressively for resources and
light; therefore, while intensive grazing poses a major
threat, a lack of grazing is also a threat to some European
plant populations. This has important implications for
the conservation of those species as they require careful
habitat management. The second major threat to the
policy species and CWR is posed by recreational activities
and infrastructure development related to tourism and
urbanisation. Whereas the first leads to species disturbance
such as trampling and habitat degradation, the latter causes
actual habitat loss. The spread of invasive alien species is
the third most serious threat for those two groups. Policy
plants are also seriously affected by problematic native
species, often in the form of overgrazing. Collection
of wild plant species is causing a loss of species and a
reduction of their reproductive success, this has been
identified as an important threat for the policy plants in
particular. Some species are used as medicinal plants or
for food, others are collected for their beauty. If species
are known to become rare or threatened with extinction,
it seems to increase their value for collectors and increases
the pressure on those species which in the end proves
detrimental to their survival.
Aquatic plants are also affected by the threats named
above, but ecosystem modifications poses an overall
more severe threat. Drainage and the abandonment of
traditional grazing activities fall under this category. The
transformation of wetland habitats into agricultural fields
and an intensification of agricultural activities have severe
effects on aquatic plants. Intensification is accompanied
by a higher input of nutrients and pesticides which get
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