Аннотация
This chapter describes relationships between environmental stress
and the reaction of plants
thereupon. Plants might react to environmental stress on various levels:
on the biochemical,
cellular, or morphological scale, and at species or population level.
The characteristics of
organisms change with their size (allometric relationships), with
their life history (and related
allocation strategies) and with their functional evolution. We discuss
in this chapter, what kind
of information may be derived from the composition of the vegetation
(species diversity and
species abundance). We provide insights in the effects of environmental
stress on biodiversity.,
e.g. shifts in communities, the loss of species and appearance of
new species. These
insight may contribute to the validation of environmental standards.
Another aspect we have
dealt with is the use of plants to track climate and land-use changes
in history. The use of
plants as a bioaccumulative indicator is not discussed.
When using a bioindicator, it is particularly important to state clearly
which stress factor
it is supposed to be sensitive for. It is shown in this chapter, that
the sensitivity of plants for,
e.g., heavy metals is dependent on the combination of morphological,
anatomical and phenological
characteristics of the plant. Evergreen plants are far more sensitive
than early spring
green plants, while shrubs are more sensitive than trees and obligate
annuals (therophytes)
are more sensitive than facultative annuals. Dependent on the character
states, plants, or plant
parts, may be, and are, used as climatic indicators, e.g., life forms
and leaf anatomy in relation
to temperature, rainfall and atmospheric CO2, or as reliable ecotoxicological
tools
(rootlet growth in testing solutions; and as time proxies (e.g. tree
rings).
The composition of plant communities can deliver a lot of information
about environmental
conditions. Further the implications of the so-called Ellenberg approach
are analysed.
Changes in vegetation over time indicate changes in climate patterns,
as the main biotic
response to climate change is migration, to track optimal conditions
for growth. The type of
photosynthetic pathways (C3 versus C4 photosynthesis) and leaf anatomy
of plants as indicators
for climatic changes is discussed and coupled with atmospheric tele-connections
like
El Ni�o and its antagonist La Ni�a.
A very interesting way of bioindication by plants is used by palynologists.
Their use of plant
remains as proxies for vegetation history and human influence provides
information about the
development of the present society, also from periods where there
were no written sources.
They show us what the world looked like in historic and pre-historic
era. This latter work can
be seen as assessments of early human impacts on the environment.
- autecology,
- biodiversity,
- change,
- character
- climate
- ecotoxicology,
- effects,
- ellenberg,
- flora,
- heavy
- ieps,
- insecticide,
- metal,
- paf,
- palynology,
- photosynthesis,
- plants,
- state,
- synecology,
- vascular
- vegetation
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