Del|Plant and animal
life in Danish streams and brooks becomes
richer when the vegetation along the banks
is rich and varied too. This is documented
by analyses presented in the report ”Aquatic
Environment and Nature 2009” from the National
Environmental Institute (NERI), Aarhus University.
ALONG RIVER VINDINGE
NEAR HUDEVAD ON THE ISLAND OF FUNEN A WELL-DEVELOPED
RICH FEN EXHIBITING GREAT SPECIES DVIERSTY
OF DIFFERENT MOIST SOIL MACROPYTES IS FOUND.
SPECIES RICHNESS IN THIS TYPE OF BOG DEPENDS
ON RELATIVELY INTENSIVE GRAZING. PHOTO:
BJARNE ANDRESEN, ENVIRONMENTAL CENTRE ODENSE.
Plant and animal life
in Danish streams and brooks becomes richer
when the vegetation along the banks is rich
and varied too. This is documented by analyses
presented in the report ”Aquatic Environment
and Nature 2009” from the National Environmental
Institute (NERI), Aarhus University. The
report is published in collaboration with
the Geological Survey of Denmark and Greenland
(GEUS) and the Nature Agency (the former
Agency for Spatial and Environmental Planning).
Researchers claim that
their analyses show that the so-called close
to-nature stream vegetation gives the animal
and plant life of the streams a biological
lift. More of the species found on land
are found in the streams too. Also more
species of oxygen-demanding small animals
occur, such as mayflies, stoneflies and
caddis flies, and to a certain extent also
higher abundances of trout fry are found.
The biological lift
is partly due to a direct positive effect
of the close to-nature vegetation, allowing
the plants improved opportunities to spread
from their places of growth in the near-stream
zone to the streams themselves. The plants
on land probably provide adult stream insects
with better feeding opportunities and better
possibilities of taking refuge and of swarming
before mating.
Analyses of data for
Danish Fysisk Indeks (‘Danish Physical Index’)
– a tool to estimate the physical conditions
of streams – have moreover shown that the
index generally reflects well the ecological
state and biological diversity of streams.
The index also shows the extent of the agricultural
impact.
”Aquatic Environment
and Nature 2009” also presents other results
from 2009 of the National Programme for
Monitoring of Aquatic Environment and Nature
(NOVANA). In collaboration with the Agency
for Spatial and Environmental Planning (now
The Nature Agency) and GEUS, NERI has prepared
the report based on data gathered by the
environmental centres and by NERI itself.
Eight reports prepared by the National Topic
Centres document the state of streams, lakes,
marine areas, groundwater, point sources,
air and species.
