Archivserver der Deutschen Nationalbibliothek

Wirkung von Habitatsstrukturen auf die Benthoszönose 55
increased in fields of modified type I groynes. We conclude there is a response to groyne
adjustment.
For macrozoobenthos, 21 taxa with a mean abundance of 93 individuals m -2 were
considered. The TWINSPAN-analysis (Fig. 4.8, Tab. 4.19) shows that permanent aquatic
habitats with sandy-silty substrates (groups I-II) were characterised by Gomphus flavipes
(Gomphidae, Odonata) and Pisidium henslowanum (Sphaeriidae, Bivalvia). Due to the
semi-aquatic character the shallow water regions at the embankments (groups IV-V) were
dominated by the agile species Chelicorophium curvispinum (Corophiidae, Amphipoda),
Gammarus tigrinus (Gammaridae, Amphipoda) and Dikerogammarus villosus (Pontogammaridae,
Amphipoda).
sample groups groyne field
2000, 2001, 2002
Pisidium henslowanum
2001/2002
P. henslowanum D. villosus
Gomphus flavipes
site 2 site 1
deep water
inclined
Dikerogammarus villosus
shallow water
modified,
site I,
sample
group b,
gravel
2000
I II III IV V transect-group
6 modified type I
12 modified type II
16 inclined groynes
13 modified type I
17 modified type II
13 inclined groynes
9 modified type I
7 modified type II
19 inclined groynes
7 modified type I
6 modified type II
4 inclined groynes
6 modified type I
11 modified type II
15 inclined groynes
number of
sample groups
groyne type
Fig. 4.8:
TWINSPAN dendrogram of macrozoobenthos distribution among sites, years and
habitats within (modified) groyne fields. The up to 60 sample groups per year are
grouped by relative frequency of taxa recorded in 2000, 2001 and 2002 (Tab. 4.19).
Sample groups: white: 2000, grey: 2001 and 2002.