KONINKLIJKE ACADEMIE VOOR OVERZEESE WETENSCHAPPEN ...

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lebes, Assulina seminulum, Difflugia acuminata, Moina rectirostris,
Ceriodaphnia rigaudi, Moina brachiata, Eucyclops macrurus, Eucyclops paras-
inus, Eucyclops serrulatus, Mesocyclops leuckati, Mesocyclops oithonoides,
Osphranticum labronectum, Limnoneaea genuina, Polyarthra sp, Trichocerca
longiseta, Brachionus falcatus, Polyarthra sp, Filinia terminalis, Sacculina sp.
The lowest density of zooplankton (2.889 ± 2.062 ind./l) was in treatment II
(50 fish/m2) and the highest density of zooplankton (21.667 ± 1.573 ind./l) was
in treatment I (30 fish/m2).
3.2.3. Zoobenthos
Time (months)
—•— Treatment I —■— Treatment II
Fig. 15. — Density of zooplankton (ind./l) in intensive culture system.
Zoobenthos organisms are mainly living in the bottom of the water bodies of
culture systems and their distribution depends on the structure of soils and on the
organic nutrient in the sediments. The results show that the main taxa were
Insect, Polychaeta, Oligochaeta and Prosobranchia. The highest density was
observed for Insect and Polychaeta (fig. 16).
The main taxa of Insect was only Chironomus, other families had only
2-3 species. In treatment I the density of zoobenthos fluctuated from 1.71-
4.28 g/m2 and 2.15-3.59 g/m2 for treatment II. The average of zoobenthos density
in treatment I (3.03 g/m2) was significantly (p < 0.05) higher than treatment II
(2.67 g/m2). In the research results, the number of zoobenthos increased gradually
while organic substance was accumulated at a maximum at the end of this
experiment.