ISSN:
1573-5117
Keywords:
zooplankton
;
grass carp
;
aquatic vegetation
;
shallow-water zooplankton sampler
;
experimental ponds
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The effect of the Asian grass carp (Ctenopharyngodon idella Val.) upon the zooplankton in three adjacent experimental ponds (0.139 ha each) was studied for one year. The ponds contained nine species of aquatic macrophytes. Grass carp were stocked into Pond 1 (65 per ha) and Pond 2 (611 per ha) three months after the study was started. At the time of stocking, physichochemical and biological parameters were similar among the ponds. Grass carp did not affect water quality and had little direct or indirect effect upon the zooplankton in the ponds. The abundance and species diversity of zooplankton (number of species, Shannon Index, and Simpson Index) were not significantly different (P 〈 0.05) between ponds prior to grass carp stocking. After stocking with grass carp, the number of species and species diversity were found to be significantly different (P 〈 0.05) between Pond 1 (low grass carp stocking rate) and Pond 2 (high grass carp stocking rate). Additionally, significant differences (P 〈 0.05) in populations between ponds were found for Lecane luna, Monostyla bulla, Lepadella ehrenbergii, Polyarthra sp., and Synchaeta sp. Temporal variation rather than grass carp was probably responsible for those differences. The number of zooplankton per group (Rotifera, Cladocera, and Copepoda) and species diversity were not significantly different (P〈0.05) between ponds containing different stocking rates of grass carp. During the study, zooplankton were collected with a shallow-water sampler. No significant differences (P 〈 0.05) between collections were found for the sampler and a No. 20 mesh nylon zooplankton net.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00019700
Permalink
