How to produce zooplankton and phytoplankton in a pond?
Answers
The present study was designed to estimate zooplankton abundance qualitatively and quantitatively in different Fish-Livestock Integrated Farming Systems (FLIFS) over the Non Integrated Fish-Livestock Farming System (NIFLFS) in Terai region of West Bengal. Three treatments in triplicates for four consecutive years (2008–2011) were studied in Belacoba village of Jalpaiguri district involving nine pond of 0.01 hectare (ha) namely, NIFLFS (Control): The aquaculture was not integrated with the animal waste, FLIFS -I: Integration of cattle manure with aquaculture and FLIFS -II: FLIFS-I+ ducks grazing on the ponds. Zooplankton samples were collected bimonthly from the treated ponds for the analysis (qualitatively and quantitatively). Ponds under FLIFS-II and FLIFS-I were found to contain significantly higher concentration of zooplanktons (131±12 no l−1 and 128±11 no l−1, respectively) than NIFLFS (27 ± 2 no l−1). The identified zooplanktons were under 4 orders namely copepoda, rotifera, cladocera, and Diaptomus. Dominant groups of the zooplankton available in all the samples were observed to be Copepoda and Cladocera represented by Cyclops sp.and Daphnia sp., respectively. Total seven and six species were identified in the FLIFS-II and FLIFS-I, respectively in comparison to the four species in NIFLFS. In the present study the Daphnia was also significantly increased by 32.8% and 31.8% in FLIFS-I and FLIFS-II, respectively, where frequently manure was applied. Again Bosmina sp. was observed to be contributing in the FLIFS-II where ducks are grazing and the duck droppings are introduced in the ponds. Hence, it was concluded that utilization of cow dung and duck manure for aquaculture can successfully increase the availability and diversity of the natural food (zooplankton) to support the growing fishes under the integrated fish farming systems followed in the terai region of West Bengal.