A note on the culture of Chanos chanos (Forskal) at Brackishwater Fish Farm, Kaninada

The culture of Chanos chanos to marketable size within a three months period, is described. Procedures involved include phased manuring coupled with proper water management to keep up enhanced primary productivity. Results show that, under monoculture, with low-input technology it is possible to produce 3,000 kg fish per hectare per year.

Break through in 10 million fry production at Khutelabhata fish seed farm, Durg, Madhya Pradesh

This paper presents a resume of the work carried on the production of 10 million major carp fry by stocking at the rate of 10 million spawn per hectare in 38 nursery ponds covering 2.1 ha. water spread area at Khutelabhata fish seed farm, Durg, Madhya Pradesh. Observations made on the effect of various types of feed on survival and growth rate of Indian Major carp fry in nurseries are reported. Physico-chemical parameters and plankton populations in the three sets of nurseries are given. The experiments indicates that optimum survival rate of fry can be obtained by feeding tender spawn with animal protein feed. The economic viability of the experiment discussed shows that for a little increase in the expenditure on improved artificial food the survival and growth of fry can be enhanced.

Community metabolism, P/R ratio and photosynthetic efficiency of a brackishwater farm

The productivity level of a brackishwater fish culture farm consisting of 25 ponds, with a water spread area of 2.5 ha, was studied. Gross community photosynthesis of the farm was found to be 46.32 Kcal/m2/day, which is equivalent to the release of 13.23 of O2/m2/day, or the fixing of 4.10 gC/m2/day. Respiratory demand of the farm was estimated to be 44.66 kcal/m2/day, which is equivalent to the uptake of 12.76 g O2/m2/day or the utilization of 3.95 gC/m2/day. Photosynthetic efficiency of the farm was high at 2.26%. The P/R ratio was 1.04, showing eutrophic nature.

Increasing farm income by introducing fish culture in deepwater rice environment

Fish culture in deep-water-rice (DWR) environment using net pen and polder systems was evaluated. In net pen rohu and Thai silver barb were cultured, whereas a 5-species combination (rohu, mrigal, common carp, grass carp and Thai silver barb) were cultured with BR3 rice variety and DWR. Boro-fish production system produced 2.8 t/ha of fish and 7.33 t/ha of rice in polder system with 5-species combinations.

Centrifuge tests investigating inclined grout micro-piles as a method of liquefaction remediation for existing buildings

This paper presents a series of centrifuge tests carried out to investigate the performance of non-structural inclined micro-piles as a potential liquefaction remediation method for existing buildings. Both a single-degree-of-freedom frame structure and a two-storey, two-degree-of-freedom frame structure were used as model buildings in these tests. Centrifuge tests were carried out with and without micro-piles in the foundation soil for each structure. Results primarily from the tests with the SDOF structure are presented in this paper. It is found that the micro-piles have some beneficial effect by increasing shear strains in the soil in their vicinity and hence causing dilation in these zones. However, they also increase structural accelerations by transmitting accelerations from deep in the soil and the beneficial effects from increased dilation are outweighed by the detrimental migration of pore pressures.