Abstract
The increasing intensification of aquaculture systems requires the development of strategies to reduce their environmental impacts such as pollution caused by the discharge of nutrient rich sediments into local water bodies. Recycling of fish pond sediments (FPS) as fertilizer has been proposed as a possible solution that may also reduce the reliance on synthetic fertilizers. With a case study in the Mekong Delta, Vietnam, we determined suitable mixtures of striped catfish (Pangasianodon hypophthalmus) pond sediment (PPS) and locally sourced organic amendments of rice straw (RS), or common water hyacinth (WH) to fertilize cucumber plants (Cucumis sativus L.) in an integrated cucumber–giant gourami fish (Osphronemus goramy) farming system. Highest nutrient concentrations were found when mixing 30% PPS with 70% RS or WH. When used in combination with chemical fertilizer, it was found that a 25% to 75% reduction in chemical fertilizer application could be achieved, while also increasing cucumber yields, with the highest yields found when RS was used in organic amendments. In combination with the additional income from fish production, integrated farming systems such as that demonstrated in this study, may increase both farm income and production diversity.
Highlights
Inland aquaculture is one of the fastest growing animal production sectors in the world, and provides a promising way to improve livelihoods and provide export revenues in Asian countries [1].Production is predicted to continue increasing, by optimizing resource use and intensifying existing aquaculture practices [2,3]
We have demonstrated that the use of organic fertilizers can either replace or supplement chemical inputs and have an overall positive effect on yields
Further work is needed to demonstrate the economic benefits to farmers, given the trade-offs between fish production and reduced area available for vegetable production, and between savings on chemical fertilizers and increased labor costs for the preparation of the organic amendments
Summary
Inland aquaculture is one of the fastest growing animal production sectors in the world, and provides a promising way to improve livelihoods and provide export revenues in Asian countries [1].Production is predicted to continue increasing, by optimizing resource use and intensifying existing aquaculture practices [2,3]. In Vietnam, more than half of inland aquaculture fish are striped ( referred to as Pangasius) catfish (Pangasianodon hypophthalmus), which are produced in freshwater earthen ponds and are exported to over 130 countries [3,4]. The total area of ponds used for striped catfish aquaculture has increased approximately 8-fold over the last 20-year period, while total production has increased 64-fold, indicating a rapid and dramatic intensification. This is evident in the Mekong Delta, where striped catfish account for almost 70% of total fish production [5,6,7].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
