Marine aquaculture of high value species such as fish is generally reliant on external food supplies and has a negative impact on water quality, generating high organic and nutrient loadings. Integrated multi-trophic aquaculture offers a solution to reduce environmental impact of farming systems, culturing complimentary species that can recycle nutrients and reduce nutrient pollution while generating additional products for sale. This article looks at species selection and integration of trophic levels in system design.

Makhana, Euryale ferox is a perennial aquatic herb with gigantic floating leaves that grows in still, shallow water. The sowing and harvesting of makhana seeds, a casual food for rural folk, is conducted by groups of migratory people belonging to the Mallah or Sahini community of Bihar. The makhana seeds are usually fallen and scattered over the bottom of the wetlands (beels) and must be collected manually by diving during September-November. The raw seeds sell for Rs. 60-70 per kg in Assam.

In this issue:

Rearing of spotted scat and pearlspot in coastal West Bengal, India; harvesting Eurayle ferox (makhana) from wetland fisheries of Assam; prospects of ornamental fish culture in seasonal water bodies in Assam; production of tubifex, a new dimention in aquaculture in feeding juvenile fish; invasive apple snails in Brunei Darussalam; aquaculture trends and opportunities in Sindh, Pakistan; NACA Newsletter.

Integrated multi-trophic aquaculture is a flexible concept, on which many variations can be developed and should not be viewed as confined to open-water, marine systems. Freshwater integrated multi-trophic aquaculture, perhaps better known as aquaponics, applies the same principles as those used in marine integrated multi-trophic systems. In particular, using plants to reduce phosphorus (and other nutrient) levels in effluents can help farmers meet water quality guidelines and prevent eutrophication in the environment.

This publication is the major output of a regional programme jointly implemented by FAO and NACA in 2015 to document and disseminate successful practices that contribute to the sustainable intensification of aquaculture in the Asia-Pacific region. Twelve practices are described that contribute to at least one of the following: Improved production and resource use efficiency (land, water, feed, energy); improved environmental benefits; strengthened economic viability and farmers' resilience; and improved social acceptance and equity.