MAET and also contribute to 50% of the eutrophication.
Pond effluent contributes the other 50% to eutrophication
and also causes FWET and other water quality problems in
canals and rivers. All of these impacts can be addressed by
improving feed use efficiency through better feed formulation
and pond management (Bosma and Verdegem 2011). In
particular, the inclusion of rice bran, a low-quality feed,
decreases efficiency and increases the impact on categories
such as EU and FWET. Replacing locally produced rice
bran by feed ingredients from elsewhere may affect most
impact categories (Pelletier and Tyedmers 2007). This
should be assessed by means of a sensitivity analysis and
region-specific inventory. Pond effluent should also be
studied further in relation to mitigation strategies (e.g., its
use for irrigation, or the possibility for recovering N and P
as struvite).