Feeding the reactors: potentials in re-cycled organic fertilisers

Summary

There is a large and growing interest in producing proteins, oils and other important commodities
in bioreactors. Mineral fertilisers, especially nitrogen
(N) and phosphorus (P), are used to supply the living
organisms with nutrients, and for growing of fungi,
carbon must be applied from sugar or starch products.
This input-for-output approach does not contribute to
cycling of nutrients and organic matter in the society.
Organic*1 agriculture has a strong interest in recycled
fertilisers and best utilisation of organic materials, and appliccable products should be developed not only for
use in agricultural fields but also for other purposes,
such as hydroponics, aquaponics and bioreactors.
Animal bones and precipitated struvite from waste water
are examples of materials which may be applicable in
bioreactors. Containing easily available N and P, recent
studies have shown that these materials are valuable for
amendment of soil fertility and crop productivity in
land-based agriculture. Studies should be initiated to
design bioreactors utilising locally available sources of
nutrients and organic matter, to make the bioreactors
more sustainable and develop organic farming systems
in a context of landless farming.