Zero waste agriculture

Zero waste agriculture is a type of sustainable agriculture which optimizes use of the five natural kingdoms, i.e. plants, animals, bacteria, fungi and algae, to produce biodiverse-food, energy and nutrients in a synergistic integrated cycle of profit making processes where the waste of each process becomes the feedstock for another process.

Digester

The biogas digester is the heart of most zero waste agriculture (ZWA) systems. It is a 3000-year-old anaerobic digestion process.

History

The integration of shallow microaglal oxidisation ponds was demonstrated by Golueke & Oswald in the 1960s. The widespread global implementation of these systems can be largely credited to Prof George Chan from ZERI. Zero waste agriculture is now practiced in China (ecological farming), Columbia (integrated food & waste management systems) & Fiji (integrated farming systems), India (integrated biogas farming), South Africa (BEAT Coop & African Agroecological Biotechnology Initiative) and Mauritius. The Brazilian government has adopted integrated farming system as a major social technology for the uplifting of marginalized and subsistence farmers through coordination with TECPAR.

Zero waste agriculture combines mature ecological farming practices that delivers an integrated balance of job creation, poverty relief, food security, energy security, water conservation, climate change relief, land security & stewardship.

Practice

Zero waste agriculture is optimally practiced on small 1-5 ha sized family owned and managed farms and it complements traditional farming & animal husbandry as practiced in most third world communities. Zero Waste Agriculture also preserves local indigenous systems and existing agrarian cultural values and practices.

Zero waste agriculture presents a balance of economically, socially and ecologically benefits as it:

1. optimizes food production in an ecological sound manner
2. reduces water consumption through and recycling and reduced evaporation
3. provides energy security through the harvesting of biomethane (biogas) and the extraction of biodiesel from micro-algae all of which from as a by-products of food production
4. provides climate change relief through the substantial reduction in greenhouse gas emissions from both traditional agriculture practices and fossil fuel usage
5. reduces the use of pesticides through biodiverse farming

Oil and biodiesel from algae

In sunny climates, a one hectare zero waste farm can produce over 1000 litres of oil in a year from the chlorella microalgae grown on biogas digester effluent in a 500m² shallow pond. The nutritive high protein waste from the oil extraction process can be used as an animal feed.

See also

• Integrated Multi-Trophic Aquaculture
• Miniwaste