The IFS can remove all these constraints by not only solving most of the existing economic and even ecological problems, but also provide the needed means of production such as fuel, fertilizer and feed, besides increasing productivity many-fold. It can turn all those existing disastrous farming systems, especially in the poorest countries, into economically viable and ecologically balanced systems that will not only alleviate poverty, but can even eradicate this source completely.


INTEGRATION

The ancient combination of Livestock and Crop activities had helped farmers in the past, almost all over the world, to use the manure as fertilizer for crops, and the crop residues as feed for livestock. However, most of the manure usually lost up to half its nitrogen content before it became nitrate and was readily available as fertilizer to plants. The quantity also became inadequate as the population increased, so chemical fertilizers and artificial feeds had to be purchased, eroding the small profits of the small farmers.

The more recent integration of Fish with the Livestock and Crop has helped to improve the fertilizer and feed supplies, plus the high market value of fish as feed and/or food increasing the incomes substantially. Technically, this important addition of a second cycle of nutrients from fish wastes has benefited the enhanced integration process, and has improved the livelihoods of many small farmers considerably. This has now been documented by M. Prein of ICLARM Malaysia in "Integration of Aquaculture into Crop-Animal Systems in Asia."

It should be noted that the first of the two cycles of nutrients from the livestock is used to fertilize the growth of various natural plankton in the pond as fish feeds. Yield of fish was increased up to three-to four-fold with polyculture of many kinds of compatible fish feeding at different trophic levels, as practiced in China, Thailand, Vietnam, India and Bangladesh. The fish, after consuming the plankton, produce their own wastes that are converted naturally into the second cycle of nutrients, which is then used to fertilize various crops on both the water surface with floats, as practiced in parts of China, and on the surrounding dykes.

However, even if this has been a big step forward, it still required some external input to increase farm productivity and produce processing in agro-industry. So it has remained inadequate to lift the small farmers out of poverty, because of the continuously rising costs of the inputs, such as chemical fertilizer, artificial feed and fossil fuel, which had adverse effects on yield and quality, produce processing, and farming economics.
Further innovations as well as increased productivity are necessary to push the integrated farming system almost to perfection. This is what the ZERI (Zero Emissions Research & Initiatives) Integrated Biomass System (IBS) has been trying to do, as documented by Gunter Pauli in "Upsizing."


DIGESTION AND OXIDATION

The most significant innovation is the introduction of the DIGESTER AND BASIN in the waste treatment processes of the integrated farming system. One big problem with livestock waste, which contains very unstable organic matter, is that it decomposes fast and consumes oxygen. So for any specific pond, the quantity of livestock wastes that can be added is limited, as any excess will deplete the oxygen and affect the fish population adversely, even resulting in fish kills.

We should also seriously question the erratic proposals, presently being made by local as well as foreign experts in Mauritius, while ignoring past failures worldwide and wasting scarce funding to repeat the same mistakes, such as:

• spreading the livestock wastes on land to let them rot away and hope that the small amount of residual nutrients left after losses of volatile ammonia and nitrite, if they are not washed away by rain or irrigation water, can improve the soil fertility
  
  

• composting the livestock wastes with household garbage to get a low-quality fertilizer, again because of the ammonia and nitrite losses, instead of digesting the livestock wastes into higher-quality fertilizer, and using the garbage to produce high-protein feeds such as earthworms and having their castings and garbage residues as better soil conditioner; and
  
  

• treating the livestock wastes ineffectively as well as inefficiently in outdated septic tanks for not much financial or other benefits, while the badly treated effluent is just as dangerous as the waste itself

Digestion of the livestock waste under closed ANAEROBIC conditions, is followed by oxidation in open shallow basins with natural algae providing the free oxygen through photosynthesis, before letting the treated waste effluent flow into the fish pond. This can convert almost 100% of the organics into inorganics, which will not consume any oxygen to deprive the fish of this important life-sustaining item. So, theoretically, it is possible to increase the quantity of waste ten-fold into the pond without any risk of pollution. Moreover, the big daily increase in readily usable nutrients can be beneficial to the system, provided that they are totally utilized in both fish and crop cultures, or they can create problems of eutrophication in bodies of water, including the fish ponds themselves, which are then counterproductive.


References

1. Chaboussou, F., 1980. Les Plantes Malades des Pesticides
Editions Debard, Paris, FRANCE

2. Chan, G.L., 1996. The Rural-Urban Connection
World Bank: Sustainable Development Conference, Mimeo 18 pp, USA

3. Chan, G.L., 1993. Aquaculture, Ecological Engineering: Lessons from China
AMBIO, Vol. 22.22 No. 7, November 1993, pp 491-494. SWEDEN

4. Chan, G.L., 1985. Integrated Farming System
Elsevier Science Publications, Amsterdam, NETHERLANDS

5. DeZeeuw, H. (ETC.), Rijnsburger, J. (WASTE), 1998. Sustainable Wastewater Recycling Management in Support of Community Development
ETC, Leusden, NETHERLANDS

6. Kiely, G., Environmental Engineering
McGraw-Hill International Editions, USA

7. Mulhall, D., Hansen, K., 1998. A Cycle of Cycles - Guide to Wastewater Recycling in Tropical Regions
Hamburger Umweltinstitut e. V., GERMANY & European Commission, Brussels, BELGIUM

8. NACA, 1989. Integrated Fish Farming in China
NACA Technical Manual 7, Bangkok, THAILAND and Asian-Pacific Regional Research & Training Centre, Wuxi, CHINA

9. Pauli, G., 1998. Integrated Biomass System - UPSIZING pp 152-180
Greenleaf Publishing. Sheffield, UK

10. Prein, M. ICLARM contribution No. 1611, 2001. Integration of Aquaculture into Crop-Animal Systems in Asia. Agricultural Systems 71 pp 127-146.
Elsevier Science Ltd., Amsterdam, NETHERLANDS

11. Zhong, G.F., Wang, Z.Q., Wu, H.S., 1997. Land-Water Interactions of the Dike-Pond System
Presses Universitaires de Namur and Eco-Technologie des Eaux Continentales. BELGIUM