Comments on: Integrated Farming Systems in the Andean Foothills in Colombia... by P. Sarria and M.E. Gomez
From: Patricia Sarria <firstname.lastname@example.org>
Answers on questions raised on their paper "Integrated Farming Systems in the Andean Foothills in Colombia"
1. Why did they change from crushing the cane to chopped feeding?
The reasons were:
Change of emphasis of the enterprise to concentrate on reproduction and sale of weaners rather than fattening: it is more profitable. Fully grown pigs are able to extract juice from cane stalk and to consume the same quantity of juice.
Crushing the cane requires an electrical machine and this kind of energy is expensive for the farmer.
Now, farmer's sons do not live in the farm, so he needs to save work.
2. Can the swine excreta mixed with spilled bagasse still be used for biodigesters?
No, now the biodigester in Cipres farm receives cattle manure and household waste water. Other farmers use pig excreta but they use a "trick" to collect bagasse, before it goes into the biodigester. Bagasse causes a problem in the biodigester, it makes a hard layer at the top and gas production is decreasing.
3. How much food and energy (biogas) is produced in this system?
The data are still being processed for the integral system.
4. What other test apart from soil fertility can be used to determine sustainability?
Quality and quantity of water from water source.
Quantity of soil in the water source, specially in the rainy season.
Balance of inputs and outputs in the system.
Patricia Sarria and Maria Elena Gomez