A sweet waterway to food and fuel security
Southeast Asia, which is a world centre of palm biodiversity, can sustainably intensify agriculture through maximizing the full potential of sugar palms as sources of livestock feed and biofuel, according to Craig Jamieson during the First International Agroforestry Congress in Bohol, Philippines, as reported by Amy Christine Cruz
People have been talking about food production and security for quite some time and researchers are looking at how to increase efficiency in food production. One way would be to utilize tree-based systems and their benefits. Another way would be to look at photosynthesis and reducing the inherent losses in a plant’s energy conversion.
Sugar palms have great potential to sustainably produce livestock feed and biofuel but are not yet fully optimized. They are tapped for their sap, which is constituted of 10–20% sugar and are very efficient converters of solar energy to sugar.
There are the usual uses for sugar palms, like nipa vinegar from Nypa fruticans and coconut sugar from Cocos nucifera. Aside from that, the sap from sugar palms can be used to produce biofuel. The amount of potential ethanol produced from nipa (at 12000 litres per hectare) is twice that produced from sugar cane, which only has 6000 litres per hectare. Five to seven times more fuel could be produced from the sap than from the oil of coconut palms.
However, indigenous people have, in fact, been tapping sugar palms since ancient times for feeding their livestock. Captain James Cook, who arrived in Savu, Indonesia in 1770, observed how hogs were fattened up with sugar palm syrup and rice husks, as documented in his book Voyages. The syrup was also used to fatten dogs and fowls.
Apparently, extraction of this sap has been a key to increasing the carrying capacity of the land, as there is a close correlation between sap extraction and dense populations: a benefit much needed in Southeast Asia with its high population density. Even today, some indigenous people still extract the sap from sugar palms.Researchers and practitioners could thus draw from indigenous knowledge and practices in integrating sugar palms into food and energy systems.
The sap is found to be a climate-smart source of livestock feed. Pigs and ducks could take a diet based on sap, which could be their main energy source instead of maize.White corn, which is the main ingredient of animal feeds today, consumes 30% of the arable land in the Philippines for this purpose, mainly as feed for pigs and chickens. Therefore, sugar palms could free more arable land to grow food crops for human consumption, whilst benefiting smallholders and requiring few inputs.
According to Dr Jamieson, further research should be done on technologies that would reduce the cost of tapping sap; methods of stabilizing the extracted sap to avoid fermentation; demonstrations of nipa cultivation, especially in an agroforestry system; and identification of a suitable protein source for co-feeding livestock.
This work is linked to the CGIAR Research Program on Forests, Trees and Agroforestry