Researchers working on swidden agriculture showcased the changes at an international seminar in the Philippines in March 2015, discussing how the shifts can have socio-economic and environmental impacts.
The research team are part of a systematic review of long-fallow swidden systems in Southeast Asia, led by the University of Melbourne with the World Agroforestry Centre Philippines and a number of other Australian universities. The review is supported by the Evidence Based Forestry program of the Center for International Forestry Research and the CGIAR Research Program on Forests, Trees and Agroforestry.
Swidden, also called shifting agriculture, is the intermittent clearing of forests in order to grow staple food crops. A long fallow period follows after the first few harvests, which restores the productivity of the land, and some of the forest.
Swidden is generally thought of as a destructive practice because of the use of fire for clearing vegetation. But in Southeast Asia, as in many other parts of the world, the practice has undergone significant changes over recent decades, leading some researchers to challenge the prevailing perception.
The number of farmers in Southeast Asia practising swidden is estimated at14-to-34 million, however, some traditionally swidden-farming populations have stopped practising it.
In Sarawak, Malaysia, a number of ‘longhouse’ communities of the Dayak indigenous group are moving away from agricultural and forest activities, said Dr Rob Cramb, of the University of Queensland. From all of the households doing swidden agriculture with hill ‘paddy’, or rice, in 1980, none of the households now practise it. They have no more seeds to plant and no intention to go back to swidden cultivation.
Dr Ole Mertz from the University of Copenhagen discussed the impact of the changes in swidden agriculture. He said that moving from swidden agriculture to other land uses, for example, monoculture plantations, mostly increases farmers’ incomes and give them more access to health and education. However, farmers could also experience negative impact on their food security, access to land and cultural identity.
In the Dayak case, they now give more importance to human capital, such as formal education, skills and experience, for which they migrate out of their communities, and rely more on wages, pensions and remittances: all non-rural sources of incomes.
Land-use change from swidden may also have environmental impact, according to Dr Mertz. Changes in swidden agriculture could either increase or decrease forest cover. For example, if swidden were converted to ‘conservation forest’, forest cover would definitely increase. However, if it were converted to other land uses, such as solely for annual crop cultivation, forest cover will decrease, because long-fallow swidden systems still produce a sort of secondary forest.
One implication is that stopping swidden practice does not necessarily stop deforestation. Moving from swidden to other land uses could also negatively affect biodiversity and soil fertility because land is used more intensively.
The Dayak communities in Sarawak are now looking at what they should do with the fallow land not used for their livelihoods. They currently have a rubber mini-estate of 100 ha developed by the Department of Agriculture and have also proposed large-scale oil-palm development. Another option would be to use the land as a forest reserve that could double as a carbon and biodiversity store. How these changes would affect the forests and carbon emissions remain to be seen.