Abstract
Even now the evaluation of swidden agriculture remains controversial while most of the causes of deforestation seem to have been made clear. Swidden agriculture is quite reasonable from an ecological point of view, but it is so fragile that it has changed drastically, like as the Kenyah's swidden system in Borneo island. Local resource management systems consist of three sub-systems such as swidden system, communal forest system, and the other systems. The sustainability and fragility of local resource management system are examined based on the commons discussion. To examine the ecological function of the commons, sustainable utilization is categorized into three types to serve as a conceptual device: "haphazard", "incidental", and "intended" sustainable use. It is concluded that the Kenyah's systems, from a view point of ecological function, are regarded as "loose local-commons" absent of "intended" sustainable use. This seems to be the reason why their systems go through a drastic changes in spite of ever being sustainable. On the other hand, the systems except for the other sub-systems can be considered to be "tight local-commons" from a view point of socio-cultural function. As a result, resource management systems are still effective in the local level. The framework to evaluate local resource management systems, shown in the paper, must be convenient to set up participatory forest management at local level. We can judge whether an application of local technology is reasonable or not, by examining the ecological function of the commons. By examining the sociocultural function of the commons, we can consider which is more reasonable to apply "endogenous bottom up approach" or "professional-guided participatory approach".
