Journal of Tropical Forest Science 13(4): 800–815 (2001)800 THE EVOLUTION OF SWIDDEN FALLOW SECONDARY FORESTS IN ASIA

swidden fallow secondary forests in Asia. Swidden agriculture in tropical Asia is a diverse practice, making it difficult to draw general conclusions on trends of the development of swidden fallow secondary forests (SFSF). There is, however, sufficient evidence to recognise trends of a gradual intensification often through the incorporation of extensive tree crop production in SFSF, or a direct conversion to intensive tree cash cropping. Factors contributing to the changes include emerging markets for cash crops or timber and pulp-wood production, government policies and development projects, fire, and population pressures. In Indonesia and mainland Southeast Asia, there is evidence of change towards tree- and cash crop-based production systems. In north-eastern India, there is improved fallow management to sustain or enhance productivity of the shortened swidden agricultural cycle to support a subsistence economy. In Sri Lanka, biophysical factors inhibit the development of intensive agroforestry systems. Although swidden fallow land use has often been stigmatised as leading to forest decline and a related decline in the environmental functions that forests provide, there is sufficient evidence suggesting that conversion of a SFSF-dominated landscape to more intensive tree cropping can have a negative environmental impact. Some general options for the evolution of swidden agriculture under different stages of a land use intensification model are considered