Soil Fertility and Farming Systems in a Slash and Burn Cultivation Area of Northern Laos

If fallow (the period farmers let the cultuvated soil rest) need to be shorten for some reasons, such as by pressure from increased population, authors think agroforestry system that combines crop cultivation may be a way to keep the soil fertile. Downladable at
http://www.cseas.kyoto-u.ac.jp/seas/41/4/410407.pdf