| Bamboo talun-kebun is one of the traditional agroforestry systems in West Java, Indonesia, in which annual food crops are alternated with a fallow period of bamboo and trees. Because of increasing population pressure, some farmers are intensifying the cropping, shortening the fallow stage, or replacing the bamboo with other cash crops. These changes raise concerns about the maintenance of site productivity. This study was undertaken to analyze the sustainability of the bamboo talun-kebun under the current management practice by examining the biochemistry of N, P, K, Ca, and Mg in various stages of the cycle, and by using this information to assess the effects of extending the period of cropping on production. The energy efficiency and some other aspects of the talun-kebun management practice were also examined.Plant biomass and the accumulation and distribution of N, P, K, Ca, and Mg in plants and in mineral soils were determined over a complete bamboo talun-kebun rotation cycle to provide the data needed for the biogeochemical analysis. The dynamics of litterfall, forest floor, and soil organic matter mass and nutrients were studied. The inputs and outputs of nutrients to and from the system in precipitation, soil leaching, fertilizer, biological fixation, and losses in the burning of forest floor and slash were measured and/or estimated.Approximately 96.5 t haThe nutrient budget analysis of the cycle and a tabular analysis to assess the consequences for nitrogen uptake and biomass production of extending the period of cropping and reducing the length of the fallow emphasized the importance of the fallow stage for the maintenance of site productivity.The talun-kebun is an energy and economically efficient system because the major energy input is solar energy, and the cost of production is low. The ratio of net energy output/input of food crop production was 38:1. |
