Without fertilizer application intensively managed tree plantations generally have a negative nutrient balance: within one rotation more nutrients are lost from the system than gained. Constant nutrient exports result in a distinctive depletion of soil nutrient storage. To maintain a balanced nutrient budget and, thus, sustain site productivity it is necessary to compensate nutrient losses. We calculated the quantities of mineral fertilizer required to compensate management-dependent nutrient losses for a plantation site in East-Kalimantan, Indonesia. Calculations are based on estimated nutrient losses for three management scenarios: high-, medium- and low-impact management. Fertilizer compensation for nutrient losses incurred due to tree harvest will increase standard plantation establishment cost by 18-33% and total investment costs by 9-15%. Considering additional nutrient losses due to leaching and erosion as assumed for a low-impact management scenario, standard plantation establishment costs were increased by 20-35% and total investment costs increased by 9-16%, respectively. Fertilizer compensation for a high-impact management scenario, including large nutrient losses resulting from burning of residual phytomass, leaching and erosion, increased standard plantation establishment costs by 29-62%, while total investment costs increased by 13-29%. As a consequence, the internal rate of return (IRR) of the plantation investment dropped from 14% to 9-12%. We calculated major differences in the fertilizer expenses between species. Fertilization costs for Eucalyptus deglupta were generally higher than for Acacia mangium. Considering the high costs for fertilization, we conclude that strategies are to be developed to reduce management-dependent nutrient losses. A low-impact management including alternatives to slash burning and soil-conserving harvesting techniques as well as appropriate site selection are recommended. It is advised to consider nutrient costs in investment calculations of industrial plantations. (C) 2000 Elsevier Science B.V.
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