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Various researchreports reveal that annually the global forest loss covers alarger area than 10 million hectares.This land use change is causing severe greenhouse gas emissions,soil degradation and erosion and many sorts of harm for various traditional livelihoods of forested regions.Large areas of todays marginal lands such as barren hills and set-a-side fields and pastures have been covered by forest relatively recently in many countries.Even though many areas have been successfully reforested,a common interest to plant forests has been low because of the lack of satisfactory incentives.Value chains of renewable forest based bioenergy will offer attractive opportunitiesfor low carbon economy conceptsand replace fossil fuels with alternate energies.Short Rotation Forestry (SRF) and various production systemsbased on oilseed trees provide challenges to use many-sided ecosystem services and strengthen livelihoods and economic sustainability of rural people.If emphasis will be placed to afforestation and reforestation of marginal lands the contradictions relate to food vs wood may be minimized and future biomass production will meet the requirements of the ethical codes of conduct about sustainable land use.The efficiency of the green plants to convert solar radiation,carbon dioxide and water to biomass and oxygen is low.Sophisticated technologies such as solar panels and wind turbines are usually more attractive for common interest.A short-term and marketing oriented confrontation of various renewable energies is useless.Forest based bioenergy shall have an important role in utilization of rural,marginal lands.Many experimental SRF plantations and even commercial energy farms have revealed that high annual yields such as 10 tons (odt) per ha have been harvested.This has been possible with relatively low contributions of R&D.For improving profitability efforts shall be concentrated especially on planting methods,harvesting technologies and on the optimization of the whole forest bioenergy value chain.This task and outcomes of it are to a great extent dependent on local resources,cultures and the stage of the societal development.These will definethe directions of social and technological innovations and the frames of the cost and benefit concepts.